<RECORD 1>
Accession number:20153101103445
Title:Monte-Carlo simulation of yield effect under singular seeding strategy in maize based on Voronoi diagrams
Authors:Han, Zhongzhi (1); Cao, Hongbo (1); Gao, Hongyan (1); Yu, Yan (1); Yang, Jinzhong (1)
Author affiliation:(1) Qingdao Agricultural University, Shandong Provincial Key Laboratory of Dry Farming Techniques, Qingdao, China
Corresponding author:Yang, Jinzhong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:17-21
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Maize precision planting with single seeding that saves labor costs for thinning seedlings is becoming one of the most popular technical innovations in China's maize production. Compared with conventional planting, i.e. multiple seeds per hill to tackle the problem of seedling emergence rate less than 100%, which ensures at least one seedling per hill by planting adequate seeds, what are land patches with missing seedlings under planting one seed per hill like? What variation will occur to maize yields? What seeding strategies should be adopted for high maize yields? These are still open questions. The paper put forward a new computer simulation procedure of planting one seed per hill to plant maize. The procedure consisted of 4 key parts. Firstly, Monte-Carlo simulation of binomial distributions was applied to mimic the number of missing seedlings in cornfields. Secondly, a patch of land with missing plants was partitioned among its surrounding seedlings in the way showed as Voronoi diagrams. Thirdly, for the plant occupying a given area of land, its grain yield was computed using a mathematically identical transformation based on the parabola equation, which was extensively used to relate crop yield to plant density for maize. Lastly, the maize crop yield was evaluated as the sum of individual grain yield per hectare. The simulated results, with seedling emergence rates from 75% to 95%, showed that the number of the patches with missing plants in the field varied with seedling emergence rate following an unimodal curve (R<sup>2</sup>=0.996), with the maximum fleck number of 7.5 per 100 hills at the emergence rate of 82.3%. The patch size decreased with the increasing of seedling emergence rate in a negative exponential function pattern (R<sup>2</sup>=0.994). Planting one seed per hill reduced maize yield by 0.06%-16.78%, and the reduction rate displayed the steady falling trend with the increasing of emergence rate. For single seeding, Strategy II outweighed Strategy I in the crop yield (P<0.03) and the yield stability (R<sup>2</sup>=0.850), the seeding rate for Strategy I was equal to recommended planting density and that for Strategy II was equal to recommended planting density divided by emergence rate. Technical approaches to improve seedling emergence rate were discussed. Our recommendation for single seeding strategy is that, after adopting every mean to promote seedling emergence rate, the seed number sowed should be equal to the target planting density divided by the seedling emergence rate in order that emerged seedlings can reach the optimum planting density. The recommendation will play an important role for spreading the practices in planting one seed per hill in maize production. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:23
Main heading:Seed
Controlled terms:Agricultural machinery - Agriculture - Compensation (personnel) - Computational geometry - Crops - Exponential functions - Grain (agricultural product) - Graphic methods - Intelligent systems - Monte Carlo methods - Wages
Uncontrolled terms:Binomial distribution - Negative exponential functions - Planting one seed per hill - Seedling emergence - Simulation procedures - Transformation based - Voronoi diagrams - Yield
Classification code:723.4 Artificial Intelligence - 723.5 Computer Applications - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 912.4 Personnel - 921 Mathematics - 921.4 Combinatorial Mathematics, Includes Graph Theory, Set Theory - 922.2 Mathematical Statistics
DOI:10.11975/j.issn.1002-6819.2015.13.003
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 2>
Accession number:20153101103463
Title:Direct shear friction test and numerical simulation of soil-soil and root-soil interface of Hedysarum scoparium and Salix psammophila
Authors:Tian, Jia (1); Cao, Bing (1); Ji, Jinnan (2); Zhao, Yuanxiao (1); Li, Caihua (1); Guo, Ting (1)
Author affiliation:(1) Agriculture School of Ningxia University, Yinchuan, China; (2) Key Lab of Soil and Water Conservation and Desertification Combating, Ministry of Education, Beijing Forestry University, Beijing, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:149-156
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Hedysarum scoparium and Salix psammophila have obvious effect on the fixation of mobile and semi-mobile dunes in the Mu Us Desert. In order to explore the friction characteristics between root and soil, 5-year-old Hedysarum scoparium and Salix psammophila roots were measured in the laboratory. The influences of different conditions such as species, soil moisture and vertical load were examined by using direct shear friction tests in the study. The finite element software was used to simulate the process of the laboratory experiments. The results showed that the cohesion stress of the root-soil interface of Hedysarum scoparium and Salix psammophila had a significant difference (P < 0.05). However, there was no significant difference between Hedysarum scoparium root-soil interface and soil-soil interface (P > 0.05). The cohesion stress of the root-soil interface of Salix psammophila and soil-soil interface had a significant difference (P < 0.05). The cohesion stress of the root-soil interface of Hedysarum scoparium ((1.51±0.65) kPa) was higher than that of Salix psammophila ((-0.92±0.50) kPa), and the cohesion stress of soil-soil interface ((3.22±0.55)kPa) was also higher than that of Salix psammophila. The friction angle of the root-soil interface of Hedysarum scoparium had a significant difference with Salix psammophila (P < 0.05) and it also had a significant difference with soil-soil interface (P < 0.05). However, there was no significant difference between Salix psammophila root-soil interface and soil-soil interface (P > 0.05). The friction angle of the root-soil interface of Hedysarum scoparium ((31.00±0.14)°) was higher than that of soil-soil interface ((30.30±0.25)°) and Salix psammophila((30.20±0.17)°). There was a significant difference between the cohesion stress and the friction angle of the root soil interface (P < 0.05) under 2% (dry season) and 22% (rainy season) soil moisture. However, there was no significant difference under 7%-17% soil moisture (P > 0.05). The cohesion stress of 2% soil moisture ((0.0021±0.34) kPa) was lower than that of 22% soil moisture ((3.16±0.57) kPa). The friction angle of 2% soil moisture ((29.80±0.38)°) was lower than that of 22% soil moisture ((30.92±0.59)°). The relationship between vertical load and shear strength of the root-soil interface obeyed the Mohr-Coulomb theory and the constitutive relation was hyperbola. The maximum relative error of the shear strength simulated by the finite element software was 9.54%. The results of the study indicated that the improvement of shear strength of the root-soil composite was not related to the cohesion stress but related to the friction angle. The shear strength of the root-soil interface of Hedysarum scoparium was stronger than that of soil-soil interface and Salix psammophila (P < 0.01). The change of soil moisture had a similar influence on the cohesion stress and the friction angle of the root-soil interface. The capacity of improving shear strength of soil by root reinforcement was significantly affected by the dry and rainy season (P < 0.05). The process of the direct shear friction tests of root-soil and soil-soil interface could be simulated by the finite element model established in the study. The simulation results were consistent with the laboratory tests. The results of this research can serve as a basis for the further studies on the friction characteristics of root-soil interface and root reinforcement. This study also can provide a reference for the selection of windbreak and sand-fixation tree species. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Shear strength
Controlled terms:Adhesion - Finite element method - Friction - Interfaces (materials) - Moisture - Numerical analysis - Pulp manufacture - Reinforcement - Soil mechanics - Soil moisture - Soil structure interactions - Soils - Tribology
Uncontrolled terms:Direct shear - Finite element software - Friction characteristics - Hedysarum scoparium - Laboratory experiments - Maximum relative errors - Roots - Salix psammophila
Classification code:415 Metals, Plastics, Wood and Other Structural Materials - 421 Strength of Building Materials; Mechanical Properties - 422 Strength of Building Materials; Test Equipment and Methods - 483.1 Soils and Soil Mechanics - 483.2 Foundations - 801 Chemistry - 801.4 Physical Chemistry - 811.1.1 Papermaking Processes - 921.6 Numerical Methods - 931 Classical Physics; Quantum Theory; Relativity - 931.1 Mechanics - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2015.13.021
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 3>
Accession number:20153101103470
Title:Design of device for simulating haze-caused radiation changes in open field and its effect
Authors:Wang, Weinan (1); Li, Yabing (1); Sun, Yutong (1); Li, Gang (1); Wang, Lei (1); Shao, Liping (1); Si, Chuanfei (1); Xiong, Yan (1); Luo, Weihong (1)
Author affiliation:(1) College of Agriculture, Nanjing Agricultural University, Nanjing, China
Corresponding author:Luo, Weihong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:199-206
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The decrease of solar radiation and increase of diffuse radiation proportion caused by haze affect crop productivity. To investigate the impacts of changed radiation by haze on the crop growth, a device that simulating haze-caused radiation changes was designed and tested in an open field during 2013 and 2014. Based on air quality index (AQI), haze is classified into three levels: mild, moderate and heavy haze. The changes of solar radiation under each level of haze condition are determined based on the relationship between AQI and radiation conditions. Global radiation decreases by 11%-21%, 22%- 32%, 33%-54% under mild, moderate, heavy haze while corresponding diffuse radiation proportion are 51%-59%, 60%-68%, 69%-87%, respectively. The optical properties (transmittance, scattering and spatial distribution of visible spectrum) of different thickness and layers of PE film used in the device were experimentally tested as covering materials to simulate radiation conditions under the moderate and heavy haze conditions. Based on the solar height and azimuth angles during crop growing season, the minimum plot area was determined as 20 m<sup>2</sup> to secure 4 m<sup>2</sup> shading area in a plot from 10:00 to 14:00. The haze simulator was designed as a cuboid with 5 m (east-west)×4 m (north-south) × 2 m (above the ground) with the cover material installed on top and without obstacle at the 4 sides to allow free air flow and heat exchange. The device was applied and tested in rice paddy field during two rice growing seasons (2013 and 2014). Solar radiation and other microclimate factors were automatically monitored and 30 minutes average values were recorded during the experiments. The results showed that the changes of total radiation and diffuse radiation proportion under different treatments matched the change scopes of solar radiation under moderate and heavy levels of haze. The spatial distribution of visible spectrum under treatment conditions was not significantly different from that under natural haze conditions. The differences of air, water and soil temperature between shading treatments and control were less than ±0.5 in most of the time, and the differences of air humidity between shading treatments and control were 4%-5%. The canopy thermal image showed no significant difference between shading treatment and control at rice heading stage in 2014. These results indicated that the device designed in this study can be used to simulate haze-caused radiation conditions in open field and has the potential to provide effective field experimental means for investigating the effects of haze on crops. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:22
Main heading:Radiation effects
Controlled terms:Air quality - Atmospheric radiation - Climate change - Crops - Cultivation - Humidity control - Optical properties - Radiation - Solar radiation - Spatial distribution
Uncontrolled terms:Canopy microclimate - Diffuse radiation - Field haze simulator in open field - Haze - Visible spectra
Classification code:402 Buildings and Towers - 443.1 Atmospheric Properties - 657.1 Solar Energy and Phenomena - 711 Electromagnetic Waves - 741.1 Light/Optics - 744 Lasers - 821.3 Agricultural Methods - 821.4 Agricultural Products - 921 Mathematics
DOI:10.11975/j.issn.1002-6819.2015.13.028
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 4>
Accession number:20153101103459
Title:Analysis of efficiency of water utilization in canal-system in Hetao irrigation district based on Horton fractal
Authors:Qu, Zhongyi (1); Yang, Xiao (1); Huang, Yongjiang (1); Du, Bin (1); Yang, Junlin (2)
Author affiliation:(1) Water Conservancy and Civil Engineering College, Inner Mongolia Agricultural University, Hohhot, China; (2) Hetao Irrigation District Management Bureau of Inner Mongolia, Bayannur, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:120-127
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Efficiency of water utilization in large irrigation districts and water-saving potential can reflect degree of water resources utilization and is an important evaluation index of national economic development. It is unknown about effects of canal-system framework on water utilization efficiency in canal-system. In this study, we assessed the relationship between canal-system framework and water utilization efficiency in Hetao Irrigation District, China. The Hetao Irrigation District was divided into Wulanbuhe, Jiefangzha, Yongji, Yichang, and Wulate sub-irrigation districts. The canal-system of Hetao Irrigation district had complex structure with one general canal, 16 trunk canals, 48 sub-main canals, and 57 000 of branch, lateral, field, and sublateral canals. The general, trunk, sub-main, branch, lateral, field and sublateral canals were graded into the first, second, …, and seventh levels. The information on irrigation area, amount, and water use efficiency of each sub-irrigation district in 2012 was collected. Canal-system framework was described by Horton law. The fractal dimension of canal system was calculated based on branch ratio and length ratio of canals. Relationships between fractal dimensions, irrigation amount, efficiencies of water utilization, and irrigation area were evaluated. Then, the proportion of water-saving was calculated. The results showed that the logarithms of canal numbers and length had good linear relationships with canal levels (R<sup>2</sup>>0.9), indicating the estimation of fractal dimensions was highly reliable. Fractal dimensions in sub-irrigation districts of Hetao Irrigation District were 1.14 for Wulanbuhe, 1.86 for Jiefangzha, 2.21 for Yongji, 1.80 for Yichang, 1.99 for Wulate and 1.88 for Hetao. The fractal dimensions were similar for all sub-irrigation districts because the branch and length ratios were similar. In general, branch ratio of canal-systems was too high in Hetao Irrigation District and should be reduced. The relationship among efficiency of water utilization in canal-system, fractal dimension, planting area and irrigation amount was in quadratic function. Based on these relationships, a multivariate quadratic function was fitted with small residues and relative errors smaller than 0.8%. The potential of canal-systems to increase water use efficiencies was 19.01% for Wulanbuhe, 28.80% for Jiefangzha, 32.70% for Yongji, 27.07% for Yichang, and 30.70% for Wulate. It also estimated that the canal-system water-saving development speed averaged 27.19% in Hetao Irrigation District, which was smaller than 28.06% achieved by lining method when lining rate is assumed to be 100% reported by previous studies. However, both lining method and structure optimization method were reliable methods for canal-system plan in irrigation district. Therefore, it is viable to apply Horton Law to canal-system in large irrigation districts. The results here provide valuble information for planning and water-saving reconstruction of irrigation districts. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:43
Main heading:Canals
Controlled terms:Efficiency - Fractal dimension - Fractals - Hydraulic structures - Irrigation - Irrigation canals - Linings - Structural optimization - Water conservation - Water management - Water resources - Zoning
Uncontrolled terms:Canal systems - Canales - Hetao irrigation districts - Horton law - Water - savings
Classification code:403.2 Regional Planning and Development - 407.2 Waterways - 441 Dams and Reservoirs; Hydro Development - 444 Water Resources - 611 Hydroelectric and Tidal Power Plants - 821.3 Agricultural Methods - 913.1 Production Engineering - 921 Mathematics - 921.5 Optimization Techniques - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2015.13.017
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 5>
Accession number:20153101103451
Title:Acoustic performance analysis of micro-perforated muffler in vehicle with uniformly grazing flow
Authors:Zuo, Shuguang (1); Zhang, Jun (1); Wu, Xudong (1); Long, Guo (1); Xiang, Longyang (1); Liu, Jingfang (1)
Author affiliation:(1) Clean Energy Automotive Engineering Center, Tongji University, Shanghai, China
Corresponding author:Wu, Xudong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:60-67
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Transmission loss is a key factor to evaluate the performance of micro-perforated mufflers. In actual application, the mufflers are always applied in the air flow circumstance which would change the acoustic and aerodynamic performance of micro-perforated mufflers. So it is necessary to study the effect on acoustic properties caused by the flow. In this article, the uniform flow is taken into account, which has influence on acoustic impedance of the micro-perforated panel and the sound propagation in the center tube.The theory that how normal incident flow and grazing flow affect the sound propagation is discussed. When it comes to the circular micro-perforated duct mufflers, the grazing flow plays a much more important role in the sound propagation than the normal incident flow. The reason is that only little normal incident flow could pass through the holes to flow into the expansion chamber. The authors establish the one-dimension transmission loss (TL) model of micro-perforated mufflers with uniformly grazing flow. The new model is verified by the experimental result. In the comparison with the original TL model without taking the flow into account, the TL curves calculated by the new model are consistent with the experimental curves, and the relative error ratio drasticallydecreases to 15% from 27.3%. So the new model we established in this article is more accurate. Furthermore, we analyzehow structural parameters exert impact on the acoustic performance of micro-perforated mufflers with uniformly grazing flow based on this model. When the direction of the grazing flow is the same with that of sound propagation, with the grazing flow speed increasing, the TL increases slightly in the low-frequency domain. However, the acoustic performance of the micro-perforated mufflers would degenerate a lot in the medium-to-high frequency domain.The research reveals that the influence caused by the main external size parameters of micro-perforated mufflers with uniformly grazing flow is almost the same with that without flow. As for the perforated parameters, they make a big difference on acoustic performance without uniformly grazing flow, which is different from that with uniformly grazing flow.The amplitude of TL will increase as the diameter of perforation and the thickness of perforated walls increase. And the different perforation ration will change the resonant frequency of the micro-perforated mufflers, furthermore, it also will make a big difference on the bandwidth of noise elimination. But the difference with the uniformly grazing flow is much less than that without flow.Changing the perforation parameters in the normal range, the difference of TL without flow will drastically reach 18 dB. In conclusion, designing micro-perforated mufflers with multi-cavities in the uniformly grazing flow circumstance only needs to determine the size of external structure according to the TL calculated under the condition which is without flow. As for the perforation parameters, we can set the values by experience because of their slight influence on the TL.The theoretical model in this paper can predict the transmission loss more accurately. And the study of the influence on acoustic performance caused by changing structural parameters can provide the reference to design a muffler according to the target frequency. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Automobile mufflers
Controlled terms:Acoustic impedance - Acoustic properties - Acoustic wave propagation - Amphibious vehicles - Frequency domain analysis - Models - Natural frequencies - Wave transmission
Uncontrolled terms:Acoustic performance - Aero-dynamic performance - Grazing flows - Micro-perforated - Micro-perforated panels - Structural parameter - Theoretical modeling - Transmission loss
Classification code:663.2 Heavy Duty Motor Vehicle Components - 674.1 Small Marine Craft - 711 Electromagnetic Waves - 711.1 Electromagnetic Waves in Different Media - 731.1 Control Systems - 751.1 Acoustic Waves - 751.2 Acoustic Properties of Materials - 902.1 Engineering Graphics
DOI:10.11975/j.issn.1002-6819.2015.13.009
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 6>
Accession number:20153101103468
Title:Identification of pod beak and constriction and quantitative analysis of DUS traits based on Freeman Chain Code
Authors:Deng, Limiao (1); Du, Hongwei (2); Han, Zhongzhi (1)
Author affiliation:(1) School of Science and Information, Qingdao Agricultural University, Qingdao, China; (2) School of Mechanical and Electrical Engineering, Qingdao Agricultural University, Qingdao, China
Corresponding author:Han, Zhongzhi
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:186-192
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Pod beak and constriction play an important role in the cultivar identification of peanut. However, little research has been done in the identification of pod beak and constriction based on image processing. To identify pod beak and constriction automatically and evaluate the feasibility of image process techniques for quantifying peanut DUS traits, the identification of pod beak and constriction and quantitative analysis of DUS traits based on Freeman Chain Code were proposed. Twelve peanut varieties from Heibei and Shandong provinces (Rizhao, Weifang, Qingdao, Yantai city) were used and 50 peanut pods were randomly selected from each variety. A scanner was used to capture images of the peanut samples. Preprocessing including image segmentation, graying, enhancement and binarization were conducted to the peanut images. To make the proposed method robust to rotational change, a rotational operation was performed to make the pod in vertical direction. Then, image edge was extracted from the binary image and eight-direction freeman chain code was applied to code the edge. Approximate curvature method and local maximum method were used to detect inner corner points and exclude the pseudo corner points. Local maximum method was used to remove the adjacent corner points and keep the point with the largest curvature within a neighborhood. Pod beak and constriction were identified by their locations. Meanwhile, some other corner detection methods, such as Moravec, Harris and SUSAN algorithms, were used for comparison with the proposed method here. Finally, 3 DUS testing traits were extracted and quantified using image process techniques. Degree of pod constriction was qualified by the location of pod constriction and graded by the value of the pod constriction degree. Distinctness degree of pod beak was qualified by the curvature where the pod beak was located. The length of pod was qualified by the length of its minimal outer rectangle. To evaluate the proposed method, 600 peanut samples were selected for identification of pod beak and constriction. Results showed that the accuracy of pod beak and constriction identification based on Freeman Chain Code were 93.1% and 95.5%, respectively. The false alarm rates of pod beak and constriction identification were 7.3% and 5.8%, respectively. Comparably, the Freeman Chain Code method was better than the other three with the accuracy for pod beak identification of 53.4% with Moravec, 85.5% with Harris and 83.4% with SUSAN, and the pod constriction identification accuracy of 48.5% with Moravec, 82.3% with Harris, and 84.2% with SUSAN. Meanwhile, the processing speed was also higher (468 ms) than the others (1436, 738, 567 ms). Based on quantified DUS testing traits using Freeman Chain Code, the peanut grading accuracy could achieve 92.4% for 524 samples. The grading accuracy of the distinctness degree of pod beak was 91.7% for 436 samples. The relative error of pod length measurement was 5.8%. In sum, the Freeman Chain Code method is effective in image recognition of peanut beak and constriction and also for quantification of peanut DUS trait. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Image processing
Controlled terms:Algorithms - Chains - Codes (symbols) - Edge detection - Grading - Image coding - Image recognition - Image segmentation - Oilseeds
Uncontrolled terms:Cultivar identification - Freeman chain code - Freeman coding - Identification accuracy - Length measurement - Peanut pods - Process techniques - Vertical direction
Classification code:602.1 Mechanical Drives - 716 Telecommunication; Radar, Radio and Television - 723 Computer Software, Data Handling and Applications - 723.2 Data Processing and Image Processing - 821.4 Agricultural Products - 913.3 Quality Assurance and Control - 921 Mathematics
DOI:10.11975/j.issn.1002-6819.2015.13.026
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 7>
Accession number:20153101103443
