<RECORD 1>
Accession number:20181605031872
Title:Simulation of evapotranspiration of corn under mulched drip irrigation based on SIMDual_Kc model in Tongliao area of Inner Mongolia
Authors:Li, Ruiping (1); Zhao, Jingdan (1); Shi, Haibin (1); Wang, Ning (2); Qi, Yinglong (1); Feng, Yayang (1); Jia, Qiong (1)
Author affiliation:(1) College of Water Conservancy and Civil Engineering, Inner Mongolia Agricultural University, Hohhot; 010018, China; (2) Institute of Water Conservancy Science of Inner Mongolia Municipality, Hohhot; 010051, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:127-134
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In recent years, the mulched drip irrigation due to its efficient irrigation has been promoted in Inner Mongolia. However, few studies have focused on this area. In this study, we investigated the difference soil evaporation under the film mulching and bare land in order to clarify the change law of evaporation of corn and explore the mechanism of water saving and yield increase of corn under mulched drip irrigation in Northeast of Inner Mongolia. The SIMDual_Kc model was used to simulate the change of crop coefficient. And the crop coefficient was used for soil evaporation calculation. The model was calibrated by the results from the filed experiment. The field experiment was carried out in 2014 and 2015. A total of 3 treatments including low, mid and high water treatments were designed based on field capacity. The corn was planted under the mulching and bare land. The soil moisture was determined by TDR and the soil evaporation was measured by standard and self-made lysimeters. Meanwhile, the corn height and leaf area were determined during the growing period of corn. The model calibration and validation results showed that the simulated soil moisture agreed well with the measured values. The R<sup>2</sup>was 0.85-0.91 and the root mean square error was 1.0% and below. The soil moisture under the film mulching was lower than that of bare land after rainfall. It indicated that the film could prevent rainfall into soil. The simulated soil moisture of film mulching was higher than that of bare land, suggesting that the film could protect soil moisture from evaporation. Based on the simulation, the basal crop coefficient was 0.15, 1 and 0.4 under the bare land and 0.15, 1.05 and 0.4 under the film mulching in the early, middle and late growth stage of corn. In the early stage, the basal crop coefficient and its adjustment was similar for the treatment of bare land since the root was shallow and continuous rainfall. In the middle stage, the transpiration dominated and the soil evaporation coefficient was the lowest. In the later stage, the evaporation coefficient was slightly increased again. The change of basal crop coefficient and evaporation coefficient was similar for the film mulching and bare land treatments. The ratio of evaporation to crop evapotranspiration was calculated by using SIMDual_Kc model. The ratio of 2014 and 2015 were respectively 26.15%, 27.23% and 19.85%, 20.29% for bare land and film mulching. The ratio of film mulching was lower than that of bare land. The change amount of soil evaporation in bare land was 1.67-2.18 mm/d and that in film mulching was 1.33-2.17 mm/d. It showed that mulching can effectively reduce the soil evaporation, and has the potential to reduce crop water consumption. It can guide the production of corn under mulched drip irrigation in Northeast of Inner Mongolia.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Evapotranspiration
Controlled terms:Crops - Evaporation - Film growth - Films - Irrigation - Mean square error - Rain - Soil conservation - Soil moisture - Soil surveys - Transpiration - Water conservation - Water supply
Uncontrolled terms:Basal crop coefficients - Crop evapotranspiration - Evaporation coefficients - Inner Mongolia - Model calibration and validation - Mulched drip irrigations - Root mean square errors - Soil evaporation coefficients
Classification code:443.3 Precipitation - 444 Water Resources - 446.1 Water Supply Systems - 461.9 Biology - 483.1 Soils and Soil Mechanics - 802.3 Chemical Operations - 821.3 Agricultural Methods - 821.4 Agricultural Products - 922.2 Mathematical Statistics
Numerical data indexing:Percentage 1.00e+00%, Percentage 1.99e+01%, Percentage 2.03e+01%, Percentage 2.61e+01%, Percentage 2.72e+01%
DOI:10.11975/j.issn.1002-6819.2018.03.017
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 2>
Accession number:20181605031856
Title:Spatial heterogeneity of early-warning status of cultivated land system security and its driving factors in Heilongjiang Province
Authors:Song, Ge (1); Chen, Lili (1); Zou, Chaohui (1)
Author affiliation:(1) Institute of Land Management, Northeast University, Shenyang; 110819, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:1-9
