<RECORD 1>
Accession number:20164903093314
Title:Relationship between land cover-landscape spatial characteristics and aerosol optical depth in Ebinur Lake Watershed
Authors:Wang, Xiaoping (1, 2); Zhang, Fei (1, 2, 3); Jing, Yunqing (1, 2); Zhang, Haiwei (1, 2); Li, Zhe (1, 2)
Author affiliation:(1) College of Resources and Environment Science, Xinjiang University, Urumqi; 830046, China; (2) Key Laboratory of Oasis Ecology Ministry of Education, Xinjiang University, Urumqi; 830046, China; (3) Key Laboratory of Xinjiang Wisdom City and Environment Modeling, Urumqi; 830046, China
Corresponding author:Zhang, Fei(zhangfei3s@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:273-283
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The rapid development of economy in the Ebinur Lake Watershed has caused a swift transition of Land use/cover-landscapes pattern, which directly or indirectly affect the atmospheric environment. Atmospheric particulate is one of the major air pollutants in China. The aerosol optical depth (AOD) which represents the integrated column of aerosols is one of the most important indicators of air quality. Ebinur Lake Watershed in Xinjiang Province was chose as a sample study area of the relationships between land cover-landscapes pattern and aerosol optical depth (AOD). Environmental mitigation satellite (HJ-1B CCD) data taken on September 30th, 2011 and September 30th, 2015 were used for AOD analysis to correlate with land use/cover types. Land cover in the study area was classified into seven categories by using the maximum likelihood supervised classification as cropland, forest-grassland (including natural forests and grasslands), desert, lake bed, water, saline land, and other land cover (including the built-up area, mountains, etc.). Nine landscape indices were used, which are largest patch index (LPI), percentage of landscape (PLAND), patch density(PD), landscape shape index (LSI), aggregation index(AI), interspersion and juxtaposition index (IJI), Shannon's diversity index (SHDI), contagion index (CONTAG), and patch cohesion index (COHESION). Combined with the uncertainty in the improved algorithm, and pixel by pixel data, aerosol optical thickness was calculated for September 30th, 2011 and September 30th, 2015. Fractal analysis and contribution analysis were applied to quantitatively illustrate the impact of land use/cover on AOD patterns. Watershed air pollution patterns could be related to the land cover-landscapes pattern changes. Using fractal analysis, the relationship between variations in the AOD and different land cover types could be further understood. The radius dimension was imported to analyze the variation over land use associated with AOD patterns. The impact of different land use/cover types on the AOD and their relationship to air pollution. The results showed that: 1) In the study area, AOD is mainly concentrated in the oasis and population concentration area, and the optical thickness of the aerosol is gradually decreased from the center to the edge of the oasis in the southern mountain area. 2) Significant correlation between mean AOD and the landscape indicators (PD, ED, LSI and AI), the composition and spatial structure of the landscape affects the spatial distribution of AOD. 3) Fractal analysis showed that the density of cropland and salinity decreased from the center to the outer boundary so does the AOD. Cropland and saline land are major contributors to AOD in the watershed. 4) Fractal analysis showed that the AOD density declined from the center to the outer boundary so does saline land and cropland. Saline land and cropland area corresponding AOD density was significantly reduced from the center to the edge, saline land and cropland land of air pollution are main sources. The study enhance a better understand of the relationship between AOD and land use. The quantified effects of landscape structure variations on AOD patterns helped to better understand the effects of land use on AOD and they are important for policy making and land use planning. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:38
Main heading:Land use
Controlled terms:Adhesion - Aerosols - Air pollution - Air quality - Atmospheric aerosols - Ecology - Economics - Forestry - Fractals - Lakes - Landforms - LSI circuits - Maximum likelihood - Optical properties - Pixels - Pollution - Remote sensing - Saline water - Water pollution - Watersheds
Uncontrolled terms:Aerosol optical depths - Contribution analysis - Ebinur lakes - Fractal analysis - Spatial scale
Classification code:403 Urban and Regional Planning and Development - 443.1 Atmospheric Properties - 444 Water Resources - 444.1 Surface Water - 451 Air Pollution - 451.2 Air Pollution Control - 453 Water Pollution - 454.3 Ecology and Ecosystems - 481.1 Geology - 714.2 Semiconductor Devices and Integrated Circuits - 741.1 Light/Optics - 921 Mathematics - 922.1 Probability Theory - 951 Materials Science - 971 Social Sciences
DOI:10.11975/j.issn.1002-6819.2016.22.038
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 2>
Accession number:20164903093309
Title:Influence of modified biomass char on releases characteristics of volatiles during pyrolysis of cotton stalk
Authors:Liu, Huihui (1); Zou, Jun (1); Deng, Yong (1); Yang, Haiping (1); Wang, Xianhua (1); Chen, Hanping (1)
Author affiliation:(1) State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan; 430074, China
Corresponding author:Wang, Xianhua(wxhwhhy@sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:239-243
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The biomass char has an important influence on the release of volatile during the fast pyrolysis processes due to its complex structure features and the presence of inorganic minerals. Furthermore, as inherent catalysts, the large content of salts in biomass promotes the char to react with volatile. Thus this study aims to investigate the influence of char and inorganic salts on the volatile-char interactions. Experiments were conducted on a two-stage system with the same temperature of 500℃. Char pretreatments i.e. acid washing and salts (NaCl, KCl, MgCl<inf>2</inf>and FeCl<inf>3</inf>) impregnating were introduced. Volatile derived from cotton stalk pyrolysis got reaction under the presence of fresh char with different mass. The condensed bio-oil obtained from the pyrolysis with and without the catalysts (cotton stalk char) was characterized by the GC-MS (gas chromatograph-mass spectrometer) analyses. The non-condensed pyrolysis gas via the filter and drier was characterized by the GC. The results indicated that: with the increasing of the mass of cotton stalk char, its ability of promoting the secondary cracking of pyrolysis volatile became stronger. As a result, the liquid bio-oil yield decreased from 56.70% to 51.32%, while the yield of small molecular gases continued to increase from 17.88% to 22.13%. When the dosage of the cotton stalk char was 2.0 g, the highest gas yield of 22.1% was obtained. When the cotton stalk char was added in the pyrolysis, the acids, aldehydes and lipid content declined sharply. It is deduced that the cotton stalk char plays an inhibiting effect in the formation of them. At the same time, this inhibiting effect is conducive to the formation of more phenols. After deliming, semi-coke group structure will weaken the inhibition of the formation of acids in the volatile. Likewise, the capacity of phenolic enrichment is also reduced. The cotton stalk loaded with metal chloride enhanced the semi-coke's effects on the volatile catalytic cracking and restructuring, generating the gas with smaller molecule. When loaded with KCl, the capacity of cotton stalk char to the secondary catalysis of volatile was enhanced. Compared with the cotton stalk char with pickling, the gas yield was increased under the pyrolysis with the fresh cotton stalk. It is deduced that the metal ions play more significant effects on the volatile reaction during the catalytic reforming. The metal ions could promote the conversion of CO<inf>2</inf>and CH<inf>4</inf>. Meanwhile, Fe played the best promoting effect on the hydrogen yield, and the hydrogen content was up to 12.96%. When the cotton stalks char were loaded with the KCl and MgCl<inf>2</inf>, the content of CO contained in the non-condensed gas was increasing sharply. In the respect of the capacity of volatile cracking, the metal ions were stronger than simply increasing the quality of cotton stalk char in the lower catalytic section. The order of metal ions to the enrichment of phenolic was depicted as follows: K<sup>+</sup>>Na<sup>+</sup>>Fe<sup>2+</sup>>Mg<sup>2+</sup>. For deliming cotton stalk char, it also benefitted the forming of the phenol, although most metal ions had been removed. It is concluded that the skeleton structure of cotton stalk char plays an effect on the volatile cracking. The fresh cotton stalk inhibited the formation of furans. However, the cotton stalk char promoted the yield of furans to increase, reaching 14.26%. Picking and loading with different metal ions played a different role in the yield of bio-oil. The catalysis and the structure both worked in the pyrolysis. The presence of metal ions also promoted the decomposition of acids, esters and aldehydes. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:22
Main heading:Cotton
Controlled terms:Aldehydes - Aromatic compounds - Biofuels - Biomass - Carbon dioxide - Catalysis - Catalysts - Catalytic cracking - Catalytic reforming - Coke - Cracking (chemical) - Cracks - Filtration - Gases - Hydrogen production - Iron compounds - Metal ions - Metals - Molecules - Organic pollutants - Phenols - Pyrolysis - Salts - Straw
Uncontrolled terms:Biomass char - Fast pyrolysis process - Gas chromatograph mass spectrometers - Secondary cracking - Skeleton structure - Volatile - Volatile reactions - Volatile-char interactions
Classification code:522 Gas Fuels - 524 Solid Fuels - 531.1 Metallurgy - 802.2 Chemical Reactions - 802.3 Chemical Operations - 803 Chemical Agents and Basic Industrial Chemicals - 804 Chemical Products Generally - 821.4 Agricultural Products - 821.5 Agricultural Wastes - 931.3 Atomic and Molecular Physics
Numerical data indexing:Mass 2.00e-03kg, Percentage 1.30e+01%, Percentage 1.43e+01%, Percentage 1.79e+01% to 2.21e+01%, Percentage 2.21e+01%, Percentage 5.67e+01% to 5.13e+01%
DOI:10.11975/j.issn.1002-6819.2016.22.033
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 3>
Accession number:20164903093288
Title:Parameter optimization and experiment for cutting device of muskmelon grafting machine
Authors:Tian, Subo (1); Song, Chuancheng (1); Dong, Song (1); Wang, Ruili (1)
Author affiliation:(1) College of Engineering, Shenyang Agricultural University, Shenyang; 110866, China
Corresponding author:Wang, Ruili(rlwangsynd@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:86-92
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:At present, vegetable grafting techniques are extensively studied in the world, including Japan, South Korea, China and North America, and various types of grafting machines have been successfully developed. In China, Zhang Tiezhong, Gu Song and other researchers carried out the research work on cut-pasted grafting method in vegetable grafting machines. However, due to the complexity of grafting technology and the poor applicability of grafting machine, these machines are not widely used in China. Therefore, it is significant to develop the automatic grafting machine that can be suitable for agricultural production in Northeast China. In order to realize the automation of vegetable grafting machine, and solve the problem of low survival rate after cutting, the cutting device for muskmelon automatic grafting machine was designed and the working parameters of the device were optimized by using experimental methods in this study. A set of economical and suitable grafting machine was designed, which not only reduced the cost of design, but also ensured the efficiency and quality of the work. By rotating the cylinder to cut grafted seedling, the action was accurate and rapid, and at the same time effectively avoided the problem of the damage to the seedling during the cutting process. In the whole process, the device was stable, and the blade could be replaced only on a regular basis. The cutting efficiency was obviously improved. For the rotary cylinder cutting parts, the volume was very small, and the price was also relatively low. The whole set of equipment could be assembled and debugged under the existing conditions of the laboratory, and the design of the structure was simple and compact, which was easy to operate. In the case of ensuring the efficiency and quality of the work, the production cost of the equipment was successfully reduced. It is suitable to be popularized widely in China. The grafting seedlings for the typical muskmelon were selected as the research objects. Three variables were selected as the experimental factors, i.e. cutting angle, cutting radius and cutting height. Grafting fitting percentage of rootstock and scion was determined as the experimental index. Moreover, the single factor experiment and the quadratic regressive orthogonal experiment were conducted in order to determine the optimal technological parameters of cutting device. The single factor experiments studied the influence of cutting angle, cutting radius and cutting height on variation coefficient of cutting, respectively. According to the results of single factor experiments, the quadratic regressive orthogonal experiment was conducted, which selected 2 reasonable values within effective range as 2 levels. The optimal operating parameters of cutting device for muskmelon automatic grafting were determined by the experiment. For the cutting device, the optimized cutting angle was -9°, the optimized cutting radius was 39 mm and the optimized cutting height was 30 mm, and the grafting fitting percentage of rootstock and scion was 98%. The optimized parameters were proved to bring about the best cutting performance and meet the requirement of grafting survival rate. Under the conditions of the optimal operating parameters, the cutting device of muskmelon automatic grafting machine can meet the requirements of the design. Therefore, the cutting device can achieve automatic cutting, and the experimental results provide the important reference for developing vegetable automatic grafting machine. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Grafting (chemical)
Controlled terms:Agricultural machinery - Agriculture - Cost reduction - Costs - Cutting tools - Cylinders (shapes) - Efficiency - Experiments - Optimization - Vegetables
Uncontrolled terms:Agricultural productions - Muskmelon - Operating parameters - Orthogonal experiment - Parameter optimization - Single-factor experiments - Technological parameters - Variation coefficient
Classification code:603.2 Machine Tool Accessories - 802.2 Chemical Reactions - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 901.3 Engineering Research - 911 Cost and Value Engineering; Industrial Economics - 913.1 Production Engineering - 921.5 Optimization Techniques
Numerical data indexing:Percentage 9.80e+01%, Size 3.00e-02m, Size 3.90e-02m
DOI:10.11975/j.issn.1002-6819.2016.22.012
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 4>
Accession number:20164903093295
Title:Determination of soil moisture content by hyperspectral technology with CARS algorithm
Authors:Yu, Lei (1, 2); Zhu, Yaxing (1, 2); Hong, Yongsheng (1, 2); Xia, Tian (1, 2); Liu, Muxing (1, 2); Zhou, Yong (1, 2)
Author affiliation:(1) Key Laboratory for Geographical Process Analysis & Simulation, Central China Normal University, Wuhan; Hubei Province; 430079, China; (2) College of Urban & Environmental Science, Central China Normal University, Wuhan; 430079, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:138-145
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Hyperspectral technology is a popular method of predicting soil moisture content nowadays, however, soil spectra include quantities of invalid redundant information, which is a serious bottleneck problem that could lead higher complexity and lower accuracy of prediction model. In this study, 96 fluvo-aquic soil samples were collected at 0-20 cm depth in fields in Qianjiang city, Hubei province, China, and then the samples were pretreated by air-drying, grinding and sieving in a laboratory. Samples with different soil moisture content (SMC, mass fraction of 0-40%) were prepared. For each sample, hyperspectral reflectance was measured by an ASD Field Spec3 instrument. Outliers with abnormal data were removed by Monte Carlo cross validation method. After that, the raw spectral reflectance was processed by Savitzky-Golay smoothing method and continuum removal method. Then, spectra of samples were divided into 2 subsets by Kennard-Stone algorithm. One subset was a calibration set with 47 samples and the other subset was a prediction set with 30 samples. The wavelength variables sensitive (SWV) to SMC were selected from the full-spectrum by competitive adaptive reweighted sampling (CARS) method, and they were considered as an optimal variable set. The multivariate calibrations were performed with partial least squares regression by using the full-spectrum (F-PLSR) and the optimal variables (CARS-PLSR), respectively. The prediction accuracy was assessed by comparing determination coefficients (R<sup>2</sup>), root mean squared error (RMSE) and relative percent deviation (RPD). Results showed that the SMC greatly affected soil spectral reflectance. The soil spectral reflectance reduced with the SMC increase, and 4 soil moisture absorption peaks were obvious around 450, 1400, 1900 and 2200 nm. The peaks at 1400 and 1900 nm had the obvious redshift phenomenon. The SWV of samples with different moisture were obtained by CARS, and then an optimal variables set was generated including wavelengths of 443-449, 1408-1456, 1916-1943 and 2209-2225 nm. Using the CARS-PLSR model calibrated by the optimal variables, the predicting accuracy was improved compared to the F-PLSR model calibrated by the full-spectrum. The predicting accuracy of CARS-PLSR (R<sup>2</sup>, RMSE and RPD were 0.983, 0.0144 and 8.36, respectively) was higher than F-PLSR model (R<sup>2</sup>, RMSE and RPD were 0.976, 0.0166 and 7.21, respectively). Meanwhile, compared to F-PLSR model, the CARS-PLSR model reduced the variable numbers from 2001 to 101. In brief, the CARS-PLSR model not only enhanced the forecasting capability but also reduced the model complexity. Thus, this approach could facilitate the development of soil moisture sensor in field in the near future. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Moisture determination
Controlled terms:Algorithms - Calibration - Coherent scattering - Forecasting - Least squares approximations - Mean square error - Models - Moisture - Moisture control - Monte Carlo methods - Reflection - Soil moisture - Soils
Uncontrolled terms:Competitive adaptive reweighted sampling (CARS) - Determination coefficients - Fluvo-aquic soils - Hyper spectra - Hyperspectral reflectance - Partial least squares regression - Soil spectral reflectance - Variable selection
Classification code:483.1 Soils and Soil Mechanics - 711 Electromagnetic Waves - 921.6 Numerical Methods - 922.2 Mathematical Statistics - 944.2 Moisture Measurements
Numerical data indexing:Percentage 0.00e+00% to 4.00e+01%, Size 0.00e+00m to 2.00e-01m, Size 1.90e-06m, Size 2.20e-06m, Size 2.21e-06m to 2.23e-06m
DOI:10.11975/j.issn.1002-6819.2016.22.019
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 5>
Accession number:20164903093312
Title:Biterm topic model-based land use classification of moderate-resolution remote sensing images
Authors:Shao, Hua (1); Li, Yang (2, 3); Ding, Yuan (2, 3); Liu, Fengchen (1)
Author affiliation:(1) College of Geomatics Science and Technology, Nanjing Tech University, Nanjing; 211816, China; (2) Key Laboratory of VGE Ministry of Education, Nanjing Normal University, Nanjing; 210023, China; (3) Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing; 210023, China
Corresponding author:Li, Yang(skys1017@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:259-265
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Land Use/Land Cover type automatic interpretation based on remote sensing data is one of the key problems in many relevant fields. Although a large number of image classification algorithms have been developed, most of them can hardly meet the application requirements. Probabilistic topic models, represented by Latent Dirichlet Allocation (LDA) model, have showed a great success in the field of natural language processing and image processing, which can be used to effectively overcome the gap between low-level features and high-level semantic. In recent years it have also been introduced into remote sensing image analysis field, while most of the researches focused on the analysis of high-resolution remote sensing images. Nonetheless, the moderate-resolution remote sensing data is one of the main sources in Land Use/Land Cover type automatic interpretation. The study analyzed the problem faced by traditional probabilistic topic models in reduced resolution remote sensing image analyzing, and pointed out that low segmentation scale made the image objects small and contained fewer pixels. In fact the objects, which are regarded as image documents in current work, are sparse in moderate resolution remote sensing image. The scarcity led to poor stability when using the standard LDA model to infer the semantic of short documents. So Biterm Topic Model (BTM) showed the ability of inferring the semantic of sparse documents. BTM learns topics by directly modeling the generation of word co-occurrence patterns in the corpus, making the inference effective with the rich corpus-level information. By segmenting the remote sensing image into two scales and regarding the image objects at two levels as short documents and visual words respectively, BTM was introduced to the classification of moderate resolution remote sensing image. The co-occurrence of words denoted as biterm in a document were modeled in BTM extracted by setting a short context refers to a small, fixed-size window over a term sequence. However, the sequence pattern of image visual words is different from that in text. While the spatial relationship is the most important relationship among the visual words, the spatial neighborhood visual words can express the law of image of a certain land use/land cover type and is more aligned with the principle of the humans' observation process. So, it was proposed to use space adjacent visual word pairs as the observations in BTM called S-BTM to reduce the quantity of observation objects. Similar to LDA, it was intractable to exactly solve the parameters, Gibbs sampling was used to infer the topic of visual words. Advance Land Observing Satellite (ALOS) images were used in the experiment, whose spatial resolution was 10 m with 4 bands. LDA, BTM and S-BTM were compared in the classification of land use types. Both BTM and SBTM had higher classification accuracy than LDA. BTM and S-BTM reached the highest accuracy respectively when the visual dictionary size was 480 and 400. When the visual dictionary size was fixed at 400, S-BTM was more effective than BTM at different topic size and both reached the highest accuracy with 20 topics. S-BTM used 33562 biterms to infer the image documents' topic while the number in BTM was 167 455, which showed that S-BTM needed less computation. At last, when topic size was fixed at 20, both overall classification accuracy and Kappa's Coefficient showed that S-BTM achieved better results than LDA and BTM. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Image classification
Controlled terms:High level languages - Image analysis - Image processing - Image reconstruction - Image segmentation - Information retrieval systems - Land use - Linguistics - Models - Natural language processing systems - Remote sensing - Semantics - Space optics - Statistics
Uncontrolled terms:High resolution remote sensing images - Image classification algorithms - Latent dirichlet allocations - Moderate resolution - NAtural language processing - Probabilistic topic models - Remote sensing image classification - Topic Modeling
Classification code:403 Urban and Regional Planning and Development - 656.1 Space Flight - 723.1.1 Computer Programming Languages - 723.2 Data Processing and Image Processing - 903.3 Information Retrieval and Use - 922.2 Mathematical Statistics
Numerical data indexing:Size 1.00e+01m
DOI:10.11975/j.issn.1002-6819.2016.22.036
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 6>
Accession number:20164903093313
Title:Scene-level land use classification based on multi-features soft-probability cascading
Authors:Liu, Yueyan (1); Wang, Linyu (1); Zhang, Bin (1); Men, Jilin (1)
Author affiliation:(1) China University of Geosciences, Department of Land Resources Management, Wuhan; 430074, China
Corresponding author:Zhang, Bin(zhangbin@cug.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:266-272