Title:Feasibility analysis of replacing full factorial design with Taguchi method in mini-plot soil erosion experiments
Authors:Zhang, Fengbao (1); Yang, Mingyi (1); Li, Zhanbin (1)
Author affiliation:(1) State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, China; (2) Institute of Soil and Water Conservation, CAS and MWR, Yangling, China; (3) Institute of Water Resources and Hydro-electric Engineering, Xi'an University of Technology, Xi'an, China
Corresponding author:Yang, Mingyi
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:1-9
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:During plot experiments with full factorial designs in order to understand the effects of factors such as soil type, slope gradient, slope length, rainfall characteristics, hydraulic factors, vegetation cover and human activities on soil erosion processes, the number of tests increases with the increasing number of factors and their levels, often leading to time, cost and labor consuming. Taguchi method has been evidenced as a simple, economical and efficient experiment design method in fields of engineering, environment and others, but not in soil erosion studies. This study investigated the feasibility of using Taguchi design method in studies on soil erosion under different conditions. To achieve this objective, a published dataset of mini-plot soil erosion by Meyer and Harmon in 1989 was used. This dataset included four factors and four levels of soil type (Brooksville, Dubbs, Atwood and Loring), slope gradient (5%, 10%, 20 and 30%), slope length (0.15, 0.3, 0.45 and 0.6 m) and rainfall intensity (13.6-14, 26.4-27, 74.3-76.3 and 112-115 mm/h). Results from Taguchi method, orthogonal design and full factorial design were compared. For comparison, the results from full factorial design were considered as measured values. Results showed that the test numbers used for Taguchi method/orthogonal design were only 6.3% of that for full factorial design, but there was no significant difference in mean of runoff and erosion rate between Taguchi method and the other methods. The maximum, minimum and variation coefficient and standard deviation for the erosion and runoff rates between the methods were slightly different. The main effect of each factor on the erosion and runoff rates obtained from Taguchi method followed the same trends with those obtained from full factorial design, but different from the orthogonal design sometimes. The three methods all could identify that rain intensity was the main contributor to slope erosion. However, the contribution rates from the three methods were different with higher value from Taguchi method than the others, probably because the Taguchi method could effectively reduce contribution of uncontrollable factors such as noise. In general, the contribution of each factor to the variation of erosion and runoff rate from Taguchi method was much closer to full factorial design method. The optimum condition obtained from Taguchi method to produce the maximum erosion was the same with that from the measured results. The determination coefficients (R<sup>2</sup>) of the predicted values by Taguchi design and the measured values were 0.993 (P < 0.001, N=254) and 0.929 (P < 0.001, N=254) for the runoff and erosion rates, respectively. The Nash-Sutcliffe Efficiency index between the predicted values by Taguchi design and measured values were 0.992 and 0.841 for the runoff and erosion rates, respectively. All above results indicate that the Taguchi method can replace full factorial designs in mini-plot erosion studies to produce the credible results and decrease the test numbers and the costs. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:23
Main heading:Design
Controlled terms:Erosion - Rain - Runoff - Soils - Taguchi methods
Uncontrolled terms:Determination coefficients - Feasibility analysis - Full factorial design - Mini-plot - Optimum conditions - Rainfall characteristics - Uncontrollable factors - Variation coefficient
Classification code:407 Maritime and Port Structures; Rivers and Other Waterways - 408 Structural Design - 443.3 Precipitation - 444.1 Surface Water - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 913.3 Quality Assurance and Control
DOI:10.11975/j.issn.1002-6819.2015.13.001
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 8>
Accession number:20153101103465
Title:Hillslope morphology evolution in loess watershed model based on complex network
Authors:Tian, Jian (1); Tang, Guo'an (1); Zhao, Mingwei (3)
Author affiliation:(1) Key Laboratory of Virtual Geographic Environment, Ministry of Education, Nanjing Normal University, Nanjing, China; (2) School of Resources and Environment Engineering, Hefei University of Technology, Hefei, China; (3) State Key Laboratory of Resources and Environment Information System, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing, China
Corresponding author:Tang, Guo'an
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:164-170
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The evolution of slope is the result of slope process and one of the issues of geomorphic system for drainage basin. In the present study, a complex network method was adopted to build up the spatial structure of slope system in order to explore the evolution rules of slope system. Data were high-resolution digital elevation model (DEM) of 9 stages, which were gathered by close range photogrammetry during different stages of the runoff experiment. Slope form was classified into 7 slope types, i.e. flat slope, steep slope, double-straight slope, double-concave slope, double-convex slope, convex-straight slope and concave-straight slope. Slope unit was further segmented using object-based image analysis method with the terrain factors including slope, plan curvature and profile curvature. Scale parameter of slope segmentation was set to 10 units depending on change rate of local variance on segmentation model. The classification map of slope forms was completed based on the classification rules of slope unit. Slope networks referred to objects composed of slope units and connection between these units. Each node represented slope form which was the terrain condition of sediment transfer. Edges illustrated the spatial link relations between slope forms. Nine slope networks were established in 9 stages, and average degree, degree-relation and structure entropy were taken as network indices to measure network characteristics. Results showed that the degree distribution of slope network fitted power law, so it was a kind of scale-free network. Steep slope was one key node which controlled the structure of network. New nodes preferred to connect with the node with high average degree under gravity erosion, therefore, double-straight slope was apt to transform into steep slope. Moreover, slope network is a disassortative network as minus assortative factor. Slope form with low degree was easily distributed around node with high degree. In the evolution of slope system, new slope forms constantly emerged and network structure entropy tended to grow large and then stabilize under the effect of rainfall erosion. Specifically average degree and structure entropy of network were rapidly enlarged with strong rainfall in the 2nd stage. According to the change rate of network structure entropy, the evolution of network could be divided into 3 periods, which were sprouting development and mature period. Average degree of network showed periodic change because the function of each slope form had changed in different stages. Double-straight slope as initial slope had high average degree, then its average degree continuously reduced with erosion, and the number of its node constantly increased. Average degree of steep slope reached the peak in the network of the 5th stage after it consistently increased since the 2nd stage, and then it slightly dropped. During the evolution of the 2nd-3rd and 4th-5th network, sediment discharge clearly expanded under similar rainfall condition. Steep slope was one important phase for sediment transfer, and the sediment discharge of slope system was influenced by its average degree. However, the average degree of double-convex slope, convex-straight slope and concave-straight slope had a little change during the network evolution. Due to the effect of headward erosion, the average degree of double-concave slope rose gradually after the network of the 5th stage. Some steep slopes were likely converted into double-concave slope under deposition, which decreased sediment discharge of slope system. Rainfall intensity was an important factor of network structure entropy. When average rainfall intensity was beyond 1.5 mm/min, the change rates of structure entropy of the network of the 2nd, 3rd, 5th and 8th stage were high and the network structures had changed dramatically. The reason was that splash and gravity erosion were leading driving forces for slope evolution. On the contrary, its structure entropy slightly dropped in the case of the low rainfall intensity. At the point, deposition process played an active role in slope evolution. In short, slope washing, incision, combination and deposition were slope processes for shaping the structure of slope system. It is demonstrated that spatial complex network approach is a novel framework for exploring the evolution of geomorphic system. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Complex networks
Controlled terms:Catchments - Deposition - Entropy - Erosion - Geomorphology - Landforms - Rain - Sediments - Surveying - Watersheds
Uncontrolled terms:Classification rules - Close range photogrammetry - Degree distributions - Digital elevation model - Hillslopes - Network characteristics - Network structure entropies - Object based image analysis
Classification code:405.3 Surveying - 443.3 Precipitation - 444 Water Resources - 444.1 Surface Water - 481.1 Geology - 481.1.1 Geomorphology - 483 Soil Mechanics and Foundations - 641.1 Thermodynamics - 722 Computer Systems and Equipment - 813.1 Coating Techniques
DOI:10.11975/j.issn.1002-6819.2015.13.023
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 9>
Accession number:20153101103482
Title:Steam explosion increasing water soluble pentosan content of wheat bran and its thermogravimetric analysis
Authors:He, Yonghui (1); Wang, Qinghua (1); Huang, Huili (1); Wang, Yanrong (1); Liu, Xingyou (1)
Author affiliation:(1) Department of Animal Science, Henan Institute of Science and Technology, Xinxiang, China; (2) Intelligent Cleaner Production of Livestock and Poultry in Henan Province Engineering Laboratory, Xinxiang, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:286-291
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The experiment was conducted to investigate the effects of steam explosion on water soluble pentosans mass fraction of wheat bran. The common commercial wheat bran was exploded by steam under the conditions as follows: the ratio of water to material was 20%, 30% and 50%, steam retention time was 30, 60 and 120 s per ratio of water to material, and steam pressure was kept at 2.0 MPa. Mass fractions of water soluble pentosans, total pentosan, neutral detergent fiber, acid detergent fiber and hemicellulose, and thermogravimetric curves were analyzed. The results showed that steam explosion could significantly increase the mass fraction of water soluble pentosans in wheat bran (P<0.05). Under the same steam pressure, water soluble pentosan mass fraction of the treatments through steam explosion could be increased with the lengthening of steam retention time (P<0.05), water soluble pentosan mass fraction under 60 s steam retention time could be increased by 9.0 times (P<0.05), and that under 120 s retention time could be increased by 10.1 times (P<0.05) compared with untreated wheat bran. Compared with untreated bran, steam explosion increased water soluble pentosans mass fraction at different degree with the increase of ratio of water to material (P<0.05), which could be increased by 9.4 times (P<0.05) at 30% ratio of water to material and by 6.5 times at 50% ratio of water to material (P>0.05). The mass fraction of total pentosans could be significantly decreased in wheat bran by steam explosion (P<0.05), and reduced by 62% (P<0.05) under the conditions of 20% water material ratio, 2.0 MPa steam pressure and 120 s steam retention time compared with untreated wheat bran. Considering the extraction efficiency and energy consumption, the better steam explosion conditions for water soluble pentosans were 30% ratio of water to material and steam processing for 60 s when steam pressure was kept at 2.0 MPa, and under these conditions mass fraction of water soluble pentosans could be increased by 10.8 times (from 1.3% to 13.9%), neutral detergent fiber could be decreased by 17.2% (P<0.05), hemicellulose decreased by 26.7% (P<0.05), activation energy of hemicellulose pyrolysis process increased by 21.5%, initial and end temperature were postponed by 19-30, temperature corresponding to maximum weight loss rate took forward by 13 and maximum weight loss rate reduced by 43%. This study demonstrates that steam explosion can significantly improve the mass fraction of functional active polysaccharides (water soluble pentosan) in wheat bran, which is helpful for deep processing and utilization of wheat bran. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:22
Main heading:Steam
Controlled terms:Activation energy - Cellulose - Energy utilization - Explosions - Polysaccharides - Thermogravimetric analysis
Uncontrolled terms:Acid detergent fiber - Arabinoxylans - Extraction efficiencies - Neutral detergent fiber - Pentosan - Thermogravimetric curve - Weight loss rates - Wheat bran
Classification code:502.1 Mine and Quarry Operations - 525.3 Energy Utilization - 614 Steam Power Plants - 801 Chemistry - 801.4 Physical Chemistry - 804.1 Organic Compounds - 815.1.1 Organic Polymers
DOI:10.11975/j.issn.1002-6819.2015.13.040
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 10>
Accession number:20153101103464
Title:Impacts of freeze-thaw cycles on runoff and sediment yield of slope land
Authors:Wei, Xia (1); Li, Xungui (1); Huang, Chihua (2)
Author affiliation:(1) College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, China; (2) Agronomy Dep., Purdue Univ., USDA-ARS National Soil Erosion Research Lab., 275 S Russell St, West Lafayette; IN, United States
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:157-163
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Although freeze-thaw cycles can alter soil physical properties and microbial activity, their overall impact on soil functioning remains unclear. Soil experiencing freeze-thaw is more vulnerable to become erosion material source of erosion, thereby increasing the severity of a variety of soil erosion. In order to reveal the influence of freeze-thaw effects on soil erosion by water, in this paper we quantitatively tested the hypothesis that soil freeze-thaw processes significantly increase the potential for soil erosion by water during rainfall-runoff events. The freeze-thaw cycles detection system and simulated rainfall equipment were used for the experiment. Control test was designed as an unfrozen soil with air-dried. The experimental design involved four simulated rainfall intensities (25, 50, 75 and 100 mm/h), two freeze-thaw cycles (FTC=3 and 6) and two kinds of soil moisture mass fraction (10% and 20%) on four 0.5-m-long, 0.2-m-wide, and 0.1-m-deep soil boxes set at 5% slope. Experiments were conducted at the USDA-ARS National Soil Erosion Research Lab. Surface soil (0-10 cm) materials from a Crosby-Miami complex alfisol with 20% clay, 66% silt and 14% sand from the Purdue Animal Science Research and Education Center in West Lafayette, Indiana. The test soil was air-dried, crushed and passed through an 8-mm sieve, and then experienced the designed freeze-thaw pattern. A 100-min continuous rainstorm was applied. The storm consisted of four intensity sequences: 50 mm/h for 60 min, 25 mm/h for 20 min, 75 mm/h for 10 min and 100 mm/h for 10 min. Runoff samples were collected in 1-L HDPE bottles every 5 min during the two lower intensity rains and every 3 min during the two higher intensity rains. Time to fill the runoff bottle was recorded. After each run, the sample bottles were weighed immediately to obtain the runoff rate. Approximately 5 mL of saturated alum solution was added to the sample bottles to flocculate the suspended sediment. After settling overnight, the excess water was poured off the bottles. The bottles were placed in the oven set at 105 °C for at least 24 h or until the sediments were dried. Dry weights were then taken to calculate the sediment delivery rate and concentration. The results showed that all kinds of experimental treatments could increase runoff and sediment yield intensity under the same rainfall intensity compared with the control test, and sediment yield intensity increased significantly greater than runoff generation intensity. Runoff generation intensity and sediment yield intensity increased with increasing soil moisture mass fraction when freeze-thaw cycles and rainfall intensities were same. The variation of runoff generation intensity and sediment yield intensity with freeze-thaw cycles were relatively complex. Runoff generation intensity and sediment yield intensity increased with increasing freeze-thaw cycles when soil moisture mass fraction was 10%. When soil moisture mass fraction was 20%, runoff generation intensity and sediment yield intensity decreased with increasing freeze-thaw cycles. When soil moisture mass fraction was 10%, and the freeze-thaw cycles both were 3 and 6, total runoff generation amount increase were 3.52% and 4.71%, respectively, total sediment yield amount increase were 6.13% and 16.95%, respectively. When soil moisture mass fraction was 20%, and the freezing and thawing cycles both were 3 and 6, total runoff generation amount increase percentage were 10.24% and 5.01%, respectively, total sediment yield amount increase were 81.99% and 53.07%, respectively. Under the same rainfall intensity, impact of soil moisture mass fraction on runoff generation intensity and sediment yield intensity was big, and the impact of freeze-thaw cycles on runoff generation intensity and sediment yield intensity was relatively small. This paper can provide an insight for the mechanism of freeze-thaw erosion. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Soil testing
Controlled terms:Bottles - Erosion - Forestry - Freezing - Moisture - Rain - Runoff - Sediments - Soil mechanics - Soil moisture - Soil structure interactions - Soils - Storms - Suspended sediments - Thawing
Uncontrolled terms:Freeze-thaw - Freezing and thawing cycle - Microbial activities - Rainfall-runoff events - Runoff and sediment yields - Sediment yields - Simulated rainfall - Soil physical property
Classification code:443.1 Atmospheric Properties - 443.3 Precipitation - 444.1 Surface Water - 483 Soil Mechanics and Foundations - 694.2 Packaging Materials - 821.0 Woodlands and Forestry - 822.2 Food Processing Operations
DOI:10.11975/j.issn.1002-6819.2015.13.022
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 11>
Accession number:20153101103458
Title:Flow state characteristics and fractal model parameters determination of quartz sand filter layer used in micro-irrigation
Authors:Li, Jinghai (1); Liu, Qingxia (3); Huang, Xiuqiao (1); Zhai, Guoliang (1); Han, Qibiao (1)
Author affiliation:(1) Farmland Irrigation Research Institute, Chinese Academy of Agricultural Sciences, Key Laboratory of Water-saving Agriculture in Henan Province, Xinxiang, China; (2) Water Resources Management Committee Office of Anyang City, Anyang, China; (3) Anyang Institute of Technology School of Civil and Architectural Engineering, Anyang, China
Corresponding author:Huang, Xiuqiao
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:113-119
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Quartz sand, one kind of porous media, is commonly used in micro-irrigation filter. Selecting optimal filtration speed and pressure drop of clean are important for design and operation of filters. In this study, fluid equation for porous media and fractal models were proposed to determine pressure drop of quartz sand layer. In order to facilitate flow zone division, we introduced dimensionless pressure drop into the original fluid equation of porous media. In this way, the empirical coefficients in fluid equation became meaningful. The dimensionless pressure drop is a linear function of Reynolds number, the changes in function curves indicates the changes in flow zones. Based on the dimensionless equation the flow pattern zone could be divided in combination with filtration tests. On the other hand, in the fractal model, the fractal dimensions of the curve and cross section were undetermined parameters. Their values could be determined by the empirical coefficient by comparing the fluid equation with fractal models. The method was demonstrated by a laboratory experiment conducted in Farmland Irrigation Research Institute, Chinese Academy of Agricultural Sciences, Xinjiang, China in 2014. 3 kinds of quartz sand filter layer with different particle sizes were selected based on commonly used sizes in Xinjiang including equivalent sizes of 1.06, 1.2 and 1.5 mm. The sandy layer had a depth of 400 mm and porosity of 0.44. The flow characteristic of irrigation water in micro-irrigation filter with quartz sand was first analyzed and then the empirical coefficient of turbulent flow region was fitted by the experimental data. The parameters of the fractal model were determined, and the expression of fractal model of turbulent flow region was obtained. Using the values of fractal dimension of the curve and cross section in turbulent flow region, the fractal dimensions of curve and cross section in Forchheimer flow region was determined. And the expression of fractal model of Forchheimer flow region was obtained. Finally, the best filtration rate and clean pressure drop were estimated. Results showed that: 1) The Reynold numbers were 2 and 7.3 for size of 1.06 mm, 2 and 10 for size of 1.2 mm, 2 and 16.3 for size of 1.5 mm when Forchheimer zone changed into Turbulent zone. There was a linear relationship between sand size and Reynold numbers. Based on the relationship, the pressure drop could be well estimated with maximum relative error of 5.84%. In the Forchheimer flow region, the pressure drop was also estimated well with maximum relative error of 8.92%. According to the variation of fractal dimension of the curve in Forchheimer flow region, the filter layer could be considered as in a mature stage. The best filtration speed of the filtration layers with equivalent sizes of 1.06, 1.2, and 1.5 mm were 0.02, 0.024 and 0.027 m/s, the best cleaning pressure drops of the 3 filtration layers were 6 045, 9 660, and 14 500 Pa. The research provided valuble information for design, operation and optimization of sand filter in micro irrigation. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:17
Main heading:Fractal dimension
Controlled terms:Drops - Flow patterns - Fractals - Irrigation - Porous materials - Pressure drop - Quartz - Reynolds number - Sand - Turbulent flow
Uncontrolled terms:Design and operations - Different particle sizes - Empirical coefficients - Flow charac-teristics - Laboratory experiments - Linear relationships - Maximum relative errors - Quartz sand
Classification code:443.1 Atmospheric Properties - 482.2 Minerals - 505 Mines and Mining, Nonmetallic - 631.1 Fluid Flow, General - 821.3 Agricultural Methods - 921 Mathematics - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2015.13.016
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 12>
Accession number:20153101103481
Title:Heat transfer and flow performance of indirect heat exchanger by mixed ice water based on natural cold resource
Authors:Zhou, Fujun (1); Pan, Xiaoli (1); Wang, Wenming (1)
Author affiliation:(1) Engineering College of Northeast Agricultural University, Harbin, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:281-285
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:According to the climatic characteristics of long cold winter days in the northern area, the storage of natural cold resources from winter are used for cooling in summer to achieve the goals of conserving energy and reducing carbon emission. To address the issues with regard to controlling the temperature and humidity of environment as well as the usage time of cold resources are short when natural cold resources are used for the storage and preservation of agricultural product through blowing the natural air into the ice storage directly, the ice-water mixture was used as the heat exchange medium and air quality was improved by means of indirect heat exchanger with inner loop cooling. The process route of freezing storage-release cold energy by mixing ice and water-exchange heat indirectly-temperature and humidity independently was proposed in this study. The laboratory used for the experiment was a closed storehouse with a size of 2 m × 2 m × 2 m. The ice water at 0.5 as coolant flowed from top to bottom in the finned tube heat exchanger by use of a water pump. The hot air of environment crossed finned tube under the action of the fan, then the water temperature rose when the cold water flowed through the copper tube wall to absorb heat of the tube outer surface and the fin surface. The cooling air was blown into the storage, the mixture of cooling air and fresh outdoor air exchanged heat in heat exchanger. The measuring element used in the experiment can be connected with the computer, and data acquisition using RMA411 remote input capture module, which can be carried out in 16 channels of analog data acquisition. The data output adopted the distal RM4024 analog output module, which can realize the output of four voltage signals, achieving real time communication between the host computer and data acquisition and output module, through the RS485 serial port. Temperature and humidity acquisition adopted Pt100 temperature sensor and humidity sensor series, respectively. The instrument used in the test was corrected precisely prior to the experiment in order to meet the test requirements. The average value of the air flow was determined by the measurement of the five points of heat exchanger outlet section. The pump flow rate and air flow rate were adjusted by frequency converter. The values of CFD were similar to the value of experiments, and the error was less than 15%. Then the results of the experiments were used to validate the simulation model. The experiment showed that the head wind velocity had a greater influence on the performance of heat exchanger. The heat transfer coefficient and the pressure drop increased by 133% and 428%, respectively with the increase of the head wind velocity. However the increasing trend of heat transfer coefficient became slow as the increasing of wind speed. When the head wind velocity was within the scope of 1.5 to 3.5 m/s, the average field synergy angles increased by 12% and synergistic degree decreased. When the wind speed reached 3.5 m/s, the field synergy angles hardly changed with wind speed. The scope of the best head wind velocity was between 2.5-3 m/s. The air inlet direction has significant impact on air distribution in the heat exchanger. The air inlet direction could affect the heat transfer performance because too high or too low would produce eddy current and the uneven distribution of air flow. The results of the uniform wall temperature numerical simulation had a deviation with the experiments. The cooling capacity increased by 70.6% when the air inlet direction increased from -45 to 30. The heat exchanger had a better performance when the air inlet direction was 30. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:20