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The study on spatial heterogeneity of the early-warning status of cultivated land system security (CLSS) and its driving factors at county level has an important role in accurately identifying the early-warning status of the CLSS and scientifically formulating the protection plan of cultivated land system. The purpose of this study was to explore and identify spatial heterogeneity characteristics of the early-warning status of the CLSS and its driving factors in Heilongjiang Province, which is located in main grain producing area of Northeast China. In the paper, exploratory spatial data analysis (ESDA) was used to identify spatial heterogeneity characteristics of the early-warning status of CLSS in 72 counties of Heilongjiang Province, and ordinary least squares (OLS) and geographical weighted regression (GWR) method were employed for exploring driving factors of the spatial heterogeneity of the early-warning status. The results indicated that: 1) The early-warning level of CLSS in general was relatively high in the counties of Heilongjiang Province. Of the 72 counties, 69 counties were in the early-warning status, and 28, 32 and 9 counties were low-level warning, medium-level warning and severe-level warning, respectively. 2) The spatial distribution of the early-warning status showed obvious heterogeneity and agglomeration characteristics of the early-warning status in the study area. The severe-level warning areas were mainly found in the southeast and west of the region, while the secure and relatively secure areas were mainly concentrated in the north-south axis belt areas. The counties with positive spatial autocorrelation (high-high type and low-low type) emerged with the "clusters" and had a powerful agglomeration. The counties with negative spatial autocorrelation (high-low type and low-high type) were few and showed sporadic distribution. 3) Twelve variables were preliminarily selected for exploring the driving factors of the early-warning status by OLS model, and 9 variables, including 3 natural-ecological factors (slope, elevation and annual average temperature) and 6 socioeconomic factors (per capita GDP (gross domestic product), urbanization level, investment in agricultural fixed assets, water-soil coordination degree, agricultural wastes index, and road network density) were determined for further analysis by the GWR model. The regression results by GWR model and ArcGIS spatial analysis showed the natural-ecological factors, including terrain and climate, and socioeconomic factors including the land input-output, land-water resources allocation, had a significant effect on the early-warning status of the CLSS. Moreover, the regression coefficients of these driving factors showed the significant spatial heterogeneity characteristics. In conclusion, the study on spatial heterogeneity of the early-warning status of the CLSS provides a reference for accurately identifying the spatial distribution of the early-warning status in Heilongjiang Province. Compared with OLS model, the GWR model visualizes the non-stationary characteristics of driving factors of the spatial heterogeneity of the early-warning status of the CLSS, which can be more intuitive and in-depth to explore the spatial difference of the effect of each driving factor on the early-warning status, and provide a scientific basis for formulating appropriate measures to mitigate future threats of the cultivated land system.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Spatial variables measurement
Controlled terms:Agglomeration - Agricultural wastes - Agriculture - Autocorrelation - Climate models - Economic and social effects - Economics - Factor analysis - Land use - Least squares approximations - Models - Motor transportation - Regression analysis - Spatial distribution - Water resources
Uncontrolled terms:Cultivated lands - Driving factors - Early warning - Heilongjiang - Spatial heterogeneity
Classification code:403 Urban and Regional Planning and Development - 444 Water Resources - 802.3 Chemical Operations - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.5 Agricultural Wastes - 921 Mathematics - 921.6 Numerical Methods - 922.2 Mathematical Statistics - 943.2 Mechanical Variables Measurements - 971 Social Sciences
DOI:10.11975/j.issn.1002-6819.2018.03.001
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 3>
Accession number:20181605031895
Title:Melatonin delaying senescence of postharvest broccoli by regulating respiratory metabolism and antioxidant activity
Authors:Zhu, Lingling (1, 2); Hu, Huali (1); Luo, Shufen (1); Wu, Zhaoxia (2); Li, Pengxia (1, 3, 4)