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:High resolution remote sensing images (HRSI) provide abundant information on the textures and terrain structures of a scene. In recent years, scene classification methods based on mid-level feature learning have been increasingly used for the scene-level land use classification with high resolution remote sensing images. However, it is always a challenging task for effectively organizing and optimizing the spectral, texture and geometrical structure features in the field of land use classification at the scene level. Since the learning algorithm based on mid-level features can represent the low-level features (e.g., spectrum, textures and geometrical structures) of HRSI effectively, the scene level classification of land use can be easily achieved by the use of a classifier like support vector machine (SVM). Nevertheless, the mid-level feature descriptors are not discriminative enough, because the mid-level feature descriptors are learned by an unsupervised way. Meanwhile, the conventional approaches using this strategy consider merely the geometrical structure features, and neglect other meaningful low-level features of the images. In order to make the learned feature descriptors more discriminative and incorporate different low-level features better, in this work we proposed a method utilizing the vector-cascading model combining multi-features soft-probability to achieve the land use classification at the scene-level. Firstly, the local dense scale invariant feature transform (DSIFT), spectral features (SF) and local binary pattern (LBP) features were extracted as the low-level features of the images. The spectral features were obtained by calculating the color histogram of the images. Then, with regard to each type of low-level features, from each image a certain number of samples were selected randomly to be clustered by K-means algorithm to generate the dictionary. Secondly, based on the trained dictionary of the different features, the local DSIFT, spectral and LBP features were encoded individually with the locality-constraint linear coding (LLC) to get the sparse coefficients, with spatial pyramidal matching (SPM) model and the max-pooling used to obtain the mid-level feature descriptors. Finally, the mid-level feature descriptors of the three different low-level features were classified respectively by SVM classifier, and then the three different features soft-probabilities were calculated. After that, these feature soft-probabilities were vector-cascaded as the final feature representation of the image, and a second round of classification employing SVM classifier is then conducted for the final classification result. We validated our proposed method via the experiments using the public UC-Merced Land Use datasets. It can be concluded from experimental results that: 1) The overall accuracy of our proposed method reached to 88.6%, comparing with the traditional classification methods (i.e., ScSPM and LLC), the classification accuracy had been improved by 12.7% and 9.9% respectively; 2) By adjusting the size of dictionary and the number of training images, the classification results were proved to be more sensitive to the number of training images rather than the dictionary size. The average increase of classification accuracy was approximately 25.0% when the number of training images was increased to 60; 3) In contrast to the other scene classification methods which extracted the single low-level features, the proposed algorithm could more efficiently classify the indistinguishable land use types such as dense residential and medium residential, and it also could improve the accuracy of scene-level classification of land use considerably, with HRSI used. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Classification (of information)
Controlled terms:Binary images - Geometry - Housing - Image classification - Image matching - Image processing - Image reconstruction - Image retrieval - Land use - Learning algorithms - Probability - Remote sensing - Support vector machines - Vectors
Uncontrolled terms:Classification accuracy - Classification methods - Feature representation - High resolution - High resolution remote sensing images - Landuse classifications - Linear coding - Scale invariant feature transforms
Classification code:403 Urban and Regional Planning and Development - 403.1 Urban Planning and Development - 716.1 Information Theory and Signal Processing - 723 Computer Software, Data Handling and Applications - 723.2 Data Processing and Image Processing - 921 Mathematics - 921.1 Algebra - 922.1 Probability Theory
Numerical data indexing:Percentage 1.27e+01%, Percentage 2.50e+01%, Percentage 8.86e+01%, Percentage 9.90e+00%
DOI:10.11975/j.issn.1002-6819.2016.22.037
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 7>
Accession number:20164903093299
Title:Performances and mechanism of sand fixation and growth promotion based on modified hydrophilic polyurethane
Authors:Liang, Zhishui (1); Wu, Zhiren (2)
Author affiliation:(1) School of Civil Engineering, Southeast University, Nanjing; 210096, China; (2) School of Environment and Safety Engineering, Jiangsu University, Zhenjiang; 212013, China
Corresponding author:Wu, Zhiren(wwu5353@j-c-k.co.jp)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:171-177
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to study the mechanism of sand fixation and growth promotion by modified hydrophilic polyurethane (W-OHC), experiments both in laboratory and in field were conducted. In the laboratory experiment, the sand was taken from flowing sand dunes around Qinghai Lake. The permeability of W-OHC on sand was tested through the free infiltration method and the penetration thickness was gauged by a plastic ruler (precision accuracy of 2 mm). The performance of compressive strength of the sand-fixing layer was assessed in accordance with GB/T50123-1999 and the specimen was tested on a AG-X plus universal testing machine. As an important indication of vegetation germination and growth, the surface hardness was measured using a Yamanaka soil hardness tester. The wind tunnel test for wind erosion resistance evaluation was conducted in the Key Laboratory of Desert and Desertification in Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences. The spraying concentration of W-OHC was 3% and the wind with velocity of 10, 15, 20, 25 m/s lasted for 20, 15, 10, and 7 min, respectively. The property of freezing-thawing of the sand-fixing layer was evaluated. The freezing-thawing cycles was 50 times under -25℃ for 22 h and 25℃ for 2 h. Both the wind erosion resistance and freezing-thawing performances were assessed by compressive strength and surface hardness. Then the experiment of water retention was carried out in different spraying amounts and concentrations of W-OHC solution, and the rate of water content in sand-fixing layer was obtained. Finally, a field test in the flowing sand dunes around Qinghai Lake was carried out. The 2% and 3% W-OHC with spraying amount of 3 L/m<sup>2</sup>were compared. The results showed that: 1) W-OHC solution had good permeability on sand and a flexible sand fixation layer with porosity was formed when different concentrations of W-OHC solution were used. The penetration thickness decreased with the increase of W-OHC concentrations. When the concentration of W-OHC was about 3%, the penetration thickness was about 14 mm; 2) the compressive strength of sand-fixing layer increased with the increase of concentrations of W-HOC and it could reach as high as 1.2 MPa. The surface hardness presented an increasing trend with increasing concentrations of W-OHC and it could reach 23.2 mm. When the W-OHC concentration was 2% and the spraying amount was 3 L/m<sup>2</sup>, the surface of sand-fixing body showed some small cracks in the strong wind. While in the condition of 3% W-OHC, the sand-fixing layer could resist against the wind velocity of 25 m/s, and no obvious damage occurred on the surface in 7 min. In the freeze-thaw cycles of 50 times, the loss rates of compression strength and surface hardness were 10.2% and 6.5%, respectively; 3) A spatial network structure would be formed when W-OHC solution was solidified, and it would play an important role on water retention and growth promotion. The evaporation rate of water could decrease by more than 50% in the same conditions, the growth circle of vegetation would be extended in drought region, and thus the efficiency of vegetation restoration would be improved. The study will provide a strong support in both theory and application when W-OHC is widely applied to sand erosion control and growth promotion in desert. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:16
Main heading:Sand
Controlled terms:Compressive strength - Erosion - Freezing - Hardness - Hydrophilicity - Lakes - Landforms - Mechanical permeability - Mechanical properties - Polyurethanes - Soil testing - Thawing - Vegetation - Wind tunnels
Uncontrolled terms:Chinese Academy of Sciences - Evaporation rate of waters - Freezing thawing cycles - Growth promotion - Laboratory experiments - Universal testing machines - Vegetation restoration - Wind resistance
Classification code:481.1 Geology - 483.1 Soils and Soil Mechanics - 651.2 Wind Tunnels - 815.1.1 Organic Polymers - 951 Materials Science
Numerical data indexing:Percentage 1.02e+01%, Percentage 2.00e+00%, Percentage 3.00e+00%, Percentage 5.00e+01%, Percentage 6.50e+00%, Pressure 1.20e+06Pa, Size 2.00e-03m, Size 2.32e-02m, Time 4.20e+02s, Time 7.20e+03s, Time 7.92e+04s, Velocity 2.50e+01m/s
DOI:10.11975/j.issn.1002-6819.2016.22.023
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 8>
Accession number:20164903093287
Title:Design and experiment of root cutting device in garlic combine harvesting
Authors:Yu, Zhaoyang (1, 2); Hu, Zhichao (1, 2); Yang, Ke (1, 2); Peng, Baoliang (1, 2); Wu, Feng (1, 2); Xie, Huanxiong (1, 2)
Author affiliation:(1) Nanjing Research Institute of Agricultural Mechanization, Ministry of Agriculture, Nanjing; 210014, China; (2) Key Laboratory of Modern Agricultural Equipment, Ministry of Agriculture, Nanjing; 210014, China
Corresponding author:Hu, Zhichao(nfzhongzi@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:77-85
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The development of garlic harvest mechanization still lags relatively behind, restricting the development of China's garlic industry. In recent years, garlic combine harvester has been designed by Chinese research institutes, realizing the garlic digging, soil cleaning, stalk cutting and garlic bulb gathering. The main garlic combine harvester in the developed countries is bundling type or cutting seedling type harvester. The garlic combine harvester, which can finish the processes of root cutting, is few. Root cutting is the core technology of garlic harvest, and also the most difficult technical operation. The fresh garlic has thin and tender skin and different size, and its roots are mixed with sediment, which have a wide but disorderly distribution. Therefore, in the process of harvesting, how to ensure technical performance, such as high rate of one-time root clearance and low rate of bulb damage, has been a difficult technical problem of garlic root cutting mechanized operation. In view of the lower rate of root clearance and the higher damage ratio, a root cutting device of garlic combine harvester was designed, which realized the root cleaning and pre-cutting, the garlic sorting and arraying, and the second cutting of root. The root cutting device of garlic combine harvester consists of clamping delivery device, hairbrush roller, front revolving cutter, rank-alignment device and floating cutting device. The clamping delivery device carries out the clamping of garlic upper stalk and the transport. The clamping style of garlic is changed from chain-chain clamping to chain-board-hairbrush clamping. The rank-alignment device mainly achieves the functions of stalk fixation and garlic bulb alignment, which provides ancillary work to root cutting. The floating cutting device adopts the principle of floating rotary cutting to adapt different sizes of garlic bulb, which can realize shape cutting along the spherical trajectory under the garlic bulb. The spiral protection railings are installed outside the cutter of floating cutting device, which stay on the outside of cutter turning trajectory and keep the free state. This structure reduces the impact force when garlic bulb contacts the spiral railings, and thus solves the problems of hurting garlic bulb effectively. Combining theoretical analysis with experimental research, this paper has determined the key structure parameters and the key working parameters, and at the same time, synthetically optimized the main factors affecting root cutting quality. The results showed that the importance sequence of various factors affecting root cutting quality was as follows: conveying speed > clamping angle > cutter rotational speed. Under the 95% confidence level, conveying speed was highly significant for root cutting quality; clamping angle and cutter rotational speed were significant for root cutting quality. The optimum parameters were that the conveying speed was 1.05 m/s, the clamping angle was 79°, and the floating cutter rotational speed was 2200 r/min (The cutting linear velocity was 17.3 m/s). Under the conditions, the rate of cutting root was 96.1%, and the damage ratio of garlic bulb was 2.39%. The results provide the technical basis for the design and optimization of the root cutting device. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:22
Main heading:Harvesters
Controlled terms:Agricultural machinery - Alignment - Chains - Combines - Crops - Cutting - Design - Harvesting - Machine design - Railings - Speed
Uncontrolled terms:Damage rati - Design and optimization - Developed countries - Experimental research - Garlic - Root cuttings - Technical operations - Technical performance
Classification code:408.2 Structural Members and Shapes - 601 Mechanical Design - 601.1 Mechanical Devices - 602.1 Mechanical Drives - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
Numerical data indexing:Percentage 2.39e+00%, Percentage 9.50e+01%, Percentage 9.61e+01%, Rotational_Speed 2.20e+03RPM, Velocity 1.05e+00m/s, Velocity 1.73e+01m/s
DOI:10.11975/j.issn.1002-6819.2016.22.011
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 9>
Accession number:20164903093317
Title:Improving preservative effect of pork ham sausages by irradiation
Authors:He, Lichao (1); Ma, Sumin (2); Li, Chengliang (2); Peng, An (2); Yu, Xiang (3); Jin, Guofeng (2)
Author affiliation:(1) College of Food and Biotechnology, Wuhan Institute of Design and Sciences, Wuhan; 430205, China; (2) College of Food Science and Technology, Huazhong Agricultural University, Wuhan; 430070, China; (3) College of Life Science, Hubei Normal University, Huangshi; 435002, China
Corresponding author:Jin, Guofeng(jgf@mail.hzau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:296-302
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Irradiation is a kind of effective food sterilization technology, which can effectively inhibit and eliminate the pathogenic or spoilage microorganisms. Meat and meat products, due to their high level of nutrients, pH value (5.5-7.0) and high water activity, offer a congenial environment for the growth of bacteria. In recent years, the utilization of irradiation in ready to eat (RTE) meat products is gradually getting people's attention, because many of the ready-to-eat cooked meat products are sterilized by high temperature above 100℃, which may could cause the nutrition loss and flavor deterioration. Pork ham sausage is a kind of important cooked meat product, which has won good graces of many peoples. Thus, this study mainly used the γ-irradiation for pork ham sausages preservation to investigate the effect of different irradiation doses on the preservative effect of pork ham sausage, and finally chose a suitable irradiation dose for pork ham sausages. The study mainly irradiated the pork ham sausage using the γ ray of<sup>60</sup>Co at 1, 3, 5, 7 or 9 kGy, respectively. After irradiation, the pork ham sausages were stored immediately at 4℃ for 4 weeks, and the changes of lipid oxidation (TBARs), protein oxidation (carbonyl value), color, pH value, TVB-N content and total microbial counts were measured during the storage. Through analyzing these indices, the effect of different irradiation doses on pork ham sausage was discussed, and a suitable irradiation dose for the pork ham sausage was chosen. The results showed that irradiation could effectively decrease the oxidative stability of the lipid and protein of pork ham sausage, which consequently promote the lipid and protein oxidation of the pork ham sausage during storage at 4℃, and the effect was enhanced with irradiation dose increase. Due to the influence of irradiation on lipid and protein oxidation, the color of the samples was also affected by irradiation. But 1 kGy irradiation had no a significant effect on the color of pork ham sausage. 3 to 9 kGy irradiation could significantly decreased the a<sup>*</sup>value and increased the L<sup>*</sup>value compared to the control sample (P<0.05), and both of them decreased gradually with storage time increasing. The decrease rate of high dose irradiation groups was faster than that of low dose irradiation groups. The pH value of samples was not significantly affected by the irradiation dose (P>0.05) and also not changed significantly during the cold storage, which just changed within the range of 6.0-6.5. For all samples, the TVB-N content increased with storage time increase. But for irradiated samples, the increase rate was significantly lower than that of the control sample. And when the irradiation dose increased to 5 kGy, the inhibitory effect of irradiation on the TVB-N formation was not changed significantly with the continually increase of the irradiation dose. This result was very consistent with the microbiological analysis result. These results suggests that 5 kGy irradiation can play an effective inhibitory effect on the microorganisms of pork ham sausages, and will be a very promising ham sausage preservation technology. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Meats
Controlled terms:Biological radiation effects - Cold storage - Color - Gamma rays - Irradiation - Lipids - Microorganisms - Oxidation - pH - Proteins - Radiation - Spoilage
Uncontrolled terms:Growth of bacteria - Ham sausage - Irradiated samples - Low dose irradiation - Microbiological analysis - Oxidative stability - Preservation technologies - Spoilage microorganisms
Classification code:461.2 Biological Materials and Tissue Engineering - 461.9 Biology - 644.3 Refrigeration Equipment and Components - 741.1 Light/Optics - 801.1 Chemistry, General - 802.2 Chemical Reactions - 804.1 Organic Compounds - 822.3 Food Products - 931.3 Atomic and Molecular Physics
Numerical data indexing:Absorbed_Dose 1.00e+03Gy, Absorbed_Dose 3.00e+03Gy to 9.00e+03Gy, Absorbed_Dose 5.00e+03Gy, Absorbed_Dose 9.00e+03Gy, Age 7.67e-02yr
DOI:10.11975/j.issn.1002-6819.2016.22.041
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 10>
Accession number:20164903093277
Title:Analysis on satisfied degree and advantage degree of agricultural crop straw feed utilization in China
Authors:Chu, Tianshu (1); Yang, Zengling (1); Han, Lujia (1)
Author affiliation:(1) College of Engineering, China Agricultural University, Beijing; 100083, China
Corresponding author:Yang, Zengling(yangzengling@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:1-9
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:As an agricultural country, China produces a great deal of agricultural straw every year. Agricultural crop straw feed utilization is one of the agricultural crop straw comprehensive utilization ways, which guarantees the development of save-grain animal husbandry and provides enough roughage for ruminant, such as cow, beef cattle and mutton sheep. So it is important to research on development status of agricultural crop straw feed utilization in China. In this paper, thirty-one provinces were selected as research objects, firstly, estimation of amount and demand of agricultural crop straw feed utilization of these provinces. The amount of agricultural straw feed utilization was estimated by using the six crop yield, that are corn, wheat, rice, bean, tuber and peanut, multiplied the ratio of straw to grain and productivity of collectable and usable straw. Then, adding the amount of crop straw feed together and multiplied the ratio of China's agricultural crop straw feed utilization. The crop yield data came from China Statistical Yearbook 2009-2014. The demand of agricultural crop straw feed was estimated by using the amount of cow, beef cattle and mutton sheep multiplied feeding structure, feeding amount of agricultural crop straw feed and feeding period. Then, adding the demand of agricultural straw feed together. The ruminant amount data came from China Rural Statistical Yearbook 2009-2014, China Animal Industry Yearbook 2009-2013 and China Animal Husbandry and Veterinary Yearbook 2014. So divided the amount of agricultural crop straw feed utilization by the demand of agricultural crop straw feed, it got the satisfied degree of agricultural crop straw feed. The advantage degree meant that the amount and demand of agricultural crop straw feed of one province had an advantage, compared with others. The results showed that: 1) From 2008 to 2013, amount and demand of agricultural crop straw feed utilization of China showed an increasing trend. In 2013|, the amount of agricultural crop straw feed utilization was 168.95 million tons and the demand of agricultural crop straw feed was 125.68 million tons. The Northeast China, Huang-Huai-Hai Region, Middle-Lower Yangtze Region, Inner Mongolia and Sichuan were the main area of amount of agricultural crop straw feed utilization. The Northwest China, Huang-Huai-Hai Region, Southwest China, Inner Mongolia, Sichuan, Tibet, Gansu and Xinjiang were the main area of demand of agricultural crop straw feed. 2) From 2008 to 2013, the satisfied degree of agricultural crop straw feed of China also showed an increasing trend. In 2013, the satisfied degree of agricultural crop straw feed of China was 134.43%, which meant the agricultural crop straw feed utilization met the demand of ruminant. The East China mainly met the demand, such as Jiangsu, Zhejiang, Anhui, Shanghai and Heilongjiang. But the West China was not, such as Ningxia, Xinjiang, Gansu, Qinghai and Tibet. And the advantage degree of agricultural crop straw feed utilization of Huang-Huai-Hai Region, the Northeast China, Inner Mongolia and Sichuan were higher than others. 3) The Huang-Huai-Hai Region, the Northeast China, Inner Mongolia and Sichuan were the core region of save-grain animal husbandry. Finally, the amount, demand, satisfied degree and advantage degree of agricultural crop straw feed provided the basic information about the development status of agricultural crop straw feed utilization in the thirty-one provinces. What's more, it contributed to the development of save-grain animal husbandry in China. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:18
Main heading:Crops
Controlled terms:Agriculture - Animals - Feeding - Grain (agricultural product) - Meats - Straw
Uncontrolled terms:Advantage degree - Agricultural crops - Agricultural straw - Comprehensive utilizations - Development status - Feeding structures - Ruminant - Satisfied degree
Classification code:691.2 Materials Handling Methods - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 822.3 Food Products
Numerical data indexing:Percentage 1.34e+02%
DOI:10.11975/j.issn.1002-6819.2016.22.001
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 11>
Accession number:20164903093301
Title:Inversion of photosynthetically active radiation based on GF-1 image by dark object method
Authors:Wang, Limin (1); Yang, Lingbo (1); Liu, Jia (1); Yang, Fugang (1); Shao, Jie (1); Yao, Baomin (1)
Author affiliation:(1) Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing; 100081, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:184-191
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Photosynthetically active radiation (PAR) is an important influential factor of vegetation photosynthesis, and the study on its size and spatial distribution has important significance in many fields such as ecosystem study, agriculture monitoring, and ground-air energy exchange. To meet the demand of GF-1 satellite PAR remote sensing inversion, the paper establishes an atmospheric parameter look-up table (LUT), utilizes major atmospheric parameters, such as linear relation of reflectivity between blue band and red band of dark dense vegetation as well as inversed aerosol optical depth (AOD), and finally successfully inverses the ground PAR based on atmospheric radiation transfer model. The paper also conducts accuracy verification on the inversion result by using actually measured ground PAR. Dark dense vegetation algorithm uses the fixed linear relation of reflectivity between blue band and red band of dark dense vegetation in the GF-1 images to inverse the AOD. Identification of dark dense vegetation is mainly based on NDVI (normal difference vegetation index) values. Using typical vegetation spectral library provided by the USGS (United States Geological Survey), and based on GF-1 spectral response function convolution, the surface reflectivity of the vegetation in various wavebands were obtained, the proportionality coefficient of ground surface reflectivity between red band and blue band was analyzed, and finally obtains the proportionality coefficient of 1.7977 with the intercept of 0.0034, and the correlation coefficient of 0.9826. By taking linear relation of vegetation reflectivity between red band and blue band as constraint condition, and combined with radiation transfer equation, the aerosol and atmospheric parameter LUT is established and the AOD is inversed based on the LUT. Meanwhile, the spatial interpolation is made by using the property of continuity of AOD to acquire the AOD of the overall study area. After the inversion of AOD, atmospheric parameters such as atmospheric transmittance and hemisphere albedo are calculated. Finally ground solar radiation intensities in red, green and blue wave band of GF-1 satellite image are calculated. By studying the relation between ground surface solar radiation intensities of blue, green and red waveband in GF-1 satellite image and overall 400-700 nm PAR value, the paper has worked out the 3 conversion coefficients of 0.09156, 0.09951, and 0.1007 respectively, and thus realized the inversion from the ground solar radiation intensity of 3 discrete wavebands to PAR. The study selects 12 pieces of GF-1 effective data from April 2014 to December 2014 in the study area in Yucheng City, Shandong Province to inverse AOD and PAR, and verifies the results by comparing them with actually measured data in Yucheng experimental station of Chinese Ecosystem Research Network (CERN). The result shows that the overall accuracy of PAR has reached 95.77% with the average absolute error of 11.36 W/m<sup>2</sup>and the average error less than 5%, indicating the correctness and precision of the method proposed by this paper, and also indicating the feasibility of PAR inversion by using GF-1 satellite images. The study also shows that the spatial distribution of PAR has significant correlation with AOD, and the higher the AOD is, the lower the PAR will be. By changing proportionality coefficient of vegetation reflectivity between red band and blue band, the study has found that when the coefficient value is approximately 1.5-2.1, its impact on PAR inversion accuracy is small. It is suggested to set the value to approximately 1.8 in order to achieve high accuracy. The method proposed by this paper can accurately inverse clear sky PAR with only original GF-1 satellite images without additional support data. This method is featured with simple production process and easy to be applied in the PAR operation inversion. It can provide important early-stage product data support for crop production estimation based on PAR in agricultural remote sensing monitoring practice. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:35
Main heading:Vegetation