Main heading:Heat exchangers
Controlled terms:Agricultural products - Air - Air intakes - Air quality - Carbon - Cold storage - Computational fluid dynamics - Computer simulation - Data acquisition - Digital storage - Eddy current testing - Fins (heat exchange) - Heat transfer - Heat transfer coefficients - Humidity control - Ice - Mixtures - Numerical models - Tubes (components) - Velocity - Water resources - Wind
Uncontrolled terms:Field coordination - Finned tube heat exchangers - Flat fin - Heat transfer performance - Natural cold resources - Temperature and humidities - Temperature and humidity acquisitions - Uniform wall temperatures
Classification code:402 Buildings and Towers - 443 Meteorology - 443.1 Atmospheric Properties - 444 Water Resources - 616.1 Heat Exchange Equipment and Components - 631.1 Fluid Flow, General - 641.2 Heat Transfer - 694.4 Storage - 701.1 Electricity: Basic Concepts and Phenomena - 722.1 Data Storage, Equipment and Techniques - 723.2 Data Processing and Image Processing - 723.5 Computer Applications - 802.3 Chemical Operations - 804 Chemical Products Generally - 821.4 Agricultural Products - 921 Mathematics - 931.1 Mechanics
DOI:10.11975/j.issn.1002-6819.2015.13.039
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 13>
Accession number:20153101103474
Title:Physicochemical properties of nitrogen rich in oil and char during biomass nitrogen-rich pyrolysis
Authors:Wen, Ming (1); Zhang, Shihong (1); Shao, Jing'ai (1); Chen, Yingquan (1); Feng, Lei (1); Wang, Xianhua (1); Chen, Hanping (1)
Author affiliation:(1) State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, China
Corresponding author:Zhang, Shihong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:229-235
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Biomass is one of the most important renewable resources. Pyrolysis for producing high value added products provides additional value for biomass energy utilization. Through the introduction of exogenous nitrogen in biomass pyrolysis in nitrogen-rich conditions, it can get high value of nitrogen-containing products, i.e. nitrogen-rich char and oil. In this study, wood chips were used as raw materials. The experiment was carried out in a fixed bed reactor at 350 to 850, and the effect of temperature and impregnation ratio(5%, 10%, 15%, 20%) on products yields, compositions and characteristics were investigated. Firstly, wood chips were immersed in different mass fractions of urea solution, stirred for 12 hours with a magnetic mixer at room temperature. The woodchips was then separated from solution by filtration and was dried after for 24 hours in an oven. The dried woodchips was then gone through pyrolysis and the bio-oil obtained at different temperatures was analyzed by gas chromatography-mass spectrometry. Derived bio-oil and char were also analyzed for their compositions to trace nitrogen mass transfer. The surface physicochemical property of the char under nitrogen-rich conditions was characterized using a diffuse reflectance infrared spectroscopy and X-ray photoelectron spectroscopy. With the rise of impregnation ratio, the yield of char and bio-oil had little change. Temperature had a remarkable effect on the yield and nitrogen content of boichar and bio oil. Change of product yields was mainly due to the three components (cellulose, ligin and semicellulose) decomposing at different temperatures, and to the volatilization of the secondary cracking at high temperature. The GC-MS results indicated that after treated with urea solution, biomass pyrolysis oil contains large amounts of nitrogen-containing chemicals that can be used to refine high value-added chemical products. The nitrogen-containing chemicals in the bio-oil mainly include aromatic amine, nitrogenous heterocyclic compounds and amide substances. As the temperature increased, the nitrogen content in pyrolysis bio-oil decreased. The larger of urea solution mass fraction, the more nitrogen-containing chemicals in the pyrolysis oil. Pyrolysis char surface contains large amounts of aromatic structure and abundant nitrogen-containing functional groups. Diffuse reflectance IR analysis showed that at the low temperature char surface was rich in C-N, and -NH groups caused by reactions of amino and bio-char. It was confirmed that introducing the exogenous nitrogen into the biomass pyrolysis process can produce nitrogen rich char with a large number of nitrogen-containing functional groups. With temperature increasing, various functional groups decomposed gradually. At 750 and 850 only some hydroxyl groups and carbonyl groups were left on the char surface. The urea solution mass fraction had less effect on the types of surface functional groups on the pyrolysis char, but impacted functional group intensity. XPS analysis revealed that the char surface mainly contained C=N, C-N and N-COO functional groups and at 850, the char surface only contained pyridine-N and pyrrole-N. This phenomenon could be explained by that thermal stability of pyridine-N and pyrrole-N was better than amide substances. At the pyrolysis temperature of 550, the carbon in pyrolysis char was mainly amorphous carbon. With temperature increasing, some aliphatic chain C-H bond, carbonyl and some oligomeric C-C bonds disappeared, while when the temperature reached 850, the carbon in char was dominated by graphite carbon. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Nitrogen
Controlled terms:Amides - Amorphous carbon - Aromatic compounds - Biofuels - Biomass - Chemical properties - Chemical reactors - Chemicals - Chromatography - Cracking (chemical) - Energy utilization - Gas chromatography - High temperature operations - Impregnation - Indicators (chemical) - Infrared spectroscopy - Mass spectrometry - Mass transfer - Metabolism - Physical properties - Pyridine - Pyrolysis - Reflection - Surface properties - Temperature - Thermodynamic stability - Urea - Wood chemicals - Wood products - X ray photoelectron spectroscopy
Uncontrolled terms:Diffuse reflectance infrared spectroscopy - Effect of temperature - Gas chromatography-mass spectrometry - Heterocyclic compound - Physicochemical property - Pyrolysis temperature - Surface functional groups - Wood chip
Classification code:423 Non Mechanical Properties and Tests of Building Materials - 523 Liquid Fuels - 524 Solid Fuels - 525.1 Energy Resources and Renewable Energy Issues - 525.3 Energy Utilization - 641.1 Thermodynamics - 641.3 Mass Transfer - 711 Electromagnetic Waves - 801 Chemistry - 801.2 Biochemistry - 802.1 Chemical Plants and Equipment - 802.2 Chemical Reactions - 804 Chemical Products Generally - 804.1 Organic Compounds - 811.2 Wood and Wood Products - 813.2 Coating Materials - 931.2 Physical Properties of Gases, Liquids and Solids
DOI:10.11975/j.issn.1002-6819.2015.13.032
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 14>
Accession number:20153101103483
Title:Optimization of technical parameters for making mulch from waste cotton and rice straw fiber
Authors:Chen, Haitao (1); Ming, Xianglan (1); Liu, Shuang (1); Zhang, Ying (1); Zhang, Hongchao (1)
Author affiliation:(1) College of Engineering, Northeast Agricultural University, Harbin, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:292-300
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The technology of plastic mulching was widely used, but its use depended on petroleum resources, which caused white pollution; straw was a rich resource in quantity, but large amount of waste straw was burned in the field, which caused the waste of resource and the environmental pollution at the same time. To solve the pollution of plastic film, plant fiber mulching has been developed, which was biodegradable mulching. There was lots of methyl cellulose in the biogas residue produced by anaerobic fermentation using ruminant feces. Crop residues, most often treated as waste material, could be used as raw material to produce biodegradable plastic membrane, and one technique may solve the white pollution brought by plastic mulching and the plant residue pollution. Waste cotton fiber came from human production and life with low price, so there was an urgent need to its re-utilization. Abandoned textiles were mostly disposed as garbage, and the recycle was very little, which resulted in serious waste of resource and environmental pollution. In abandoned textiles, cotton textiles were mostly confined, for cotton fiber was cut or broken, and through the re-processing, some low additional value products were produced, which hindered the establishment of the industrial chain of the waste textile recycling. In order to improve the utilization rate of waste cotton fabrics and crop straw, and provide technical support for making the biodegradable biogas residue fiber mulch, the processing and property of hybrid film produced by waste cotton and rice straw fiber were studied. The "skeleton" was waste cotton fiber, and filling material was rice straw fiber, with adding the additive that was environmental friendly. The method of four-factor and five-level quadratic regression orthogonal rotation center combination was applied. Beating degree, adding ratio, basis weight and wet strength agent were taken as influencing factors; dry tension strength and elongation, wet tension strength and elongation were objective variances. The results showed that: 1) The rank of the effect of 4 factors on dry tensile strength from high to low was as follows: adding ratio, wet strength agent, basis weight and beating degree; on dry elongation: basis weight, wet strength agent, adding ratio and beating degree; on wet tensile strength: basis weight, wet strength agent, beating degree and adding ratio; on wet elongation: wet strength agent, adding ratio, basis weight and beating degree; 2) Optimal technology parameters of hybrid film made from waste cotton-rice straw fiber were basis weight of 77-90 g/m<sup>2</sup>, wet strength agent of 1.5%-1.8%, beating degree of 45°SR and adding ratio of 25%; under this condition, dry tensile strength was greater than 32 N, dry elongation was greater than 2.0%, wet tensile strength was greater than 10 N, wet elongation was greater than 5.5%, and the film met the requirements of mechanical property for field mulching. Adding functional additives could make fibers' lap best, and reticular structure was formed so that the film was uniform and compact, and increased the intensity and stability; 3) Manufacturing film samples was according to the optimal process results, which were basis weight of 80 g/m<sup>2</sup>, wet strength agent of 1.6%, beating degree of 45°SR and adding ratio of 25%. Evaluation indicators were separately determined and 10 parallel tests were taken for the verifications. Experimental results indicated that dry tensile strength was 34.7 N, dry elongation was 2.19%, wet tensile strength was 11.4 N and wet elongation was 5.8%. The results were correct and credible. According to the standard of tensile strength and elongation, manufacturing environment-friendly biodegradable film with waste cotton and rice straw fiber is feasible. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Tensile strength
Controlled terms:Additives - Agricultural wastes - Biodegradable polymers - Biogas - Cotton - Cotton fibers - Crops - Elongation - Environmental technology - Fibers - Manufacture - Optimization - Petroleum deposits - Pollution - Recycling - Straw - Textile fibers - Textiles
Uncontrolled terms:Anaerobic fermentation - Biodegradable plastics - Environmental pollutions - Hybrid film - Manufacturing environments - Processing and properties - Strength and elongations - Waste cotton
Classification code:421 Strength of Building Materials; Mechanical Properties - 422 Strength of Building Materials; Test Equipment and Methods - 452.3 Industrial Wastes - 454 Environmental Engineering - 454.2 Environmental Impact and Protection - 512.1 Petroleum Deposits - 537.1 Heat Treatment Processes - 803 Chemical Agents and Basic Industrial Chemicals - 804 Chemical Products Generally - 812 Ceramics, Refractories and Glass - 817 Plastics and Other Polymers: Products and Applications - 819 Synthetic and Natural Fibers; Textile Technology - 819.1 Natural Fibers - 821.4 Agricultural Products - 821.5 Agricultural Wastes - 921.5 Optimization Techniques
DOI:10.11975/j.issn.1002-6819.2015.13.041
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 15>
Accession number:20153101103462
Title:Spatial variability and attribution analysis of water footprint of wheat in China
Authors:Sun, Shikun (1); Wang, Yubao (1); Wu, Pute (2); Zhao, Xining (2)
Author affiliation:(1) Key Laboratory for Agricultural Soil and Water Engineering in Arid Area of Ministry of Education, Northwest A&F University, Yangling, China; (2) Institute of Water Saving Agriculture in Arid Regions of China, Northwest A&F University, Yangling, China; (3) National Engineering Research Center for Water Saving Irrigation at Yangling, Yangling, China
Corresponding author:Wu, Pute
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:142-148
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Water use efficiency assessment is one of the core research items in water-saving agriculture. The water footprint (WF) of crop production is a comprehensive indicator reflecting water consumption types, quantities and water use efficiency during crop growth period. Based on the theory of water footprint, this study quantified and evaluated the regional differences of water footprint of wheat at the regional scale in Mainland China. Meanwhile, in order to find the dominant factors causing the regional differences of water footprint of wheat, correlation and path coefficient analysis were used to identify the relationship between water footprint of wheat and its impact factors. The results showed that there were obvious regional differences of water footprint of wheat in Mainland China. The water footprint of wheat was relatively low in the eastern part of Northeast China, most of Huang-huai-hai region, parts of the Lower-Middle Reaches of the Yangtze River and Sichuan province, which was less than 1 m<sup>3</sup>/kg; while the high values of water footprint of wheat were mainly distributed in Northwest China, the northwest of Inner Mongolia, the south of Lower-Middle Reaches of the Yangtze River and the south of Southwest China, which were more than 1.8 m<sup>3</sup>/kg. From the perspective of water type, the blue water footprint accounted for 49.02%, while the green water footprint accounted for 50.98% among the total WF of wheat. The green water proportion in wheat water footprint increased gradually from northern regions to southern regions. For instance, the proportion of green water footprint was 18.62% in Beijing, while it was more than 80% in most of southern regions. The regional distinction of green proportion in water footprint was in accordance with the precipitation on distribution. The region with abundant precipitation usually has a high proportion of green water in crop water footprint. There were 9 related factors selected for the attribution analysis: average temperature, relative humidity, growing season precipitation, solar radiation, wind speed, fertilizer consumption, pesticides consumption, agricultural machinery and irrigation share. The statistical analysis revealed that the regional variability of wheat water footprint, besides the crop varieties, was mainly caused by the regional disparities of agricultural production level, such as agricultural inputs and irrigation condition. On the other hands, the solar radiation and precipitation were the major climatic influencing factors causing the regional difference of water footprint of wheat. The indirect path coefficient of water footprint of wheat and its impact factors showed that solar radiation had indirect effects on water footprint through temperature, and precipitation mainly through relative humidity. Meanwhile, the fertilizer consumption, pesticides consumption, agricultural machinery power, irrigation had indirect effect on water footprint of wheat through each other influencing factors. The total influence coefficient analysis showed that the chemical fertilizer consumption, pesticides consumption, agricultural machinery and irrigation were the dominant factors that had an effect on water footprint of wheat. The results can provide information for plan-making of agricultural water management schedule. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Chemical analysis
Controlled terms:Agricultural machinery - Agriculture - Crops - Cultivation - Evapotranspiration - Factor analysis - Fertilizers - Irrigation - Pesticide effects - Pesticides - Precipitation (chemical) - Radiation effects - Solar radiation - Water - Water conservation - Water management - Water supply - Wind
Uncontrolled terms:Agricultural productions - Agricultural water management - Attribution analysis - Path coefficient analysis - Regional differences - Water footprint - Water-saving agricultures - Wheat
Classification code:443.1 Atmospheric Properties - 444 Water Resources - 446 Waterworks - 446.1 Water Supply Systems - 657.1 Solar Energy and Phenomena - 711 Electromagnetic Waves - 744 Lasers - 801 Chemistry - 802.3 Chemical Operations - 803 Chemical Agents and Basic Industrial Chemicals - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 922.2 Mathematical Statistics
DOI:10.11975/j.issn.1002-6819.2015.13.020
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 16>
Accession number:20153101103485
Title:Proper blending rate improving mechanical and rheological properties of low density polyethylene/bamboo composites
Authors:Song, Jianbin (1); Yuan, Quanping (1); Huang, Biao (2); Hou, Junfeng (1); Yang, Wenbin (2)
Author affiliation:(1) Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing, China; (2) College of Materials Engineering, Fujian Agriculture and Forestry University, Fuzhou, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:309-314
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In fact, the ultimate properties of wood-plastics composites (WPCs) not only rely on the structure, composition and morphology, but also depend on the processing conditions, such as processing temperature, pressure (blending rate) and time. Due to the degradation of bamboo powder under high processing temperature or long processing time, this paper studied mainly the effects of blending rate on the mechanical and rheological properties of low density polyethylene (LDPE)/bamboo powder composites, which were fabricated by the melt compounding method with the compounding temperature of 170 and 10 min, by using the rotational rheometer, material testing machine and scanning electron microscope (SEM). The maleic anhydride grafted polyethylene (MAPE) was selected as the compatibilizer for LDPE and bamboo powder. The mass proportion of LDPE, MAPE and bamboo powder was set to 65:5:30. The mechanical properties, water absorption and morphology of LDPE/bamboo composites were investigated in detail by changing the blending rate (40, 75 and 100 r/min). Before experiments, all the materials were dried in vacuum oven at 70 for 24 h. The addition of bamboo powder improved the tensile strength and flexural strength of LDPE, which were increased by 28% and 115% respectively compared to neat LDPE, but reduced the impact strength of LDPE. The tensile strength and flexural strength of the LDPE/bamboo composites decreased as the rotation rate increased from 40 to 100 r/min. The flexural modulus of LDPE/bamboo composites decreased from 48.45 to 40.75 MPa as blending rate increased from 40 to 100 r/min, and the highest flexural modulus increased by 238% compared to neat LDPE (14.35 MPa); however, the notched impact strength of LDPE/bamboo composites increased from 12.8 (40 r/min) to 18.27 kJ/m<sup>2</sup> (100 r/min), lower than that of neat LDPE (29.19 kJ/m<sup>2</sup>). For rheological experiments, the LDPE/bamboo composites exhibited shearing thinning behaviors, and at the same frequency, the complex viscosity of LDPE/bamboo composites decreased as blending rate increased, indicative of the improvement in processing performance; the storage modulus of LDPE/bamboo composites also reduced as blending rate increased, indicating the rigidness reduction, and this result was consistent with the results from mechanical properties. Also, the water absorption of LDPE/bamboo composites decreased from 0.89% (40 r/min) to 0.59 % (100 r/min). The reason was that the high blending rate caused the LDPE and bamboo powder to compound more evenly and the interfacial performance between LDPE and bamboo power was improved. The SEM results showed that at low blending rate (40 r/min), the bamboo powder surface was only coated with a thin layer of resin, and the interface between LDPE and bamboo powder was very clear, indicative of poor interfacial properties, and no plastic deformation was observed; at high rotation rate (100 r/min), bamboo powder was coated with a thick layer of polymer resin, exhibiting good interface performance with LDPE, and what's more, the big plastic deformation was observed in matrix, suggesting LDPE/bamboo composite (100 r/min) exhibited a good toughness. The above results confirmed that elevating blending rate could improve the toughness and reduce the water absorption of LDPE/bamboo composites, and in our experiments, the LDPE/bamboo composites, produced by blending rate (100 r/min), exhibited the better impact strength and water absorption. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Polymer matrix composites
Controlled terms:Bamboo - Bending strength - Blending - Composite materials - Density (specific gravity) - Impact strength - Low temperature testing - Mechanical properties - Plastic coatings - Plastic deformation - Polyethylenes - Processing - Resins - Rheology - Scanning electron microscopy - Temperature - Tensile strength - Vacuum applications - Water absorption
Uncontrolled terms:High processing temperatures - Interfacial performance - LDPE (low-density polyethylene) - Low density polyethylene(LDPE) - Notched impact strength - Processing temperature - Rheological experiment - Wood-plastics composite
Classification code:415 Metals, Plastics, Wood and Other Structural Materials - 421 Strength of Building Materials; Mechanical Properties - 633.1 Vacuum Applications - 641.1 Thermodynamics - 644 Refrigeration and Cryogenics - 802.3 Chemical Operations - 811 Cellulose, Paper and Wood Products - 811.1 Pulp and Paper - 813.2 Coating Materials - 815.1 Polymeric Materials - 815.1.1 Organic Polymers - 913.4 Manufacturing - 931.1 Mechanics - 931.2 Physical Properties of Gases, Liquids and Solids - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2015.13.043
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 17>
Accession number:20153101103454
Title:Design and application of drainage engineering in combination of ditch with ponds
Authors:Jiao, Pingjin (1); Xu, Di (1); Wang, Shaoli (1); Zhang, Xueping (3)
Author affiliation:(1) State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing, China; (2) National Center for Efficient Irrigation Engineering and Technology Research, Beijing, China; (3) Groundtopeak Tianpinghang Land Consolidation & Rehabilitation Co., Ltd, Beijing, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:83-88
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Drainage engineering technology combined with ditch and pond was proposed and its design method were developed to meet the challenge of increasing design discharge that had been caused by the increase of extreme rainfall events and variations of basin underlying surfaces. Considering drainage patterns and data shortage at small ungauged watershed, the design method consisted of the determinations of drainage criteria and drainage hydrograph, and the design of pond and weir sizes. Design storm amount was determined by the statistical analysis of long-term daily precipitation and local design return period, and the design storm duration, usually 24 h, was discretized based on storm temporal distribution (hourly) in local hydrology manual. Given that drainage hydrograph can be approximated by a triangular hydrograph at every discrete time interval, drainage hydrograph was synthetized each triangular hydrograph calculated with the improved SCS (soil conservation service-curve number) model and concentration equations every discrete time interval. Pond and weir sizes were estimated by the trial and error solution of the stage-storage function, weir equation and continuity equation, as the pond outflow rate was close to design drainage rate of the receiving ditch downstream. In the lowland of the northern Huaihe River Plain, the pond of 800 m<sup>2</sup> was designed for combining with field ditch and installed with the weir of 0.6 m wide and weir coefficient of 1.28, which would be used to drain the runoff from the area of 0.06 km<sup>2</sup>. The pond of 26000 m<sup>2</sup> was designed for combining with collector ditch and installed with the weir of 2.0 m wide and weir coefficient of 1.28, which would be used to drain the runoff from the area of 1.36 km<sup>2</sup>. The drainage engineering combined with the ditch and pond extended the time of concentration of 0.5 h for field ditch district and1 h for collector ditch district, respectively, under the return periods of 24 h storm of 3-year, 5-year and 10-year. The drainage engineering combined with the ditch and pond reduced peak storm flows of more than 25% under the return periods of 24 h storm of 3-year, 5-year and 10-year. Combined with the pond weir of 0.6 m wide and 0.7 or 0.85 m high, the drainage criteria of the field ditch could be increased from the return periods of 3-year or 5-year to the return periods of 5-year or 10-year, respectively. Combined with the pond weir of 2.0 m wide and 1.8 or 2.3 m high, the drainage criteria of the collector ditch could be increased from the return periods of 3-year or 5-year to the return periods of 5-year or 10-year, respectively. Drainage engineering technology combined with ditch and ponds could be an option to mitigate the flood damage of the drainage district and downstream. However, drainage engineering technology combined with ditch and ponds should be assessed for different weather and soil conditions, and the design parameters of ponds and weir should be evaluated to adapt different ditches and weather conditions. The effects of drought, flood and environment should be considered as the combined drainage engineering technology is used to control flood. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:16