Author affiliation:(1) Institute of Agro-product Processing, Jiangsu Academy of Agricultural Sciences, Nanjing; 210014, China; (2) College of Food Science, Shenyang Agricultural University, Shenyang; 110866, China; (3) Engineering Laboratory for Horticultural Products Postharvest Treatment, Jiangsu Academy of Agricultural Sciences, Nanjing; 210014, China; (4) Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, Jiangsu Academy of Agricultural Sciences, Nanjing; 210014, China
Corresponding author:Li, Pengxia(pengxiali@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:300-308
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Broccoli (Brassica oleracea L. var. italica Planch) florets are one of the nutrient-rich vegetables, which contain carbohydrates, protein, carotenoids, dietary fiber, vitamins, antioxidant substances, and anti-carcinogenic compounds. Fresh broccoli is therefore highly popular. Color is an extremely important quality attribute of fresh broccoli. "Yellowing" is the term used to describe the color quality. Under ambient temperature, the florets yellow rapidly accompanied by chlorophyll degradation, and the shelf life of broccoli is only 2-3 d. Therefore, it is important to keep the green color as long as possible for quality maintenance. As a safe and beneficial indoleamine molecule, melatonin exists in different organs of plant, such as roots, stems, leaves, flowers and fruits. Apart from acting as endogenous elicitor and signaling role, melatonin has a direct antioxidant activity for attenuation of biotic and abiotic stress, including salt, drought, cold, and pathogens. The senescence of fruits and vegetables is usually accompanied by increased level of reactive oxygen species. However, whether melatonin regulates the senescence and yellowing of postharvest broccoli remains unknown. In this study, to explore an effective preservation technology for postharvest broccoli, the effects of 100 µmol/L melatonin treatment on the yellowing index, chromatic aberration, endogenous melatonin content, total chlorophyll content, respiratory pathway, energy level, and antioxidant activity of fresh-cut broccoli were investigated based on the results of our preliminary experiments. The results showed that, the yellowing index in no-treated and distill water-treated broccolis were 1.93, 2.08 on the sixth day, respectively. However, the yellowing index of melatonin-treated group was only 1.71 on the seventh day. Meanwhile, melatonin treatment inhibited the increase of the values of L<sup>*</sup>, a<sup>*</sup>, and b<sup>*</sup>. The contents of total chlorophyll in postharvest broccoli decreased with the extent of storage time, while the content of total chlorophyll in melatonin-treated group were 18.03%, 24.15% highter than that in no-treated and distill water-treated groups on the sixth day, respectively. Additionally, at the substrate oxidation level, melatonin treatment reduced the total respiration rate of postharvest broccoli florets by reducing the operating proportion of embden-meyerhof-parnas (EMP), tricarboxyfic acid cycle (TCA) and phosphopentose pathway (PPP). At the level of electron transport chain, melatonin treatment decreased the operating proportion of cytochrome pathway (CP) and increased the operating proportion of alternate pathway (AP) (P<0.05). Meanwhile, melatonin treatment maintained higher contents of adenosine triphosphate (ATP) and adenosine diphosphateadenosine (ADP), and a lower content of adenosine monophosphate (AMP), thereby showing a higher energy status in the melatonin-treated samples during the whole storage period (P<0.05). Furthermore, melatonin treatment ameliorated the accumulation of O<inf>2</inf><sup>•-</sup>and H<inf>2</inf>O<inf>2</inf>compared to the control broccolis (P<0.05), which might be associated with the increased activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), and the deduction was supported by an increased activities of SOD, CAT and POD isozymes. Overall, these results suggest that melatonin can delay the senescence process of postharvest broccoli florets through regulating the respiratory metabolism and antioxidant activity, which will provide a new theoretical basis for the application of melatonin and the preservation of broccoli.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:35
Main heading:Plants (botany)
Controlled terms:Aberrations - Adenosinetriphosphate - Antioxidants - Chlorophyll - Color - Crops - Electron transport properties - Energy storage - Enzymes - Fruits - Hormones - Metabolism - Physiology - Vegetables - Water treatment - Water treatment plants
Uncontrolled terms:Broccoli - Energy metabolism - Melatonin - Reactive oxygen species - Respiratory pathway
Classification code:445.1 Water Treatment Techniques - 461.2 Biological Materials and Tissue Engineering - 461.9 Biology - 525.7 Energy Storage - 741.1 Light/Optics - 804.1 Organic Compounds - 821.4 Agricultural Products
Numerical data indexing:Percentage 1.80e+01%, Percentage 2.41e+01%
DOI:10.11975/j.issn.1002-6819.2018.03.040
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 4>