Controlled terms:Aerosols - Agriculture - Atmospheric aerosols - Atmospheric radiation - Cultivation - Ecology - Ecosystems - Heat radiation - Inverse problems - Optical properties - Radiation - Reflection - Remote sensing - Satellites - Solar radiation - Spatial distribution - Spectrum analysis - Table lookup
Uncontrolled terms:Aerosol optical depths - Agricultural remote sensing - Atmospheric radiation transfer model - Dark dense vegetation algorithms - GF-1 - Photosynthetically active radiation - Radiation transfer equations - United states geological surveys
Classification code:443.1 Atmospheric Properties - 454.3 Ecology and Ecosystems - 641.2 Heat Transfer - 655.2 Satellites - 657.1 Solar Energy and Phenomena - 723.1 Computer Programming - 741.1 Light/Optics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.3 Agricultural Methods - 921 Mathematics
Numerical data indexing:Percentage 5.00e+00%, Percentage 9.58e+01%, Size 4.00e-07m to 7.00e-07m, Surface_Power_Density 1.14e+01W/m2
DOI:10.11975/j.issn.1002-6819.2016.22.025
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 12>
Accession number:20164903093284
Title:Influence factor analysis of mechanical damage on corn ear picking
Authors:Geng, Aijun (1, 2); Yang, Jianning (1); Zhang, Ji (1); Zhang, Zhilong (1); Yang, Qiyong (1); Li, Ruxin (1)
Author affiliation:(1) College of Mechanical and Electrical Engineering, Shandong Agricultural University, Tai'an; 271000, China; (2) Shandong Provincial Key Laboratory of Horticultural Machineries and Equipments, Tai'an; 271000, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:56-62
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to study the damage and mechanism of corn during corn ear picking, this paper analyzed the force of corn ear when picking corn ear, and then found that there were 3 kinds of forces working on corn ear, which were the reacting force, the frictional forces of stripping roller and the force of stripping roller rib, and caused the corn ear damage with different forms. This paper made the mathematical model of forces, and analyzed their change law and their influence on the damage of corn ear. With the rising of corn ear diameter, the reacting force, the frictional forces of stripping roller and the seed loss increased. The experiments of corn ear picking were carried out on test bed. The results showed that the damage of corn seed increased as the length of corn ear was greater than 175 mm. Because with the increase of the corn ear, the center of gravity for corn ears was upward and the corn ear swing increased when it was picked, the probability of collision increased. The rate of corn damage descended as the rotating speed of stripping roller changed from 650 to 800 r/min. When the rotating speed of stripping roller was more than 800 r/min, the corn damage increased significantly. When the rotation of stripping roller became faster, the down velocity of corn ears became bigger, the impact between corn ear and stripping roller increased, and the corn damage rose. Besides, the reduction of friction between the maize straw and stripping roller was another reason for the increasing of corn damage. The corn seed loss rate decreased and then increased as the rotating speed of stripping roller changed from 650 to 750 r/min, and the corn seed loss rate decreased again as the rotating speed of stripping roller changed from 750 to 850 r/min. Because when the rotation of stripping roller became faster, the corn ear down speed became bigger, the impact between the corn ear and stripping roller increased. The corn damage and seed loss decreased and then increased as the stripping roller clearance changed from 8 to 15 mm. The corn damage and seed loss were the minimum when the stripping roller clearance was 10 mm, and then with the clearance of stripping roller increasing, the corn damage and seed loss ascended, which was consistent with the result of theoretical analysis. And the mechanical damage form of corn usually included corn nibbled, corn impacted, corn extruded and broken corn ear. The process of corn ear picking was recorded with the high-speed camera and the movement of corn ear was analyzed. The results indicated that the moving velocity of corn ear had no effect on corn damage. It was also observed from the record that the moving state of corn ear picking had 3 types: first, corn ear was picked smoothly and entered the conveyer device; second, corn ear bounced; third, corn ear picking became difficult or corn ear contacting stripping roller for a long time. And the corn ear damage became more serious with the increasing of the contacting time between corn ear and stripping roller. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Rollers (machine components)
Controlled terms:Agricultural machinery - Crops - Friction - High speed cameras - High speed photography - Models - Reinforcement - Rotating machinery - Speed
Uncontrolled terms:Center of gravity - Corn ear picking - Force analysis - Frictional forces - Influence factor analysis - Mechanical damages - Moving velocity - Rotating speed
Classification code:601.1 Mechanical Devices - 601.2 Machine Components - 742.1 Photography - 742.2 Photographic Equipment - 821.1 Agricultural Machinery and Equipment - 821.4 Agricultural Products - 951 Materials Science
Numerical data indexing:Rotational_Speed 6.50e+02RPM to 7.50e+02RPM, Rotational_Speed 6.50e+02RPM to 8.00e+02RPM, Rotational_Speed 7.50e+02RPM to 8.50e+02RPM, Rotational_Speed 8.00e+02RPM, Size 1.00e-02m, Size 1.75e-01m, Size 8.00e-03m to 1.50e-02m
DOI:10.11975/j.issn.1002-6819.2016.22.008
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 13>
Accession number:20164903093305
Title:Temperature variation, heat storage and heat release characteristics of soil wall in solar greenhouse
Authors:Shi, Yuliang (1, 5); Wang, Xiufeng (1, 2); Wei, Min (1, 2); Li, Qingming (1, 2); Liu, Fusheng (3); Hou, Jialin (4)
Author affiliation:(1) College of Horticulture Science and Engineering, Shandong Agricultural University, Taian; 271018, China; (2) Scientific Observing and Experimental Station of Environment Controlled Agricultural Engineering in Huang-Huai-Hai Region, Ministry of Agriculture, Taian; 271018, China; (3) College of Water Conservancy and Civil Engineering, Shandong Agricultural University, Taian; 271018, China; (4) College of Mechanical and Electronic Engineering, Shandong Agricultural University, Taian; 271018, China; (5) College of Horticulture, Qingdao Agricultural University, Qingdao; 266109, China
Corresponding author:Wang, Xiufeng(xfwang@sdau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:214-221
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The solar greenhouse of soil wall, which has the advantages of good heat storage and low construction cost, is widely used in China. At present, the study on the heat storage and heat release performance of soil wall is an important hot spot, which can provide the theoretical basis for the simplification and thickness optimization of soil wall. In the paper, the sunken soil wall greenhouse serves as the research object in Taian, Shandong Province, China. The length is 50 m and the width is 10 m. The top and bottom thicknesses of the soil wall are 1.47 and 3.0 m, respectively. In order to get a better analysis of the heat storage and heat release performance of soil wall, the five testing layers of temperature were arranged in the north wall of greenhouse. The testing period was from Dec. 1st, 2014 to Jan. 30th, 2015. The outdoor weather conditions, indoor air temperature and interior wall temperature were monitored during the testing period. The variation regularity of the indoor and interior wall temperature was analyzed according to the monitoring data in the coldest season (from Dec. 20th, 2014 to Jan. 19th, 2015). The results showed that the testing point temperature of wall surface and interior wall (0.1-0.6 m) presented periodicity variation regularity with the indoor temperature variation in greenhouse, and temperature fluctuation amplitude reduced gradually, at the same time the phase was lags obviously along the wall thickness direction. Moreover, it showed that the interior wall (0-0.6 m) could be considered as the heat storage and heat release body in the soil wall. The heat storage body in the soil wall had large temperature fluctuation, which could be used for storing heat during daytime and releasing heat into the solar greenhouse during night. Besides that, the temperature fluctuation of testing point behind 0.7 m tended to the stabilization, which was in the process of the steady-state heat transfer from the soil wall to outdoors and could be considered as temperature stabilization body in the soil wall. The average temperatures of the testing points of 0.7 m from the first layer to the fifth layer were 8, 10.45, 12.79, 15.19 and 17.42℃ respectively, and the testing points behind 0.8 m were also the same temperature change regularity. It showed that the equidistance testing point between interior wall surface and interior soil wall on each testing layer had the same regularity of temperature change, that was, increased regularly with the thickening of the soil wall. In order to evaluate the performance of the heat storage and the heat release of soil wall better, the weighted average values of heat storage of all five testing layers were calculated, which were then converted to the heat storage and heat release relative to unit wall area so as to calculate the corresponding heat storage and heat release of the 0.6 m soil wall during a whole day. On the basis of the heat storage and the heat release results, the average efficiency of heat release for the soil wall during the coldest season period was calculated. The result showed that the average efficiency of heat release was 43% for solar greenhouse of the soil wall, which could release 43% of the heat storage of soil wall during the day to improve the thermal environment of the greenhouse nighttime. The study on heat storage calculation, heat release calculation and efficiency evaluation of average heat release will not only provide guidance for structural optimization and heat load calculation of greenhouse, but also provide theoretical basis for the simplification technology of soil wall greenhouse in different region of china. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:21
Main heading:Soil testing
Controlled terms:Digital storage - Efficiency - Environmental regulations - Greenhouses - Heat storage - Heat transfer - Soils - Solar heating - Stabilization - Structural optimization - Temperature - Temperature distribution
Uncontrolled terms:Heat load calculations - Heat release - Heat release characteristic - Outdoor weather conditions - Simplification technology - Steady-state heat transfer - Temperature fluctuation - Temperature stabilization
Classification code:454.2 Environmental Impact and Protection - 483.1 Soils and Soil Mechanics - 641.1 Thermodynamics - 641.2 Heat Transfer - 657.1 Solar Energy and Phenomena - 722.1 Data Storage, Equipment and Techniques - 821.6 Farm Buildings and Other Structures - 913.1 Production Engineering - 921.5 Optimization Techniques
Numerical data indexing:Percentage 4.30e+01%, Size 0.00e+00m to 6.00e-01m, Size 1.00e+01m, Size 1.00e-01m to 6.00e-01m, Size 3.00e+00m, Size 5.00e+01m, Size 6.00e-01m, Size 7.00e-01m, Size 8.00e-01m
DOI:10.11975/j.issn.1002-6819.2016.22.029
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 14>
Accession number:20164903093290
Title:Model and PID algorithm realization of nutrient solution control based on two-step fertilizer mixing system
Authors:Li, Li (1); Wang, Junheng (1); Meng, Fanjia (1); Mu, Yonghang (2); Yuan, Hongbo (3); Wang, Haihua (1); Sigrimis, N. (4)
Author affiliation:(1) Key Laboratory on Modern Precision Agriculture System Integration Research of Ministry of Education, China Agricultural University, Beijing; 100083, China; (2) Key Laboratory of Agricultural Information Acquisition Technology, Ministry of Agriculture, China Agricultural University, Beijing; 100083, China; (3) College of Mechanical and Electrical Engineering, Agricultural University of Hebei, Baoding; 071001, China; (4) Department of Agricultural Engineering, Agricultural University of Athens, Athens; 11855, Greece
Corresponding author:Wang, Haihua(whaihua@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:100-106
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Closed cultivation is a new type of cultivation model, which is widely used in solar greenhouse, and it uses EC as the performance index of the regulation process of nutrient solution. In the study, a dynamic analysis was conducted on the regulation process of closed culture nutrient solution with two-step mixed fertilizer characteristics. PID control algorithm was used to control the regulation process of the nutrient solution, and the effects of 6 factors on control process were analyzed through comparative experiment. The results showed that it was difficult to use a precise model to characterize the fertilizer mixing process, since the output liquid flow rate, the fertilizer concentration and the PID parameters had great influence on the control effect of the two-step mixed fertilizer system. Experiments were carried out to find the effect of different output liquid flow rates, fertilizer concentration and the PID parameters, on PID control model. The results were obtained using the fixed variable method and orthogonal tests, under the target electrical conductivity (EC) of 2.3. The experimental results showed that the time of the system decreased with the decrease of the output liquid flow rate or the increase of the fertilizer concentration. Duration of system oscillation and overshoot amount increased with the decrease of the output liquid flow rate or the increase of the fertilizer concentration. Keeping the fertilizer concentration and the PID parameters (obtained under the condition that the output liquid flow rate was 4 m<sup>3</sup>/h and the fertilizer concentration were 4 channels) unchanged, and the target EC of 2.3, the duration of system oscillation was changed from 15 s to 125 s while the output liquid flow rate was changed from 10 m<sup>3</sup>/h to 4 m<sup>3</sup>/h, and, the stable time was changed from 180 s to 205 s and the overshoot was changed from 1% to 20%. Keeping the output liquid flow rate and the PID parameters (obtained under the condition that the output liquid flow rate was 4 m<sup>3</sup>/h and the fertilizer concentration were 4 channels) unchanged and the target EC of 2.3, the duration of system oscillation was changed from 40 s to 125 s while the number of the fertilizer opening channel was changed from 1 channel to 4 channels, the stable time was changed from 255 s to 205 s, and the overshoot was changed from 3% to 20%. According to the different executive agencies and environmental factors, it was necessary to adjust the PID parameter of the system to achieve better control effect. The closed cultivation system ran with high efficiency and stability using the adjusted PID parameters. According to the test results and analysis, the optimal output liquid flow rate and the concentration of the fertilizer solution in closed culture system with two-step mixed fertilizer were 6 m<sup>3</sup>/h and 200 g/L, respectively. Under this condition, the PID control parameters were adjusted, and the stability time of the system was 100 s, the overshoot was 3%, and the duration of oscillation was 25 s. In summary, the nutrient solution of the closed type cultivation system with double mixed fertilizer could be regulated by the PID algorithm to achieve stable and efficient operation, which provided a reference for the regulation. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Process control
Controlled terms:Algorithms - Fertilizers - Flow rate - Greenhouses - Liquids - Mixing - Models - Nutrients - Oscillating flow - Parameter estimation - Solar heating - System stability - Three term control systems
Uncontrolled terms:Closed culture systems - Closed systems - Comparative experiments - Electrical conductivity - Environmental factors - Mixing system - Nutrient solution - Solar greenhouse
Classification code:631 Fluid Flow - 631.1 Fluid Flow, General - 657.1 Solar Energy and Phenomena - 731.1 Control Systems - 802.3 Chemical Operations - 804 Chemical Products Generally - 821.6 Farm Buildings and Other Structures - 961 Systems Science
Numerical data indexing:Mass_Density 2.00e+02kg/m3, Percentage 1.00e+00% to 2.00e+01%, Percentage 3.00e+00% to 2.00e+01%, Percentage 3.00e+00%, Time 1.00e+02s, Time 1.50e+01s to 1.25e+02s, Time 1.80e+02s to 2.05e+02s, Time 2.50e+01s, Time 2.55e+02s to 2.05e+02s, Time 4.00e+01s to 1.25e+02s
DOI:10.11975/j.issn.1002-6819.2016.22.014
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 15>
Accession number:20164903093318
Title:Biological properties of bacteriophages and biocontrol of staphylococcus aureus in foods
Authors:Long, Men (1, 2); Zhan, Ge (2); Jin, Shuangchao (2); Zhou, Hui (2); Du, Qingfei (2); Wang, Ran (1)
Author affiliation:(1) Institute of Food Safety and Inspection, Jiangsu Academy of Agriculture Sciences, Nanjing Agricultural University Collaborative Innovation Center, Nanjing; 210014, China; (2) College of Biological and Food Engineering, Chuzhou College, Chuzhou; 239000, China
Corresponding author:Wang, Ran(wangran2001@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:303-308
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Staphylococcus aureus, as one of the most common food-borne pathogens, is related to the health, safety in the food industry and fields of medicine and it can be transmitted to humans and animals through the food. Although many foods can serve as vehicles, Staphylococcus aureus is often isolated from ready-to-eat (RTE) foods, such as milk,ham and cabbage. RTE foods have been implicated in most of the major listeriosis outbreaks in the last 30 years. Of particular concern is the fact that they are consumed directly, without a final bactericidal processing step. Since the preservation methods applicable to minimally processed RTE foods often seem to be insufficient to prevent Staphylococcus aureus contamination and growth, new strategies to combat this opportunistic pathogen in foods are needed. Bacteriophages are natural enemies of bacterias and are suitable candidates for the environmentally friendly biocontrol of these pathogens. Using bacteriophages as a tool to the control of pathogens is a complementary to antibiotic therapy. We have isolated a lytic bacteriophage, broad-host-range phages, designated JS25 (Morphologic analysis of JS25 revealed that it was closely related to other Myoviridae phages infecting Staphylococcus species.), from sewage effluent on a dairy farm in Jiangsu, using as a biocontrol agent against Staphylococcus aureus infections. In a comprehensive set of experiments, we evaluated thermal and pH stability,studied phage adsorption and determined the optimal multiplicity of infection. Then, we determined the latent period and burst size of JS25 bacteriophages by one-step growth. Last, we evaluated the virulent, broad-host-range phages JS25 bacteriophages for control of Staphylococcus aureus in different RTE foods (ham, dried meat, fresh milk, cabbage) known to frequently carry the pathogens and analyzed its stablity during storage. Food samples were spiked with bacteria (1×10<sup>3</sup>CFU/g) respectively, with phage added thereafter (1×10<sup>8</sup>PFU/g), and then samples were stored at 4 and 20℃ separately for 12 days. The results showed that its latent period and average burst size during stable period were approximately 20 min and 24.55 PFU/cell, respectively. Optimum pH range for JS25 phage was between 6 and 9. However, a treatment of 80℃ for 40 min completely inactivated the phage. Thus, JS25 was stable below 60℃. The adsorption rate of JS25 showed at 20 min post-infection, approximately 100% of the JS25 was adsorbed to the host cells. The bacteriolytic activity of JS25 at a multiplicity infection (MOI) 0.1 indicated its optimum efficiency for reducing bacterial growth. Also, we can see phage JS25 was of high stability in ham, dried and fresh milk during storage at 4 and 20℃. JS25 titer dropped 0.48 logs and 0.98 logs only in cabbage storage at 4 and 20℃, respectively. Therefore, the added phages retained most of their infectivity during storage in foods storage at 4 and 20℃. For RTE foods, such as dried meat, fresh milk and cabbage, biological control effect of phage against staphylococcus aureus was higher with the increasing of phage initial titer, and was different among different RTE foods. For fresh milk and cabbage, the optimum phage titer was 10<sup>8</sup>and 10<sup>10</sup>PFU/g, respectively, while for the ham and dried meat, whose phage titer was 10<sup>9</sup>PFU/g. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Food microbiology
Controlled terms:Accident prevention - Bacteria - Bacteriophages - Biocontrol - Convergence of numerical methods - Food safety - Meats - Pathogens - pH effects - Sewage
Uncontrolled terms:Bacteriolytic activity - Biological properties - Morphologic analysis - Multiplicity of infections - Preservation methods - Ready-to-eat foods - Staphylococcus aureus - Titer
Classification code:452.1 Sewage - 461 Bioengineering and Biology - 801.1 Chemistry, General - 822.3 Food Products - 914.1 Accidents and Accident Prevention - 921.6 Numerical Methods
Numerical data indexing:Age 3.00e+01yr, Age 3.29e-02yr, Percentage 1.00e+02%, Time 1.20e+03s, Time 2.40e+03s
DOI:10.11975/j.issn.1002-6819.2016.22.042
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 16>
Accession number:20164903093279
Title:Theoretical model analysis and test of screw conveyor for rubbing and breaking corn straw
Authors:Wulantuya (1); Wang, Chunguang (1); Qi, Shaohua (1); Wang, Xiaorong (1); Wang, Haichao (1); Wang, Jinlian (1)
Author affiliation:(1) College of Mechanical and Electrical Engineering of Inner Mongolia Agricultural University, Hohhot; 010018, China
Corresponding author:Wang, Chunguang(jdwcg@imau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:18-26
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Screw conveyor is widely used in the crop harvest and processing of agricultural fiber materials, for the screw conveyor has the advantages of simple structure, reliable work, low cost, easy operation management, good tightness, less pollution to the environment, and so on. However, there are some problems such as low productivity and high power consumption in the process of conveying the agricultural fiber materials, because the theoretical study about the screw conveying process of fiber material is not perfect enough and conveying mechanism is not clear. In order to solve these problems, the theoretical analysis of conveying process about screw conveyor was carried out. Firstly, corn straw was rubbed and broken, some hypotheses were made about its movement condition, and its screw conveying model was built. Based on the plug flow theory, non-plug solid conveying theory and Triaminic non-plug conveying theory, the motion and stress of corn straw micro-unit in the screw groove were analyzed. Continuity equation and kinematics equation were built and then solved. The model of the pressure on material under different working conditions was obtained. On this basis, the productivity model and power consumption model were built. The variation of the pressure on material, the productivity and the power consumption with the pitch, rotational speed and feeding quantity was analyzed. The experimental platform of screw conveyor that can accurately measure the axial thrust and power on line was developed by the research group through using loop force measuring sensor, torque speed sensor and computer. The parameter of the experimental platform was that the conveying gap length was 2500 mm, the diameter of the screw blade was 250 mm, the diameter of the center axis was 60 mm, the pitch was 160, 200, 250 and 300 mm respectively, and the space between the screw blade and the casing was 5-8 mm. The samples were from the corn stalks crushed by the 9R-40 type crusher, which were less than 180 mm long and 2-8 mm wide, and had 52.87% moisture content. The impact of pitch, rotational speed and feeding quantity on axial thrust, productivity, and power consumption was studied in the experiment. The results showed that: 1) When the rotational speed was 58 r/min and the feeding quantity was 30 kg/min, the pressure decreased, the productivity increased and the power consumption decreased firstly and then increased with the pitch increasing. 2) When the pitch was 250 mm and the feeding quantity was 30 kg/min, the pressure and the power consumption increased, and the productivity increased firstly and then decreased with the rotational speed increasing. 3) When the pitch was 250 mm and the rotational speed was 58 r/min, the pressure, the productivity, and the power consumption increased with the increase of feeding quantity. Finally, the contrastive analysis was made between the theoretic and the experimental value. The results showed that when the pitch was 160-300 mm, the rotational speed was 58-148 r/min, and the feeding quantity was 10-70 kg/min, the relative error of theoretic and the experimental results of the pressure on material, the productivity and the power consumption was within 14%, 11% and 11%, respectively. The model of the pressure on material, productivity model and power consumption model were modified by the test data of axial thrust, productivity and power consumption, respectively, the results show that: when the pitch was 160-300 mm, the rotational speed was 58-148 r/min, and the feeding quantity was 10-70 kg/min, the relative error of the theoretic value and the experimental value of pressure on material was within 11.7%, 8.6% and 5.9%, respectively; the relative error of the theoretic value and the experimental value of productivity was within 5.1%, 6.9% and 5.4%, respectively; and the relative error of the theoretic value and the experimental value of power consumption was within 5.9%, 5.8% and 5.2%, respectively. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Screws
Controlled terms:Agricultural machinery - Agriculture - Conveyors - Crops - Electric power utilization - Errors - Feeding - Models - Productivity - Screw conveyors - Speed
Uncontrolled terms:Continuity equations - Contrastive analysis - Conveying mechanisms - Experimental platform - High power consumption - Maize straw - Power consumption model - Theoretical modeling
Classification code:605 Small Tools and Hardware - 691.2 Materials Handling Methods - 692.1 Conveyors - 706.1 Electric Power Systems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