Main heading:Drainage
Controlled terms:Balloons - Catchments - Design - Digital storage - Engineering technology - Flood control - Floods - Hydraulic structures - Lakes - Ponding - Ponds - Runoff - Soil conservation - Storms - Weirs
Uncontrolled terms:Concentration equations - Design and application - Discrete time intervals - Ditch - Hydrographs - SCS model - Soil conservation service - curve numbers - Time of concentrations
Classification code:401 Bridges and Tunnels - 402 Buildings and Towers - 406 Highway Engineering - 407 Maritime and Port Structures; Rivers and Other Waterways - 408 Structural Design - 441 Dams and Reservoirs; Hydro Development - 441.1 Dams - 442 Flood Control; Land Reclamation - 442.1 Flood Control - 443.2 Meteorological Instrumentation - 443.3 Precipitation - 444 Water Resources - 444.1 Surface Water - 454.1 Environmental Engineering, General - 454.3 Ecology and Ecosystems - 502 Mines and Quarry Equipment and Operations - 611 Hydroelectric and Tidal Power Plants - 722.1 Data Storage, Equipment and Techniques - 821.3 Agricultural Methods - 901 Engineering Profession - 902 Engineering Graphics; Engineering Standards; Patents
DOI:10.11975/j.issn.1002-6819.2015.13.012
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 18>
Accession number:20153101103453
Title:Model of coupling water with fertilizer and optimum combination scheme of rice cultivated in aerobic soil with drip irrigation under plastic film
Authors:He, Jinyu (1); Tian, Juncang (1)
Author affiliation:(1) College of Civil and Hydraulic Engineering, Ningxia University, Yinchuan, China; (2) Ningxia Research Center of Technology on Water-saving Irrigation and Water Resources Regulation, Yinchuan, China; (3) Engineering Research Center for Efficient Utilization of Water Resources in Modern Agriculture in Arid Regions, Yinchuan, China
Corresponding author:Tian, Juncang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:77-82
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Studies on how to improve the yield of rice, which are mostly affected by water and fertilizer, are receiving more and more attention. However, little is known about the coupling effect of irrigation and fertilizer on rice's yield and water production efficiency (WPE). This study aimed at investigating the relations of water and fertilizer with the yield of rice cultivated in aerobic soil with drip irrigation under plastic film. The field experiments were conducted to establish yield model of water and fertilizer coupling of rice. Two groups of tests were set up including a preliminary test conducted in Yinchuan Xixia in 2012, and verification test conducted in Yinchuan Xixia in 2013 and Yinchuan Helan in 2014.The annual average rainfalls were 208, 260 and 300 mm for the three year. By quadratic current rotary combination method, 3 treatments of irrigation quota, N and P<inf>2</inf>O<inf>5</inf> fertilizers with 5 levels for each were designed. Each plot was 25 m in length and 1.4 m in width, and plots were separated by 50 cm deep plastic film to prevent the cross penetration of water and fertilizer. The drip tapes were laid under plastic film, the dripper flow rate was 2 L/h. The rice variety was 96D10. Ternary quadratic regression model was used to fit relationship between yield and three treatments in 2012. The results showed that the model could well fit the relationship between the actual yield and irrigation, N and P fertilizer with the determination coefficient R<sup>2</sup> of 0.981. The main factor analysis for the model revealed that the effects of three treatments on yield was ordered in irrigation quota>N>P<inf>2</inf>O<inf>5</inf> fertilizers. In addition, the model was used to obtain optimal combinations of treatments for target yield and results showed that: 1) when the target yield of rice was 5000-6500 kg/hm<sup>2</sup>, the irrigation quota should be 2218.9-3087.3 m<sup>3</sup>/hm<sup>2</sup>, the N and P<inf>2</inf>O<inf>5</inf> fertilizers was 131.7-236.9 and 66.1-109.5 kg/hm<sup>2</sup>, respectively; 2)when the yield of rice was 6500-8000 kg/hm<sup>2</sup>, the irrigation quota should be 4219.6-5157.6 m<sup>3</sup>/hm<sup>2</sup>, and the N and P<inf>2</inf>O<inf>5</inf> fertilizers was 150.4-250.9 and 62.8-107 kg/hm<sup>2</sup>; 3)when the yield of rice was 8000-9500 kg/hm<sup>2</sup>, the irrigation quota should be 7453.2-8791.2 m<sup>3</sup>/hm<sup>2</sup>, the N and P<inf>2</inf>O<inf>5</inf> fertilizers should be 185.8-284.1 and 74.6-116.9 kg/hm<sup>2</sup>. By calculating the ratio of target yield and irrigation quota, the water production efficiency for target yield of 5000-6500, 6500-8000, and 8000-9500 kg/hm<sup>2</sup> should be 2.10-2.25, 1.54-1.55, and 1.07-1.08, respectively. The results in 2013 and 2014 were used for verifying the optimal results. The results revealed that the yield and water production efficiency in 2013 and 2014 based on the combined treatments all fell in range of target yield and water production efficiency. In summary, the optimal schedule for treatments and yield is helpful in saving water and fertilizers and keeping yield for rice cultivated in aerobic soil with drip irrigation under plastic film. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:11
Main heading:Irrigation
Controlled terms:Efficiency - Fertilizers - Models - Optimization - Plastic films - Plastic tapes - Regression analysis - Soils
Uncontrolled terms:Aerobic soil - Determination coefficients - Drip irrigation under plastic films - Irrigation and fertilizers - Optimal combination - Quadratic regression - Saving water and fertilizers - Yield
Classification code:483.1 Soils and Soil Mechanics - 804 Chemical Products Generally - 817.1 Polymer Products - 821.3 Agricultural Methods - 902.1 Engineering Graphics - 913.1 Production Engineering - 921.5 Optimization Techniques - 922.2 Mathematical Statistics
DOI:10.11975/j.issn.1002-6819.2015.13.011
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 19>
Accession number:20153101103460
Title:Spatio-temporal characteristics of soil bulk density and saturated hydraulic conductivity at small watershed scale on Loess Plateau
Authors:Fu, Zihuan (1); Wang, Yunqiang (1); An, Zhisheng (1)
Author affiliation:(1) State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, China; (2) College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
Corresponding author:Wang, Yunqiang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:128-134
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Surface soil bulk density (BD) and saturated hydraulic conductivity are two of important parameters to assess rainfall infiltration, runoff formation and soil erosion. But little research has been done at a watershed scale. On the Loess Plateau of China, investigations on the spatio-temporal changes of BD and saturated hydraulic conductivity at a small watershed scale are essential for regional ecological restoration and may enrich our understanding on the related eco-hydrolgical processes. In this study, we measured BD and saturated hydraulic conductivity in August, September, and October of 2014 at 73 sites that were pre-located by using Global Positioning System in a 50 m × 50 m grid at the LaoYeManQu watershed on the wind-water erosion crisscross region of the Chinese Loess Plateau. Using classical statistical and geostatistical methods, we characterized and compared the spatial and temporal changes of BD and saturated hydraulic conductivity. The semivariograms and kriging method included in the geostatistical method were used to reflect the visual variation among different months from August to October. Results showed that: 1) Among the three months, BD had a normal distribution and exhibited a time stability while saturated hydraulic conductivity had a skewed distribution and varied greatly. BD variation was smaller than that of the saturated hydraulic conductivity at the watershed scale. 2) Semivariograms of BD and saturated hydraulic conductivity from August to October could be best fitted by an isotropic exponential model. Both BD and saturated hydraulic conductivity exhibited a moderate spatial dependence. Distribution maps produced by kriging indicated pronounced spatial patterns of BD and saturated hydraulic conductivity at the small watershed-at the slope top and the western part of the watershed, BD demonstrated an increasing trend while saturated hydraulic conductivity decreased gradually from August to October. 3) Pearson correlation analysis showed that correlations between BD and saturated hydraulic conductivity at each measured time from August to October were weak (r<0.4); while, for the same soil type (dry sandy entisol) in the watershed, BD was correlated with saturated hydraulic conductivity negatively at the significant level of 0.01 and for aeolian soils the correlation was not significant. Our results suggested that different soil types in the watershed may change the overall correlation between BD and saturated hydraulic conductivity of the three months. Understanding the spatial and temporal variation of BD and saturated hydraulic conductivity would increase the accuracy in modeling and predicting rainfall infiltration, soil water and solutes movement at the watershed scale. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Hydraulic conductivity
Controlled terms:Correlation methods - Erosion - Infiltration - Interpolation - Landforms - Moisture - Normal distribution - Rain - Sediments - Soil moisture - Soils - Watersheds
Uncontrolled terms:Bulk density - Loess Plateau - Pearson correlation analysis - Saturated hydraulic conductivity - Spatial and temporal changes - Spatial and temporal variation - Spatio-temporal dynamics - Spatiotemporal characteristics
Classification code:443.1 Atmospheric Properties - 443.3 Precipitation - 444.1 Surface Water - 481.1 Geology - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 632.1 Hydraulics - 921.6 Numerical Methods - 922.1 Probability Theory - 922.2 Mathematical Statistics
DOI:10.11975/j.issn.1002-6819.2015.13.018
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 20>
Accession number:20153101103467
Title:Mapping paddy fields of Dongting Lake area by fusing Landsat and MODIS data
Authors:Zhang, Meng (1); Zeng, Yongnian (1)
Author affiliation:(1) School of Geosciences and Info-physics, Central South University, Changsha, China; (2) Center for Geomatics and Regional Sustainable Development Research, Central South University, Changsha, China
Corresponding author:Zeng, Yongnian
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:178-185
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The Dongting Lake area is one of the important commodity grain bases in the middle and lower reaches of Yangtze River, China, so we selected the Dongting Lake area as an example to extract the paddy area using Landsat data. But it was hard to get the time series Landsat data of the study area due to the rainy weather and return cycle of the satellite. In order to solve the problem of data missing in mapping paddy fields, we used STARFM (spatial and temporal adaptive reflectance fusion model) algorithm to blend MODIS and Landsat data, and got the high-frequency temporal information from MODIS and high-resolution spatial information from Landsat. Then the Savitzky-Golay(S-G), Gaussian and Double logistic filter were used to smooth the time series Landsat NDVI (normalized difference vegetation index) data. Through the comparative analysis, we found that the overall fidelity of Savitzky-Golay was the best. On one hand, the correlation coefficient between original NDVI value and fitting value was higher than the other 2 methods which were used to smooth the time series Landsat NDVI data. On the other hand, the root mean square error was smaller than the other 2 filters for land cover types except the forest. With the phonological calendar of crops and the computation of Jeffries-Matsushita distance (J-M), and through selecting validation data randomly throughout the study area for many times, we got the best J-M distance and the optimal Landsat NDVI data combination, and the optimal Landsat NDVI data combination was the 145th, 193rd, 241st, 273rd and 305th day. Support vector machine was used to map paddy area of study area next. Results showed that this method could map paddy fields effectively, and get a high overall precision of 94.52% with the Kappa coefficient of 0.9128. Producer's accuracies (PA) for double cropping rice, single season rice, cotton and forest was over 90%. The user's accuracies (UA) were over 90% except single season rice (88.42%), because 109 single season pixels were misclassified as double cropping rice, which was in compliance with the phenomenon that single season rice and double cropping rice had the lowest separability among all pair-wise vegetation types in the optimal scene combination, and it also proved that the mix-pixels characterized by small-area and dispersed distribution of single season rice among double cropping rice made it difficult to discriminate the 2 types of rice. Paddy rice area was 7.88×10<sup>5</sup> hm<sup>2</sup>, which was almost throughout the study area. Double cropping rice area was about 7.75×10<sup>5</sup> hm<sup>2</sup>. Obviously, the double cropping rice took the main part of rice planting, and its precision was 93.15% compared with statistical yearbook of Hunan Province in 2013, which mainly was concentrated in the north and northwest of the lake area. The distribution of double cropping rice was continuous. Distribution of single season rice was relatively scattered, small margin was in central and northwest of study area, and its area and precision were nearly 1.3×10<sup>4</sup> hm<sup>2</sup> and 88.16%. The precision of single season rice was lower than double cropping rice also due to the mix-pixel problem caused by scattered distribution of single season rice. Rice planting area was mainly concentrated in low altitude plain of the lake area, double cropping rice was mainly distributed in the north of the study area, like Hurong County and Nanxian County, and in the northwest of the lake area, like Anxiang County, Jinshi City, Lixian County and Dingcheng District, Changde City. Single season rice had a small range of area concentrated in the northwest and central of study area, like Lixian County and Nanxian County. The research can provide an important way to solve the problem of missing data on monitoring crop. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Data mining
Controlled terms:Balloons - Crops - Data fusion - Forestry - Image processing - Lakes - Mapping - Mean square error - Pixels - Problem solving - Radiometers - Remote sensing - Time series - Vegetation
Uncontrolled terms:Correlation coefficient - Dongting Lake area - LANDSAT - Middle and lower reaches of yangtze rivers - MODIS - Normalized difference vegetation index - Paddy - Root mean square errors
Classification code:407 Maritime and Port Structures; Rivers and Other Waterways - 652.5 Balloons and Gliders - 723.2 Data Processing and Image Processing - 723.5 Computer Applications - 731.1 Control Systems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 902.1 Engineering Graphics - 921 Mathematics - 922.2 Mathematical Statistics - 944.7 Radiation Measuring Instruments
DOI:10.11975/j.issn.1002-6819.2015.13.025
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 21>
Accession number:20153101103449
Title:Running stability control method and test verification of soil groove test rig for rotary agricultural machine
Authors:Sun, Xincheng (1); Ye, Jun (2); Yan, Jiangjun (1); Chen, Jianneng (1)
Author affiliation:(1) College of Mechanical Engineering and Automation, Zhejiang Sci-Tech University, Hangzhou, China; (2) Zhejiang Industry Polytechnic College, Shaoxing, China; (3) Zhejiang Province Key Laboratory of Transplanting Equipment and Technology, Hangzhou, China
Corresponding author:Chen, Jianneng
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:46-52
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Indoor soil groove tester is a test platform of the agricultural and mechanical properties, and it can carry out tests conveniently and can not be limited by the seasons and if a whole machine has been developed, which is an important equipment in the process of agricultural machinery research and development and performance improvement. Existing soil groove test bench is basically linear soil tank, which universally has some problems, such as being not able to carry out continuous test (because of the limited length of the soil groove, if you want to test continuously, it must be pulled back to the starting point to test), covering area too large and parameter test trouble (test instruments must move simultaneously with the measured object, in particular when the parameters of the trajectory and attitude are measured). For this purpose, a rotating type of soil flume test rig, which can carry out the continuous test and has small area and convenient parameter test, is proposed. But after testing, it is found that due to large mass of the groove body and the soil in the groove, acceleration and deceleration is not easy to be controlled and regulated, leading to test velocity fluctuations. In order to further improve the running stability of the rotating earth groove, based on the movement characteristics and speed change rule of previous research test bed, the fuzzy control and PI (proportional integral controller) control strategy are compared, and it is found that the fuzzy control is more suitable for the operation control of rotary soil bin tester and test rig in the process of speed change by multiple parameters. For the multivariable complex system, this paper establishes the fuzzy control mathematical model of rotary soil bin test bench, and simulation analysis is carried out and control system is designed, according to the results of the simulation experiments. Through the simulation analysis and experimental verification of operation stability of rotary soil groove tester, it is found that the fuzzy controller of test bench is running more stably, and its steady error is within 3.2%, which is more suitable for the control of rotary type earth groove. Simulation results show that for the soil tank, a maximum speed of 3.4 r/min appears at the moment of 3.8 s when the input speed of optimized fuzzy servo control soil tank driving motor is 300 r/min; and after 8.0 s, soil groove slot output speed is stable at 3 r/min, without oscillation in the late stage. In experiments, the servo motors of rotary soil groove test bench under fuzzy optimal control and fuzzy control are respectively input with 5 groups of initial speeds (36.7-320 r/min), the output speed and stability time of soil trough are measured, and the running stationarity error for soil trough is calculated. When the input speed of AC (alternating current) servo motor is maximum, the error of the running stationarity of the soil groove with the speed under fuzzy control is 0.034, and the error of the operation stationarity of the soil groove with optimized fuzzy control is 0.029. The improvement of the running stationarity of the rotary soil trough test bed can greatly improve the accuracy of the test of agricultural machinery on transplanting and sowing using the test bed. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Soil testing
Controlled terms:Agricultural machinery - Agriculture - Control systems - Controllers - Electric machine control - Equipment testing - Errors - Fuzzy control - Optimization - Soils - Speed - Stability - Tanks (containers) - Two term control systems
Uncontrolled terms:Acceleration and deceleration - Agricultural machine - Experimental verification - Movement characteristics - Proportional integral controllers - Research and development - Rotary type round soil groove - Velocity fluctuations
Classification code:483.1 Soils and Soil Mechanics - 619.2 Tanks - 731 Automatic Control Principles and Applications - 731.1 Control Systems - 732.1 Control Equipment - 801 Chemistry - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.1 Agricultural Machinery and Equipment - 921 Mathematics - 921.5 Optimization Techniques - 931 Classical Physics; Quantum Theory; Relativity - 931.1 Mechanics - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 951 Materials Science - 961 Systems Science
DOI:10.11975/j.issn.1002-6819.2015.13.007
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 22>
Accession number:20153101103476
Title:Quantitative estimation method and its application to rice, wheat and corn straw residues left in field
Authors:Wang, Yajing (1); Wang, Hongyan (1); Gao, Chunyu (1); Wang, Lei (1); Bi, Yuyun (1)
Author affiliation:(1) Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
Corresponding author:Bi, Yuyun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:244-250
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Straw residues left in the field include the crop stubbles, stems and leaves, part of the crushed straw remained in the field under the condition of reasonable harvest stubble. Besides collectable straw returned to field directly, leaving the straw residues in the field is the basic form of direct-application of straw into fields and this phenomenon could be widely seen throughout almost all the cropland in China. Researches on quantitative estimation of straw residues are of great significance to estimate the amount of collectable straw resources, evaluate the land productivity quantitatively and to make planning of direct-application of straw into fields etc. Formulas for estimating the quantity of straw residues left on the field were derived in this research. Five parameters were used in this study including average plant height, harvesting stubble height, leaf ratio, leaf fall rate, crops stalk loss ratio of mechanical collector. Parameters that estimated the quantity of wheat, corn and rice straw residues left in the field were determined by field surveys and literature analysis through selecting a large number of experimental data and survey data. The results showed that the amount of straw residues left on the field would increase gradually with the growing mechanical harvesting area. Total amount of straw returning to the field of China would increase to 600 000 000 t in ten years and that was 60% of the total production of crop straw. If the amount of collectable straw returning to field increased at the same time, the proportion and level of straw returning to the field would reach the level comparable to developed countries such as USA and Japan etc. In 2013, the amount of straw residues left on the field of three major crops of wheat, corn and rice in China was 71 069 200, 45 434 800 and 63 929 500 t, respectively. Straw residues left on the field of the whole nation was 253 300 800 t in the cropped area, and straw residues left on the field for the average per hectare of the sown area was 1.87 t. To meet the minimum requirement of the basic amount of straw residues directly returning to the field, this number should increase by 60% at least. Meanwhile, it should be expanded by 140% at least to meet the regular amount of straw residues directly returning to the field. The final part of this paper showed future needs for such research to calculate the quantity the straw residues applied into the field. The first is to carry out the extensive measure and calculation in the field, thus promotes the accuracy of the quantitative estimation parameters of straw residues of wheat, corn and rice, especially that of the harvesting stubble height and crops straw loss ratio of mechanical collector. The second is to carry out the quantitative estimation research on the straw residues of the economic crops as cotton, bean and rape etc., and further establish parameters of quantitative estimation of national major grain and economic crops' straw residues directly applied into the field. The third is to establish the parameters of quantitative estimation of regional straw residues directly applied into the field, and then gradually extend to apply this method to all the rest regions. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:12
Main heading:Parameter estimation
Controlled terms:Calculations - Crops - Estimation - Harvesting - Plants (botany) - Straw - Surveys
Uncontrolled terms:Developed countries - Five parameters - ITS applications - Land productivities - Literature analysis - Minimum requirements - Parametric -analysis - Quantitative estimation
Classification code:405.3 Surveying - 461.9 Biology - 731.1 Control Systems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921 Mathematics
DOI:10.11975/j.issn.1002-6819.2015.13.034
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 23>
Accession number:20153101103469
Title:Plant leaf vein edge detection based on fuzzy order morphology
Authors:Xu, Yanlei (1); Jia, Honglei (1); Bao, Jialin (2)
Author affiliation:(1) Key Laboratory of Bionics Engineering, Ministry of Education, Jilin University, Changchun, China; (2) College of Information, Jilin Agricultural University, Changchun, China
Corresponding author:Jia, Honglei
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:193-198