Accession number:20181605031894
Title:Effect of environmental factors on growth/non-growth interface of Vibrio alginolyticus isolated from lightly salted Pseudosciaena crocea
Authors:Guo, Quanyou (1); Zhu, Yanqi (1, 2); Jiang, Chaojun (1); Li, Baoguo (2)
Author affiliation:(1) East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai; 200090, China; (2) School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai; 200093, China
Corresponding author:Li, Baoguo(lbaoguo@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:292-299
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The aim of the study was to develop a growth/no-growth interface model to predict the growth probability of Vibrio alginolyticus associated with lightly salted Pseudosciaena crocea under 3 environmental factors, and to explore the inhibitory effect of environmental factors on the growth kinetics of target micro-organism. The effects of pH value, water activity (aw) and NaCl content on the growth probability of the Vibrio alginolytica were studied at ambient temperature (25℃). At present, mainly the "fence technology" is used to change the growth environment of microorganisms by changing the water activity, salt, acetic acid, Nisin and sugar, so as to achieve the role of inhibition to microorganisms. Logistic regression is a commonly used method for simulating the microbial growth boundary (growth/non-growth interface) in food, through which the growth environment can be adjusted and the shelf life can be extended. Artificial neural network model PNN (probabilistic neural network) is a feed forward neural network with strong nonlinear pattern classification ability and high accuracy of nonlinear algorithm, which can solve the growth/non-growth interface problems, and the PNN has simple structure and high training speed without considering the complex chemical reaction during storage. Simple logistic equation, second-order linear logistic regression equation and PNN artificial neural network model were used to establish the growth/non-growth interface model of Vibrio alginolyticus, while fraction correct (FC) and false alarm rate (FAR) were used to compare the goodness of fit of the 3 models. The Gompertz model was used to fit the growth condition, and the growth kinetics parameters were obtained. The results showed that the second-order linear logistic regression equation had better fitting results, the consistency index of the training set was 94.8%, and that of the validation set was 90.9%, while the consistency index of the PNN artificial neural network was 95.6% and 90.0% for the training and validation set, respectively. The FAR of the second-order linear logistic regression equation was 5% (training set) and 0 (validation set), while that of the PNN artificial neural network was 6.6% (training set) and 22% (validation set). The effects of the environmental factors were as follows: With the increase of salt content, the growth/no-growth boundary obviously moved to low water activity and low pH value. In the same salty condition, in the range of high aw and high pH value, the growth rate was higher and the retardation period was shorter. With the increase of salt content, even under low aw such as 0.91 and 0.90, the Vibrio alginolyticus also began to grow slowly, but there was a long lag time. The conclusions are obtained: PNN artificial neural network can do quick classification prediction on the growth/no-growth data of Vibrio alginolyticus in the industrial production, and the second-order linear logistic regression can evaluate the stability of aquatic products under the conditions of aw, pH value and salt content. By constructing the probabilistic models and kinetic models of Vibrio alginolyticus which can assess the stability of characteristic aquatic products in the range of pH value, aw and salt content, it can provide the guide to suppress microorganisms without the use of chemical preservatives to ensure quality and safety of pickled Pseudosciaena crocea.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Growth kinetics
Controlled terms:Bacteria - Chemical stability - Digital storage - Environmental impact - Fish - Kinetics - Microorganisms - Models - Neural networks - pH effects - Regression analysis - Sodium chloride
Uncontrolled terms:Artificial neural network modeling - Chemical preservatives - Classification prediction - Complex chemical reactions - Logistic regression equations - Probabilistic neural networks - Pseudosciaena crocea - Vibrio alginolyticus
Classification code:454.2 Environmental Impact and Protection - 461.9 Biology - 722.1 Data Storage, Equipment and Techniques - 801 Chemistry - 801.1 Chemistry, General - 922.2 Mathematical Statistics - 931 Classical Physics; Quantum Theory; Relativity
Numerical data indexing:Percentage 2.20e+01%, Percentage 5.00e+00%, Percentage 6.60e+00%, Percentage 9.00e+01%, Percentage 9.09e+01%, Percentage 9.48e+01%, Percentage 9.56e+01%