Numerical data indexing:Mass_Flow_Rate 1.67e-01kg/s to 1.17e+00kg/s, Mass_Flow_Rate 5.00e-01kg/s, Percentage 1.10e+01%, Percentage 1.17e+01%, Percentage 1.40e+01%, Percentage 5.10e+00%, Percentage 5.20e+00%, Percentage 5.29e+01%, Percentage 5.40e+00%, Percentage 5.80e+00%, Percentage 5.90e+00%, Percentage 6.90e+00%, Percentage 8.60e+00%, Rotational_Speed 5.80e+01RPM to 1.48e+02RPM, Rotational_Speed 5.80e+01RPM, Size 1.60e-01m to 3.00e-01m, Size 1.80e-01m, Size 2.00e-03m to 8.00e-03m, Size 2.50e+00m, Size 2.50e-01m, Size 3.00e-01m, Size 5.00e-03m to 8.00e-03m, Size 6.00e-02m
DOI:10.11975/j.issn.1002-6819.2016.22.003
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 17>
Accession number:20164903093282
Title:Detection method of navigation route of corn harvester based on image processing
Authors:Liangxi, Huizi (1, 2); Chen, Bingqi (1); Jiang, Qiuhui (1); Zhu, Deli (1); Yang, Ming (1); Qiao, Yan (1)
Author affiliation:(1) College of Engineering, China Agricultural University, Beijing; 100083, China; (2) College of Mechanical and Electric Engineering, Shihezi University, Shihezi; 832003, China
Corresponding author:Chen, Bingqi(fbcbq@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:43-49
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In a corn field with an unstructured environment, for the images collection by monocular vision, conventional path recognition algorithms are difficult to guarantee their robustness due to illumination variation, background reflection, shadow noise, and so on. In addition, the increase of the calculation amount of the algorithms caused by the complicated background information of the corn field environment affects the quickness and the real-timeliness of the corn harvester autonomous navigation, which leads to the difficulty of meeting the requirement for the operation efficiency of the corn field harvester and impedes the practical application of the mobile robot technology in agricultural production. The significant premise of visual navigation for a corn harvester is the precise and rapid detection of the navigation route. Unfortunately, some interferences will affect the extraction of the navigation route and the judgment for the edge of the corn field due to the corn shadow and weeds. The vision navigation has many technical advantages of adapting to the complicated field operating environment, has wide detection range, and has rich and complete information. This paper put forward the detection algorithms of the operation routes of the corn harvester and the judgment of the end of the corn field by analyzing the different color features of the visual navigation image. Here we studied the region of interest where lies the target straight line. To improve the rapidity of the navigation path recognition and meet the real-time requirements of autonomous navigation operations, for the color characteristic of the corn field environment, the clustering segmentation of the image was performed based on the analysis of red (R), green (G) and blue (B) components to achieve the respective clusters of the path and the corn field information. We used these color components to extract the target features of the inner and outside of the corn field respectively, and smooth the image using the moving average method with the set length. First, to remove the shadow interference of the corn columns, we compared the G component and the B component of a color image and smoothed the image using the moving average method. For the first frame, we used the distribution of the G component to find the alternate point; for other frames, we connected them with the previous frame to calculate the skew angles of the target line. Then, we extracted the navigation routes based on the Hough transform passing a known point. At last, it would be determined whether the corn harvester reached the end automatically according to the continuous mutation of the R component. The test proved that the processing time of detecting line was 50.1 ms per frame and the detection of the end was accurate and reliable, which could meet the demand of the real operation of a corn harvester in the field. It can be concluded that the navigation routes are extracted and the edge of the corn field is judged accurately, which satisfy the requirement of the practical application of the corn harvester in the field. In addition, the work can also provide the reference for the vision navigation routes' detection of sorghum and some high pole crops with mechanized harvesting. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Image processing
Controlled terms:Agricultural machinery - Agriculture - Color - Crops - Feature extraction - Harvesters - Hough transforms - Image analysis - Image segmentation - Mobile robots - Navigation - Robots - Signal detection
Uncontrolled terms:Agricultural productions - Background information - Clustering segmentation - Illumination variation - Known point Hough transforms - Operation efficiencies - Unstructured environments - Vision navigation
Classification code:716.1 Information Theory and Signal Processing - 731.5 Robotics - 741.1 Light/Optics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921.3 Mathematical Transformations
Numerical data indexing:Time 5.01e+01m/s
DOI:10.11975/j.issn.1002-6819.2016.22.006
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 18>
Accession number:20164903093306
Title:Construction and countermeasures of standard system for agricultural circular economy in China
Authors:Song, Chengjun (1); Zhao, Xuelan (2); Tian, Yishui (1); Qi, Yue (1); Luo, Juan (1); Zhao, Lixin (1); Liu, Tianchi (3)
Author affiliation:(1) Key Laboratory of Energy Resource Utilization from Agricultural Residues MOA), Institute of Energy and Environmental Protection, Chinese Academy of Agriculture Engineering, Beijing; 100125, China; (2) Tianjin Vocaltional College of Bioengineering, Tianjin; 300074, China; (3) Tianshui National Agricultural Science and Technology Park, Tianshui; 741030, China
Corresponding author:Tian, Yishui(yishuit@yahoo.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:222-226
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Agricultural circular economy is the harmonious development mode of population, resources, environment and the development of modern agricultural growth. Agricultural circular economy is not only an important method to the transformation of the mode of agricultural development in China, but also the important content of the development of green sustainable agriculture to follow China's 13th five-year national development planning proposal. The construction of the standard system of agricultural circular economy is the basis and leading work for the development of circular economy, and the establishment of the standard system is also the key technology and management basis for the development of agricultural circular economy. This paper puts forward the concept of agricultural circular economy in China, and then the research status of the present situation and the main problems of agricultural circular economy both at home and abroad are summarized. It is found that the developed countries have accumulated many successful experiences in the field of agricultural circular economy, but the standard system of agricultural circular economy has not been established. Furthermore, this paper summarizes the research progress and practice in the construction of the standard system of agricultural circular economy in China. This paper focuses on the key links of modern agriculture in the irrigation water, pesticide, fertilizer, energy, land, farming, labor, materials, and comprehensive utilization of wastes, and the agricultural system is divided into 5 stages: Design and development, resource conservation, production and processing, circulation and consumption, recycling and disposal. The systematic and comprehensive characteristics of agricultural circular economy are fully considered, and the construction method, basic structures, three-dimensional structure including industry chain, domain chain and hierarchy chain, construction principles and structure diagram of the standard system of agricultural circular economy are clarified based on the agricultural industry chain and the life cycle of agricultural products. Standard system for agricultural circular economy in China are advanced, and the standard system are divided into basic standards, general management standards, integrating industrial chain standards, methods and specification standards. Finally, the relationship of standard system for agricultural circular economy in China, ecological agriculture and organic agriculture is analyzed, and some relevant standards are put forward for prior setting in accordance with the principle of priority combined with the actual needs of the agricultural circular economy in China. At present, the urgent need to develop the individual criteria mainly includes: agricultural circular economy notation and terminology, classification and code; agricultural circular economy guide for standardization; agricultural solid waste comprehensive utilization technology assessment guidelines; material flow analysis method, ecological efficiency and standard calculation method; agricultural circular economy standardization work guidelines. The formulation of standard system for agricultural circular economy in China ensures the compilation order of the single standard, reduces the standards that are repeating and contradictive, and increases the cohesion and the reasonable matching and composition between the single standard. The standardization and regularization of agricultural circular economy in China are conducive to the improvement of management standardization level of agricultural circular economy, and promote the standardization development of agricultural circular economy in China. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:15
Main heading:Industrial economics
Controlled terms:Agricultural products - Agriculture - Chains - Conservation - Ecology - Irrigation - Life cycle - Natural resources - Population statistics - Standardization - Standards - Waste disposal - Waste utilization - Water recycling
Uncontrolled terms:Agricultural industries - Circular economy - Comprehensive utilization technologies - Comprehensive utilizations - Eco-efficient - Economy - Formulation of standards - Three-dimensional structure
Classification code:452.4 Industrial Wastes Treatment and Disposal - 454.3 Ecology and Ecosystems - 602.1 Mechanical Drives - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 902.2 Codes and Standards - 911.2 Industrial Economics
DOI:10.11975/j.issn.1002-6819.2016.22.030
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 19>
Accession number:20164903093281
Title:Calibration method of contact characteristic parameters for corn seeds based on EDEM
Authors:Wang, Yunxia (1); Liang, Zhijie (1); Zhang, Dongxing (1); Cui, Tao (1); Shi, Song (1); Li, Kehong (1); Yang, Li (1)
Author affiliation:(1) College of Engineering, China Agricultural University, Beijing; 100083, China
Corresponding author:Yang, Li(yl_hb86@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:36-42
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The pneumatic metering device has the advantages of high qualified index, less mechanical damage to seeds and good adaptability for high-speed operation. But traditional calculation method is not capable of analyzing the law of seeds motion because of the complex stress state. Discrete element method (DEM) is the key method to solve the above problem. However, physical characteristics parameters of particles, mainly consisting of static friction coefficient and rolling friction coefficient between corn seeds, are key factors for reliable simulation results in the DEM. Due to the difference between corn seeds and simulation particles in surface shape and size, the actual physical parameters of corn seeds are not suitable for the EDEM (enhanced discrete element method). Particles models established in the EDEM are rougher than corn seeds, which leads to the distortion of simulation results. Therefore calibration works for particle parameters are essential. In this paper, a new method was proposed for actively seeking the target parameters based on regression analysis. It was estimated that repose angle was commonly influenced by static friction coefficient and rolling friction coefficient between corn seeds. All factors simulation experiments were conducted to obtain the regression equations, of which the tangent value of repose angle at different contact material was separately taken as the dependent variables, and the static friction coefficient and rolling friction coefficient between corn seeds were taken as independent variables. In order to decrease the measuring error, MATLAB software was used for images acquisition and analysis. The variance analysis showed that the static friction coefficient and rolling friction coefficient between corn seeds had significant influence on the repose angle and natural heaping angle separately at significance level of 5%. The tangent value of repose angle had an increase trend with the increase of static friction coefficient and rolling friction coefficient between corn seeds. For the first test with organic plate, it had a bigger increase when the static friction coefficient was at 0-0.2 and then increased slowly, at this time which was mainly influenced by the rolling friction coefficient. For the second test with aluminum plate, it also increased with the increase of static friction coefficient and rolling friction coefficient between corn seeds in a consistent state. By the simulation tests, 2 regression equations were obtained. For solving the independent variables, the actual tangent values of repose angle with different contact material were measured by the actual tests and taken as the dependent variables. By this way, the static friction coefficient of 0.0338 and the rolling friction coefficient of 0.0021 between corn seeds were obtained. Verification tests with calibrated physical parameters were carried out. Results showed that the tangent values of repose angle were consistent with the actual tests. The simulation model of corn seeds was composed of multiple small spherical particles. There were sunk areas between adjacent seeds, so the contact area between corn seeds increased and meanwhile the friction force was increased. Corresponding relation between actual seeds and simulation model was found by this calibration method. The boundary of repose angle was extracted to compare the simulation and actual test results, which verified that the calibrated physical parameters were applicable for the EDEM and the method was feasible. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Friction
Controlled terms:Calibration - Electric contacts - Finite difference method - MATLAB - Models - Regression analysis - Stiction - Testing - Tribology
Uncontrolled terms:Complex stress state - Contact characteristics - Corn - Corresponding relations - High-speed operation - Independent variables - Physical characteristics - Static friction coefficient
Classification code:704.1 Electric Components - 921 Mathematics - 921.6 Numerical Methods - 922.2 Mathematical Statistics - 931 Classical Physics; Quantum Theory; Relativity
Numerical data indexing:Percentage 5.00e+00%
DOI:10.11975/j.issn.1002-6819.2016.22.005
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 20>
Accession number:20164903093304
Title:Analysis on heat storage layer and thickness of soil wall in solar greenhouse based on theory of temperature-wave transfer
Authors:Bai, Qing (1, 2); Zhang, Yahong (1); Sun, Lixin (1)
Author affiliation:(1) School of Agriculture, Ningxia University, Yinchuan; 750021, China; (2) Ningxia Technology Development Strategy and Information Study Institution, Yinchuan; 750001, China
Corresponding author:Zhang, Yahong(zhyhcau@sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:207-213
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The wall plays an important role in the study of the greenhouse. Heat storage layer and thickness of the wall are 2 key factors for studying wall thermal environment and optimizing the structure. As widely used wall in solar greenhouse, soil wall is typical and representative, and it is significant to study heat storage layer and thickness of soil wall. To study the varying rule of the heat storage layer and to find the optimum thickness of the wall, an experiment was performed in Yanghe County, Yinchuan, Ningxia, China in 2011. The fifth generation greenhouse with soil wall from Shouguang City, Shandong Province was used. The CR10X-2M and CR3000 data collectors from America were adopted, and 18 T-types thermocouple temperature probes were also used to test inner wall temperature at the positions of 0, 10, 20, 30, 40, 50, 60, 80, 100, 150, 200, 230, 250, 280 and 330 cm thickness (along horizontal direction of wall body). The temperature variation was analyzed in the horizontal direction. Indoor temperature and wall temperature were used to determine the thickness of heat storage layer. Besides, a method for calculating wall thickness was pointed out, which was based on wall temperature spreading speed. The results showed with the increase of wall depth, the variation of bilateral temperature-wave of the wall became less obvious. However, the temperatures were gradually decreased from wall surface to exterior surface. Temperature-wave amplitude approached zero at 50-230 cm depth of the wall surface, which was in a stable state. The thickness of heat storage layer was got by using the lowest temperature of inner greenhouse and inner wall. The temperature changed obviously in 0-50 cm and 280-330 cm depth of the wall, which showed wave layer, stable layer and insulation layer existing in the north wall of solar greenhouse, and the thickness of heat storage layer was various. In January, the amplitude of temperature within a month at wave layer ranged from 10.01 to 0.34℃ with an average temperature amplitude of 3.30℃, and the average temperature was 11.70℃. The amplitude of temperature within a month at stable layer ranged from 0.17 to 0.10℃ with an average temperature amplitude of 0.08℃, and the average temperature was 4.76℃. The amplitude of temperature within a month at insulating layer ranged from 0.29 to 5.18℃ with an average value of 2.73℃, and the average temperature was -9.16℃. The thickness of the heat storage layer in experimental greenhouses was 55-200 cm and the average thickness was 109.2 cm. With the rising of the temperature outside, the thickness of heat storage layer was gradually decreased. The average thickness of heat storage layer was 144 cm in January while it was 100.9 cm in March. The thickest was 200 cm in January, while the thinnest was 55 cm in March. The most suitable thickness of the soil wall was 1.5 m in Yinchuan area, which was calculated by using the temperature wave propagation velocity. In practical production, the soil wall should be 250 cm thick at the bottom, 100 cm thick at the top and 150 cm thick at the middle. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Digital storage
Controlled terms:Greenhouses - Heat storage - Soils - Solar heating - Thermocouples - Wave propagation
Uncontrolled terms:Practical production - Soil wall - Storage layers - Temperature amplitude - Temperature variation - Thermal environment - Thickness of walls - Walls
Classification code:483.1 Soils and Soil Mechanics - 657.1 Solar Energy and Phenomena - 722.1 Data Storage, Equipment and Techniques - 821.6 Farm Buildings and Other Structures - 944.5 Temperature Measuring Instruments
Numerical data indexing:Size 0.00e+00m to 5.00e-01m, Size 1.00e+00m, Size 1.01e+00m, Size 1.09e+00m, Size 1.44e+00m, Size 1.50e+00m, Size 2.00e+00m, Size 2.50e+00m, Size 2.80e+00m to 3.30e+00m, Size 3.30e+00m, Size 5.00e-01m to 2.30e+00m, Size 5.50e-01m to 2.00e+00m, Size 5.50e-01m
DOI:10.11975/j.issn.1002-6819.2016.22.028
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 21>
Accession number:20164903093278
Title:Design and performance analysis of drive system for high clearance self-propelled corn detasseling machine
Authors:Chen, Suiying (1); Du, Yuefeng (1); Xie, Bin (1); Song, Zhenghe (1); Mao, Enrong (1); Chen, Yu (1)
Author affiliation:(1) Beijing Key Laboratory of Optimized Design for Modern Agricultural Equipment, College of Engineering, China Agricultural University, Beijing; 100083, China
Corresponding author:Mao, Enrong(gxy15@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:10-17
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:A hydrostatic drive system scheme for the high clearance self-propelled corn detasseling machine was proposed and the dynamic performance of the system was simulated and tested in this paper. Although detasseling machines have much higher working efficiency than manual detasseling, they have just been used for a few years in China and mostly were imported from abroad at a high price. Since the machine demanded a high ground clearance, the closed volumetric speed control loop with one pump and four motors was adopted. The engine directly drives the pump to output high pressure fluid to the four-wheel motors, and then the motors drive the hub reducers to turn the wheels. It can be concluded that the vehicle can achieve 3 gears of I, II and III by choosing the appropriate maximum and minimum displacements of motors and reducer gear ratios. To better analyze the performance of the drive system, a detasseling machine model with 15 degrees of freedom was built according to the vehicle structure features. The vehicle model included vehicle body model, wheel model and four-wheel independent suspension system model. Meanwhile, the mathematical model of the hydrostatic drive system was derived, which included pump model, motor model and reducer model. Then, the simulation model of vehicle dynamics of detasseling machine was presented using the software Matlab/Simulink based on the mathematical models. The simulation model was used to study the performance of speed and system pressure of the vehicle at 3 gears. And the results showed that the vehicle could get a maximum travel speed of 15.8, 19.7 and 26.1 km/h, and a steady system pressure of about 6.29, 7.30 and 8.94 MPa at the 3 gears of I, II and III, respectively, which could meet various application conditions. As a special component of detasseling machine, the effect of the suspension system on the drive system was testified. By exerting a road excitation on one wheel, the system pressure of the vehicle with the suspension was contrasted with the one without suspension. The results showed that the pressure of the one with the suspension fluctuated much narrower and smoother than the other, which meant the suspension could effectively improve the performance of the drive system. To verify the mathematical model and to further research the drive system, a high clearance self-propelled corn detasseling machine was designed to conduct the tests. During the process of changing the displacement of pump from the minimum to the maximum value at each gear, the maximum travel speed was recorded, and the variations of the inlet and outlet pressure of the pump and motor were measured. The main test devices contained oil pressure sensors, acceleration sensors, data acquisition card of National Instruments, switching power supply and laptop, and the software LabVIEW was used for data processing. The vehicle tests showed that with the increase of pump displacement, the system pressure of the high pressure side first trended to increase sharply and then decreased to a stable value of 6.361, 7.286 and 8.717 MPa at the 3 gears of I, II and III, respectively, which was consistent with the simulation results. And the pressure of the low pressure side was about 2.4 MPa, which was equal to the system charge pressure. In addition, the maximum driving speed of the machine at the 3 gears was 15, 19 and 24 km/h respectively, which was lower than the theoretical values. That was mainly due to the leakage loss of hydraulic components and the mechanical friction loss. The simulation and test results showed that the vehicle drive system had a rapid response and a good performance, and the correctness of the mathematical model of the machine was also verified. The study can provide a technical reference for the independent research and development of the high clearance self-propelled corn detasseling machine in China. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Suspensions (components)
Controlled terms:Agricultural machinery - Automobile suspensions - Computer programming languages - Computer simulation - Computer software - Data acquisition - Data handling - Degrees of freedom (mechanics) - Digital storage - Dynamic models - Electric power supplies to apparatus - Gears - Hydraulic machinery - Hydraulics - Magnetic levitation vehicles - MATLAB - Models - Pumps - Software testing - Speed - Testing - Vehicle performance - Vehicle wheels - Vehicles - Wheels
Uncontrolled terms:Acceleration sensors - Data acquisition cards - Drive systems - Hydrostatic drive systems - Independent research - Independent suspension system - Performance analysis - Switching power supplies
Classification code:601.2 Machine Components - 618.2 Pumps - 632.1 Hydraulics - 632.2 Hydraulic Equipment and Machinery - 662.1 Automobiles - 662.4 Automobile and Smaller Vehicle Components - 722.1 Data Storage, Equipment and Techniques - 723 Computer Software, Data Handling and Applications - 821.1 Agricultural Machinery and Equipment - 921 Mathematics - 931.1 Mechanics
Numerical data indexing:Pressure 2.40e+06Pa, Pressure 8.72e+06Pa, Pressure 8.94e+06Pa, Velocity 6.67e+00m/s, Velocity 7.25e+00m/s
DOI:10.11975/j.issn.1002-6819.2016.22.002
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 22>
Accession number:20164903093289
Title:Analysis of oxidation characteristics on combustion of diesel fuels with CeO<inf>2</inf>nano-catalyst particulates
Authors:Meng, Jian (1, 2); Liu, Junheng (1); Sun, Ping (1); Feng, Haojie (1)
Author affiliation:(1) School of Automobile and Traffic Engineering, Jiangsu University, Zhenjiang; 212013, China; (2) School of Transportation and Vehicle Engineering, Shandong University of Technology, Zibo; 255049, China
Corresponding author:Liu, Junheng(liujunheng@ujs.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:93-99