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Leaf is the important part of a plant, and leaf vein and edge feature are often used for classifying the plant. Leaf vein and edge features can also indicate the growing condition of plant. Leaf vein and edge extraction is useful for studying leaf and plant structures. However, it is difficult to obtain the accurate leaf vein and edge because of uncertainties in the process of image acquisition and processing. So the extraction algorithm of leaf vein and edge is required. The traditional algorithms can detect leaf edge and vein, but the interference immunity is poor and is easily affected by noise. So the edge is not complete and it is difficult to detect the complicate edge and small vein. The tradition algorithm is not adequate to feature extraction of plant leaf in complicated conditions. Recently, the new extraction methods are emerging, including neural network, fuzzy theory, and morphology, etc. However, each algorithm has its own limitations the result of extraction is not ideal. In this paper, plant leaf vein and edge extraction based on fuzzy order morphology was proposed. The proposed method combined the fuzzy theory and order morphology to extract the leaf vein and edge. Firstly, in this study, we constructed membership function according to the pixel neighborhood characteristic, which was based on the difference between the leaf vein edge and inner filed. The leaf image was transformed from the spatial domain to the fuzzy domain. The value of membership reflected the subjection of pixel to edge or vein. We also made the curve of membership function, which intuitively showed the distribution of pixel to edge or vein. Secondly, fuzzy rule and fuzzy inference needed to be proposed. The good rule and inference could obtain a good enhancement. We defined the fuzzy rule according to Sugeno fuzzy model, which could increase the difference of edge and inner area. If the value of membership was high, the value was higher by fuzzy inference and vice versa. We chose the power function as the fuzzy rule. When the x(x was the value of membership and value range was 0 to 1) was vein or edge, the exponent value was far less than 1. When x was in inner area, the value of x could keep up, so the exponent value was 1.Next, we extracted the vein and edge using the order morphology. In order morphology, when structure element was in flat area, the output image was almost same to the input; but when structure element was in changing area, the output image fell or rose on the vein or edge, which made a large difference between the input and the output image. By use of those, the vein and edge of leaf can be extracted. After enhancement, the plant leaf's vein and edge was more obvious. The order morphological transformation could make the vein and edge area gray scale more obvious. We constructed three edge detection operators, which could choose different structure element and different percent. The vein and edge of leaf could be obtained using the three operators. At last, we chose the leaf in natural situation and made simulation using MATLAB 7.0. To verify the effectiveness of the algorithm, we conducted several groups of experiments. The results showed that the proposed algorithm this paper could extract the vein and edge accurately. Comparing to several tradition algorithm, the edge was clearer and pseudo edge was disappear, and the noise could also be suppressed. The fuzzy edge and small vein could be detected after fuzzy transform. The proposed algorithm in this paper took into account of the difference between edge pixel and inner pixel in defining the membership function. The difference was further increased by fuzzy inference using fuzzy rule. So the algorithm could detect much clear and accurate leaf vein and edge, which has wide application. The method also can provide tools for classifying plant and monitoring the growing condition. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Fuzzy inference
Controlled terms:Algorithms - Edge detection - Extraction - Feature extraction - Fuzzy rules - Image acquisition - Image processing - MATLAB - Membership functions - Morphology - Pixels
Uncontrolled terms:Edge-detection operators - Extraction algorithms - Interference immunity - Neighborhood characteristics - Order morphological transformation - Order morphologies - Plant leaf - Plants
Classification code:716 Telecommunication; Radar, Radio and Television - 723 Computer Software, Data Handling and Applications - 741 Light, Optics and Optical Devices - 802.3 Chemical Operations - 921 Mathematics - 921.4 Combinatorial Mathematics, Includes Graph Theory, Set Theory - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2015.13.027
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 24>
Accession number:20153101103450
Title:Analysis on pressure pulsation under different impeller diameters in double channel sewage pump
Authors:Tan, Minggao (1); Ding, Rong (1); Liu, Houlin (1); Dong, Liang (1); He, Naichang (1)
Author affiliation:(1) Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:53-59
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The impeller diameter is one of the fundamental parameters of double channel sewage pumps. In order to analyze the effect of different impeller diameters on pressure fluctuation, the unsteady characteristics of a double channel sewage pump was numerically simulated by using the Mixture multiphase flow model and the developed standard k-Ε turbulence model. The double channel pump mainly consisted of volute, impeller, inlet extension and outlet extension. In order to improve the calculation stability, the impeller totally rotated for 18 cycles in the simulation and the total computation time was 0.3724 s. The simulation results of the last 2 periods were used to analyze the pressure fluctuation in the pump. Monitoring points were set in the middle of each section in volute circumference and in the tongue region so as to analyze the distribution and variation of the pressure fluctuation with the impeller diameter in the volute especially around the tongue. The calculation results were compared with the experimental data when the impeller diameter was 103 mm. The experiment was conducted in an open test platform, and the test measured the hydraulic performance of the pump and the pressure pulsation of the volute outlet. The pump head and efficiency deviation between calculated and experimental results were 2.37% and -0.46% respectively under the design condition, while the errors were slightly larger but less than 5% under other conditions, which illuminated that the numerical model and calculation methods predicted the hydraulic performance of double channel sewage pump extremely well so that it could be used to predict the characteristics under other impeller diameters. The pressure pulsation trend between calculated and experimental results fitted well and the error was small, which demonstrated that the CFD (computational fluid dynamics) method was able to forecast the distribution and variation of pressure pulsation in the pump accurately. The results showed that the pressure fluctuation of volute circumference under the design condition generally got weaker with the addition of certain amount of particles and the maximum decreased by 30.9%, and the average pressure pulsation reduction of the volute circumferential points decreased with the increase of impeller diameter. The results made clear that selecting appropriate impeller diameter could contribute to prevent pressure pulsation and the induced vibration and noise in the pump when transporting solid-liquid two-phase flow. The pressure fluctuation around the tongue got more and more sharply with the increase of impeller diameter when the water included proper amount of particles. The dominant frequency of points near the tongue was almost the blade passing frequency. Compared with water, the maximum amplitude of the reduction of the pressure pulsation increased and then decreased with the increase of impeller diameter, and the maximum reduction was 22.7%. The lower point of these points in the tongue region was affected maximumly by the rotor-stator interaction between impeller and volute. Instantaneous static pressure of every monitoring point fluctuated sharply when impeller diameter increased to 105 mm under solid-liquid two-phase flow. Selecting the appropriate impeller diameter could contribute to weaken the pressure pulsation when transporting solid-liquid two-phase flow. The study indicates that the impeller diameter has a very important impact on the distribution and variation of the double channel sewage pump and it provides the basis for the optimization design of double channel sewage pump. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Two phase flow
Controlled terms:Computational fluid dynamics - Impellers - Industrial plants - Liquids - Numerical methods - Pumps - Sewage - Sewage pumps - Turbulence models
Uncontrolled terms:Blade passing frequency - CFD (computational fluid dynamics) - Double channel - Modeling and calculations - Pressure pulsation - Rotor-stator interactions - Solid-liquid two phase flows - Unsteady characteristics
Classification code:402.1 Industrial and Agricultural Buildings - 452.1 Sewage - 601.2 Machine Components - 618.2 Pumps - 631.1 Fluid Flow, General - 921.6 Numerical Methods - 931.2 Physical Properties of Gases, Liquids and Solids
DOI:10.11975/j.issn.1002-6819.2015.13.008
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 25>
Accession number:20153101103452
Title:Energy management control strategy and optimization for plug-in 4WD hybrid electric vehicle
Authors:Qian, Lijun (1); Qiu, Lihong (1); Xin, Fulong (1); Chen, Peng (1); Wang, Jinbo (1)
Author affiliation:(1) School of Mechanical and Automotive Engineering, Hefei University of Technology, Hefei, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:68-76
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:For a plug-in four-wheel-drive hybrid electric vehicle (4WD PHEV), there are 3 power components which can work independently or cooperatively. Therefore, it has many work modes and the energy management control is relatively complicated. As the calculation of the torque request of the driver by the gas pedal travel only is not precise and that method can't reflect the driver's intention, especially the intensity of the acceleration, thus rendering bad power performances and fuel consumption. And to overcome the inherent defects of fuzzy logic and fuzzy PID (proportion integration differentiation) that they relied on prior knowledge to set the parameters and it was difficult to realize good control effect, it was put forward in this paper that the torque identification coefficient could be obtained through RBF (radial basis function) neural network, whose inputs were the gas pedal travel and its change rate, and the output was the torque identification coefficient. The parameters were obtained through experiments and the neural network model was trained to achieve a better accuracy. After the training, the output error was 0.063, which indicated that it was within the required range. The torque request calculation formula was put forward which took account of the torque identification coefficient. Considering the transient characters of the power components, the dynamic models of the power components and the vehicle were built. A control strategy in which the engine should work at the best efficiency when it worked was adopted. The work modes of the car were classified into EV (electric vehicle) mode, series mode, E-charge (engine drive and charge) mode, parallel mode, and 4WD mode. In addition, the rules for each mode and the dynamic functions were briefly presented. The Stateflow diagram of the control strategy was built in Simulink and was shown in the paper. Afterwards, the dynamic programming (DP) was adopted to obtain the optimal output sequence of the power components with the profile given, which was used as a comparison of the control effects with the rule-based strategy. The principle of DP was briefly introduced with a schematic diagram. The state variable of the DP was the state of charge (SOC) of the battery, and the control variables were the output torque of the integrated starter generator (ISG motor), rear motor and the ratio of continuously variable transmission (CVT). The state transition equation, the constraints and cost function were presented. Furthermore, a correctional DP-based (CDP) strategy was put forward to reduce the calculation time and the optimization steps were briefly introduced, as well as the principle of CDP. As a result, the running time of the program under a cycle of 1 180 s was reduced to 14.29% of that before correction, from 14 368 to 2 053 s. In the end, a hardware-in-the-loop test bench, which consisted of the power components, battery and sensors, etc, was built in Simulink/Motohawk, and the control strategies were compiled into executive codes with D2P (development to product) tools and were tested on the hardware-in-the-loop test bench. The results validated that the rule-based control strategy and the correctional DP-based strategy could realize good control effects. With RBF neural network torque request identification, the velocity error was obviously reduced and the fuel consumption was improved by 4.54%, while with the correctional DP-based strategy, the fuel consumption had another 14.04% reduction. The research methods in this paper can work as a reference when dealing with the control strategies of similar complicated hybrid electric vehicles. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Plug-in hybrid vehicles
Controlled terms:AC generator motors - All wheel drive vehicles - Amphibious vehicles - Battery management systems - Charging (batteries) - Cost functions - Dynamic programming - Electric batteries - Electric machine control - Electric machine theory - Energy management - Engines - Equations of state - Fuels - Fuzzy logic - Hardware - Hybrid vehicles - Industrial management - Ionization of gases - Neural networks - Optimization - Radial basis function networks - Schematic diagrams - Secondary batteries - Software testing - Synthetic apertures - Torque - Traction motors - Vehicles
Uncontrolled terms:Continuously variable transmission - Energy management control strategies - Energy management controls - Hardware in loop - Hardware-in-the-loop tests - Integrated starter generator - Proportion integration differentiations - Rule-based control strategies
Classification code:421 Strength of Building Materials; Mechanical Properties - 432 Highway Transportation - 522 Gas Fuels - 523 Liquid Fuels - 524 Solid Fuels - 525 Energy Management and Conversion - 605 Small Tools and Hardware - 612 Engines - 612.2 Diesel Engines - 662 Automobiles and Smaller Vehicles - 663 Buses, Tractors and Trucks - 674.1 Small Marine Craft - 702.1 Electric Batteries - 702.1.2 Secondary Batteries - 703.1 Electric Networks - 705 Electric Generators and Motors - 716.2 Radar Systems and Equipment - 721.1 Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory - 723.4 Artificial Intelligence - 723.5 Computer Applications - 802.2 Chemical Reactions - 912.2 Management - 921 Mathematics - 921.5 Optimization Techniques
DOI:10.11975/j.issn.1002-6819.2015.13.010
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 26>
Accession number:20153101103480
Title:Variation and distribution characteristics of O<inf>2</inf>, CO<inf>2</inf> concentration in controlled atmosphere storage by CFD
Authors:Zhou, Bo (1); Nan, Xiaohong (1); Wen, Gaili (1)
Author affiliation:(1) School of Environment and Municipal Engineering, Xi'an University Of Architecture And Technology, Xi'an, China
Corresponding author:Nan, Xiaohong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:274-280
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Concentration of O<inf>2</inf> and CO<inf>2</inf> has a great effect on storage quality of cold stored fruits or vegetables. Obtaining concentration variation and distribution characteristics of O<inf>2</inf> and CO<inf>2</inf> concentration in a controlled atmosphere storage (CA storage) can provide theoretical basis for optimal design and operation of CA storages. Hence, a combination of CFD calculation and experimental study were carried out to study the complicated phenomenon of air flow, heat and mass transfer in CA storage. An unsteady, 3D (three-dimensional) global CFD model was established for a real CA storage for apples in Xian. The CFD model includes k-Ε turbulent model and species transport model. The apple zone was regarded as porous medium zone. Air cooler was equipped in the storage. User-Defined-Function (UDF) programs were developed in C language to achieve the variation of apples' respiration rate and mass fractions of gas species at the velocity-inlet boundary along with the local O<inf>2</inf> and CO<inf>2</inf> concentration in the CA storage. The mass transfer phenomenon for the reduction process of O<inf>2</inf> concentration was numerically studied. The calculated concentration variation of O<inf>2</inf> and CO<inf>2</inf> were validated by experimental results. The experimental system consisted of a gas probe, gas analyzer and accessory measuring device. The gas probe was set inside the gas zone of the CA storage and connected to a gas analyzer at test room, where the piece of gas from the probe was measured and analyzed in every two hours. The numerical results were compared with the experimental data for whole reduction process of O<inf>2</inf> concentration, including the reduction process of O<inf>2</inf> concentration when N<inf>2</inf> generator was working followed by the reduction process due to apples' aerobic respiration when N<inf>2</inf> generator was stopped. The numerical results from the displacement process of O<inf>2</inf> by inputting N<inf>2</inf> indicated that the concentration of O<inf>2</inf> in gas zone decreased in an exponential function, which was validated by experimental results with a deviation of 0.027. The numerical results from the following reduction process due to apples' aerobic respiration were validated with the average differences of 3.06% for O<inf>2</inf> and 16.2% for CO<inf>2</inf> concentration. Moreover, increasing N<inf>2</inf> concentration of N<inf>2</inf> generator would shorten the reduction process of O<inf>2</inf>. In the case of studied CA storage, O<inf>2</inf> concentration decreased faster in gas zone than in apple zone in the beginning 4.1 h, but appeared the opposite characteristic afterwards. Concentration of CO<inf>2</inf> increased similarly in gas zone and in apple zone. Concentration of CO<inf>2</inf> decreased gradually with time. The concentrations of O<inf>2</inf> and CO<inf>2</inf> in gas zone appeared to be relatively uniform, but there existed concentration gradients in apple zone. The proposed 3D unsteady model can be used to get the reasonable reduction time of O<inf>2</inf> concentration for CA storage, which would provide a valuable reference for choosing reasonable N<inf>2</inf> generator. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:20
Main heading:Concentration (process)
Controlled terms:C (programming language) - Carbon - Carbon dioxide - Computational fluid dynamics - Digital storage - Exponential functions - Fruits - Gases - Ionization of gases - Mass transfer - Metal drawing - Oxygen - Porous materials - Probes
Uncontrolled terms:3-D (three-dimensional) - Concentration gradients - Concentration variation - Controlled atmosphere storage - Distribution characteristics - Gas component - Mass transfer phenomena - Species transport models
Classification code:535.2 Metal Forming - 641.3 Mass Transfer - 722.1 Data Storage, Equipment and Techniques - 723.1.1 Computer Programming Languages - 723.5 Computer Applications - 802.3 Chemical Operations - 804 Chemical Products Generally - 804.2 Inorganic Compounds - 821.4 Agricultural Products - 921 Mathematics - 921.6 Numerical Methods - 931.1 Mechanics - 931.2 Physical Properties of Gases, Liquids and Solids - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2015.13.038
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 27>
Accession number:20153101103457
Title:Effect of liquid mulch on physiological characteristics and yield of drip irrigated cotton
Authors:Li, Yunguang (1); Wang, Zhenhua (1); Zhang, Jinzhu (1); Li, Wenhao (1)
Author affiliation:(1) College of Water Resources and Architectural Engineering, Shihezi University, Shihezi, China; (2) Key Laboratory of Modern Water-saving Irrigation Corp, Shihezi University, Shihezi, China
Corresponding author:Zhang, Jinzhu
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:105-112
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Cotton is an important cash crop widely planted in the northwest arid area of China where plastic films have long been coupled with drip irrigation in crop cultivation to keep soil moisture and raise crop yield. However, as plastic films are difficult to degrade, the so-called white pollution caused by film residuals left in the soils has become an ever severer issue in cotton fields in arid areas due to long time use of plastic films and ineffectiveness of the recycle measures. In contrast to plastic films, liquid mulch, an organic polymer, is environmental friendly because it degrades naturally. To find out the feasibility of replacing plastic films with liquid mulch in drip irrigated cotton fields and the appropriate dosage of liquid mulch for optimal plant physiological characteristics and in turn crop yield, a bucket experiment was conducted on drip irrigated cotton. A total of five treatments were set up including 3 treatments with liquid mulch at different dosages, 1900 kg/hm<sup>2</sup> (LFD1), 2200 kg/hm<sup>2</sup> (LFD2), and 2500 kg/hm<sup>2</sup> (LFD3), one treatment with common plastic film (PFD) and a bare soil control (CK) without liquid mulch or common plastic film. The influence of liquid mulch on the physiological characteristics (i.e., leaf net photosynthetic rate, transpiration rate, stomatal conductance and intercellular CO<inf>2</inf> concentration), water use efficiency (WUE), yield components (i.e., boll number per plant and single boll weight) and cotton yield was monitored and analyzed. The results showed that liquid mulch dosage had important influence on the physiological characteristics indexes, WUE and cotton yield. With increase in liquid mulch dosage, leaf net photosynthetic rate, transpiration rate, stomatal conductance, intercellular CO<inf>2</inf> concentration and yield increased and became closer to those in PFD. The influence of liquid mulch on the physiological characteristics of drip irrigated cotton was more significant in the early and middle growth stages of cotton when physiological activities were active and became less significant with time in the late growth stage of cotton. Leaf net photosynthetic rate was significantly higher (P<0.05) in the 3 treatments with liquid mulch (i.e., LFD1, LFD2 and LFD3) than in CK at all the measuring times; liquid mulch at different dosages had different influences on leaf net photosynthetic rate in different cotton growth stages or at different measuring time periods of a same growth stage. Leaf net photosynthetic rate in LFD1, LFD2 and LFD3 measured at 14:00 of June 26 when cotton was in its bud stage with relatively vigorous physiological activities was 11.12%, 29.76% and 40.20% higher, respectively, than in CK but 24.96%, 12.38% and 5.33% lower, respectively, than in PFD; WUE, boll number per plant, single boll weight and yield in treatments with liquid mulch were significantly higher (P<0.05) than those in CK but these indexes were not significantly different (P>0.05) between the treatment with the highest dosage (2500 kg/hm<sup>2</sup>) of liquid mulch (LFD3) and PFD. Cotton yield in LFD1, LFD2 and LFD3 was 7.10%, 11.79% and 14.39% higher, respectively, than in CK. Liquid mulch at different dosages had important influences on the WUE and yield of drip irrigated cotton, and liquid mulch influenced cotton WUE and yield by continuously influencing its physiological characteristics. An appropriate amount of liquid mulch (not less than 2500 kg/hm<sup>2</sup>) coupled with drip irrigation had comparable water-saving and yield-increasing effects (relative to the bare soil control) to plastic film coupled with drip irrigation. Liquid mulch can replace plastic films in drip irrigated cotton fields without sacrificing crop yield. In addition, the natural degradability and pollution-free feature of liquid mulch provides a promising approach to address the white pollution issue in cotton fields of arid and semiarid areas. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:17
Main heading:Liquids
Controlled terms:Agriculture - Arid regions - Climate change - Cotton - Crops - Evapotranspiration - Irrigation - Liquid films - Organic polymers - Photosynthesis - Physiology - Plastic films - Pollution - Polymer films - Soil moisture - Soils - Subirrigation - Transpiration - Water conservation - Water supply
Uncontrolled terms:Arid and semi-arid areas - Drip irrigation - Environmental-friendly - Net photosynthetic rate - Physiological activity - Physiological characteristics - Water use efficiency - Yield
Classification code:443 Meteorology - 444 Water Resources - 444.1 Surface Water - 446.1 Water Supply Systems - 451 Air Pollution - 454.2 Environmental Impact and Protection - 461.9 Biology - 483.1 Soils and Soil Mechanics - 741.1 Light/Optics - 815.1 Polymeric Materials - 815.1.1 Organic Polymers - 817.1 Polymer Products - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 931.2 Physical Properties of Gases, Liquids and Solids
DOI:10.11975/j.issn.1002-6819.2015.13.015
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 28>
Accession number:20153101103484
Title:Process of degumming by chemical for banana pseudostem fibers and characterization of degummed fibers
Authors:Xu, Shuying (1); Tan, Wei (1); Zhang, Yucang (2)
Author affiliation:(1) College of Chemical Engineering & Technology, Tianjin University, Tianjin, China; (2) Key Laboratory of Solid Waste Resource Utilization and Environmental Protection, Hainan University, Haikou, China
Corresponding author:Zhang, Yucang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:301-308