DOI:10.11975/j.issn.1002-6819.2018.03.039
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 5>
Accession number:20181605031882
Title:Analysis of heat transfer characteristics for parabolic trough solar collector system with heat-pipe evacuated tube
Authors:Zhang, Weiwei (1, 2); Wang, Jiabin (1); Tian, Rui (1, 3); Xue, Qicheng (4); Ba, Xuyang (1)
Author affiliation:(1) The College of Energy and Power Engineering, Inner Mongolia University of Technology, Hohhot; 010051, China; (2) Key Laboratory of Wind Energy and Solar Energy Technology, Inner Mongolia University of Technology, Ministry of Education, Hohhot; 010051, China; (3) Key Laboratory of Renewable Energy, Inner Mongolia Autonomous Region, Hohhot; 010051, China; (4) School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University, Beijing; 100044, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:202-209
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Heat pipe is an efficient heat transfer component. If the heat pipe and the trough concentrator with higher concentration ratio can be effectively combined, the operating temperature of working fluid can be increased obviously, thus achieving higher system thermal efficiency. Parabolic trough solar collector system with heat-pipe evacuated tube is designed in this paper to provide enough heat input to raise the temperature of an heat transfer fluid to around 200℃. The system consists of parabolic trough solar concentrator, heat-pipe evacuated tube (a heat collector element) and support structure. The heat-pipe evacuated tube with material of stainless steel consists of evaporator and condenser sections, and water is used as the working liquid. The evaporator section inside a glass envelope is about 45 mm in diameter with a special coating (selective coating) on the outside surface to provide the required optical properties. The selective coating has a high absorptance for radiation in the solar energy spectrum, and has low emittance in the long wave energy spectrum to reduce thermal radiation losses. The annulus space between the evaporator section and the glass envelope is under vacuum to reduce thermal losses. The condenser section of the heat pipe is inserted into the jacketed vessel and rejects heat to the heat transfer fluid. In order to analyze thermal efficiency and provide theoretical basis for collector system design, a one-dimensional heat transfer mathematical model was established. Using this model, heat transfer characteristics of the system were calculated and analyzed. The results indicate that the transient thermal efficiency of the parabolic trough solar collector system with heat-pipe evacuated tube is higher than 70%, and increases with the increase of the ambient temperature and direct normal solar insolation, and decreases with the increase of the heat transfer fluid temperature and wind speed. Working liquid in heat pipe is at saturated state when the system is running, and the temperature is affected mainly by temperature of absorber tube inner wall. The working liquid temperature in heat pipe increases with the increase of direct normal solar insolation, heat transfer fluid temperature and ambient temperature, and decreases with the increase of wind speed. The working liquid temperature in heat pipe is about 327.6-503.2 K under the given calculation condition. Operating pressure of heat-pipe evacuated tube is obtained by the operating temperature of working liquid, and is about 0.016-2.8 MPa in this paper. The working liquid temperature in this paper is within the optimal range with water as the working liquid in the heat pipe. The heat transfer characteristics of the system are influenced obviously by annulus pressure. Annulus pressures below 0.001 Pa have slight influence on the system performance. But under the annulus pressure above 0.001Pa, the heat loss of the collector increases significantly with the increase of annulus pressure. The system performance is also influenced by the type of gases in the annulus space. Heat loss of the collector is changed with the gases (air, hydrogen and argon) in the annulus space and heat transfer fluid temperature. An inert gas with a high thermal condition coefficient, such as hydrogen, results in the higher heat loss of the collector. The encouraging results in this paper will provide a fundamental reference for researching heat-transfer characteristics and optimization design and performance of parabolic trough solar collector system with heat-pipe evacuated tube.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Heat transfer
Controlled terms:Air - Coatings - Collector efficiency - Concentration (process) - Condenser tubes - Evaporators - Glass - Heat losses - Heat pipes - Hydrogen - Incident solar radiation - Inert gases - Liquids - Mathematical models - Optical properties - Solar concentrators - Solar energy - Spectroscopy - Temperature - Tubes (components) - Wave energy conversion - Wind