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Diesel particle emission is a major resource of particulate matter 2.5 (PM2.5) and is harmful to human health. Diesel particulate filter (DPF) is a principal method to reduce diesel PM emission. The DPF requires periodical regeneration by oxidizing the particulates deposited in filters to prevent plugging. The exhaust gas temperature of the diesel engine is considerably lower than the ignition temperature of diesel particulates. Adding a nano-catalyst directly to the fuel to lower the ignition temperature of the diesel particulates is a good method. CeO<inf>2</inf>nano-catalyst is proved to oxide the soot with high catalytic activity and stability, and is considered as a promising catalyst for application in DPF. The influence of CeO<inf>2</inf>nano-catalyst added in diesel oil on the oxidation and structure characteristics of diesel particulates was studied using thermogravimetric analysis (TGA) and scanning electron microscope (SEM) in this article. Three kinds of CeO<inf>2</inf>nano-catalyst fuels were confected, in which CeO<inf>2</inf>mass fractions were 0, 50 and 100 mg/kg (F0, F50 and F100), respectively. The micro-orifice uniform deposition impactor (MOUDI) was used to collect the particulates generated by burning P0, P50 and P100. The SEM was used to study the influence of CeO<inf>2</inf>mass fraction on the particle morphology characteristics. The effects of heating rates and CeO<inf>2</inf>mass fraction on particle thermal oxidation characteristics were studied by thermogravimetric analysis method. The activation energy of particulates was calculated with Coast-Redfern integrate method. The results show that there were obvious clusters morphology of particulates from diesel engine fueled with the three CeO<inf>2</inf>nano-catalyst fuels, and the particle distribution sizes were mainly concentrated between 20 nm and 70 nm, which were single peak curves. With the increase of CeO<inf>2</inf>mass fraction, the particle sizes of P0, P50 and P100, the mean diameter of particulates decreased and the box dimension increased, accordingly. The mean particle size of P50 and P100 decreased by 13% and 20% compared with P0, respectively. For the three particulates, the thermogravimetric (TG) curves and differential thermogravimetric (DTG) curves moved to high temperature region, the temperatures of initial oxidation, peak weight-loss rate and termination reaction increased, and the oxidation reaction areas widened, the thermal weight-loss rate peaks decreased as the heating rate increased. The heating rate scarcely influenced the activation energy for the same particulates. With the same heating rate, the activation energy,the initial oxidation temperature, the peak weight-loss rate temperature and the termination reaction temperature of particulates decreased with the increase of CeO<inf>2</inf>mass fraction. Compared with P0, the initial oxidation temperature decreased by 4.2%, 8.5%, peak weight-loss rate temperature decreased by 5%, 6.3%, and the termination reaction temperatures decreased by 4.9%, 6.1% for P50 and P100, respectively. It is found that CeO<inf>2</inf>nano-catalysts could reduce the activation energy of particulates oxidation, lower the initial oxidation temperature, decrease the particulates diameter, and promote the oxidation of particulates. This article can provide a theoretical reference for the CeO<inf>2</inf>nano-catalyst added to diesel oil to reduce the ignition temperature of diesel particulates in DPF. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Thermogravimetric analysis
Controlled terms:Activation analysis - Activation energy - Catalysis - Catalyst activity - Catalysts - Chemical activation - Diesel engines - Diesel fuels - Engines - Fuels - Heating - Heating rate - Morphology - Oxidation - Particle size - Particles (particulate matter) - Particulate emissions - Scanning electron microscopy - Thermooxidation
Uncontrolled terms:Diesel particle emissions - Diesel particulate filters - Differential thermogravimetric - Exhaust gas temperatures - Nanoparticulates - Oxidation characteristics - Particle distributions - Structure characteristic
Classification code:451.1 Air Pollution Sources - 523 Liquid Fuels - 612.2 Diesel Engines - 641.2 Heat Transfer - 801 Chemistry - 802.2 Chemical Reactions - 803 Chemical Agents and Basic Industrial Chemicals - 804 Chemical Products Generally - 951 Materials Science
Numerical data indexing:Percentage 1.30e+01%, Percentage 2.00e+01%, Percentage 4.20e+00%, Percentage 4.90e+00%, Percentage 5.00e+00%, Percentage 6.10e+00%, Percentage 6.30e+00%, Percentage 8.50e+00%, Size 2.00e-08m to 7.00e-08m
DOI:10.11975/j.issn.1002-6819.2016.22.013
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 23>
Accession number:20164903093291
Title:Analysis and test on circuit characteristic of multi-stage constant power governing system using double-stator pump
Authors:Wen, Desheng (1); Chai, Weichao (1); Wang, Jing (1); Chen, Fan (1); Zhen, Xinshuai (1); Ma, Guanglei (1)
Author affiliation:(1) College of Mechanical Engineering, Yanshan University, Qinhuangdao; 066004, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:107-112
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Traditional pump-motor constant power governing system can achieve power matching between the load and the prime mover to reduce energy waste under the conditions with the constant power load. In practical application, some conditions demand hydraulic system outputting constant torque but different speeds. For example, agricultural machinery walking in the same road conditions requires different speeds to choose. However, limited by the governing principle (the product of rotational speed and torque will be a fixed value), traditional pump-motor constant power governing system can't meet the above conditions. So it can only use throttle governor, which will inevitably lead to energy waste and efficiency decrease. Therefore, it's necessary to research a new hydraulic system which can meet multi-stage constant power conditions in principle. New double-stator pump (motor) offers the possibility of studying multi-stage constant power governing system. Because internal and external multiple pumps exist in one housing implements and share one rotor, double-stator pump can output a variety of different flows by controlling the working modes of the respective pumps. It is used to replace the old pump in the traditional pump-motor constant power governing system which then becomes a new multi-stage constant power governing system. A comparative analysis of the circuit characteristics was carried out between the multi-stage constant power governing system and the traditional system. Then a test platform was set up to carry out the experiment. The results indicated that the three-stage constant power governing system composed of single-acting double-stator pump could meet constant power condition, which was just as the traditional system. Under the same condition of constant power load, the common quantitative pump hydraulic system's transmission efficiency was only 82%-86%, but both the traditional pump-motor constant power governing system and the three-stage constant power governing system could reach 94%, at least increased by more than 7% compared with the former. Besides, by changing the working mode of double-stator pump, the multi-stage constant power governing system output multi-stage speeds and constant torque. So it could meet multi-stage constant power conditions without throttle governor, which meant more energy was saved. For instance, the multi-stage constant power governing system and the traditional pump-motor constant power governing system both adapted to the condition which needed the power of about 17.5 kW. When the output torque of motor is constant 195 N·m, if the condition's speed requirement dropped from 860 to 540 r/min, the three-stage constant power governing system chose outer pump of double-stator pump working alone to meet the needs of condition. At this time the required power for it was 10.95 kW, which would save 6.67 kW compared to the traditional pump-motor constant power governing system which only used throttle governor to meet the needs of condition. If the condition's speed requirement further dropped to 350 r/min, the three-stage constant power governing system chose inner pump of double-stator pump working alone to meet the needs of condition. And it required 10.95 kW on power, which would save 10.63 kW compared to the traditional pump-motor constant power governing system. The analysis and test not only enrich the application of double-stator pump for the future, but also provide the important reference for the application of constant power governing system in agricultural machinery, engineering machinery, aerospace machinery and other fields to improve their working efficiency. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:21
Main heading:Pumps
Controlled terms:Agricultural machinery - Agriculture - Experiments - Governors - Hydraulic equipment - Hydraulic machinery - Speed - Stators - Timing circuits - Torque
Uncontrolled terms:Comparative analysis - Constant power - Double stator - Engineering machinery - Multi stage - Pump hydraulic system - Traditional systems - Transmission efficiency
Classification code:602.1 Mechanical Drives - 618.2 Pumps - 632.2 Hydraulic Equipment and Machinery - 705.1 Electric Machinery, General - 713.4 Pulse Circuits - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.1 Agricultural Machinery and Equipment - 901.3 Engineering Research - 931.2 Physical Properties of Gases, Liquids and Solids
Numerical data indexing:Percentage 7.00e+00%, Percentage 8.20e+01% to 8.60e+01%, Percentage 9.40e+01%, Power 1.06e+04W, Power 1.10e+04W, Power 1.75e+04W, Power 6.67e+03W, Rotational_Speed 3.50e+02RPM, Rotational_Speed 8.60e+02RPM to 5.40e+02RPM, Torque 1.95e+02N*m
DOI:10.11975/j.issn.1002-6819.2016.22.015
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 24>
Accession number:20164903093302
Title:Performance evaluation of GIMMS NDVI3g and GIMMS NDVIg based on MODIS and Landsat in Tibetan Plateau
Authors:Du, Jiaqiang (1, 2); Wang, Yuehui (3); Shi, Huading (1, 2); Fang, Shifeng (4); He, Ping (1, 2); Liu, Weiling (1, 2); Yin, Junqi (5)
Author affiliation:(1) Chinese Research Academy of Environmental Sciences, Beijing; 100012, China; (2) State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing; 100012, China; (3) The Border Defence Academy, Chinese People's Liberation Army, Xi'an; 710108, China; (4) The State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing; 100101, China; (5) Xinjiang Academy of Environmental Protection Science, Xinjiang; 830011, China
Corresponding author:Yin, Junqi(673384991@qq.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:192-199
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:GIMMS NDVI dataset must be re-calculated every time when New year's data are added, due to the GIMMS NDVI data set is dynamic in nature, and this leads to differences between GIMMS NDVI3g and GIMMS NDVIg throughout their overlapping period (1981-2006). How to understand and treat these discrepancies is premise and basis for comprehensive utilizing the datasets of GIMMS NDVIg and GIMMS NDVI3g to scientifically detect vegetation's historic variations, forecast its future tendency and guide the ecological protection and construction. With MODIS NDVI datasets from 2000 to 2012 and 495 Landsat samples of 20 km × 20 km from 2000 to 2006, performances of GIMMS NDVIg and GIMMS NDVI3g were evaluated during the period from 2000 to 2006, and long-term variation of vegetation monitoring used both GIMMS datasets during 1982-2006 were compared and analyzed in this paper. Firstly, absolute values of GIMMS NDVIg, GIMMS NDVI3g and MODIS NDVI with Landsat NDVI were compared. Then, the differences between a Landsat sample-pair (i.e., two 20 × 20 km<sup>2</sup>Landsat samples acquired for the same location at different years) and GIMMS NDVIg, GIMMS NDVI3g and MODIS NDVI datasets at the same time points were evaluated. Besides, GIMMS NDVIg and GIMMS NDVI3g with MODIS NDVI during 2000-2006 in term of temporal trends by applying a simple linear regression model based monthly anomalies and the seasonal Mann-Kendall trend test were compared at region, and correlations were conducted at pixel scales. Finally, trends of GIMMS NDVIg with that of GIMMS NDVI3g in three seasons (spring, summer and autumn) and growing season during 1982-2006 were compared at region and pixel scales. The results showed that almost equal capability of capturing variations of seasonal and monthly phenology for both GIMMS datasets was found. The NDVI value of GIMMS NDVI3g was generally larger than that of GIMMS NDVIg, or even larger than NDVI of MODIS NDVI. Compared with GIMMS NDVI3g, patterns and trends of GIMMS NDVIg were more similar to that of MODIS NDVI and Landsat. Although spatial patterns of GIMMS NDVI3g change in growing season during 1982-2006 resembled that of GIMMS NDVIg, wider range characterized significant increase in spring NDVI were detected with GIMMS NDVIg, and the discrepancies between both GIMMS NDVI datasets mainly concentrated in the hinterland of the Tibetan Plateau. The increase trend of vegetation growth in spring using GIMMS NDVIg was more severe than that using GIMMS NDVI3g, but the opposite situation was found in summer. The remarkable difference of NDVI variation in spring may lead to differences in the analysis of the phenology using both GIMMS NDVI datasets of the Qinghai Tibet Plateau. Long-term NDVI datasets are the basic data for many ecological models, the differences among these datasets may influence the accuracy of model results. Before conducting the relevant research using NDVI datasets, the applicability of NDVI datasets is needed to evaluate, and it is the premise to obtain more consistent with the actual situation objective results. Combined with other ecological datasets, such as vegetation coverage fraction, leaf area and vegetation production of historical field data is important to identify the similarities and differences between the two GIMMS NDVI datasets and establish a connection between them for reasonably monitoring vegetation dynamics. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:36
Main heading:Radiometers
Controlled terms:Biology - Ecology - Forestry - Linear regression - Pixels - Regression analysis - Remote sensing - Vegetation
Uncontrolled terms:Ecological protection - GIMMS NDVI3g - GIMMS NDVIg - Mann-Kendall trends - Qinghai Tibet plateau - Simple linear regression - Vegetation dynamics - Vegetation monitoring
Classification code:454.3 Ecology and Ecosystems - 461.9 Biology - 922.2 Mathematical Statistics - 944.7 Radiation Measuring Instruments
Numerical data indexing:Area 2.00e+07m2, Size 2.00e+04m
DOI:10.11975/j.issn.1002-6819.2016.22.026
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 25>
Accession number:20164903093285
Title:Design and test on pneumatic type automatic tray feeder of seeder for tray nursing seedings of rice
Authors:Ma, Xu (1); Tan, Yongxin (1); Qi, Long (1); Huang, Guan (1); Lu, Fangyuan (1); Chen, Lintao (1)
Author affiliation:(1) College of Engineering, South China Agricultural University, Guangzhou; 510642, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:63-69
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Factory seedling nursery is one of the most important parts in the process of rice production mechanization. At present most of the work feeding the trays into the rice seedling nursery planter is finished one by one manually, which is labor-intensive and inefficient. In order to reduce labor intensity and improve the production efficiency of rice seedling nursery pipeline, a pneumatic type automatic tray feeder, which could supply the seedling trays rapidly and automatically, was developed after studying the characteristics of frequently-used tray. The device consisted of conveying mechanism, tray dropping mechanism and control system. The conveying mechanism, which included the former conveying section and the latter conveying section, was designed to convey the trays that were stacked before use (which could be up to 10 trays per stack). By establishing the mathematical model of convey mechanism and analyzing the conveying deceleration process of trays, the conveying speed relationship between the pneumatic type automatic tray feeder and the rice seedling nursery pipeline was obtained, so that the speed of the automatic tray feeder could be confirmed and meet the requirements of tray conveying under the different productivities. The tray dropping mechanism was designed to feed the trays automatically. By the cylinder driving, the trays except the bottom tray could be rapidly lifted through the lifting finger rotation on either side of the trays. After the bottom tray was conveyed away, the lifting finger rotated in the opposite direction and the trays would be dropped, and then that cycle was repeated. The control system was designed so that the conveying mechanism could be controlled to convey trays orderly and the tray dropping mechanism could be controlled to feed trays accurately. Through the proximity switches detecting of the control system, the stacking trays would be conveyed into the latter conveying section and the trays would be lifted or dropped by the tray dropping mechanism. Therefore, the trays could be automatically supplied one by one rapidly. In order to test the performance of the pneumatic type automatic tray feeder, the orthogonal experiment was carried out, in which the feeding success rate was regarded as the index and the productivity, the feeding time of tray dropping mechanism and the stacking trays deviation were regarded as the influence factors. Experiment results showed that the sequence of influence factors in affecting the feeding success rate from high to low was the stacking trays deviation, the feeding time and the productivity. The stacking trays deviation had significant influence on the feeding success rate while the feeding time had certain influence on it. The feeding success rate decreased with the rising of the stacking trays deviation and the feeding success rate increased with the rising of the feeding time. The productivity had little effect on the feeding success rate. When the stacking trays deviation was 0-6 mm and the feeding time was 0.8 s, the feeding success rate was 98.67%-100% with a productivity of 600-1000 trays per hour. The pneumatic type automatic tray feeder can effectively enhance the productivity of rice nursing seedlings pipeline and reduce the labor intensity. The experimental indices meet the using requirements of rice precision seedling. This study has a great significance in improving the automation level of rice nursing seedlings pipeline. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:18
Main heading:Feeding
Controlled terms:Agricultural machinery - Control systems - Design - Machine design - Models - Nursing - Pipelines - Pneumatics - Productivity - Societies and institutions - Testing
Uncontrolled terms:Automation levels - Conveying mechanisms - Cylinder driving - Deceleration process - Orthogonal experiment - Production efficiency - Rice seedling nurseries - Seeder
Classification code:461.7 Health Care - 601 Mechanical Design - 619.1 Pipe, Piping and Pipelines - 632.3 Pneumatics - 691.2 Materials Handling Methods - 731.1 Control Systems - 821.1 Agricultural Machinery and Equipment - 901.1.1 Societies and Institutions
Numerical data indexing:Percentage 9.87e+01% to 1.00e+02%, Size 0.00e+00m to 6.00e-03m, Time 8.00e-01s
DOI:10.11975/j.issn.1002-6819.2016.22.009
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 26>
Accession number:20164903093293
Title:Atomization characteristics of normal flat fan nozzle and air induction nozzle under high speed airflow conditions
Authors:Tang, Qing (1, 2); Chen, Liping (1, 2); Zhang, Ruirui (1, 2); Zhang, Bin (1, 3); Yi, Tongchuan (1, 2); Xu, Min (1, 2); Xu, Gang (1, 2)
Author affiliation:(1) Beijing Research Center for Intelligent Agricultural Equipment, Beijing; 100097, China; (2) Beijing Research Center for Information Technology in Agriculture, Beijing; 100097, China; (3) School of Astronautics, Northwestern Polytechnical University, Xi'an; 710068, China
Corresponding author:Chen, Liping(chenlp@nercita.org.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:121-128
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Flat fan nozzles and air induction nozzles are often used in ground spraying. Although the atomization characteristics of these 2 kinds of nozzles in low speed flow were studied sufficiently, their high speed atomization characteristics were still not very clear. The objectives of this research were to assess the atomization characteristics of the LU-120-03 normal flat fan nozzle and the IDK-120-03 air induction nozzle, and their suitability in agricultural aerial spray application. The experiment was conducted in the IEA-I high speed wind tunnel at National Engineering Research Center of Intelligent Equipment for Agriculture (NERCIEA) with Marvern Spraytec laser diffraction system. The measurement point was set at 0.15, 0.25 and 0.35 m away from the orifice of the nozzle which was 0.1 m outside the exit of the tunnel. The wind speed range was from 121.7 to 305.5 km/h, and the tube pressure was set to be 0.3, 0.4 and 0.5 MPa. The nozzle was installed on an electric lifting platform which could be traversed vertically so that the entire spray plume could be sampled by the laser diffraction system. Three replications for each nozzle/pressure tested were taken, and the standard deviation of volume middle diameter of droplets was required to be less than or equal to 5% of the mean. The results of the experiment to the LU-120-03 nozzle showed that when the wind speed increased from 150 to 305 km/h, the volume middle diameter of the droplets decreased from 210 to 130 μm. The relative span of the droplets was found to slightly increase from 1.3 to 1.5 with the increase of the wind speed when the tube pressure exceeded 0.4 MPa. The volume middle diameter of the droplets was also found to be related to the tube pressure. When the wind speed was less than 250 km/h, the increase of the tube pressure could decrease the volume middle diameter of the droplets. However, it would increase the volume middle diameter slightly when the wind speed exceeded 280 km/h. The main reasons of the droplet atomization were also discussed, and the aerodynamic shear stress was believed to be one of the most important reasons. Droplets generated by the IDK-120-03 nozzle had a different behavior. The volume middle diameter of the droplets decreased rapidly (by about 70%) when the wind speed increased from 120 to 305 km/h. Meanwhile, it was not affected by the tube pressure. The relative span of the droplets was mainly affected by the wind speed. When the wind speed was less than 220 km/h, the relative span of the droplets was in proportion to the wind speed. When the wind speed exceeded 220 km/h, the relative span of the droplets decreased slightly with the increase of the wind speed. The increase of the tube pressure could also increase the relative span of the droplets slightly. The measuring distance from the orifice of the nozzle was also found to be important to the diameter and relative span of the droplets. In our results, 0.35 m away from the orifice of the nozzle was a proper measuring point, at which the droplets were fully atomized. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Spray nozzles
Controlled terms:Agriculture - Atomization - Aviation - Diffraction - Drops - Nozzles - Orifices - Shear stress - Speed - Spraying - Tubes (components) - Wind - Wind tunnels
Uncontrolled terms:Atomization characteristics - High-speed wind tunnel - Intelligent equipment - Laser diffractions - Measurement points - Measuring distances - Plant protection - Standard deviation
Classification code:431.1 Air Transportation, General - 443.1 Atmospheric Properties - 619.1 Pipe, Piping and Pipelines - 631.1 Fluid Flow, General - 651.2 Wind Tunnels - 802.3 Chemical Operations - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
Numerical data indexing:Percentage 5.00e+00%, Percentage 7.00e+01%, Pressure 4.00e+05Pa, Pressure 5.00e+05Pa, Size 1.00e-01m, Size 2.10e-04m to 1.30e-04m, Size 3.50e-01m, Velocity 3.33e+01m/s to 8.47e+01m/s, Velocity 3.38e+01m/s to 8.49e+01m/s, Velocity 4.17e+01m/s to 8.47e+01m/s, Velocity 6.11e+01m/s, Velocity 6.95e+01m/s, Velocity 7.78e+01m/s
DOI:10.11975/j.issn.1002-6819.2016.22.017
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 27>
Accession number:20164903093286
Title:Optimal parameters prediction and control of rice threshing for longitudinal axial threshing apparatus
Authors:Tang, Zhong (1); Li, Yaoming (1); Liang, Zhenwei (1)
Author affiliation:(1) School of Agricultural Equipment Engineering, Jiangsu University, Zhenjiang; 212013, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:70-76
Language:English
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Operating parameters such as threshing cylinder speed, concave clearance and bar spacing are the most important factors that influence the power consumption of threshing apparatus and grain loss ratio during the threshing process. In order to obtain rice threshing optimal operating parameters, investigations were conducted on the longitudinal axial threshing apparatus test bench of combine harvester. The threshing power consumption and grain loss ratio of longitudinal axial threshing apparatus were measured at the different combination of cylinder speed, concave clearance and bar spacing. Rice threshing experiment results were analyzed by carrying out regression analysis and the significance of regression effects assessing. The confidence interval of the optimal operating parameters was used to control the performance of threshing and separation process, and the optimal variables of the longitudinal axial threshing apparatus were predicted in advance and tested soon afterwards. When the total grain loss ratio was controlled within less than 0.33% and the threshing power consumption was less than 46.36 kW with a confidence of 0.95, the confidence interval of the best cylinder speed was 772.61-905.74 r/min, the best confidence interval of concave clearance was 22.18-37.93 mm, and the best confidence interval of bar spacing was 104.96-170.17 mm. The results showed that the best threshing cylinder speed was 839 r/min, the best concave clearance was 30 mm and the best bar spacing was 138 mm. These operating parameters can reduce the energy requirements of threshing process and also can lead to low grain loss. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Agriculture
Controlled terms:Agricultural machinery - Crops - Cylinders (shapes) - Electric power utilization - Grain (agricultural product) - Harvesters - Longitudinal control - Optimization - Regression analysis
Uncontrolled terms:Combine harvesters - Confidence interval - Energy requirements - Grain loss - Operating parameters - Prediction and control - Regression effects - Separation process
Classification code:706.1 Electric Power Systems - 731.3 Specific Variables Control - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921.5 Optimization Techniques - 922.2 Mathematical Statistics
Numerical data indexing:Percentage 3.30e-01%, Power 4.64e+04W, Rotational_Speed 7.73e+02RPM to 9.06e+02RPM, Rotational_Speed 8.39e+02RPM, Size 1.05e-01m to 1.70e-01m, Size 1.38e-01m, Size 2.22e-02m to 3.79e-02m, Size 3.00e-02m