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Natural fibers have growing demands in textile industry due to its availability, eco-friendliness, renewability, CO<inf>2</inf>-neutrality, flexibility, low density and low cost. Banana pseudostem fibers (BPSFs) can be a potential candidate to replace the synthetic fibers. However, there are still limitations for their application in textile industry because of their poor quality, such as "coarseness, shortness, hardness and crispness". This paper described one chemical method for extracting finer natural BPSFs from natural banana pseudostem. The effects of different pre-acid, pre-oxygen and alkali cooking processes on degumming rate and residual lignin rate of BPSFs were studied. The better degumming process was determined. The physicochemical properties of BPSFs treated chemically were analyzed by using the Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM). FTIR revealed structural modification after chemical treatments. SEM was used to evaluate the fracture morphology of failed samples. The tensile properties of BPSFs treated chemically were also investigated. The result showed that the pre-acid process condition was 2 g/L H<inf>2</inf>SO<inf>4</inf> aqueous solution at 55 for 2 h, where the external wax could be removed. The pre-oxygen process was achieved by immersing the banana pseudostem in a 200 mL mixture liquid composed of 7 g/L H<inf>2</inf>O<inf>2</inf>, 3wt% Na<inf>2</inf>SiO<inf>3</inf> and 2wt% sodium polyphosphate at 95 for 1.5 h. Afterwards, The sample was immersed in 200 mL NaOH solution of 9 g/L at boiling temperature for 3 h, then washed with 1 g/L H<inf>2</inf>SO<inf>4</inf> for 2-3 min to neutralize the residual alkali in the sample. Under the conditions, the residual gum rate of BPSFs treated chemically was 20.80%, and the residual lignin rate was 8.21%. BPSFs treated chemically were white and clean, and consisted of a large number of fine micro fibrils with a diameter of from 0.05 to 0.09 mm. In addition, BPSFs treated chemically were soft. FTIR results showed that most of the hemicelluloses and lignin were removed by chemical treatments, and the relative crystallinity index of BPSFs treated chemically was 61.2%. The SEM of longitudinal morphologies of BPSFs treated chemically had a cleaner, rougher, and fibrillated fiber surface due to dissolution of hemicelluloses and lignin. The SEM diagram indicated the BPSFs treated chemically exhibited a combination of ductile and brittle failure. Tensile test was carried out on single fiber according to the ASTM D 3822-01 standard. The diameter of BPSFs treated chemically was within the range of 0.068 mm, and the tensile strength, Young's modulus and elongation rate were 353.09 MPa, 18.34 GPa and 1.70% respectively. The tensile strength and elongation rate were enhanced by 13% and 6.5% respectively in the BPSFs treated chemically compared to those of untreated ones. And the Young's modulus was decreased by 14% in the BPSFs treated chemically compared to those of untreated ones. The tensile properties of BPSFs treated chemically were correlated with the results of FTIR, XRD and SEM. Based on the properties of BPSFs treated chemically, we expect that these fibers will be suitable for the use as textile materials. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Fibers
Controlled terms:Cellulose - Chemical modification - Degumming - Elastic moduli - Fourier transform infrared spectroscopy - Fruits - Infrared spectroscopy - Lignin - Natural fibers - Scanning electron microscopy - Sodium - Solutions - Tensile properties - Tensile strength - Tensile testing - Textile industry - Textiles - X ray diffraction
Uncontrolled terms:Banana pseudostem fiber - Fourier transformed infrared spectroscopy - Physicochemical property - Relative crystallinity - Residual lignins - Sodium polyphosphate - Strength and elongations - Structural modifications
Classification code:421 Strength of Building Materials; Mechanical Properties - 422 Strength of Building Materials; Test Equipment and Methods - 422.2 Strength of Building Materials : Test Methods - 549.1 Alkali Metals - 741.1 Light/Optics - 801 Chemistry - 802.2 Chemical Reactions - 803 Chemical Agents and Basic Industrial Chemicals - 804 Chemical Products Generally - 812 Ceramics, Refractories and Glass - 815.1.1 Organic Polymers - 817 Plastics and Other Polymers: Products and Applications - 819 Synthetic and Natural Fibers; Textile Technology - 821.4 Agricultural Products - 822.2 Food Processing Operations - 931.3 Atomic and Molecular Physics - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2015.13.042
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 29>
Accession number:20153101103446
Title:Effect of sowing date on yield component characteristics of mechanically transplanted rice
Authors:Xing, Zhipeng (1); Cao, Weiwei (1); Qian, Haijun (1); Hu, Yajie (1); Zhang, Hongcheng (1); Dai, Qigen (1); Huo, Zhongyang (1); Xu, Ke (1); Wei, Haiyan (1); Guo, Baowei (1); Luo, Xuechao (2); Li, Dejian (2); Liu, Guolin (2)
Author affiliation:(1) Innovation Center of Rice Cultivation Technology in the Yangtze Valley, Ministry of Agriculture/Key Laboratory of Crop Genetics and Physiology of Jiangsu Province, Yangzhou University, Yangzhou, China; (2) Bureau of Agriculture of Xinghua County of Jiangsu Province, Xinghua, China
Corresponding author:Zhang, Hongcheng
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:22-31
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Optimizing sowing date is the key cultivation measure to raise rice yield. Blanket-seedling mechanically transplanted rice has been used in a large production area in China. But study of how yield component characteristics of blanket-seedling mechanically transplanted rice response to different sowing date is relatively few. Therefore, there is a need for asystematic comparative study. In order to reveal the effect of sowing date on the yield component characteristics of different varieties of mechanically transplanted rice, a series of field experiments were conducted in 2012 and 2013 in the rice region of the middle of Jiangsu provinces under typical annual rice-wheat cropping rotation system with widely used rice cultivars of super japonica rice Wuyunjing 24 and indica-japonica hybrid rice Yongyou 2640. These cultivars are high in yield potential. The research were aiming to systematically analyze the dynamics of population stems and tillers, panicle characteristics, grain filling properties, and so on in different sowing date for mechanically transplanted rice. The results indicated that, with the delayed sowing date, population stems and tillers of mechanically transplanted rice increased with tillers during the earlier stage of growth, but those tillers died out rapidly during the middle and last stage of rice growth, causing a reduction of panicle maturity and obviously reducing the ratio of productive tillers to total tillers. Stem population and tillers from seedlings of early sowing dates were significantly (P<0.05) different from those in late sowing dates. When the sowing date was delayed, the panicle of mechanically transplanted rice was lessened. All of the panicle length, grain density, grain weight per panicle, ratio of No. of primary branches to No. branches of secondary branches, No. of branches per primary and secondary branch, grain number per primary and secondary branch and grain number per branch, seed-setting rate of primary branch and secondary branch were decreased. But ratio of total grains of primary branches to total grains of secondary branches was increased. Variations of characteristics in the indica-japonica hybrid large panicle rice were more drastic. There was no difference in the ratio of No. of primary branches to No. branches of secondary branches, and the ratio of total grains of primary branches to total grains of secondary branches and grains of primary branch. However, the other indexes of panicle were of significant (P<0.05) difference between early sowing and late sowing date. The postponed sowing date reduced the final weight of kernel of both the superior grains and inferior grains, resulting in grain weight decrease. With the sowing date delayed, the maximum grain-filling rate and mean grain-filling rate of superior grains were weakened. The time reaching the maximum grain-filling rate was delayed, and both the active grain-filling period and effective grain-filling time prolonged. The maximum grain-filling rate and mean grain-filling rate of inferior grains were not significantly(P>0.05) different, but maximum grain-filling rate and mean grain-filling rate in the fifth sowing date was the lowest, from which the time required to reach the maximum grain-filling rate delayed, the active grain-filling period shortened, and the effective grain-filling time prolonged. In conclusion, the suitable early sowing dates for mechanically transplanted rice would benefit rice production as followings: 1) stem population and tillers of mechanically transplanted rice was steadilyincreased; 2) panicles of maturity was adequate, the panicle structure was optimized, and seed setting rate was improved; and 3) the grain-filling time was longer, while the grain-filling rate was advanced and steady, especially the grain-filling characteristics of the inferior grain was optimized, more grain was filled. All the advanced characteristics would contribute to a stable and high yield. Thus, to increase rice production, sowing date of mechanically transplanted rice should be advanced to May 26 appropriately in the central part of Jiangsu province, in combination with timely transplanting and scientific cultivation and management practices. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Grain (agricultural product)
Controlled terms:Agricultural machinery - Crops - Cultivation - Filling - Grain growth - Growth (materials) - Plants (botany) - Population statistics
Uncontrolled terms:Characteristics of number for stems and tillers - Comparative studies - Cultivation measures - Grain filling - Japonica hybrid rice - Management practices - Mechanical rice - Sowing date
Classification code:461.9 Biology - 691.2 Materials Handling Methods - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 922.2 Mathematical Statistics - 933.1.2 Crystal Growth - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2015.13.004
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 30>
Accession number:20153101103471
Title:Prediction model on temporal and spatial variation of air temperature in greenhouse and ventilation control measures based on CFD
Authors:Ren, Shougang (1); Yang, Wei (1); Wang, Haoyun (1); Xue, Wei (1); Xu, Huanliang (1); Xiong, Yingjun (1)
Author affiliation:(1) College of Information Science and Technology, Nanjing Agriculture University, Nanjing, China; (2) National Engineering and Technology Center for Information Agriculture, Nanjing, China
Corresponding author:Xiong, Yingjun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:207-214
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Hot and humid environment inside greenhouse in summer is a major threat to crop growth. How to make reasonable control schemes of greenhouse air temperature in summer is the key to improve the greenhouse production efficiency and reduce the energy consumption. In this study, we established a prediction model on temporal and spatial variation of air temperature in greenhouse based on the computational fluid dynamics (CFD) method and meteorology forecast information. The prediction model was adapted to the large multi-span plastic greenhouse in the southern regions of Jiangsu under the natural ventilation and fan-pad cooling system. It can predict the spatial and temporal distribution of greenhouse air temperature under different ventilation cooling conditions. The numerical computation of this prediction model was based theoretically on mass conservation equation, momentum conservation equation and energy conservation equation of fluid. The turbulence transfer was described by the turbulence model, and dealt with the near-wall region using the standard wall function. The DO(discrete ordinates) radiation model was used to simulate the radiation heat transfer of the greenhouse. The meteorology forecast information was mainly used for changing the boundary conditions of prediction model by introducing the influence of outdoor air temperature, the fan-pad cooling system and solar radiation to improve the energy conservation equation of the original model. Among them,the variable temperature boundary conditions under the natural ventilation condition were based on the changes of outdoor air temperature predicted values over time, while the variable temperature boundary conditions under the fan-pad cooling system were based on the changes of air temperature through the evaporative pad over time. Values of air temperature through the evaporative pad were calculated by the evaporative pad cooling model. The solar radiation values were calculated by Solar Ray Tracing Method. Variable external solar radiation boundary conditions can be set by setting each update interval of solar radiation calculation. In order to validate the effectiveness of the prediction model, the spatial and temporal distribution values of air temperature were measured at the key positions in the greenhouse and compared with the simulated data. The results showed that the predicted values matched the measured values. The root mean square error was within 1.2. The maximum relative error was less than 6%. The average relative error was within 4%. The model developed can accurately predict the spatial and temporal variation of indoor air temperature under different ventilation conditions. Experimental results under the different conditions of ventilation showed that the spatial distribution of indoor air temperature exited obvious gradient phenomenon. The air temperature rose with the increase of the height in the vertical direction and the direction of horizontal flow. It was low in the central region of the greenhouse while it was higher around the wall region. According to the results of unsteady-state calculation, the indoor air temperature had the same changing tendency with the outdoor air temperature during the whole prediction period time under the natural ventilation condition. The cooling effect of the fan-pad cooling system was better than the natural ventilation, the air temperature dropped 5 under the fan-pad cooling system, the indoor air temperature can be kept at a lower level by implementing continued fan-pad cooling measure. Based on the simulated results of the model and the target of greenhouse control, the high point of air temperature or the period time for rapid air temperature change were determined in this study. Following by this, appropriate point and length of time to implement different types of ventilation cooling measures were chosen for improving the efficiency of the greenhouse temperature control. This study can provide a reference for the proper implementation of ventilation control strategy and optimizing the layout of the sensors. Compared with the past research, the simulation model established in the paper can predict not only the spatial distribution of indoor air temperature under different ventilation cooling conditions, but also the temporal distribution of indoor air temperature for a long time. Thus, the calculation results of the model were able to provide the basis for greenhouse intelligent control. Further research is needed to optimize the parameter settings of the prediction model to improve the accuracy of computation results. As such, it can help to avoid the lagging response, passive control and inharmonious regulation in conventional control systems by combining the prediction results and intelligent optimization algorithms to reduce the greenhouse energy consumption. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:22
Main heading:Cooling systems
Controlled terms:Air - Algorithms - Atmospheric temperature - Boundary conditions - Computational fluid dynamics - Cooling - Energy conservation - Energy efficiency - Energy utilization - Errors - Fans - Fluid dynamics - Forecasting - Greenhouse effect - Greenhouses - Heat transfer - Mean square error - Meteorology - Optimization - Radiation - Ray tracing - Solar radiation - Spatial distribution - Thermal comfort - Thermoelectric equipment - Turbulence models - Ventilation - Wall function - Weather forecasting
Uncontrolled terms:Computational fluid dynamics methods - Intelligent optimization algorithm - Momentum conservation equations - Pads - Prediction model - Spatial and temporal distribution - Spatial and temporal variation - Temporal and spatial variation
Classification code:402.1 Industrial and Agricultural Buildings - 443 Meteorology - 443.1 Atmospheric Properties - 525.2 Energy Conservation - 525.3 Energy Utilization - 615.4 Thermoelectric Energy - 618.3 Blowers and Fans - 641.2 Heat Transfer - 643 Space Heating, Ventilation and Air Conditioning - 643.5 Ventilation - 657.1 Solar Energy and Phenomena - 731.1 Control Systems - 741.1 Light/Optics - 804 Chemical Products Generally - 921 Mathematics - 931.1 Mechanics
DOI:10.11975/j.issn.1002-6819.2015.13.029
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 31>
Accession number:20153101103477
Title:Particulate phosphorus sources apportionment in small watershed based on sediment fingerprinting
Authors:Zhou, Huiping (1); Chang, Weina (2); Zhang, Longjiang (1)
Author affiliation:(1) Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing, China; (2) School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing, China
Corresponding author:Zhang, Longjiang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:251-256
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Sediment control has attracted more attention in watershed management planning, especially for the transport of contaminants and nutrients (such as phosphorus (P)) by fine sediment. Implementation of specific management solutions for a watershed requires understanding the location and nature of the major sediment sources. Composite fingerprinting techniques have been proved as an effective mean of sediment source apportionment in other countries. However, research using this method is not reported for small watersheds that are relative homogeneity in underlying surface, or have lower sediment load output and more human disturbance. As for nutrients, particulate P adsorbed by fine sediment is the major part of P output in an agricultural watershed. Therefore, successful sediment source apportionment would give an access to P source identification and quantitative apportionment study. The objectives of this paper were to identify the sources of particulate P in a small catchment of the upper Jiuxiang River in Nanjing, and to estimate the relative contributions of the potential sources based on sediment source fingerprinting. A total of 56 surface samples from potential sediment sources were collected, including 20 from woodland, 21 from cultivated land, and 15 from mine areas and roads of transportation. In addition to suspended sediment collection, 17 deposited sediment samples were collected in the mainstream near catchment outlet. Twenty three potential fingerprint properties were selected for laboratory analysis with all samples screened to < 63 μm. Composite fingerprints were acquired by a two-stage statistical fingerprinting procedure and a multivariate mixing model was used to estimate the contributions of potential sediment sources. A goodness of fit model was used to test the performance of the multivariate mixing model. The particulate P source apportionment was then proceeded based on the sediment fingerprinting results and P content information from all potential sources. The apportionment results showed that cultivated land contributed 25.3%-65.2% of the sediment yield and 52.2%-85.8% of the particulate P yield in the studied watershed. The mine and road area contributed 34.8%-74.7% of the sediment yields but only 14.2%-47.7% of the particulate P yield. Less than 0.1% of the sediment or particulate P yield was from woodland. The results showed that cultivated land was a more importance as a particulate P source than as a sediment source due to the high P content of cultivated soils. While the mine and road areas were less important as a particulate P source for their lower P content. As for woodland, relative lower P content and long distance to receiving water made it less important as both sources. Although there still have some significant improvements in the future work, such as prior knowledge and selection of potential sources, optimization for fingerprinting procedure and the consideration of P transform in transport, etc., we concluded that particulate P source apportionment based on sediment fingerprinting could provide a new method to improve the particulate P source apportionment work in the watershed with limited observation data and would be helpful in diffuse source pollution control. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:34
Main heading:Sediments
Controlled terms:Catchments - Highway administration - Land use - Mine transportation - Mixing - Nutrients - Phosphorus - Pollution - Pollution control - Pollution induced corrosion - River pollution - Roads and streets - Runoff - Soil conservation - Soil testing - Surface mine transportation - Suspended sediments - Transportation - Water conservation - Water management - Water pollution - Watersheds
Uncontrolled terms:Agricultural watersheds - Diffuse source pollutions - Fingerprinting techniques - Particulate phosphorus - Relative contribution - Sediment fingerprinting - Small watersheds - Source apportionment
Classification code:403 Urban and Regional Planning and Development - 406.1 Highway Systems - 406.2 Roads and Streets - 431 Air Transportation - 432 Highway Transportation - 432.1 Highway Transportation, General - 433 Railroad Transportation - 434 Waterway Transportation - 444 Water Resources - 444.1 Surface Water - 453 Water Pollution - 454.2 Environmental Impact and Protection - 454.3 Ecology and Ecosystems - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 502 Mines and Quarry Equipment and Operations - 502.1 Mine and Quarry Operations - 802.3 Chemical Operations - 804 Chemical Products Generally
DOI:10.11975/j.issn.1002-6819.2015.13.035
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 32>
Accession number:20153101103475
Title:Effects of cellulose, xylan and lignin content on biomass pyrolysis characteristics and product distribution
Authors:Li, Xiaohua (1); Jiao, Lihua (1); Fan, Yongsheng (1); Chen, Lei (1); Cai, Yixi (1)
Author affiliation:(1) School of Automotive and Traffic Engineering, Jiangsu University, Zhenjiang, China
Corresponding author:Cai, Yixi
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:236-243
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:This paper investigated the effect of cellulose, xylan and lignin content on biomass pyrolysis characteristics and analyzed the interaction rules of the 3 biomass components. The proportions of the 3 components i.e. cellulose, xylan and lignin were reasonably designed, and there were 7 experimental samples according to different quality proportions. The Thermo TGA/DSC 1 was used to analyze the thermo-gravimetric processes of the samples composed of the 3 components. And the pyrolysis characteristics of the cellulose, xylan and lignin were studied. Supposing that the 3 components' thermo-gravimetric processes were isolated with each other, the overall weightlessness process of the mixed samples was attributed to the superposition of every single component's weightlessness. By comparing the experimental and calculated values, the three components' interaction rules when they were mixed and pyrolyzed were analyzed. The Coats integration method was adopted to calculate and analyze the three components' pyrolysis dynamic parameters. At the same time, on the basis of the biomass vacuum pyrolysis liquefaction system, the vacuum pyrolysis experiments of each component and the mixed samples were carried out. Taking biomass as a benchmark, oil and solid production rate and production rate of gas were calculated at the end of the pyrolysis. The production rate of mixed samples' pyrolysis products could be acquired by the superposition of the production rate of single component pyrolysis products according to the mixed proportion. The (GC-MS) Agilent 7890A were adopted to analyze the composition of bio-oil which was obtained through vacuum pyrolysis and liquefaction of 7 samples. By comparing the experimental and calculated value, the influence of those 3 components content on the distribution of pyrolysis product and bio-oil composition was also evaluated. The results indicated that cellulose had good thermal stability, the pyrolysis range was narrow, and its pyrolysis was relatively intense which generated less solid residues, and bio-oil production rate was higher which generated more aromatics, sugars, aldehydes and alcohols. Xylan with a poor thermal stability could generate more aromatics, ketone and acid in bio-oil, and the initial pyrolysis temperature was lower which could generate more gases. Lignin with a poor thermal stability could generate aromatic compounds, the pyrolysis range was narrow and the pyrolysis was relatively mild which generated more solid residues. By analyzing the three components' pyrolysis dynamic parameters, it could be concluded that cellulose had considerable effect on the activation energy and pre-exponential factors while xylan and lignin had greater effects on reaction order. By comparing the experimental and calculated value, it could be concluded that cellulose pyrolysis was beneficial to the reduction of the solid residue while lignin pyrolysis products could promote the decomposing of sugars. Xylan had a negative effect on the cellulose pyrolysis and could benefit the low-temperature pyrolysis of lignin. The co-pyrolysis of xylan and lignin had little influence on the bio-oil composition. Therefore, biomass with high cellulose content could foster the bio-oil yield and a certain amount of lignin could promote the decomposing of cellulose. The results provide a theoretical basis for further improving the yield and quality of the bio-oil. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:36
Main heading:Pyrolysis
Controlled terms:Activation energy - Aromatization - Biofuels - Biomass - Cellulose - Ionization of gases - Ketones - Lignin - Liquefaction - Sugars - Temperature - Thermodynamic stability - Weightlessness - Well stimulation
Uncontrolled terms:Bio oil - Characteristics - Ligin - Low-temperature pyrolysis - Product distributions - Pyrolysis characteristics - Pyrolysis temperature - Xylan
Classification code:461.4 Ergonomics and Human Factors Engineering - 512.2.2 Natural Gas Deposits: Development Operations - 523 Liquid Fuels - 524 Solid Fuels - 525.1 Energy Resources and Renewable Energy Issues - 641.1 Thermodynamics - 801.4 Physical Chemistry - 802.2 Chemical Reactions - 802.3 Chemical Operations - 804.1 Organic Compounds - 815.1.1 Organic Polymers
DOI:10.11975/j.issn.1002-6819.2015.13.033
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 33>
Accession number:20153101103461
Title:Development and validation of critical nitrogen content curve for maize in Guanzhong area
Authors:Li, Zhengpeng (1); Song, Mingdan (1); Feng, Hao (1)
Author affiliation:(1) Institute of Soil and Water Conservation, Northwest A&F University, Yangling, China; (2) Institute of Water and Soil Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, China; (3) Institute of Water Saving Agriculture in Arid Areas of China, Northwest A&F University, Yangling, China
Corresponding author:Feng, Hao
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:135-141