Uncontrolled terms:Evacuated tubes - Evaporator and condensers - Heat transfer characteristics - One-dimensional heat - Operating temperature - Parabolic trough - Parabolic trough solar collectors - Transient thermal efficiency
Classification code:443.1 Atmospheric Properties - 615.6 Wave Energy - 619.1 Pipe, Piping and Pipelines - 641.1 Thermodynamics - 641.2 Heat Transfer - 657.1 Solar Energy and Phenomena - 702.3 Solar Cells - 741.1 Light/Optics - 802.1 Chemical Plants and Equipment - 804 Chemical Products Generally - 804.2 Inorganic Compounds - 812.3 Glass - 813.2 Coating Materials
Numerical data indexing:Percentage 7.00e+01%, Pressure 1.00e-03Pa, Pressure 1.60e+04Pa to 2.80e+06Pa, Size 4.50e-02m, Temperature 3.28e+02K to 5.03e+02K
DOI:10.11975/j.issn.1002-6819.2018.03.027
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 6>
Accession number:20181605031883
Title:Relationship between chaotic characteristics of nanofluid boiling and heat transfer enhancement in microchannels of heat exchanger
Authors:Luo, Xiaoping (1); Guo, Feng (1); Wang, Wen (1); Liao, Zhengbiao (1)
Author affiliation:(1) School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou; 510640, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:210-218
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Micro channel heat exchanger has become the focus of scholars as a kind of highly efficient heat transfer equipment, and the nanofluid flow boiling heat transfer in microchannels is a hot topic at present. The flow boiling as a vapor-liquid two-phase flow, including a series of sub-processes of generation, growth, detachment and interaction of many boiling bubbles, is complex nonlinear system, and their nonlinear characteristics have an important influence on the boiling heat transfer performance of the entire microchannels. The simple experimental analysis method adopted by scholars does not accurately describe the dynamic characteristics of the flow boiling system in microchannel. Therefore, in order to investigate the heat transfer characteristics, non-linear characteristics and their interrelationships of nanofluid flow boiling system in microchannels, uniform and stable 0.05-0.30 wt% Al<inf>2</inf>O<inf>3</inf>/R141b nanofluids were prepared as the experimental working fluid and the experimental platform was built, and the flow boiling test was carried out in the microchannels of 2 mm × 2 mm under the heat flux of 14-46 kW/m<sup>2</sup>, mass flow rate of 310.5 kg/(m<sup>2</sup>∙s), and system pressure of 165 kPa. The boiling heat transfer coefficient is calculated through the heat transfer model and the univariate time series is established by importing and exporting pressure data through the experimental section. The nonlinear characteristics of the time series are studied by Hurst exponential analysis, correlation dimension, maximum Lyapunov number and Kolmogorov entropy. The relationship between the nonlinear characteristics and the heat transfer performance is also compared. The results show that the boiling heat transfer coefficient of nanofluids first increases and then decreases with the increase of heat flux density under the experimental conditions, and the heat transfer coefficient reaches the maximum at 38 kW/m<sup>2</sup>heat flux density. The flow boiling of the nanofluid Al<inf>2</inf>O<inf>3</inf>/R141b and pure refrigerant R141b in the microchannels shows chaotic characteristics. The Hurst exponent is greater than 0.5, and the correlation dimension, the maximum Lyapunov exponent and the K entropy are all finite values greater than 0. Compared to pure refrigerant, the chaotic degree of the flow boiling system is stronger and the heat transfer performance is also better. The concentration has a significant effect on the nonlinear characteristics and heat transfer coefficient of the nanofluid boiling system, the chaos degree of the nanofluid increases first and then decreases with the increase of the concentration of nanoparticles, and its boiling heat transfer coefficient also increases first and then decreases. Under the experimental conditions, the non-linear characteristics of 0.10% nanofluid reach the maximum and the corresponding boiling heat transfer coefficient is also the largest, and the average boiling heat transfer coefficient is about 76% higher than that of pure refrigerants. The analysis believes this result is the comprehensive effect of nanoparticles on the vapor-liquid interface and its deposition on the channels surface. The effect of nanoparticles on the vapor-liquid interface can make the gas-liquid-solid three-phase line move toward the gas phase, the diameter of bubbles smaller and the frequency of disengagement increase. As a result, the turbulence intensity of the fluid in the