DOI:10.11975/j.issn.1002-6819.2016.22.010
Funding Details: Number; Sponsor: (2015M581742; China Postdoctoral Science Foundation
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 28>
Accession number:20164903093296
Title:Estimation of soil moisture in farmland using improved water cloud model and Radarsat-2 data
Authors:Yang, Guijun (1, 2, 3); Yue, Jibo (1, 2, 5); Li, Changchun (5); Feng, Haikuan (1, 2); Yang, Hao (2, 3); Lan, Yubin (3, 4)
Author affiliation:(1) Beijing Research Center for Information Technology in Agriculture, Beijing; 100097, China; (2) National Engineering Research Center for Information Technology in Agriculture, Beijing; 100097, China; (3) Key Laboratory of Agri-informatics, Ministry of Agriculture, Beijing; 100097, China; (4) Beijing Engineering Research Center of Agricultural Internet of Things, Beijing; 100097, China; (5) School of Surveying and Land Information Engineering, Henan Polytechnic University, Jiaozuo; 454000, China
Corresponding author:Yue, Jibo(yuejibo@hotmail.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:146-153
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Soil moisture is one key factor to restrict the growth of crops in rainless regions, and it is crucial to farmland production and can significantly affect the irrigation decision-making for agricultural management. Polarimetric SAR is very sensitive to soil moisture and can penetrate smoke, fog, rain and snow, etc. Therefore, polarimetric SAR system can operate in all-weather conditions. Moreover, soil moisture of farmland can be detected the by penetrating the vegetation and soil to reach the subsurface. In this study, in-situ measurements were carried out in Yangling district, Shannxi province, an important winter wheat producing area in China. Soil moisture and crop parameters (such as leaf area index (LAI), biomass and vegetation water content) were obtained by different teams at Radarsat-2 satellite transit time. Radar vegetation index (RVI), which was less sensitive to change in environmental conditions, had strong correlations with LAI, biomass and vegetation water content, etc. Aiming at monitoring soil moisture by satellite polarimetric SAR data conveniently and accurately, an improved RVI model for soil moisture estimation was proposed via bare soil model and RVI combined with water cloud model (WCM). 108 soil moisture samples (including jointing, heading and filling stageof winter wheat) were used to estimate and verify the accuracy of the parameters in the WCM, among which 62 samples were used to estimate the empirical parameters of the model, and the remaining 46 samples to verify the accuracy of estimated parameters. Usually, the crop parameters were used to describe the water cloud in the WCM, however, it causes lots of difficulties to apply this model. The crop parameters in improved RVI model were replaced by the RVI to reduce the uncertainty of the WCM. The RVI, instead of the crop parameters, was used to describe the water cloud in WCM, then the soil moisture values estimated by LAI model and improved RVI model were compared with in-situ measured soil moisture values, respectively. The LAI model was verified by LAI obtained in ground measurement and estimated by optical remote sensing data, respectively. To prove the potential applications, the improved RVI model was compared with two LAI models using ground measurement data. Conclusions were drawn based on the comparisons of coefficient of determination (R<sup>2</sup>), root mean square error (RMSE) and mean absolute error (MAE) as follows: 1) The improved RVI model (combined with the WCM, bare soil model and RVI) achieved the best accuracy (R<sup>2</sup>was 0.41, RMSE was 5.7%, MAE was4.7%), the second was the original LAI model (using on ground measured LAI for validation, R<sup>2</sup>was 0.28, RMSE was 7.1%, MAE was 5.1%), while the original LAI model (using optical remote sensing estimated LAI for validation) was the worst (R<sup>2</sup>was 0.14, RMSE was 7.7%, MAE was 6.1%). 2) The improved RVI model, which used polarimetric SAR data and RVI as inputs, provided a convenient and efficient way to estimate the soil moisture. 3) The improved RVI model provided an accurate and rapid method for monitoring soil moisture in various growth stages of winter wheat. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Soil moisture
Controlled terms:Cloud computing - Crops - Decision making - Ecology - Farms - Mean square error - Moisture - Moisture control - Parameter estimation - Polarimeters - Remote sensing - Soil surveys - Soils - Space-based radar - Synthetic aperture radar - Vegetation - Water content
Uncontrolled terms:Coefficient of determination - Environmental conditions - Leaf Area Index - Optical remote sensing data - Radarsat-2 - Soil moisture estimation - Water cloud models - Winter wheat
Classification code:454.3 Ecology and Ecosystems - 483.1 Soils and Soil Mechanics - 716.2 Radar Systems and Equipment - 722.4 Digital Computers and Systems - 731.3 Specific Variables Control - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4 Agricultural Products - 912.2 Management - 922.2 Mathematical Statistics - 941.3 Optical Instruments
Numerical data indexing:Percentage 5.10e+00%, Percentage 5.70e+00%, Percentage 6.10e+00%, Percentage 7.10e+00%, Percentage 7.70e+00%
DOI:10.11975/j.issn.1002-6819.2016.22.020
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 29>
Accession number:20164903093300
Title:Prediction on spatial distribution of soil selenium in typical karst area of southwest China
Authors:Shao, Ya (1, 2); Wang, Yiwei (2); Cai, Chongfa (1); Yang, Shunhua (1); Zhang, Haitao (1)
Author affiliation:(1) College of Resource and Environment, Huazhong Agricultural University, Wuhan; 430070, China; (2) College of Earth Sciences, Guilin University of Technology, Guilin; 541004, China
Corresponding author:Cai, Chongfa(cfcai@mail.hzau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:178-183
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Selenium is an essential micronutrient for animals and humans. Extensive studies have been conducted on distribution of selenium, but seldom studies have been done in Se-enriched, longevity, and karst region. Accurately mapping the spatial distribution of soil Se is the basis for Se-enriched soil utilization, planning, and environmental management. To better understand the Se distribution in the soils in a Se-enriched, longevity, and karst area of China, this study focuses on the total Se in soil in the Guilin Yongfu Baishou river catchment, and 226 soils (0-20 cm) samples were collected by random sampling in 180 km<sup>2</sup>research area in March, 2015. Coordinates and elevations of the sample sites were recorded using a Garmin GPS. Factors affecting the chemical behavior of soil Se were studied to obtain geographical environment factors and related soil properties in the study area through lab analysis and ArcGIS spatial analysis. Auxiliary variables, including soil properties (pH value, soil organic matter, and amorphous iron oxides) and geographical environment factors (elevation, slope, aspect, curvature, compound topographic index, and stream power index) were preliminary selected for predicting total soil Se through stepwise regression. The adjusted determination coefficient (adjusted R<sup>2</sup>) was used to select the regression model, and then elevation, soil organic matter, amorphous iron oxides and compound topographic index were selected as variables. Co-kriging (COK) was used for interpolation of discontinuously distributed auxiliary variables (soil organic matter, amorphous iron oxides), and the correlation coefficient between prediction value and chemical analysis value was used to measure the prediction accuracy of COK. The amorphous iron oxides prediction value showed significant correlation with analysis value (R=0.62, P<0.01). However, the soil organic matter prediction value was no significantly correlated with analysis value in the researched area. In the end, elevation, amorphous iron oxides, and compound topographic index were selected as variables for spatial prediction of soil Se with geographically weighted regression model (GWR). The predicted results of GWR on soil Se were compared with the results obtained from ordinary Kriging (OK), and mean absolute error (MAE) and root mean square error (RMSE) were adopted to validate the prediction of soil Se by these methods. In order to quantify the improvement on prediction precision, a relative improvement (RI) in correlation coefficient was used to measure the improvement on the prediction accuracy of GWR and OK. Compared to OK, the MAE and RMSE of GWR were 0.19 and 0.24, which reduced by 13.64% and 7.69%, respectively. The correlation coefficient between prediction value and chemical analysis value increased from 0.32 to 0.51. The application of GWR resulted in relative improvement (RI) of 59.38%. The study results showed that the precision of total soil Se prediction could be improved if geographical environment factors and related soil properties were properly selected. The problem of discontinuously distributed auxiliary variables could be resolved by COK method. The spatial distribution of soil selenium was related to topography (elevation) and soil property factors (amorphous iron oxides), which had important influence on selenium chemical behavior in soil. Because of the complexity of terrain in the karst area, the correlation coefficient is still low, and it is worth further research. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Soil surveys
Controlled terms:Biogeochemistry - Biological materials - Catchments - Chemical analysis - Environmental management - Forecasting - Geographic information systems - Interpolation - Iron - Iron compounds - Iron oxides - Landforms - Mean square error - Models - Organic compounds - Regression analysis - Selenium - Soils - Spatial distribution - Spatial variables measurement
Uncontrolled terms:Adjusted determination coefficient - Chemical behavior - Co-Kriging - Compound topographic indices - Correlation coefficient - Geographical environment - Geographically weighted regression models - Guilin Yongfu
Classification code:454.1 Environmental Engineering, General - 461.2 Biological Materials and Tissue Engineering - 481.1 Geology - 481.2 Geochemistry - 483.1 Soils and Soil Mechanics - 545.1 Iron - 549.3 Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals - 804.1 Organic Compounds - 804.2 Inorganic Compounds - 903.3 Information Retrieval and Use - 921 Mathematics - 921.6 Numerical Methods - 922.2 Mathematical Statistics - 943.2 Mechanical Variables Measurements
Numerical data indexing:Area 1.80e+08m2, Percentage 1.36e+01%, Percentage 5.94e+01%, Percentage 7.69e+00%, Size 0.00e+00m to 2.00e-01m
DOI:10.11975/j.issn.1002-6819.2016.22.024
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 30>
Accession number:20164903093292
Title:Retrieving winter wheat leaf area index based on unmanned aerial vehicle hyperspectral remote sensing
Authors:Gao, Lin (1, 2, 3, 4, 5); Yang, Guijun (1, 2, 3, 4); Yu, Haiyang (1, 2, 3, 4); Xu, Bo (1, 2, 3, 4); Zhao, Xiaoqing (1, 2, 3, 4); Dong, Jinhui (1, 2, 3, 4, 6); Ma, Yabin (1, 2, 3, 4)
Author affiliation:(1) Beijing Research Center for Information Technology in Agriculture, Beijing; 100097, China; (2) National Engineering Research Center for Information Technology in Agriculture, Beijing; 100097, China; (3) Key Laboratory of Agri-informatics, Ministry of Agriculture, Beijing; 100097, China; (4) Beijing Engineering Research Center of Agricultural Internet of Things, Beijing; 100097, China; (5) School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing; 210023, China; (6) School of Surveying and Land Information Engineering, Henan Polytechnic University, Jiaozuo; 454000, China
Corresponding author:Yang, Guijun(yanggj@nercita.org.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:113-120
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Leaf area index (LAI) is the important vegetation parameter, which is the basis to monitor crop growth and predict crop yield and used widely in many applications. Remote sensing techniques are known to be effective, inexpensive and non-destructive methods for estimating the LAI of crop canopies. And unmanned aerial vehicle (UAV) hyperspectral remote sensing technology as a new method for obtaining agricultural resources, crop growth and other information, can bring new opportunities for LAI dynamic monitoring. As is known to all, spectral characteristic parameters are extremely important for hyperspectral remote sensing in tracking the LAI of crop. However, the research about retrieving the LAI based on UAV hyperspectral remote sensing is rarely reported. And few studies based on spectral characteristic parameters in estimating LAI by using UAV hyperspectral data have been done. In this paper, we carried out the sky-to-ground remote sensing experiments used ASD Field SpecFR Pro 2500 spectroradiometer (ASD) and Cuber UHD185 Firefly imaging spectrometer (UHD185) in winter wheat experimental field. And we acquired two synchronal data including UAV hyperspectral remote sensing data and in-field data for 3 critical growth stages i.e. booting stage, anthesis stage and filling stage. So we retrieved the winter wheat LAI by using the acquired data. Firstly, we regarded the ASD hyperspectral data as the standard spectral data for evaluating UHD185 hyperspectral data. And we evaluated UHD185 data from 3 aspects, i.e. the spectral curve trend, the spectral correlation and the target objects' spectral differences. It demonstrated that the UHD185 spectrums from 458 to 830 nm were reliable data, which could be used to monitor LAI and provide the basis for using UHD185 hyperspectral data in future. Furthermore, we calculated 12 kinds of spectral characteristic parameters, which were 4 red edge parameters including the red edge position (REP), the red edge amplitude (Dr), the red edge area (SDr), and the ratio of the red edge amplitude to the minimum amplitude (Dr/Dr<inf>min</inf>), and 8 spectral indices including the normalized difference vegetation index (NDVI), the optimized soil-adjusted vegetation index (OSAVI), the triangular vegetation index (TVI), the modified soil-adjusted vegetation index (MSAVI), the modified triangular vegetation index (MTVI1), the modified chlorophyll absorption ratio index 2 (MCARI<inf>2</inf>), the normalized difference spectral index (NDSI), and the ratio spectral index (RSI). And we analyzed the correlation between the spectral characteristic parameters and the LAI. The results showed that the RSI<inf>(494,610)</inf>was highly positively correlated with the LAI and better in retrieving the LAI than the others. Meanwhile, a linear regression model created based on the l g (RSI) exhibited that the l g (RSI) and l g (LAI) had the optimum linearity relationship (R<sup>2</sup>=0.737, n=103). And the predictive l g (LAI) had the high fitting with the measured l g (LAI) (R<sup>2</sup>=0.783, RMSE=0.127). Therefore, this study confirmed the UAV hyperspectral remote sensing was feasible in estimating winter wheat LAI. It can provide the evidence for developing UAV hyperspectral remote sensing application in agriculture. Moreover, the results also provide a powerful evidence to develop the integration of multiple remote sensing platforms based on satellites, aviation, UAVs and ground objects in precision agriculture. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:35
Main heading:Remote sensing
Controlled terms:Agriculture - Crops - Linear regression - Nondestructive examination - Optical waveguides - Regression analysis - Sensors - Spectrometers - Unmanned aerial vehicles (UAV) - Vegetation - Vehicles
Uncontrolled terms:Hyperspectral remote sensing - Hyperspectral remote sensing data - Hyperspectral remote sensing technology - Leaf Area Index - Normalized difference vegetation index - Red edge parameters - Remote sensing techniques - Spectral indices
Classification code:652.1 Aircraft, General - 741.3 Optical Devices and Systems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4 Agricultural Products - 922.2 Mathematical Statistics
Numerical data indexing:Size 4.58e-07m to 8.30e-07m
DOI:10.11975/j.issn.1002-6819.2016.22.016
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 31>
Accession number:20164903093311
Title:Time sequence division of high-standard prime farmland construction area
Authors:Li, Fazhi (1); Sun, Hua (1); Jiang, Tingmei (2); Zhu, Gaoli (1); Zhang, Jian (1)
Author affiliation:(1) College of Public Administration, Nanjing Agricultural University, Nanjing; 210095, China; (2) Shandong Guanghe Real Estate and Land Appraisal Co., Ltd., Jinan; 250000, China
Corresponding author:Sun, Hua(sh@njau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:251-258
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The construction of high-standard prime farmland is an important measure to protect the cultivated land and ensure the food safety in China. Researchers have gained abundant achievements in this field, however, the previous methods may not be appropriate to analyze the construction of high-standard prime farmland in the alluvial plain of Yellow River. Firstly, the indices were redundant and it was difficult to determine the weights because the cultivated land in the alluvial plain of Yellow River had the overall flat terrain and got the similar natural quality. Secondly, the existing Classification and grading of cultivated land natural quality was not accurate due to the evaluation system and the method. Thirdly, it's difficult to choose appropriate evaluation units, and the existing evaluation units such as administrative villages, land use patches and grid cells had different applicable conditions. This paper took Shanghe County, Shandong Province as the research area, and the detailed research process could be described as follows: 1) We constructed the cultivated land quality evaluation system, including the natural quality, the space form and the infrastructure of the land; 2) We defined the evaluation units (1'×1', a total of 487 units) by the longitude and latitude grid, and calculated the values of units and graded the indices according to equally spaced reference; 3) We determined the weights by the entropy weight method, and evaluated the comprehensive quality of cultivated land; 4) We graded the time sequence of the high-standard prime farmland construction and allocated the scores to the land pattern spots. Results showed that the suitable construction area with the time sequence of the first, the second, the third and the fourth level accounted for 7.83%, 69.10%, 22.93% and 0.14% respectively, in which the construction areas with the time sequence of the first and second level were mainly distributed in the north and west, while the third and fourth level mainly in the south. However, according to the Classification and grading of cultivated land natural quality, the land with the natural quality of Grade 5 accounted for 13.34% of total area and was mainly distributed in the south, the land of Grade 6 accounted for 76.27% and was mainly distributed in the central part, and the land of Grade 7 and 8 accounted for 10.40% and was mainly distributed in the south. There were distinct differences between the two results, which indicated that the method and the evaluation system in this paper could significantly improve the evaluation accuracy. We can draw the conclusion that when there is no significant difference for the overall natural qualities of cultivated land, the division result would be completely different if we take into account the high-standard prime farmland construction standard that it should be appropriate with the modern agricultural production and operation modes, which also indicates the necessity to land's scale management in the modernized agriculture of China. This research provides a new idea for the region division of high-standard prime farmland construction's time sequence, as well as offered a reference for the construction of high-standard prime farmland in alluvial plain of Yellow River. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:23
Main heading:Quality control
Controlled terms:Agriculture - Farms - Grading - Land use - Landforms - Rivers - Zoning
Uncontrolled terms:Agricultural productions - Comprehensive qualities - Construction standards - Cultivated land qualities - Cultivated lands - Grid methods - High standards - Time sequences
Classification code:403 Urban and Regional Planning and Development - 481.1 Geology - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 913.3 Quality Assurance and Control
Numerical data indexing:Percentage 1.04e+01%, Percentage 1.33e+01%, Percentage 1.40e-01%, Percentage 2.29e+01%, Percentage 6.91e+01%, Percentage 7.63e+01%, Percentage 7.83e+00%
DOI:10.11975/j.issn.1002-6819.2016.22.035
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 32>
Accession number:20164903093308
Title:Biogas production of fruit and vegetable wastes two-phase fermentation by batch and continuous feeding
Authors:Feng, Jing (1); Zhang, Yuhua (1); Luo, Juan (1); Qi, Yue (1)
Author affiliation:(1) Key Laboratory of Energy Resource Utilization from Agricultural Residues, Ministry of Agriculture, Chinese Academy of Agricultural Engineering, Beijing; 100125, China
Corresponding author:Zhang, Yuhua(zhangyuhua@vip.sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:233-238
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:This study evaluated the biogas production of apple fruit wastes and vegetable wastes using batch test and continuous fermentation test. The biogas production of the mixtures of fruit wastes and vegetable waste with different mixing ratios (Fruit: Vegetable, F:V) was also evaluated. For the batch tests, the F:V was set as 5:0, 4:1, 1:1, 1:4, 0:5, respectively. The batch tests were employed for the evaluation of the biogas production process and the accumulated biogas production of these wastes, which were conducted with 500 mL digesters. During these tests, daily biogas productions were recorded. The results showed that the biogas production values of the mixture of vegetable and apple waste were significantly higher than those of fruit waste or vegetable wastes digested singly at 38℃, which suggested that synergistic effects occurred during the anaerobic digestion of the vegetable wastes mixed with fruit wastes. When the F:V was 4:1, the biogas production of the mixture of fruit wastes and vegetable wastes reached 914.6 L/kg, which was the highest among all the 5 tests. The modified Gompertz model had been proved well for fitting the accumulated biogas production curves of batch digestion of wastes. In this study, the modified Gompertz model was employed to fit the accumulated biogas production curves of the vegetable wastes, fruit wastes and their mixtures. The R<sup>2</sup>values of the fitting curves ranged from 0.983 to 0.999, which was similar with the results of the literatures. This meant that the modified Gompertz model fitted the accumulated biogas production curves of fruit and vegetable wastes well. The continuous tests were conducted with the combined two-phase (CTP) reactors at 38℃, and the F:V values were 4:1 and 1:4, respectively. The hydraulic retention time (HRT) of the reactors was controlled in 24 d by adjusting the reflux of biogas slurry to the reactors. In general, the daily reflux of biogas slurry was about 400 mL. The organic loading rate (OLR) of the CTP reactors was 0.5 g/(L·d) during the first 18 days, and it rose to 1.5 and 2.5 g/(L·d) during the next days. The results showed that the OLR of CTP could reach 2.5 g/(L·d) when treating fruit wastes and vegetable wastes. Under this OLR, the daily biogas production and specific biogas production respectively reached 12.9 and 0.39 L/g. These results showed that the CTP reactor could be employed to treat fruit and vegetable waste for biogas production. However, the digestion rate of fruit and vegetable waste in CTP reactor was lower than continuous stirred-tank reactor, though the CTP reactor had simple structure and low cost. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Biogas
Controlled terms:Anaerobic digestion - Curve fitting - Fermentation - Fruits - Mixtures - Pulp digesters - Testing - Vegetables - Wastes
Uncontrolled terms:Batch tests - Biogas production - Continuous fermentation - Continuous stirred tank reactor - Fruit and vegetable waste - Hydraulic retention time - Specific biogas productions - Two-phase reactor
Classification code:522 Gas Fuels - 811.1.2 Papermaking Equipment - 821.4 Agricultural Products - 921.6 Numerical Methods
Numerical data indexing:Age 4.93e-02yr, Specific_Volume 3.90e-01m3/kg, Specific_Volume 9.15e-01m3/kg, Volume 4.00e-04m3, Volume 5.00e-04m3
DOI:10.11975/j.issn.1002-6819.2016.22.032
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 33>
Accession number:20164903093283
Title:Experiment and analysis on test device of corn ear picking by pulling stalk upwards
Authors:Cheng, Xiupei (1); Jia, Xiaodong (2); Chen, Meizhou (1); Li, Qiyun (1)
Author affiliation:(1) School of Agricultural and Food Engineering, Shandong University of Technology, Zibo; 255000, China; (2) College of Science, Shandong Jianzhu University, Jinan; 250000, China
Corresponding author:Li, Qiyun(liqiyun@sdut.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:50-55