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The nitrogen nutrition index (NNI), derived from the critical N concentration dilution curve, allows the discrimination between crop N status under shortage and surplus N supply. The on-farm survey results shows that nitrogen fertilizer is excessively used in maize production in Guanzhong Plain. However, the famers are lacked of an efficient and simple nitrogen status diagnostic tool to guide the nitrogen application both for increasing crop yield and reducing widespread environmental pollution as well. The objectives of this study were to build and validate the applicability of the critical N concentration dilution curves for summer maize in Guanzhong irrigated area (with the whole growing period of about 105 d) and spring maize in Weibei dryland (with the whole growing period of about 158 d), respectively. The modeling procedure was as following: 1) to collect and analyze 8-site-year (2004-2012) field experiments data under different N application rates in the Guanzhong Plain according; and 2) to determine key points of the critical N concentration curve using data for modeling and to validate the curve using other independent data. Results showed that there existed a negative power function between aboveground maximum biomass (W) and critical N concentration (Nc) (summer maize: Nc=22.5W<sup>-0.27</sup>; spring maize: Nc=25.3W<sup>-0.26</sup>) when aboveground biomass was >1 t/hm<sup>2</sup>. When aboveground biomass was <1 t/hm<sup>2</sup>, the critical value was 23.4 and 32.2 g/kg for summer and spring maize, respectively. The critical N dilution curves were lower than that of spring maize in France and close to that of summer maize in North China Plain. The critical N dilution curves were validated through the NNI defined as the ratio between measured N concentration and critical Nc. The results showed that the nitrogen nutrition index model could be used for accurate diagnosis of maize plant nitrogen status and that plant nitrogen nutrition could be affected by both N application rates and dates, i.e., NNI value would generally increase with increasing N rates under a certain fertilization mode. For example, the average NNI value over summer maize growing season improved from 0.81 to 1.16 as the N rates increased from 0 to 375 kg/hm<sup>2</sup> in Guanzhong irrigated area, while the average NNI value over spring maize growing season increased from 0.53 to 1.22 for N rates from 0 to 400 kg/hm<sup>2</sup> in Weibei rainfed area. Maize would get nutrition imbalance when nitrogen was applied only as the basal fertilizer or with inappropriate fertilizer ratio of basal and topdressing. For example, for summer maize with 300 kg N/hm<sup>2</sup> applied only before planting, the NNI value were 1.18 and 0.91 in vegetative and reproductive growth period, respectively, indicating that extravagant and deficient N uptake in early and later maize-growing season. For spring maize with 70% N applied prior to anthesis date, over-supply of nitrogen was found in vegetative growth stage for all treatments of N≥200 kg/hm<sup>2</sup>. The present critical N dilution curves could be used for the diagnosis of maize nitrogen nutrition, providing a key technical approach to precise N fertilization management in maize production in Guanzhong Plain. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Nitrogen fertilizers
Controlled terms:Biomass - Crops - Diagnosis - Dilution - Ecology - Fertilizers - Nitrogen - Nutrition - Surveys
Uncontrolled terms:Above ground biomass - Critical N concentration dilution curve - Environmental pollutions - Maize growing season - Modeling procedure - Nitrogen nutrition - Reproductive growth - Weibei highlands
Classification code:405.3 Surveying - 454.3 Ecology and Ecosystems - 461.6 Medicine and Pharmacology - 461.7 Health Care - 801 Chemistry - 804 Chemical Products Generally - 821.4 Agricultural Products - 821.5 Agricultural Wastes
DOI:10.11975/j.issn.1002-6819.2015.13.019
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 34>
Accession number:20153101103473
Title:Design and experiment on biochar second-stage cooling system with spiral-flow
Authors:Yao, Zonglu (1); Li, Min (1); Zhao, Lixin (1); Meng, Haibo (1); Cong, Hongbin (1); Hou, Shulin (2)
Author affiliation:(1) Key Laboratory of Energy Resource Utilization from Agricultural Residues, Ministry of Agriculture, Chinese Academy of Agricultural Engineering, Beijing, China; (2) College of Engineering, China Agricultural University, Beijing, China
Corresponding author:Zhao, Lixin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:222-228
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Biomass pyrolysis is an energy converting technology, but during the pyrolysis process, the outlet temperature of biochar is high due to high final pyrolysis temperature. As such biochar continue burning when exposed in air. So only after cooling, biochar can be transported and used. Currently, common practice is that biochar are natural cooled in a sealed container or by sprinkling water directly to biochar after pyrolysis. Both of the methods need a long time, besides, a great deal of residual heat of biochar is wasted during cooling. This leads to the long production cycle, lowly utilization rate of biochar heat in pyrolysis process. So a sealed cooling device is needed to solve the problem. Through this device, the outlet temperature of biochar should be <40-50. Because biomass heat transfer coefficient is low, the cooling process needs more time than other materials, and the new device should be long enough to allow sufficient cooling. As such, a two-stage heat exchange device is needed, using the principle of solid-liquid indirect heat exchange. Such design can ensure that the cooled biochar can be used directly for package, transportation or experiment. In this study, we first examined the details about device structure and size design. Based on analysis and comparison of different structure and biochar sizes, we selected water cooled screw type as the main structure. Biochar was delivered by screw blade in the inner tube with circulating water in out surface of the tube. For such device, the most important part was baffles, it was added between the inner tube and external tube, making circulating water flow in the form of spiral-flow around the inner tube, thus increasing heat transfer time between circulating water and wall surface of inner tube. Based on this, a second-stage biochar cooling system was designed with temperature acquisition terminal and control device, the temperature acquisition terminal was used to monitor the temperature of circulating water and biochar, including two temperature sensors and temperature patrol instrument. The control device regulated water flow and rotation speed of screw axis. We then conducted different cold water flow test,different rotation speeds of screw axis test and different biochar test by use of the system. The application results showed that, the average outlet temperature of biochar was 30, it reached the design requirement. Besides, the application results showed that the temperature difference increased with the rise of cold water flow. The temperature difference of peanut biochar was 272, 242, 222 when rotation speeds of screw axis was 5 r/min, cold water flow was 8, 6.5, 4 m<sup>3</sup>/h. Meanwhile the outlet temperature of peanut biochar was 40, while rotation speed of screw axis was 25 r/min, and cold water flow was 6.5 m<sup>3</sup>/h. In contrast, when rotation speed of screw axis was 5 r/min, the outlet temperature of peanut biochar was 25. In all heat transfer coefficient was different with different biochar. The experiments showed that corn stalk biochar, peanut biochar, corncob biochar overall heat transfer coefficient was 100.6, 85.3, 57.6 W/(m<sup>2</sup>·K), respectively. The cooling process completed smoothly with the cooperation of cooling system and pyrolysis equipment, this system could meet the need of continuous cooling process for various kinds of biochar. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:22
Main heading:Cooling systems
Controlled terms:Biomass - Cooling - Design - Flow of water - Heat exchangers - Heat transfer - Heat transfer coefficients - Hydraulics - Oilseeds - Rotation - Shafts (machine components) - Speed - Thermoelectric equipment - Tubes (components)
Uncontrolled terms:Acquisition terminals - Bio chars - Continuous cooling process - Converting technologies - Heat exchange design - Overall heat transfer coefficient - Pyrolysis temperature - Temperature differences
Classification code:408 Structural Design - 601.2 Machine Components - 615.4 Thermoelectric Energy - 616.1 Heat Exchange Equipment and Components - 631.1.1 Liquid Dynamics - 632.1 Hydraulics - 641.2 Heat Transfer - 821.4 Agricultural Products - 821.5 Agricultural Wastes - 931.1 Mechanics
DOI:10.11975/j.issn.1002-6819.2015.13.031
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 35>
Accession number:20153101103444
Title:Drag reduction characteristics and mechanism of bionic coupling functional surface caused by bionic form and elastic material
Authors:Tian, Limei (1); Ke, Qingpeng (1); Jin, E (1); Li, Ziyuan (1); Wang, Yinci (1); Hu, Yanbing (2)
Author affiliation:(1) Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun, China; (2) College of Biological and Agricultural Engineering, Jilin University, Changchun, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:10-16
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In the present study, a drag reduction on bionic surface originally inspired by the dolphin skin was designed and constructed. Two factors are coupled together with this bionic surface, they are bionic form processed on the basal rigid material and elastic surface material coupling on the bionic form. Such surface was called form/elastic material bionic coupling functional surface (BCFS) in this paper. The BCFS has been used in the impeller surface of centrifugal pump and proved to have the function of drag reduction. However, because of the limitation of existing test equipment, the drag reduction characteristics and mechanism of such BCFS can't be revealed effectively. As such it greatly affects the wide application of the BCFS. Thanks to the gradually maturing fluid-structure coupling simulation technology, it makes the fluid control research by the BCFS possible. The two-way fluid-structure coupling simulation method was used under the ANSYS-Workbench platform to study the characteristics of drag reduction affected by the two coupling factors: elastic modulus of elastic surface material and spacing of basal bionic form. We constructed three different BCFS models whose elastic modulus of surface materials were 2.8×10<sup>4</sup>, 2.8×10<sup>6</sup> and 5×10<sup>6</sup> Pa, respectively under the condition of basal bionic form spacing of 2 mm. Those models were called model 1, model 2 and model 3, and their drag reduction characteristics were investigated. The simulated result showed that the smaller elastic modulus of surface material was the greater the elastic deformation of the surface material would be. So the phenomenon of elastic surface dynamic coupling with basal bionic form was more distinctively, and the fluid control ability of the BCFS became stronger, the total resistance would be reduced. We then constructed another three different BCFS models with bionic form spacing value d of 2, 3 and 4 mm, respectively under the condition of surface material elastic modulus was 5×10<sup>6</sup> Pa. They were called model 4, model 5 and model 6, and their drag reduction characteristics were studied. The simulation result showed that though the bionic form was under the elastic surface material, it had great influence on the drag reduction of BCFS, especially the spacing valued d of bionic form. The average wall shear stress and turbulent kinetic energy dissipation rate of the fluid-structure interface were larger with the increases of the bionic form spacing value d. The larger the spacing value d was, the stronger the wall shear stress would be, so the energy used to overcome the wall shear stress was also increased. This would lead to turbulent kinetic energy dissipation rate rising. Above simulation results indicated that choosing appropriate basal spacing value d would allow a better drag reduction effect. As for the drag reduction mechanism of BCFS, the deformation pushed the fluid-solid actual contact surface downward, the velocity gradient of the fluid boundary layer decreased, resulting in frictional force reduction. In addition, the elastic deformation absorbed some of the energy, effectively reducing the turbulent kinetic energy, avoiding excessive exchange and energy loss at the fluid-solid interface. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Bionics
Controlled terms:Atmospheric thermodynamics - Biomimetics - Boundary layer flow - Boundary layers - Couplings - Drag - Drag reduction - Elastic deformation - Elastic moduli - Energy dissipation - Equipment testing - Fluid structure interaction - Kinetic energy - Kinetics - Shear stress
Uncontrolled terms:Characteristics and mechanisms - Drag reduction mechanism - Fluid structure couplings - Fluid-solid coupling - Fluid-solid interfaces - Fluid-structure interfaces - Functional surfaces - Turbulent kinetic energy
Classification code:421 Strength of Building Materials; Mechanical Properties - 443.1 Atmospheric Properties - 461.9 Biology - 525.4 Energy Losses (industrial and residential) - 602 Mechanical Drives and Transmissions - 651.1 Aerodynamics, General - 731.1 Control Systems - 931 Classical Physics; Quantum Theory; Relativity - 931.1 Mechanics - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments
DOI:10.11975/j.issn.1002-6819.2015.13.002
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 36>
Accession number:20153101103455
Title:Yield reduction analysis and determination of drainage index in cotton under waterlogging followed by submergence
Authors:Qian, Long (1); Wang, Xiugui (1); Luo, Wenbing (2); Jia, Wen (1); Wu, Lin (1)
Author affiliation:(1) State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, China; (2) Yangtze River Scientific Research Institute, Wuhan, China
Corresponding author:Wang, Xiugui
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:89-97
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to study the effects of submergence and waterlogging on cotton yield, submergence and waterlogging experiments in lysimeters of three stress forms with different degrees and different growth stages were conducted in the Irrigation and Drainage Experiments Station of Wuhan University from 2008 to 2011. Three stress forms with different degrees included submergence for 1-3 days, waterlogging for 3-8 days, and submergence for 1-5 days followed by waterlogging for 3-8 days. The experiment was performed in 3 cotton growth stages: budding, flowering and boll opening stage. In this study, 2 types of drainage indexes including sum of flood depth and excess soil water under submergence (SWFDH), sum of excess soil water under waterlogging ( SEW' 30), sum of flood depth under submergence (SFW) and sum of excess soil water under submergence and waterlogging (SEW<inf>30</inf>), were used to quantify stress degrees of submergence and waterlogging. The effects of submergence and waterlogging on cotton yield were quantified by yield reduction rate factors (YR) of each stress forms, and thus weight factor of waterlogging was determined. The responses of three growth stages to submergence followed by waterlogging were quantified by YR of each growth stages, and thus generalizing yield reduction rate factors (NYR) of three growth stages were estimated. Based on NYR and weight factor of waterlogging, a new drainage index cumulative sum of flood depth and excess soil water (CSFEW<inf>30</inf>) was put forward. The results showed that the drainage indexes, SWFDH and SEW' 30, could well describe the relationship between the degree of submergence and waterlogging with yield reduction more stably than SFW and SEW<inf>30</inf> in different years. The yield reduction rate factors of submergence and waterlogging were 0.266%/(cm·d) and 0.202%/(cm·d), respectively. Yield reduction under waterlogging was 0.759 times that under submergence. Without considering the effect of submergence on yield reduction of following waterlogging, the calculated yield reduction would be 43.1% higher than the actual yield reduction. And when the effect was taken into account, the yield reduction of waterlogging was 0.293 times as much as that of submergence. Flowering stage was the most insensitive growth stage for cotton under submergence and waterlogging, followed by budding stage and boll opening stage. Yield reduction rate factors of three growth stages are 0.114%/(cm·d), 0.150%/(cm·d) and 0.033%/(cm·d), respectively, and thus the proportion of yield reduction in the three stages was 0.760:1:0.220. Without considering the effects of submergence and waterlogging in former growth stages on yield reduction in latter stages, the calculated yield reduction would be 8.8% higher than the actual yield reduction. The effects of submergence and waterlogging on yield in former stages would extend to latter stages slightly. Drainage index CSFEW<inf>30</inf> was of highly significant (R<sup>2</sup>=0.629, n=15, P<0.001) linear relationship with yield reduction, which provides evidence for the determination of drainage standard of cotton under the submergence and waterlogging control. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Underwater soils
Controlled terms:Cotton - Drainage - Floods - Soil moisture - Soils - Stresses
Uncontrolled terms:Different growth stages - Drainage experiments - Drainage indices - Growth stages - Index - Linear relationships - Submergence - Waterlogging
Classification code:401 Bridges and Tunnels - 406 Highway Engineering - 421 Strength of Building Materials; Mechanical Properties - 442 Flood Control; Land Reclamation - 442.1 Flood Control - 483.1 Soils and Soil Mechanics - 502 Mines and Quarry Equipment and Operations - 819.1 Natural Fibers
DOI:10.11975/j.issn.1002-6819.2015.13.013
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 37>
Accession number:20153101103448
Title:New corridor edge detection and navigation for greenhouse mobile robots based on laser scanner
Authors:Jia, Shiwei (1); Li, Junmin (1); Qiu, Quan (2); Tang, Huijuan (1)
Author affiliation:(1) Mechanical Engineering and Automation College, Xihua University, Chengdu, China; (2) Beijing Academy of Agriculture and Forestry Sciences, Beijing, China; (3) Beijing Research Center of Intelligent Equipment for Agriculture, Beijing, China
Corresponding author:Qiu, Quan
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:39-45
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:This paper proposes a new corridor edge detection and navigation algorithm based on laser scanner data for greenhouse mobile robots. The type of laser scanner is SICK LMS-30206, and the data in each group include 361 distance values in a single scan. All the values will queue in an angle-ascending order, with 0 degree as the start and 180 degree as the stop. For the corridor edge detection task, the algorithm will intensify the fluctuating features of the range values in the same scan by background removing. Then the modified scan will be divided into 24 equal subsectors. The mean square error of range value of each subsector will be computed and compared. The subsector with the minimum mean square error of range value will be taken as the corridor candidate. And bi-direction expending search will be launched for the corridor candidate. The expending search will stop at the point whose adjacent range value difference is larger than a predefined threshold. When the search stops, the corresponding laser beam serial numbers of the corridor edges will be found. As other objects may be mistaken as corridor when they are located in the neighborhood area of corridor and share similar range values with corridor scan points, a pseudo-corridor removing strategy is also presented. With the help of a benchmark corridor width, the pseudo-corridor scan points can be removed. The corridor edges can be used to generate speed control orders for the mobile robot. A new developed front-wheel-driven mobile robot called Walle is employed as the experimental platform. Walle has 4 wheels. The 2 front wheels are equipped with servo motors. The 2 rear wheels are universal. It can change its heading direction in a differential walking mode. In the navigation process, the center of the scan line in the corridor is chosen as the navigation goal for each speed control sampling period, and the speed differential between the 2 driving wheels is the main control parameter. By analyzing the geometrical and kinematical relationships, a transfer function between the expected steering error and the speed differential can be built. Then the speed differential can be induced from the corridor edge information based on the transfer function. Finally, speed-altering control orders can be generated according to the speed differential. Here the new algorithm chooses to speed up one wheel and slow down the other for obtaining the expected speed differential. Experiments are conducted on Walle under different environmental conditions, including the indoor corridor, the outdoor curve routine, and the inner-greenhouse corridor. The robot can navigate itself in the indoor corridor scene with a mean horizontal error of 1.2707 cm and a mean square error of 2.6772 when following the corridor center line. Also, Walle can navigate itself in the outdoor curve routine and the inner-greenhouse corridor successfully. Because Walle lacks the self-localization sensors on board, the real-time position values can't be obtained and recorded for the outdoor curve routine and the inner-greenhouse corridor cases. Two website addresses of the experimental videos are given as remedial measure. The feasibility of the new algorithm is verified through the experiments mentioned above. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:14
Main heading:Robots
Controlled terms:Algorithms - Edge detection - Errors - Greenhouses - Laser applications - Laser beams - Mean square error - Mobile robots - Navigation - Scanning - Speed - Speed control - Transfer functions - Wheels
Uncontrolled terms:Background removing - Corridor - Environmental conditions - Experimental platform - Laser scanner - Main control parameters - Minimum mean square errors - Navigation algorithms
Classification code:402.1 Industrial and Agricultural Buildings - 601.2 Machine Components - 716 Telecommunication; Radar, Radio and Television - 716.3 Radio Systems and Equipment - 723 Computer Software, Data Handling and Applications - 731 Automatic Control Principles and Applications - 741.3 Optical Devices and Systems - 744.8 Laser Beam Interactions - 744.9 Laser Applications - 921 Mathematics - 931.1 Mechanics
DOI:10.11975/j.issn.1002-6819.2015.13.006
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 38>
Accession number:20153101103479
Title:Rural settlements spatial pattern evolution and zoning district based on spatial autocorrelation
Authors:Jiang, Guanghui (1); He, Xin (1); Ma, Wenqiu (1); Wang, Mingzhu (1); Zhang, Ruijuan (1)
Author affiliation:(1) State Key Laboratory of Earth Surface Process and Resource Ecology, Beijing Normal University, Beijing, China; (2) College of Resources Science and Technology, Beijing Normal University, Beijing, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:265-273
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Research on rural settlements spatial pattern and their evolution helps to reveal the interaction between human and land in different development stages and different areas. It provides theoretical basis for rational land use planning and rural settlement classification management. Rural settlements' morphology reflects both the natural geographical and social economic development condition. According to our research, rural settlements' morphology characteristic has significant correlation with topography, population and living condition of people, etc. Therefore, attributes of rural settlements themselves, namely their displayed morphology, can be used to replace the commonly-used index for the zoning of rural settlements. Meanwhile, spatial autocorrelation method can measure the morphological characteristics of spatial agglomeration pattern which provides the foundation for concentrated continuous rural settlements zoning. Taking Pinggu District, Beijing City as an example, the paper conducted a study on the spatial pattern and zoning of rural settlements. The paper extracted rural settlements in 1993, 2003 and 2011 in Pinggu District. Spatial autocorrelation was applied to depict the spatial pattern of rural settlements morphology characteristics, including the size, shape and distribution. And then the relationship was analyzed between size, shape and distribution characteristics of overlapped regions. On the basis of the spatial autocorrelation result and the overlap region analysis, we put forward the comprehensive management zoning of rural settlements. The main results of the study were as follows: Firstly, size, shape and distribution showed significant spatial autocorrelation. Positive autocorrelation types took the form of the group, whereas negative ones scattered. Secondly, obvious differences existed in agglomeration characters between the plain and the hilly mountainous areas. Rural settlements demonstrated large size, regular shape and concentrated distribution in plain, whereas rural settlements in hilly mountainous region were contrary to those in plain. Thirdly, size, shape and distribution of agglomeration region had a certain space consistency. Positive autocorrelation of these features had an overlap in hilly mountainous region and in plain, and the overlap degree in plain was relatively low compared to that in hilly mountainous region. The spatial pattern of rural settlements showed space consistency mainly because of terrain and landform. Rural settlements in hilly mountainous region embodied high space consistency which contained low-low agglomeration areas of size feature, high-high agglomeration areas of shape feature and high-high agglomeration areas of distribution feature. Rural settlements in plain embodied relatively low space consistency. The main reason for the phenomenon was the urbanization and economic development. Fourthly, zoning in Pinggu District was based on spatial pattern characteristics, regional planning and advices from experts who were familiar with Pinggu District. The rural settlements were mainly divided into 5 parts, namely the industry land expansion zones, pilot farm operation zones, differentiate administrative zones, distinctive village development zones and relocation and regulation village zones. Industry land expansion area in plains should pay attention to enhance land use efficiency and improve the rural settlements' land use integrated benefits. As for rural settlements at the junction of plains and hilly areas, it should manage differently and promote integrated management mode. Agricultural demonstration areas should adjust the structure in order to improve production and living conditions. What's more, the development of tertiary industry should be encouraged in the villages. Moving and merging village areas and distinctive village development zones should realize the integration development and improve the infrastructure construction. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Rural areas