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In recent years, corn has become the first major crop in place of wheat and rice, which has an important influence on the national life with its production increasing. Corn snapping device is a main component of corn harvesting machine, and has an important effect on the quality of corn harvest. Currently, according to the way of working, there are 2 types of snapping devices: snapping rolls and plate type. The existing snapping device is easy to cause the corn ear nibbling and grain loss. In order to solve the above problems, the test device of corn ear picking by pulling stack upwards was studied, the principle of which was imitating artificial snapping action, and pulling stalk upwards to pick corn. It mainly included corn ear picking device, clamping feeding device, corn roots cutting device, high-speed photography and computer data acquisition system. When corn plant was fed to the ear picking device by the clamping feeding device, the corn stalks were cut off through the corn roots cutting device, then the snapping rollers pulled up the corn stalks and the corn ear encountered the snapping rollers, and finally the corn ear was bent and broken off. In the process of picking corn ears, the force of stalk was a resultant force of the force of pick ear buckle and the force along spiral line, which made stalk move backward and upward. This paper also analyzed the force relationship of corn ear. When the corn ear encountered the snapping rollers, the snapping rollers only overcame connection force and connection torque to bend and break off the corn ear. The test was done at the laboratory of agricultural machinery. The grain moisture content was 21%, and the grain loss rate was taken as the index to estimate the performance of the harvesting device. Through the single factor experiment, the impacts of the roll's rotational speed, the roll's interval and the angle between roll and horizontal surface on the rate of grain loss were analyzed. The process of harvesting was captured through the high-speed photography, which was helpful to the comprehensive analysis in the late period. Through the single factor experiment and the analysis of variance, it was found that the grain loss rate reduced at first and then increased gradually, when the rotational speed was changed in 6 levels of 500, 600, 700, 800, 900 and 1000 r/min in turn and other factors were changeless. The rotational speed had significant effect on the grain loss by the analysis of variance. The average grain loss rate was the least (0.293%) when the rotational speed was 700 r/min. When the roll's interval was selected to 5 levels including 4, 6, 8, 10 and 12 mm in turn, the grain loss rate was decreasing gradually in general. The grain loss rate was the least when the roll's interval was 10 mm, which was 0.33%. But, if the interval was too large, it had some problems such as the grasping ability was weakened and the corn head was gripped. The effect of the angle between roll and horizontal surface on the grain loss rate was not obvious, which was set at 5 levels of 0°, 10°, 20°, 30° and 40°, and the grain loss rate was 0.28%-0.31%. It was found that corn ear picking by pulling stalk upwards had good performance, and the corn grain loss rate was less than the national industry standard (2%) and also less than the traditional snapping roller. This way of picking corn can improve the corn grain quality and reduce the grain loss, and provide a thought for corn harvesting. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:21
Main heading:Grain (agricultural product)
Controlled terms:Agricultural machinery - Agriculture - Crops - Data acquisition - Experiments - Factor analysis - Harvesters - Harvesting - High speed photography - Photography - Rollers (machine components) - Speed
Uncontrolled terms:Comprehensive analysis - Computer data acquisition system - Corn - Device of corn ear picking by pulling stalk upwards - Experiment and analysis - Grain loss - Single-factor experiments - Variance analysis
Classification code:601.2 Machine Components - 723.2 Data Processing and Image Processing - 742.1 Photography - 746 Imaging Techniques - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 901.3 Engineering Research - 922.2 Mathematical Statistics
Numerical data indexing:Percentage 2.00e+00%, Percentage 2.10e+01%, Percentage 2.80e-01% to 3.10e-01%, Percentage 2.93e-01%, Percentage 3.30e-01%, Rotational_Speed 1.00e+03RPM, Rotational_Speed 7.00e+02RPM, Size 1.00e-02m, Size 1.20e-02m
DOI:10.11975/j.issn.1002-6819.2016.22.007
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 34>
Accession number:20164903093298
Title:Suitable nitrogen application reducing N<inf>2</inf>O emission and improving grain yield in wheat-maize crop rotation system in Beijing suburb
Authors:Shan, Nan (1, 2); Zhao, Tongke (2); Bi, Xiaoqing (2); An, Zhizhuang (2); Zhao, Liping (2); Zhang, Huaiwen (3); Du, Lianfeng (2)
Author affiliation:(1) College of Resources and Environmental Sciences, China Agricultural University, Beijing; 100193, China; (2) Institute of Plant Nutrition and Resources, Beijing Academy of Agriculture and Forestry Sciences, Beijing; 100097, China; (3) Shunyi District Institute of Agricultural Sciences, Beijing; 101300, China
Corresponding author:Du, Lianfeng(dulianfengyzs@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:163-170
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Nitrous oxide (N<inf>2</inf>O) has been recognized as one of the most important trace gases in the atmosphere that causes global warming and stratospheric ozone depletion. Nitrogen (N) fertilizer is considered as the primary source of N<inf>2</inf>O emissions from agricultural soils. N<inf>2</inf>O production and emission processes are influenced by a number of soil and environmental variables, interacting of soil water and N processes, crop uptake and management practices. As a large agricultural country, China consumes the greatest amount of synthetic N fertilizer which accounts for 30% of the world consumption. Therefore, quantifying N<inf>2</inf>O emissions from agricultural soils and seeking suitable mitigation measures have become a relatively hot issue in international global climate change studies. It is a great challenge to guarantee high crop yields while reducing N<inf>2</inf>O emissions under high input of N fertilizers (e.g., N fertilizer application rate can be as high as 600 kg/hm<sup>2</sup>in the North China Plain). However, few field data sets are available for the exploration of the effects of fertilizer N regimes on soil N<inf>2</inf>O emission in Beijing suburb, one of the regions with the most intensive agriculture in North China Plain. The main objectives of this research were to identify the characteristics of N<inf>2</inf>O emission from winter wheat-summer maize rotation land in Beijing suburb, and to seek a way that could decrease N<inf>2</inf>O emission and increase or keep crop yield. N<inf>2</inf>O exchange fluxes from the intensively cultivated winter wheat-summer maize rotation system in Beijing suburb, Fangshan District, were measured by the static chamber technique under 8 levels of N treatments from October 13, 2012 to September 28, 2013. Eight treatments with 3 replications (each micro-plot was 80 cm in diameter and 0.5 m<sup>2</sup>in area) were contained in the experiment: N0 (0 kg/hm<sup>2</sup>), N1 (50 kg/hm<sup>2</sup>), N2 (100 kg/hm<sup>2</sup>), N3 (150 kg/hm<sup>2</sup>), N4 (200 kg/hm<sup>2</sup>), N5 (250 kg/hm<sup>2</sup>), N6 (300 kg/hm<sup>2</sup>), and N7 (400 kg/hm<sup>2</sup>) respectively for each crop field. The results indicated that the cumulative emissions of N<inf>2</inf>O from 8 levels of N treatments were 0.08-0.52 kg/hm<sup>2</sup>(winter wheat) and 0.26-3.70 kg/hm<sup>2</sup>(summer maize), respectively. The N<inf>2</inf>O emission during the wheat growing season from 8 levels of N fertilization treatments accounted for 0.05%-0.13% of the total N loss, and during the maize growing season were 0.78%-1.02%, which indicated that the emission of N<inf>2</inf>O mainly occurred during the maize growing season. It was obvious that the application of existing chemical fertilizers showed significantly seasonal and diurnal variation on the N<inf>2</inf>O emissions in wheat-maize rotation system in the suburbs of Beijing. Considering fertilizer rates, N<inf>2</inf>O emission and crop yield, it was concluded that the fertilization rate of N4 (200 kg/hm<sup>2</sup>) for each crop was very reasonable, which could provide the basis for applying fertilizer rationally, reducing farm production costs, estimating greenhouse gas emissions from cropland and compiling national greenhouse gases emission inventory. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:35
Main heading:Nitrogen fertilizers
Controlled terms:Agriculture - Climate change - Crops - Cultivation - Emission control - Fertilizers - Gas emissions - Global warming - Greenhouse gases - Landforms - Nitrogen - Nitrogen oxides - Ozone layer - Rotation - Soil moisture - Soils
Uncontrolled terms:Beijing suburb - Crop rotation - Fluvo-aquic soils - Greenhouse gases emissions - Nitrous oxide - Seasonal and diurnal variations - Static chamber technique - Stratospheric ozone depletion
Classification code:443.1 Atmospheric Properties - 451.1 Air Pollution Sources - 451.2 Air Pollution Control - 481.1 Geology - 483.1 Soils and Soil Mechanics - 804 Chemical Products Generally - 804.2 Inorganic Compounds - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 931.1 Mechanics
Numerical data indexing:Area 5.00e-01m2, Percentage 3.00e+01%, Percentage 5.00e-02% to 1.30e-01%, Percentage 7.80e-01% to 1.02e+00%, Size 8.00e-01m
DOI:10.11975/j.issn.1002-6819.2016.22.022
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 35>
Accession number:20164903093297
Title:Impact of water-nitrogen coupling on grain yield, water and nitrogen usage in zeolite-amended paddy field under alternate wetting and drying irrigation
Authors:Chen, Taotao (1); Sun, Dehuan (2); Zhang, Xudong (1); Wu, Qi (1); Zheng, Junlin (1); Chi, Daocai (1)
Author affiliation:(1) College of Water Resources, Shenyang Agricultural University, Shenyang; 110866, China; (2) Donggang Experimental Station of New Irrigation Technology, Donggang; 118300, China
Corresponding author:Chi, Daocai(daocaichi@vip.sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:154-162
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Increasing demand for maintaining yield with reducing environmental and resource costs challenges conventional rice production. Water inputs can be reduced by the use of alternate wetting and drying (AWD) irrigation. And clinoptilolite zeolite (CZ) benefits farmers through decreasing water inputs and N usages in non-irrigated farmland, however, its performance is rarely reported in paddy field, especially under AWD irrigation. In order to clarify the application potential of CZ under AWD irrigation, an experiment was conducted under automatic canopy lysimeters to determine the effects of CZ on rice grain yield and water and nitrogen usage efficiency under different nitrogen application rates and irrigation regimes using the split-split-split plot design. The experimental site was located at the Donggang Experimental Station of New Irrigation Technology, Dandong, China in 2012 and 2013. A japonica rice, Oryza sativa L. cv. Gangyu 6 was cultivated on a silty loam soil. Years after zeolite application were main plots. Two irrigation regimes, continuous flooding and AWD irrigations, were subplots. N application rates (0, 52.5, 105 and 157.5 kg/hm<sup>2</sup>N applied as urea) were sub-subplots and CZ application rates (0, 5, 10 and 15 t/hm<sup>2</sup>CZ) were sub-sub-sub plots. The experiment was repeated in 2013 but no additional CZ was received, and the plots in 2013 experiment were same as 2012 experiment. Dynamics of soil moisture characteristic curves under different rates of zeolite application were also observed through mixing surface soil samples attained from the experimental site with 0, 5, 10 and 15 t/hm<sup>2</sup>in the laboratory. Results indicated that paddy field amended with increasing rates of CZ application significantly increased soil water holding capacity, and improved paddy soil moisture status, when the soil moisture status of paddy surface soil was controlled within the range of -35-0 kPa. At the soil matrix potential of -20 kPa, soil application of 5-15 t/hm<sup>2</sup>rates of CZ resulted in 3.0%-6.1% higher volumetric soil water content than zero CZ treatment. The increasing of soil water holding capacity resulted in enhanced water productivity in both continuous flooding and AWD irrigations, while the latter was more obvious. Increasing rate of CZ application significantly improved soil cation exchange capacity and nutrient preserving capability, In particular, the application rate of 105 kg/hm<sup>2</sup>nitrogen fertilizer application mixed with 10-15 t/hm<sup>2</sup>CZ could significantly improve nitrogen utilization efficiency by 76.8%-87.0% while maintaining normal rice yield. Increasing CZ application also increased grain yield by 4.7%-16.8%, and overcome a slight reduction in grain yield under AWD irrigations at the highest nitrogen rate, as compared to continuous flooding irrigation with the same nitrogen rate. In general, AWD irrigation in combination with 10 t/hm<sup>2</sup>CZ and 105 kg/hm<sup>2</sup>nitrogen fertilizer application was recommended. This rice production system could benefit farmers through reducing 27.8% irrigation water, 33.3% nitrogen application, while increasing 10.6% rice yield, 89.2% nitrogen use efficiency and 52.5% water productivity and these positive effects could last at least 2 years. The proposed production system was also expected to be an available strategy for ecological agriculture for arid and semi-arid area which maintains yield with lower environmental and resource costs by enhancing soil water holding capacity and improving nutrient preserving capability in paddy field due to CZ application. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:37
Main heading:Nitrogen fertilizers
Controlled terms:Agriculture - Drying - Efficiency - Fertilizers - Floods - Grain (agricultural product) - Irrigation - Moisture - Nitrogen - Nutrients - Positive ions - Productivity - Soil moisture - Soil surveys - Soils - Urea - Water resources - Wetting - Zeolites
Uncontrolled terms:Cation exchange capacities - Rice - Soil water holdings - Water productivity - WETTING AND DRYING
Classification code:444 Water Resources - 483.1 Soils and Soil Mechanics - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 913.1 Production Engineering
Numerical data indexing:Age 2.00e+00yr, Percentage 1.06e+01%, Percentage 2.78e+01%, Percentage 3.00e+00% to 6.10e+00%, Percentage 3.33e+01%, Percentage 4.70e+00% to 1.68e+01%, Percentage 5.25e+01%, Percentage 7.68e+01% to 8.70e+01%, Percentage 8.92e+01%, Pressure -2.00e+04Pa, Pressure -3.50e+04Pa
DOI:10.11975/j.issn.1002-6819.2016.22.021
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 36>
Accession number:20164903093316
Title:Optimization of compound enzymes solution pretreatment for improving germinated brown rice yield
Authors:Jia, Fuguo (1); Jiang, Longwei (1); Zhang, Yaxiong (1); Cao, Bin (1); Zeng, Yong (1)
Author affiliation:(1) College of Engineering, Northeast Agricultural University, Harbin; 150030, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:289-295
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The purpose is to solve the problems about long soak time of germinated brown rice as well as low production efficiency in traditional production process. A novel processing technology is developed using compound enzyme solution pretreatment with cellulase and xylanase rather than distilled water soak brown rice during the process of producing germinated brown rice. The brown rice's tough cortex is mainly caused by the coarse fiber structure, whose major components are cellulose and araboxylan. The xylan layer with its covalent linkage to lignin and its noncovalent interaction with cellulose may play a significant role in maintaining the integrity of the cellulose in situ and protecting the fibers against degradation by cellulases. Using compound enzyme pretreatment to degrade some cortex resulted in a significant increase in water absorption rate over brown rice. What's more, the brown rice obtained a suitable water content to sprout in a much shorter time. By shortening the soak time, it could improve the efficiency of germinated brown rice production. Brown rice degraded some cortex during soaking, which thereby reduced the block of cortex to water. Compared with soaking methods, the new method not only reduced the soak time but also improved the germinated rate. Beyond that, a central composite rotatable orthogonal experimental design of response surface methodology with 4 factors and 5 levels was employed. Taking raw material of brown rice, the influences of the 4 parameters including enzyme treatment time, enzyme treatment temperature, concentration of compound enzyme solution, percentage of cellulase quality on the germinated brown rice yield as well as the optimal parameters of this process were investigated. Additionally, mathematical models for the influences of various parameters on the germinated brown rice yield were set up. As shown, the mathematical models for the germinated brown rice yield were extremely significant (P<0.01). Meanwhile, the optimum process parameters for maximizing the germinated brown rice yield were 0.57 g/L of enzyme concentration, 35℃ of enzyme treatment temperature, 135 min of enzyme treatment time and 1.86:1 of cellulose-to-xylanase mass ratio, respectively. Moreover, the germinated brown rice yield and the content of γ-aminobutyric acid (GABA) under the optimum parameters were 3.90% and 3.86 mg/(100 g), which was higher than that of germinated brown rice produced by soaking method. Compared with conventional soaking method, compound enzyme pretreatment method significantly shortened the time of water absorption (135 min), in which soak time was reduced by 62.5%. As a result, it greatly improved the efficiency of germinated brown rice production. Through enzymatic soaking pretreatment, seed germination can be promoted. Brown rice has the characteristic of seed. Compound enzymatic soaking pretreatment will not only wake up the dormancy of brown rice but also improve the activity of endogenous enzyme to bud. GABA in germinated brown rice is produced by glutamic acid, and it removes carboxyl under the effect of glutamate decarboxylase (GAD). Moreover, the activity of GAD is closely related to the accumulation of GABA. The optimum pH of GAD is acidity. The brown rice soaked in acidic environment of compound enzyme solution increases the activity of GAD, which will be conducive to generation of GABA. Surface structure of the germinated brown rice degraded by enzyme was studied by Scanning Electron Microscopy. Microstructure of brown rice cortex confirmed that part of the cortex degraded because the brown rice soaked in compound enzymes solution. Furthermore, hydration characteristics of brown rice under different soaking conditions showed that the water absorption rate of brown rice soaked in compound enzyme solution was significantly faster than that soaked in distilled water. Starch in the endosperm was easier to combine with water molecules, and brown rice with a suitable water content to sprout in a much shorter time was obtained. By utilizing the technology described in this paper, the research results can provide a reference to improve industrial production of germinated brown rice. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:35
Main heading:Water absorption
Controlled terms:Amino acids - Cellulose - Efficiency - Enzyme activity - Enzymes - Industrial research - Ions - Mathematical models - Molecules - Optimization - Scanning electron microscopy
Uncontrolled terms:Gamma-aminobutyric acids - Germinated brown rice - Glutamate decarboxylase - Hydration characteristics - Non-covalent interaction - Orthogonal experimental design - Pre-Treatment - Response surface methodology
Classification code:461.9 Biology - 802.3 Chemical Operations - 804.1 Organic Compounds - 811.3 Cellulose, Lignin and Derivatives - 901.3 Engineering Research - 913.1 Production Engineering - 921.5 Optimization Techniques - 931.3 Atomic and Molecular Physics
Numerical data indexing:Mass 1.00e-01kg, Mass_Density 5.70e-01kg/m3, Percentage 3.90e+00%, Percentage 6.25e+01%, Time 8.10e+03s
DOI:10.11975/j.issn.1002-6819.2016.22.040
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 37>
Accession number:20164903093280
Title:Movement law of maize population in seed room of seed metering device based on discrete element method
Authors:Zhang, Tao (1); Liu, Fei (1); Zhao, Manquan (1); Liu, Yueqin (1); Li, Fengli (1); Chen, Chen (1); Zhang, Yong (1)
Author affiliation:(1) College of Mechanical and Electrical Engineering, Inner Mongolia Agricultural University, Hohhot; 010018, China
Corresponding author:Zhao, Manquan(nmgzhaomq@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:27-35
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Development of conservation tillage can improve the ecological environment in alpine arid area of northern China and farming and animal husbandry interlaced zone, conducive to the sustainable development of China agriculture. Due to the regional difference of conservation tillage, developing a precise no-tillage planter suitable for alpine arid area has an important significance for farming and animal husbandry interlaced zone in increasing surface coverage and reducing water loss and soil erosion. As the surface under conservation tillage has a certain amount of straw and stubble, vibration characteristic of planter is different from common cultivation during the operation, and the vibration has great influence on the movement state of seed population. Population movement state affects seed suction performance of air-suction seed metering device, thus influencing the quality of whole operation of no-tillage planter. When the vibration is small, population movement speed is low, liquidity is poor, and suction hole re-suction rate is relatively high; when the vibration is large, population movement speed is high, and it is difficult to suck seeds for suction hole and the leakage rate is relatively high; proper vibration can reduce the leakage rate and the re-suction rate of suction hole. Therefore, for no-tillage surface planting in alpine arid area, metering device vibration and population movement state have great influence on seed suction performance of air-suction seed metering device. The paper aims to study the influence law of vibration parameters of seed metering device on corn population movement in seed metering device during no-tillage surface operation with air-suction no-tillage planter. This paper adopts the BK acceleration sensor and Pulse LAN-XI vibration test system for testing vibration characteristics of seed metering device during no-tillage surface operation with 2BM-5 air-suction no-tillage planter, and the analysis on time domain and frequency domain of vibration signal is conducted with the MATLAB software. Then the time domain and frequency domain results are taken as input parameters of seed metering device model in discrete element software, and the movement law of maize populations under the condition of vibration is simulated in the field work of no-till planter. Seed suction performance bench test verification is performed with the JPS-12 computer vision test bench and LKD-P type suction electromagnetic vibration table, and the analysis on seed metering performance of air-suction seed metering device is conducted under different operation speed and vibration amplitude. Field vibration signal analysis results show that when the field operation speed of planter increases from 2 to 7 km/h, the frequency of the main vibration power of seed metering device is basically kept at 5, 6 and 7 Hz; the vibration amplitude of the seed metering device shows a linear increase from 2.4 to 7.9 mm. Discrete element method simulation results show that the fitting curve between the maximum speed of corn population in seed room and the forward speed of planter has a fitting determination coefficient (R<sup>2</sup>) of 0.9671. The fitting straight line between the average speed of corn population and the speed of planter has a fitting determination coefficient (R<sup>2</sup>) of 0.9325. Bench test results show that the operation speed for good seed metering performance of the air-suction seed metering device is 3-5 km/h, and the good vibration amplitude is 6 mm; the maximum speed range of the population is 0.1203-0.2243 m/s, the population average speed range is 0.0807-0.1413 m/s, the maximum speed range of the population in seed suction area is 0.127-0.26 m/s, and the air-suction seed metering device has a good performance. The results can provide theoretical basis for improving the seed suction performance of air-suction seed metering device of no-tillage planter. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Seed
Controlled terms:Agricultural machinery - Agriculture - Animals - Arid regions - Computer vision - Crops - Cultivation - Curve fitting - Finite difference method - Frequency domain analysis - MATLAB - Nobelium - Pneumatic materials handling equipment - Software testing - Soil conservation - Speed - Sustainable development - Time domain analysis - Vibration analysis
Uncontrolled terms:Determination coefficients - Discrete element method simulations - Electromagnetic vibrations - No-tillage planter - Population movement - Seed metering devices - Vibration signal analysis - Vibrations
Classification code:443 Meteorology - 444 Water Resources - 483.1 Soils and Soil Mechanics - 622.1 Radioactive Materials, General - 632.4 Pneumatic Equipment and Machinery - 723.5 Computer Applications - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921 Mathematics
Numerical data indexing:Size 2.40e-03m to 7.90e-03m, Velocity 1.20e-01m/s to 2.24e-01m/s, Velocity 1.27e-01m/s to 2.60e-01m/s, Velocity 5.56e-01m/s to 1.94e+00m/s, Velocity 8.07e-02m/s to 1.41e-01m/s, Velocity 8.33e-01m/s to 1.39e+00m/s
DOI:10.11975/j.issn.1002-6819.2016.22.004
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 38>
Accession number:20164903093294
Title:Establishment and application of sediment diffusion coefficient model based on influence of particle dynamic scale
Authors:Zhang, Zichao (1); Chen, Xin (1, 2); Wang, Fujun (1, 2); Xiao, Ruofu (1, 2)
Author affiliation:(1) College of Water Resources & Civil Engineering, China Agricultural University, Beijing; 100083, China; (2) Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System, Beijing; 100083, China
Corresponding author:Chen, Xin(chenx@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:129-137
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:On the basis of eddy viscosity coefficient theory, the semi-empirical sediment diffusion coefficient models are used widely to calculate the volume concentration of solid phase in the Eulerian two-phase flow simulation. However, the diffusion coefficient models' accuracy is not enough because the particle dynamic scale influence on the fluid turbulence intensity is ignored when they are applied to suspended load sediment two-phase flow simulation. Thus the fluid turbulence intensity change rate function about particle dynamic scale and solid volume concentration was derived, and a new sediment diffusion coefficient model was established in the present study. The new model was called DC-PDPC model. The function derivation was based on the semi-empirical eddy viscosity coefficient model, the particle-eddy interaction theory about the influence of the particle dynamic scale and solid concentration on the fluid turbulence intensity, the equilibrium flow theory and the multivariate regression theory with data. The suspended load sediment two-phase flow simulations were conducted in a circular tube. The results showed that the maximum relative error of relative solid phase volume concentration between the experiment and the calculated values by NON-DC model was 90%-120% and the error was 10%-25% for Diffusion-in-VOF model under different flow conditions. The simulation precision was low, because change of the sediment diffusion coefficient was not considered due to ignoring the particle dynamic scale and solid phase volume concentration influence on the fluid turbulence intensity. In different cases, the relative error between the experiment and the calculation by the three type models (Diffusion-in-VOF, NON-DC and DC-PDPC) were all high near the wall of the tube. When the particle dynamic scale was less than or equal to 1, the maximum relative error of relative solid phase concentration between the experiment and the calculation by the new DC-PDPC model was less than 10%, which was much less than the value of the other models. When the particle dynamic scale was more than 1, the maximum relative error of relative solid phase concentration were all less than 10% for Diffusion-in-VOF model and DC-PDPC model, because the formula expressions of both models were the same under this condition. By comparison with the other models, the new sediment diffusion coefficient model could better reflect the influence of the particle dynamic scale on sediment diffusion coefficient under different flow conditions. Along with the change of the solid phase concentration distribution caused by DC-PDPC model, the solid phase velocity distribution and the liquid phase velocity distribution all changed. The changing trend of the solid and liquid phase velocity distribution were closely related to the changing trend of the solid phase concentration distribution, but the change in the solid phase velocity and liquid phase velocity was small compared with change in solid phase concentration. The new DC-PDPC model can be accurately applied to the suspended load sediment solid-liquid two-phase flow field with obviously improved accuracy of flow field. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Two phase flow
Controlled terms:Computation theory - Diffusion - Diffusion in liquids - Elementary particles - Errors - Flow fields - Flow simulation - Fluids - Liquids - Microchannels - Phase velocity - Regression analysis - Sediments - Suspended sediments - Turbulence - Velocity - Velocity distribution - Viscosity
Uncontrolled terms:Computational model - Eddy viscosity coefficients - Liquid phase velocity distributions - Maximum relative errors - Sediment diffusion coefficients - Solid-liquid two phase flows - Solid-phase concentration - Suspended loads
Classification code:483 Soil Mechanics and Foundations - 631.1 Fluid Flow, General - 711.1 Electromagnetic Waves in Different Media - 721.1 Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory - 922.2 Mathematical Statistics - 931.3 Atomic and Molecular Physics
Numerical data indexing:Percentage 1.00e+01%, Percentage 1.00e+01% to 2.50e+01%, Percentage 9.00e+01% to 1.20e+02%
DOI:10.11975/j.issn.1002-6819.2016.22.018
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 39>
Accession number:20164903093315
Title:Influence of screen parameters optimization on screening efficiency of feed hammer mill
Authors:Cao, Liying (1); Zhang, Yuepeng (1); Zhang, Yubao (1); Li, Yanyan (1)
Author affiliation:(1) Mechanical Engineering School, Inner Mongolia Science & Technology University, Baotou; 014010, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:284-288
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Traditional hammer mill generally has the problem that the screening efficiency is lower than the grinding efficiency. In order to improve the screen efficiency of the hammer mill, based on the combination of experiment and numerical simulation method, the influence of the structure parameters of the hammer mill screen and the air flow velocity in the separation device on the screening efficiency was studied, the mechanism of screening was revealed, and the way to improve the screening efficiency of the crusher was explored. According to a type of hammer mill designed by research group, we designed a screening test bench to simulate the air flow field in the separation device of the hammer mill using a blower as the air flow source. In this experiment, 5 kinds of particle sizes through screen were selected, and the influences of 4 factors including the screen hole shape, the screen installation angle, the screen hole arrangement and the air flow velocity on the particle screening efficiency were investigated. In the experiment, 10 kinds of screens were adopted, which were composed of 5 kinds of screen hole shapes and 2 kinds of screen hole arrangements, and there were 11 screen installation angles and 8 kinds of air flow velocity levels selected. The 5 kinds of screen holes were the rectangular hole, the oblong hole, the hexagonal hole, the square hole and the circle hole. The 2 kinds of screen arrangements included "U" type and "T" type arrangement. The experiment showed that the screening efficiency was high and then became low after the air velocity increased; the screen hole shape and screen installation angle had lager effect on the screening efficiency; the arrangement of the screen holes had less effect on the screening efficiency. Also the EDEM-FLUENT software was used to simulate the process of particle screening; the simulation and the experiment results were basically consistent, and the relative error of the two was not more than 4%. Based on this, the research found the optimum combination of the structure parameters and the flow parameters of the screen: when the air flow rate was 6-15 m/s, the screen efficiency of the material was gradually increasing and then decreasing; when the air flow velocity was 6-7 m/s, the phenomenon of material passing through screen was not obvious, mainly because air was not sufficient to drive the movement of particles when the material was under the influence of gravity; when the air flow velocity was more than 7 m/s, the screen efficiency increased, and when air flow speed reached 12.37 m/s, the screening efficiency reached the optimal value, but when the air flow speed continued to increase, the screening efficiency decreased; when the air flow velocity reached 14.21 m/s, the air flow began to negatively impact the particles passing through the screen and the screening efficiency decreased. This was because when the energy of air flow was greater, the particle reached the screen panel with greater speed for the first time, and if they first failed to pass through the screen, they would hit the screen surface to rebound, thereby reducing the secondary screen penetration probability. When the screen installation angle was in the range of 20°-70°, the screening efficiency decreased with the screen installation angle, and the best screen installation angle was 35°-45°; if the screen's opening rate was the same, the screening efficiency of the rectangular hole was the highest among the 5 kinds of screens, and the screening efficiency of circle hole was the lowest of all; the screen hole arrangement had little influence on the screening efficiency. Results suggest that when the air flow velocity was 12.37 m/s, and the screen installation angle was 40°, the rectangular "T" type arrangement had the highest screening efficiency of 0.72-0.74. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:16
Main heading:Air
Controlled terms:Agricultural machinery - Computer software - Flow velocity - Grinding mills - Hammers - Installation - Numerical methods - Optimization - Processing - Source separation - Velocity
Uncontrolled terms:Grinding efficiency - Hammermills - Installation angle - Numerical simulation method - Optimum combination - Screening efficiency - Separation devices - Structure parameter
Classification code:605.2 Small Tools, Unpowered - 631 Fluid Flow - 716.1 Information Theory and Signal Processing - 723 Computer Software, Data Handling and Applications - 804 Chemical Products Generally - 821.1 Agricultural Machinery and Equipment - 913.4 Manufacturing - 921.5 Optimization Techniques - 921.6 Numerical Methods
Numerical data indexing:Percentage 4.00e+00%, Velocity 1.24e+01m/s, Velocity 1.42e+01m/s, Velocity 6.00e+00m/s to 1.50e+01m/s, Velocity 6.00e+00m/s to 7.00e+00m/s, Velocity 7.00e+00m/s
DOI:10.11975/j.issn.1002-6819.2016.22.039
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 40>
Accession number:20164903093310
Title:Emergy analysis on upgraded process systems of bio-oil from pinus sylvestris pyrolysis
Authors:Tai, Yang (1); Huang, Yaji (1); Liu, Changqi (1); Liu, Lingqin (1); Lu, Zhihai (2)
Author affiliation:(1) Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, Southeast University, Nanjing; 210096, China; (2) Tengzhou Yiyuan Coal Gangue Thermal Power Co., Ltd., Tengzhou; 277500, China
Corresponding author:Huang, Yaji(heyyj@seu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:244-250
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Fast pyrolysis of biomass and upgrading techniques for the high chemical value bio-oil production have been investigated widely in recent decades. A variety of upgrading techniques are applied in industrial manufacture process, while the production efficiency and sustainability of those techniques have their own merits and demerits, which emphasizes the importance of the evaluation systems for those techniques. Several evaluation methods, such as energy analysis, exergy analysis, and emergy analysis, have been developed to evaluate the fast pyrolysis of biomass and upgrading techniques. Based on different emergy flows, the methods chosen for the thermodynamic analysis lead to various outcomes. All the input and output energies in an industrial production system are considered in energy analysis, while exergy analysis takes the additional available energy into account. In emergy analysis, all kinds of emergy flows are taken into consideration, including monetary flow, information flow and energy flow. Emergy analysis is derived from the viewpoint that the sun provides the energy for everything on the earth so it is reasonable to convert all kinds of energy to the solar energy. It is so efficient and comprehensive that it has been applied to evaluate the fast pyrolysis of biomass and upgrading techniques. Based on the input-output framework and emergy indices, with the consideration of environment elements, emergy analysis method was applied to comprehensively evaluate two schemes in this paper, achieving upgraded bio-oil from pinus sylvestris by fast pyrolysis and catalytic hydrogenation (Scheme I) and supercritical ethanol upgrading technique (Scheme II), respectively. Meanwhile, the effects of different schemes were compared from three aspects, including production efficiency, environmental support and sustainability. As the results indicated, Scheme II consumed less solar energy and enjoyed higher efficiency when the same amount of fuel was produced. For the input of economic emergy and total emergy, Scheme I were 4.58×10<sup>20</sup>and 4.64×10<sup>20</sup>sej/a while Scheme II were 5.82×10<sup>20</sup>and 5.88×10<sup>20</sup>sej/a respectively, which showed that Scheme I needed less economic emergy input and total emergy input by contrast with Scheme II. For the renewable ratio, Scheme I was 49.57 while Scheme II was 39.12, which showed that renewable emergy input occupied higher percent of the total emergy input in Scheme I. For the environment sustainable index, Scheme I was 0.99 while Scheme II was 0.65, which showed that Scheme I had less stress on the environment and got more support from it. In brief, Scheme I achieves larger renewable ratio, less environment stress, better sustainability and greater environmental support. The optimal direction for both Scheme I and Scheme II is to reduce the emergy input. Scheme I focuses on improving the efficiency of emergy conversion, while Scheme II emphasizes on adjusting the process to reduce the dependency on external support. Compared with the results of energy analysis and exergy analysis, Scheme II needs more total inputs and total energy consumptions, while Scheme I has higher exergy efficiency. Scheme I and Scheme II shared the same emergy yield ratio, which indicated emergy analysis could provide a more comprehensive and deeper evaluation. In sum, theoretical foundations on improving the integrated performance of fast pyrolysis of biomass and upgrading techniques for the bio-oil production are achieved in this paper. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Energy efficiency
Controlled terms:Biofuels - Biomass - Chemical analysis - Cracking (chemical) - Economics - Energy management - Energy utilization - Exergy - Hydrogenation - Investments - Manufacture - Productivity - Pyrolysis - Solar energy - Sustainable development - Thermoanalysis
Uncontrolled terms:Catalytic hydrogenation - Emergy - Environmental supports - Pinus sylvestris - Production efficiency - Theoretical foundations - Thermo dynamic analysis - Upgrading
Classification code:525 Energy Management and Conversion - 537.1 Heat Treatment Processes - 641.1 Thermodynamics - 657.1 Solar Energy and Phenomena - 801 Chemistry - 802.2 Chemical Reactions - 971 Social Sciences
DOI:10.11975/j.issn.1002-6819.2016.22.034
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 41>
Accession number:20164903093303
Title:Method of controllable rectification to shorten voltage recovery time of consequent-pole permanent magnet generator
Authors:Liang, Xuexiu (1); Xu, Jiaqun (2); Jiang, Jie (3); Zhao, Bo (1); Sun, Rongyi (3)
Author affiliation:(1) State Key Laboratory of Soil-Plant-Machine System Technology, Chinese Academy of Agricultural Mechanization Sciences, Beijing; 100083, China; (2) Faculty of Information Technology, Beijing University of Technology, Beijing; 100124, China; (3) Sinomach Intelligence Technology Co., Ltd, Beijing; 100083, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:200-206
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:To realize the function of automotive engine stop-start, it is promising that traditional independent starter and generator in automobile are replaced by the integrated starter/generator (ISG), which contributes to energy conservation and emission reduction. Hybrid excitation starter/generator is a potential selection for the ISG, which has high efficiency over extensive working range, high power density, low maintenance, and high reliability without brushes. The consequent-pole permanent magnet (CPPM) brushless direct-current generator (BLDCG) electromotive force (EMF) is designed to the trapezoidal wave. The trapezoidal wave electromotive force CPPM motor is different from the existing sine wave electromotive force CPPM motor. It has the advantages of high power density, small direct-current (DC) voltage harmonic ripple, only requiring low cost and low resolution Holzer position sensor, simple control and other advantages. The CPPM motor can output stable voltage in the wide speed range. However, the normal brushless DC generator needs to match the complex power converter. Therefore, The CPPM motor is a new type of motor used for electric vehicle. This kind of motor has a good prospect in the application of the ISG of automobile. Generally, the excitation current regulation combined with diode rectification is adopted to meet the requirement of alternator technical specification. However, the large time constant of about 100 ms in excitation winding will cause DC-link voltage drop and lead to abnormal operation of automotive sensitive device, such as engine control unit, and radio. In generating mode, the CPPM BLDCG can be seen as hybrid excitation brushless DC generator. In view of relatively low time constant in armature winding of CPPM BLDCG, it is possible to improve DC-link voltage dynamic performance by regulating armature winding current. This paper takes CPPM BLDCG of 14 V as the research object and aims to shorten the time of voltage recovery. With the method of controlled rectification without increasing hardware cost, the dynamic adjustment process of voltage is analyzed, and the theoretical calculation and experiment of voltage recovery time under 2 different modes of controlled rectifier and diode rectifier are completed. BLDCG CPPM is controlled by the combination of the traditional diode rectifier and the electric field regulation. Its DC voltage recovery time is influenced by the time constant of the excitation winding, which is at the 100 ms level. The dynamic response speed of BLDCG CPPM is maintained at a lower level. A controlled rectification method is proposed to improve DC-link voltage recovery time of CPPM BLDCG. In view of the fast energy storage and release in armature winding, the voltage recovery speed is increased by improving the total EMF of armature winding. The method needs no additional hardware cost. In addition, the method can be extended to hybrid excitation motor with other structures. Dynamic process of CPPM BLDCG with controlled rectification and ultra-capacitor is analyzed by the state-space average method. Theory calculation and experiment on the controlled and diode rectification are separately completed. The results show that the voltage recovery time with the controlled rectification is almost the half of that with the diode rectification. The reason is that the controlled rectifier using BLDCG CPPM armature windings to achieve rapid energy storage and release, can effectively improve the armature winding EMF, and thus can shorten the voltage regulation time. It is of great significance to improve the reliability of the on-board sensitive electronic equipment. Therefore, this kind of controllable rectification method has a good prospect in the automobile ISG application aspect. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Electric machine control
Controlled terms:Automobile electronic equipment - Automobiles - Costs - DC generators - Diodes - Electric fields - Electric generators - Electric rectifiers - Electric windings - Electromotive force - Electronic equipment - Emission control - Energy storage - Engines - Experiments - Hardware - Magnets - Oscillators (electronic) - Permanent magnets - Recovery - Rectifying circuits - Starters - Synchronous generators - Traction motors - Voltage control - Voltage regulators - Winding
Uncontrolled terms:Brushless DC generators - Consequent-pole - Power generator - Rectification - Voltage recovery time
Classification code:451.2 Air Pollution Control - 525.7 Energy Storage - 605 Small Tools and Hardware - 662.1 Automobiles - 662.4 Automobile and Smaller Vehicle Components - 691.2 Materials Handling Methods - 701.1 Electricity: Basic Concepts and Phenomena - 704.1 Electric Components - 705 Electric Generators and Motors - 713.2 Oscillators - 731.2 Control System Applications - 731.3 Specific Variables Control - 732.1 Control Equipment - 801.4.1 Electrochemistry - 901.3 Engineering Research - 911 Cost and Value Engineering; Industrial Economics
Numerical data indexing:Time 1.00e+02m/s, Voltage 1.40e+01V
DOI:10.11975/j.issn.1002-6819.2016.22.027
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 42>
Accession number:20164903093319
Title:Walnut phenolic compounds: Binding with proteins and antioxidant activities
Authors:Su, Shiwei (1); Wang, Ruican (1); Guo, Shuntang (1); Zhang, Chao (2); Zhang, Ting (2); Liang, Ming (2)
Author affiliation:(1) College of Food Science and Nutritional Engineering, China Agricultural University, Beijing; 100083, China; (2) Infinitus China) Company Ltd., Guangzhou; 510665, China
Corresponding author:Guo, Shuntang(shuntang@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:309-314
Language:English
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Walnut (Juglans regia L.) is rich in phenolic compounds (POHs) which show profound antioxidant capacity. But the extraction of POHs could not be completed as they usually interact with walnut proteins. In this study, different amount of urea or NaCl were added to walnut protein solutions in order to analyze the interactions between the POHs and proteins. Results showed that 77.7% total phenolic compounds and 34.6% total condensed tannins (at pH 3.0), 65.4% total phenolic compounds and 59.4% condensed tannins (at pH 8.0) bonding with proteins through various non-covalent bonds, among which hydrophobic bonds were predominant. Besides, the antioxidant activities of POHs were investigated. It showed that the POHs bonding with proteins through ionic bonds could scavenge 5.7% DPPH radical and chelate 5.9% Fe<sup>2+</sup>at pH 3.0 while scavenge 10.9% DPPH radical and chelate 11.5% Fe<sup>2+</sup>at pH 8.0, demonstrating the strongest antioxidant activities. In addition, the efficiency of 70% (v/v) ethanol and 60% (v/v) methanol in extracting POHs and condensed tannins from WPI at pH 3.0 and 8.0 were tested. Results showed the above two commonly used extractants could only slightly promote the extraction of POHs and were not efficient in extracting the POHs with higher antioxidant capacity. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Proteins
Controlled terms:Antioxidants - Bonding - Chelation - Covalent bonds - Extraction - Flavonoids - Iron compounds - Phenols - Tannins - Urea
Uncontrolled terms:Anti-oxidant activities - Antioxidant capacity - Condensed tannins - Dpph radicals - Hydrophobic bonds - Phenolic compounds - Total phenolic compounds - Walnut proteins
Classification code:801.4 Physical Chemistry - 802.2 Chemical Reactions - 802.3 Chemical Operations - 804.1 Organic Compounds
Numerical data indexing:Percentage 1.09e+01%, Percentage 3.46e+01%, Percentage 5.70e+00%, Percentage 5.94e+01%, Percentage 6.00e+01%, Percentage 7.00e+01%, Percentage 7.77e+01%
DOI:10.11975/j.issn.1002-6819.2016.22.043
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.
<RECORD 43>
Accession number:20164903093307
Title:Suitable compactness of corn stover improving characteristics of solid-state anaerobic digestion
Authors:Zhong, Hui (1); Chou, Santao (1); Zhu, Jiying (1)
Author affiliation:(1) School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo; 255000, China
Corresponding author:Zhu, Jiying(zhuying7711@sdut.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:22
Issue date:November 15, 2016
Publication year:2016
Pages:227-232
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:To study the effects of compactness on the performance of solid-state anaerobic digestion (SS-AD), the SS-AD of corn stove was conducted with different total solid (TS) contents. The digestion material with the TS content of 20% was loaded into the reactors at the compactness of 0.56, 0.71 and 0.79 kg/L, and the compactness of the digestion material with the TS content of 25% was 0.43, 0.56 and 0.70 kg/L, respectively. The results showed that with the same TS content, the compaction degree had no significant effect on the peak time of daily methane yields, but the peak value significantly decreased (P<0.05) with the compaction degree increasing. For the reactors with the initial TS of 25%, the peak value of daily methane yield of the reactors with the compactness of 0.70 kg/L decreased by 12.8% and 21.8% compared to that with the compaction degree of 0.56 and 0.43 kg/L, respectively. The variation trends of methane concentration and daily methane yield and cumulated methane yield (based on volatile solid, L/(kg·d)) of the reactors with different compactness of the digestion material had no significant difference. However, if calculating the biogas yield based on the volume of the reactor, the result would be completely different. Both of the peak values of daily methane yield and accumulated methane yield were positively related to the compactness. The effects of compactness on solid state anaerobic digestion process were enhanced with the increase of the initial TS content. With the initial TS content of 20%, the peak values of daily methane yield and accumulated methane yield of the reactors with the compactness of 0.79 kg/L were 0.83 L/(L·d) and 32.48 L/L, respectively, which were 29.2% and 37.1% higher than that of the reactors with the compactness of 0.56 kg/L. When the initial TS content was increased to 25%, the peak values of daily methane yield and accumulated methane yield of the reactors with the compactness of 0.70 kg/L were 0.84 L/(L·d) and 25.08 L/L, respectively, which were 52.7% and 60.2% higher than that of the reactors with the compactness of 0.43 kg/L. For the reactors with the initial TS content of 20%, the physical and chemical properties, such as TS, volatile solid (VS), pH value and total volatile fatty acid (TVFA) concentration of the substrates at top and bottom layer were obviously different during the digestion, while the difference gradually narrowed with the increase of compaction degree of the digestion material. However, the physical and chemical properties of the substrates at top and bottom layer in the reactors with the initial TS content of 25% were similar. This was probably due to the high solids content, which made it difficult to form continuous free flowing mobile phase in the substrate, and then the penetration and diffusion of the intermediates were blocked. The results above indicated that increasing packing density of the substrate with the initial TS content of 20% could improve the mass transfer process of the intermediates. The increase of the compactness made it possible to form a continuous liquid phase in the digestion material, which was beneficial to the degradation of the substrate and diffusion of the intermediates. While for the substrate with the initial TS content of 25%, increasing packing density had no significant effect on mass transfer. In summary, the increase of the compaction degree of the digestion material can maintain the normal process biogas yield of the solid-state anaerobic digestion of corn stover, and also can significantly enhance the volume efficiency of the reactors. © 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Anaerobic digestion
Controlled terms:Biogas - Chemical properties - Compaction - Fatty acids - Fermentation - Mass transfer - Methane - pH - Straw - Substrates - Volatile fatty acids
Uncontrolled terms:Compaction degree - Compactness - Mass transfer process - Methane concentrations - Physical and chemical properties - Solid-state anaerobic digestions - Total volatile fatty acids - Volume efficiency
Classification code:641.3 Mass Transfer - 801 Chemistry - 801.1 Chemistry, General - 804.1 Organic Compounds - 821.5 Agricultural Wastes
Numerical data indexing:Mass_Density 4.30e+02kg/m3, Mass_Density 5.60e+02kg/m3, Mass_Density 7.00e+02kg/m3, Mass_Density 7.90e+02kg/m3, Percentage 1.28e+01%, Percentage 2.00e+01%, Percentage 2.18e+01%, Percentage 2.50e+01%, Percentage 2.92e+01%, Percentage 3.71e+01%, Percentage 5.27e+01%, Percentage 6.02e+01%
DOI:10.11975/j.issn.1002-6819.2016.22.031
Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.