Controlled terms:Agglomeration - Autocorrelation - Economic and social effects - Economics - Land use - Landforms - Morphology - Regional planning - Zoning
Uncontrolled terms:Classification managements - Distribution characteristics - Infrastructure construction - Morphological characteristic - Rural settlement - Spatial agglomeration patterns - Spatial autocorrelation methods - Spatial patterns
Classification code:403 Urban and Regional Planning and Development - 403.2 Regional Planning and Development - 481.1 Geology - 802.3 Chemical Operations - 921 Mathematics - 922 Statistical Methods - 951 Materials Science - 971 Social Sciences
DOI:10.11975/j.issn.1002-6819.2015.13.037
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 39>
Accession number:20153101103447
Title:Kinematics analysis and experiment of multifunctional agricultural robot in greenhouse with three arms
Authors:Quan, Longzhe (1); Zhang, Dongdong (1); Zha, Shaohui (1); Xi, Dejun (1); Wang, Hao (1)
Author affiliation:(1) College of Engineering, Northeast Agricultural University, Harbin, China
Corresponding author:Zhang, Dongdong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:32-38
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In Greenhouses, the management of fruits and vegetable production involves many tasks, such as picking, spraying, cutting and so on. However, the agricultural robots currently available mainly focus on one specific task. This research focused on a new multifunctional agricultural robot with three arms. Each of its robotic arms has its own function for a different end use. The robot not only can complete one task by collaboration of two different robotic arms but also can fulfill spraying, cutting and picking tasks in the same area. So by using such robot, output productivity can be improved effectively and the cost would be reduced. The robot comprises caterpillar chassis, height-adjustable torso, mechanical structure with three arms, machine-vision system and control system. When at the state of working, the robot uses its machine-vision system to recognize targets. At the moment when targets are found, the robot adjusts its position in order to do tasks correspondingly. Setting up kinematics model of the agricultural robot is the precondition of realizing the system multi-functions. In this paper, we set up the link coordinate system of agricultural robot based on D-H approach. Homogeneous transforming matrixes of adjacent link were established according to the linkage parameters and joint variables. Kinematics equations of visual system, cutting end effector, picking end effector and spraying end effector were deducted and solved, respectively. So the relationship between the position and posture of end effects and linkage parameters and joint variables were determined. The closed-form inverse kinematics was presented by algebraic method and the value of joint variables was calculated according to the certain position and posture of end effects. Kinematics experiments were carried out to verify the correctness of kinematics algorithm and accuracy in application. Matlab software was used to help the calculation of the enveloping space of end effects in the mode of picking and spraying. A series of 12 points already known were picked up as test samples. In the test platform, end effect was moved to location one by one in the given order by driving motors and real coordinate data was collected. The results showed that the robot could carry out specific action under the guidance of kinematics model and the maximum error was only 8 mm. These researches lay foundation for further study of dynamic performance, trajectory planning and accurate motion control of multifunctional agricultural robot. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:19
Main heading:Robot programming
Controlled terms:Agricultural machinery - Agriculture - Algebra - Computer vision - End effectors - Greenhouses - Inverse kinematics - Inverse problems - Kinematics - Machinery - MATLAB - Robotic arms - Robotics - Robots
Uncontrolled terms:Closed-form inverse kinematics - D-H method - Fruits and vegetables - Kinematics analysis - Kinematics equation - Kinematics modeling - Machine vision systems - Mechanical structures
Classification code:601 Mechanical Design - 731.5 Robotics - 731.6 Robot Applications - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921 Mathematics - 921.1 Algebra - 931.1 Mechanics
DOI:10.11975/j.issn.1002-6819.2015.13.005
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 40>
Accession number:20153101103472
Title:Comparison of flat photo-bioreactors for micro-algae culture based on CFD numerical simulation
Authors:Qi, Xiangming (1); Cui, Hailong (1)
Author affiliation:(1) College of Food Science and Engineering, Ocean University of China, Qingdao, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:215-221
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Algae as potential resources, has attracted increasing interest and attention from many fields such as energy, medicament, food, feed, and environment. However design and optimization of photo-bioreactor for algae production remains a bottleneck in the development of microalgae culturing industry. Recently, flat photo-bioreactor is improved by changing the double-flat into multistage structure. In this study, in order to further increase mass transfer and mixing properties of microalgae photo-bioreactor, a multistage intake structure was fixed into this multistage flat photo-bioreactor. Moreover, for the purpose of exploring more mass transfer and mixing details of the three photo-bioreactors, the ordinary double-flat photo-bioreactor, multistage flat photo-bioreactor, and multistage intake photo-bioreactor were constructed physically and numerically, and their computational fluids dynamics (CFD) simulations were carried out. Gas holdups and mass transfer coefficients were measured in physical multistage intake photo-bioreactor and compared with simulated results to verify reliability of the applied CFD simulating method. Then speed cloud, mean liquid velocity, dead zone, turbulent kinetic energy, turbulent kinetic energy dissipation rate, gas holdup, mass transfer coefficient were used to analyze mass transfer and mixing performances of the three reactors. Results of gas holdup and mass transfer coefficient showed that the CFD simulation agreed well with experimental results, which indicated that the CFD simulation method in this work was reliable. Results of speed clouds showed that the multistage-intake structure caused significant emergence of circulating current in every stage, which tended to form in the multistage flat reactor but failed finally. Liquid velocities of these currents increased from bottom to top of the multistage-intake reactor. Compared with the other two photo-bioreactors, the currents in the multistage-intake led to increase in indexes (e.g. mean liquid velocity, dead zone, turbulent kinetic energy, turbulent kinetic energy dissipation rate, gas holdup, and mass transfer coefficient) of the multistage-intake photo-bioreactor. In point of mixing properties, differences of some indexes (including mean liquid velocity, turbulent kinetic energy, and turbulent kinetic energy dissipation rate) between the multistage intake reactor and the other two reactors became larger when aeration rate (volume of air intake per minutes over the volume of a container) was greater than 0.4. Meanwhile, difference of dead zone ratio was the highest when aeration rate was 0.6. At the point of mass transfer properties, differences of gas holdups between multistage intake reactor and the other two reactors increased when the aeration rate increased to 0.8 and decreased after 0.8. At 0.8, the gas holdup of the multistage intake photo-bioreactor was 52.63% and 39.11% higher than those of ordinary photo-bioreactor and multistage flat photo-bioreactor, respectively. As the most direct index, mass transfer coefficient of the multistage-intake photo-bioreactor was increased by 36.16% and 11.27% comparing to ordinary photo-bioreactor and multistage flat photo-bioreactor, respectively. All the above results indicated that, multistage flat photo-bioreactor performed better than double-flat photo-bioreactor. However the newly-built multistage intake photo-bioreactor gave the best performance in both mixing and mass transfer properties among the three types of reactors, especially for the aeration rate ranging from 0.4 to 0.8, the suitable aeration rate for microalgae culturing. The multistage intake structure put forward in this paper is of great assistance to design and establishing optimal flat photo-bioreactor. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Computational fluid dynamics
Controlled terms:Air - Air intakes - Algae - Bioconversion - Bioreactors - Energy dissipation - Fluids - Gases - Ionization of gases - Kinetic energy - Kinetics - Liquids - Mass transfer - Microorganisms - Mixing - Multiphase flow - Non Newtonian liquids - Structural properties - Velocity
Uncontrolled terms:CFD numerical simulations - Circulating current - Computational fluids dynamics - Design and optimization - Multistage intake - Multistage structure - Potential resources - Turbulent kinetic energy
Classification code:408 Structural Design - 461.2 Biological Materials and Tissue Engineering - 461.9 Biology - 525.4 Energy Losses (industrial and residential) - 631.1 Fluid Flow, General - 641.3 Mass Transfer - 802 Chemical Apparatus and Plants; Unit Operations; Unit Processes - 804 Chemical Products Generally - 931.1 Mechanics - 931.2 Physical Properties of Gases, Liquids and Solids - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2015.13.030
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 41>
Accession number:20153101103478
Title:Infrastructure of standard system for land use engineering in China
Authors:Liu, Guangsheng (1); Wang, Hongmei (1); Hu, Yueming (2); Cheng, Yingxuan (1)
Author affiliation:(1) College of Public Management, South China Agricultural University, Guangzhou, China; (2) College of Natural Resources and Environment, South China Agricultural University, Guangzhou, China; (3) Guangdong Province Key Laboratory of Land Use and Consolidation, Guangzhou, China
Corresponding author:Wang, Hongmei
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:257-264
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Land use contradictions between economic development, food security and ecological protection are becoming more and more prominent with the rapid development of urbanization and industrialization in China. Land use engineering is an important support to alleviate land use contradictions. Chinese policy-makers have recognized the important role of land-use engineering on land use contradictions. The central government budget invested in land use engineering increases gradually. Standardization is of great significance to promote land use engineering practice. However, standardization level of land use engineering is still very low. The number of standards is rare. There are only 26 standards related to land use engineering. It is far from the needs of land-use engineering practices. Land use engineering standard system, the blueprint for constructing and revising standards, has not yet been built. For this reason, land use engineering and its standard system connotation were initially expounded in this paper according to specific characteristics of land use engineering and standard system. Then, questionnaires and semi-structured interviews were employed to collect the current situation and the demand of the land use engineering standard, and the suggestion of standard system. Beijing, Guangzhou, Wuhan, Xining, Wuxi, Harbin, Sichuan were selected to implement the investigation. Numerous proposals on standard system and current standards were collected from different land experts and front-line land workers. The characteristics of the current situation and the demand of the land use engineering standard were analyzed for the construction of the standard system. Based on the basic principles for building land use engineering standard system and the work flow drawn out from a large number of land use engineering practices in different regions, Systems Engineering proposed by Hall was applied to put forward preliminary framework of land use engineering standard system from 3 dimensions, including specialized categories (comprehensive renovation, land development, land consolidation, land reclamation and land protection), specialized sequences (integration, investigation, appraisal, plan, construction, engineering and technology, materials and equipment, and management) and standard levels (basis standards, common standards, specialized standards). Specialized categories are divided by land use target and objects. Comprehensive renovation is systems engineering containing the remediation of paddy, water ditch, road, forest and village; land development changes the structures of land function bodies; land consolidation adjusts the structures of land function bodies; land reclamation recovers land function bodies; and land protection protects land function bodies. Specialized sequences are the independent technology processes or technical methods that are significantly different from other professional activities, which contain 5 first-stage classifications and 35 second-stage classifications. Standard levels are distinguished by the scope of application. Generally speaking, the number of basis standards is the least and specialized standards are the most. The hierarchical structure of the standard reflects the inner link between the standards. The upper standards limit the lower standards. Land use engineering standard system is different from the existing land resources standard system developed by China's Ministry of Land and Resources in objects, purposes and methods. Land use engineering standard system includes both existing standards and demand standards. In this paper, land use engineering standard system table including 49 demand standards is constructed and it may provide reference to make the long-term plan or annual plan for land use engineering standards. The established standard system is significant to promote standardization of land use engineering. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:11
Main heading:Standards
Controlled terms:Budget control - Construction equipment - Economics - Food supply - Land reclamation - Land use - Standardization - Surveys - Systems engineering
Uncontrolled terms:Ecological protection - Economic development - Engineering and technology - Engineering practices - Engineering standards - Hierarchical structures - Professional activities - Semi structured interviews
Classification code:404.2 Civil Defense - 405.1 Construction Equipment - 405.3 Surveying - 442.2 Land Reclamation - 902.2 Codes and Standards - 911 Cost and Value Engineering; Industrial Economics - 912 Industrial Engineering and Management - 961 Systems Science - 971 Social Sciences
DOI:10.11975/j.issn.1002-6819.2015.13.036
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 42>
Accession number:20153101103456
Title:Response of cotton to interaction of waterlogging and high temperature during flowering and boll-forming stage and determination of drainage index
Authors:Wu, Qixia (1); Zhu, Jianqiang (1); Yang, Wei (2); Cheng, Lunguo (3); Yan, Jun (2)
Author affiliation:(1) Engineering Research Center of Ecology and Agricultural Use of Wetland, Ministry of Education, Yangtze University, Jingzhou, China; (2) Agricultural College of Yangtze University, Jingzhou, China; (3) Irrigation and Drainage Experimental Station of the Four Lake Engineering Management Bureau, Jingzhou, China
Corresponding author:Zhu, Jianqiang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:98-104
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Hubei plain area is characterized by plenty of heavy precipitation and high temperature during the flowering and boll-forming stage of cotton, which may result in frequent occurrence of waterlogging and hot damage in cotton field. Waterlogging and high temperature may interactively damage cotton growth and yield. This study aimed to investigate the response of cotton growth and yield to interaction of waterlogging and high temperature condition. In order to achieve the objectives, tube-shaped concrete facilities were used for irrigation and drainage adjustment. Cotton was planted in the facility in 2013 and 2014. The experiments were carried out in Irrigation and Drainage Experimental Station of the Four Lake Engineering Management Bureau, Jingzhou, China (112°31'E, 30°21'N).Waterlogging, high temperature period and interaction stress were designed. The interaction of waterlogging and high temperature was conducted in the lowering and boll-forming stage of cotton. The soil moisture in the waterlogging treatment was kept at 90% water holding capacity above. Meanwhile, the facility for cotton cultivation in soil with moisture kept at 70%-80% water holding capacity was used as a control. After treatments, the groundwater table was lowered to 80 cm below. The plant height (PH), number of fruit branch (NFB), chlorophyll content (Chla, Chlb, Chl(a+b)), malonaldehyde content (MDA), soluble sugar (SS) and soluble protein(SP) were measured. The yield and its component of cotton were determined. The results showed that:1) In normal temperature or high temperature, the cotton plant became obviously dwarf, and SS and SP content in the fourth leaf from the top increased significantly with a minimum of 3 d waterlogging (P<0.05). In normal temperature, the numbers of fruit branch decreased significantly (P<0.05) and MDA content in the forth leaf from the top increased with a minimum of 6 d waterlogging, but in high temperature it increased with a minimum of 3 d waterlogging. In normal temperature,the content of Chla in the forth leaf from the top decreased significantly (P<0.05) with a minimum of 12d waterlogging, while in high temperature it decreased with a minimum of 15d waterlogging. Cotton suffering from waterlogging, hot damage, and their interactive effects during flowering and boll-forming stage had a severe yield reduction with influence degree ordered as interactive effects>waterlogging>high temperature. Whether in the high temperature condition or normal temperature, the seed cotton yield was significantly (P<0.05) lower than control when cotton suffered from 3 days of waterlogging. The reason of yield reduction was that severe waterlogging stress decreased boll numbers and weight per boll. Assuming the seed cotton yield decreasing by 20% as the drainage waterlogging standard and waterlogging with 4 days of high temperature appearing in flowering and boll-forming stage of cotton, the maximum waterlogged duration should be 3.4 days, before which the surface water must be drained in order to keep cotton yield and groundwater table should be lower to 80 cm below within 3 days after drainage. The results are helpful in relieving climatic disaster in cotton production. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:23
Main heading:High temperature engineering
Controlled terms:Cotton - Drainage - Fruits - Groundwater - Irrigation - Moisture - Soil moisture - Stages - Stresses - Surface waters
Uncontrolled terms:Engineering management - Experimental stations - High temperature - High temperature condition - Interaction - Water holding capacity - Waterlogging - Yield
Classification code:401 Bridges and Tunnels - 402.2 Public Buildings - 406 Highway Engineering - 421 Strength of Building Materials; Mechanical Properties - 442 Flood Control; Land Reclamation - 444.1 Surface Water - 444.2 Groundwater - 483.1 Soils and Soil Mechanics - 502 Mines and Quarry Equipment and Operations - 801.4 Physical Chemistry - 821.3 Agricultural Methods - 821.4 Agricultural Products - 901 Engineering Profession
DOI:10.11975/j.issn.1002-6819.2015.13.014
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
<RECORD 43>
Accession number:20153101103466
Title:Simulation on crops spatial competition based on FCS and EPIC models under future scenarios
Authors:He, Yingbin (1); Gao, Mingjie (1); Zhou, Zhenya (1); Zhang, Qing (1); Wei, Wenshan (1); Chen, Xueyuan (1); Liu, Yang (1)
Author affiliation:(1) Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China; (2) The Management School of Tianjin Polytechnic University, Tianjin, China
Corresponding author:Gao, Mingjie
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:13
Issue date:July 1, 2015
Publication year:2015
Pages:171-177
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In this paper, the Northeast China including the 3 provinces of Heilongjiang, Liaoning and Jilin was regarded as study area where maize, rice and soybean were main food crops. Simulation of spatial competition of the 3 crops under 4 future combined scenarios of IPCC CO<inf>2</inf> emission and socio-economic development (urbanization rate and governmental purchasing price for food crops) was conducted for the year of 2030 by application of the FCS (farmer crop selection) model () and EPIC (environmental policy integrated climate) model. The 4 final scenarios were A2C1D1, A2C1D2, B2C2D1 and B2C2D2. A2C1D1 represented a combination scenario by IPCC A2 option, farmers having no income when going to city to do temporary work and prices for food crop purchased by government doubling. A2C1D2 meant a combination scenario by IPCC A2 option, farmers having no income when going to city to do temporary work and prices for food crop purchased by government quadrupling. B2C2D1 was a combination scenario by IPCC B2 option, farmers having income when going to city to do temporary work and prices for food crop purchased by government doubling. B2C2D2 denoted a combination scenario by IPCC B2 option, farmers having income when going to city to do temporary work and prices for food crop purchased by government quadrupling. In comparison with simulation results in 2009, the conclusions were: 1) For the first scenario of A2C1D1, percentage of maize acreage to total arable land decreased to 77.36% from 82.3%, and meanwhile there was an increase from 7.7% and 10% to 8.93% and 13.71% for soybean and paddy rice, respectively; spatially, maize acreage declined in the fringe areas between the Lesser Xing'an Mountain and the Haerbin Plain, but in the Liaohe Plain acreages of soybean and rice went up respectively. 2) For the second scenario of A2C1D2, percentage of maize acreage to total arable land decreased to 75.56% and meanwhile that of soybean and paddy rice increased to 9.52% and 14.92%, respectively; spatially the change was very similar to that of the scenario of A2C1D1. 3) For the third scenario of B2C2D1, due to a little bit higher urbanization rate than present and present purchasing price by government doubling, percentage of maize acreage to total arable land increased to 84.16%, and meanwhile soybean and paddy rice increased to 9.52% and 14.92%, respectively; maize acreage rose in the fringe areas between the Lesser Xing'an Mountain and the Haerbin Plain, while in the Liaohe Plain acreages of soybean and rice went down respectively, which was contrary to that of the A2C1D1scenario. 4) For the fourth scenario of IPCC B2C2D2, due to a little bit higher urbanization rate than present and present purchasing price by government quadrupling, percentage of maize acreage to total food crops acreage decreased to 80.06%, and meanwhile soybean and paddy rice increased to 9.01% and 10.93%, respectively. There was not obvious change in space. Since 2030 is not far from present, there are not very dramatic changes of food crops in space for all the 4 scenarios. We also don't consider extreme events' effect on spatial competition of food crops because cognition and judge of farmers will not be influenced by that. In terms of present practical situation in China, we deduce the scenarios of B2C2D1 and B2C2D2 maybe more accord with reality. Moreover, B2C2D2 will be more beneficial to optimizing agricultural layout. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Crops
Controlled terms:Agriculture - Climate models - Costs - Economic and social effects - Economics - Environmental protection - Land use - Landforms - Models - Remote sensing - Sales
Uncontrolled terms:Crop selections - Environmental policy - EPIC model - Food crops - Future scenario - Northeast China - Socio-economic development - Spatial competition
Classification code:403 Urban and Regional Planning and Development - 443 Meteorology - 454.2 Environmental Impact and Protection - 481.1 Geology - 731.1 Control Systems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4 Agricultural Products - 902.1 Engineering Graphics - 911 Cost and Value Engineering; Industrial Economics - 911.4 Marketing - 921 Mathematics - 971 Social Sciences
DOI:10.11975/j.issn.1002-6819.2015.13.024
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.Compendex references:YES
期刊信息
- 主管单位 中国科学技术协会
- 主办单位 中国农业工程学会
- 主编 朱明
- 总编/社长 王应宽
- 地址 北京朝阳区麦子店街41号
- 邮编 100125
- 电话 010－59197078/7077/7076
- 邮箱 tcsae@tcsae.org
微信公众号
二维码
友情链接
- Bioresource Technology
- Industrial Crops and Products
- Biomass & Bioenergy
- Biosystems Engineering
- Aquacultural Engineering
- International Journal of Agricultural and Biological Engineering
- Journal of Irrigation and Drainage Engineering
- Paddy and Water Environment
- Journal of Agricultural Engineering
- Transactions of the ASABE
- Revista Brasileira de Engenharia Agricola e Ambiental
- Applied Engineering in Agriculture
- Engenharia Agricola
- AMA-Agricultural Mechanization in Asia Africa and Latin America
- 中华人民共和国农业农村部-MARA
- 中国科学技术协会CAST
- 国家新闻出版署
- 中华人民共和国科学技术部
- 国家自然科学基金委员会
- U.S. DEPARTMENT OF AGRICULTURE
- CIGR
- ASABE
- EurAgEng-European Society for Agricultural Engineers
- American Society of Agronomy
- Crop Science Society of America
- Soil Science Society of America
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- CNKI
- 万方数据
- 维普