microchannels is increased and the chaos of the system is stronger and the heat transfer performance is better. The deposition of nanoparticles on the channels yet can increase the wall thermal resistance and wall wettability, resulting in a smaller number of bubbles, thereby reducing the chaos degree of system and heat transfer efficiency. They are 2 diametrically opposed mechanisms that have led to the above experimental results. In this paper, the method of combining nonlinear analysis and experiment is introduced into the study of flow boiling in microchannels. Compared with the traditional analytical methods, the kinetic characteristics of the flow boiling system in microchannels can be more accurately described and the mechanism of nano-fluid enhanced phase heat transfer is further revealed.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:34
Main heading:Nanofluidics
Controlled terms:Alumina - Aluminum oxide - Chaos theory - Deposition - Entropy - Heat exchangers - Heat flux - Heat resistance - Heat transfer - Heat transfer coefficients - Heating equipment - Liquids - Lyapunov methods - Microchannels - Nanoparticles - Nonlinear analysis - Phase interfaces - Phase transitions - Refrigerants - Time series - Time series analysis - Two phase flow - Walls (structural partitions)
Uncontrolled terms:Boiling heat transfer performance - Boiling heat-transfer coefficients - Experimental analysis method - Flow boiling - Gas liquid solid three phase - Heat transfer characteristics - Micro-channel heat exchangers - Nanofluids
Classification code:408.2 Structural Members and Shapes - 616.1 Heat Exchange Equipment and Components - 631.1 Fluid Flow, General - 641.1 Thermodynamics - 641.2 Heat Transfer - 761 Nanotechnology - 801.4 Physical Chemistry - 802.3 Chemical Operations - 803 Chemical Agents and Basic Industrial Chemicals - 804.2 Inorganic Compounds - 922.2 Mathematical Statistics - 933 Solid State Physics - 961 Systems Science
Numerical data indexing:Percentage 1.00e-01%, Percentage 7.60e+01%, Pressure 1.65e+05Pa, Size 2.00e-03m, Surface_Power_Density 1.40e+04W/m2 to 4.60e+04W/m2, Surface_Power_Density 3.80e+04W/m2
DOI:10.11975/j.issn.1002-6819.2018.03.028
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 7>
Accession number:20181605031868
Title:Clogging characteristic of different emitters in drip irrigation with hard water
Authors:Liu, Yanfang (1); Li, Dan (1); Wu, Pute (1, 2); Zhang, Lin (2, 3); Zhu, Delan (1); Chen, Junying (1)
Author affiliation:(1) College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling; 712100, China; (2) China Arid-area Water-saving Agricultural Institute, Northwest A&F University, Yangling; 712100, China; (3) Institute of Soil and Water Conservation, Northwest A&F University, Yangling; 712100, China
Corresponding author:Wu, Pute(gjzwpt@vip.sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:96-102
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Emitter clogging is an unavoidable problem when the hard water is used for drip irrigation and it is tightly related to the form and size of the internal structure. This study was designed to evaluate the performance of 6 types of emitters for drip irrigation by using ultrapure water and hard water, and main characteristic parameters influencing clogging were determined. A total of 6 emitters were used for the test. Among them, 3 were non-pressure-compensated, 2 were molded and welded into dripline wall, and 1 was inserted into thick wall. The other 3 emitters, being inserted into thick wall, were all pressure-compensated. The hard water was prepared at 500 mg/L using ultrapure water and chemical reagents (CaCl<inf>2</inf>and NaHCO<inf>3</inf>). The experiment was carried out at the Irrigation Hydraulics Laboratory of Northwest A&F University, from October 2014 to January 2015 and from May 2015 to July 2015. A drip irrigation system with cyclic water was built, which had 12 laterals. Each of these emitters was installed to the 2 of laterals. The drip irrigation system was operated at a regime of 4 h operation a week under a regulated pressure of 100 kPa. The water delivered for each emitter was collected for 10 min to measure the flow rate of the emitters every other week. The emitter's average relative flow rate and the emitter clogging ratio were calculated for 26 weeks to evaluate the emitter performance. The ordinal regression analysis was used to analyze the influence of characteristic parameters on emitter clogging. The emitter characteristics used included pressure-compensation, nominal flow rate, water passage length, water inlet fence and the minimum size in the width and depth of flow passage section. All of the emitters were dissected after all the irrigation events. Photos of the emitter interior structures were taken by a camera (Canon PowerShot SX500 IS). Then the clogging was assessed by information of sediment deposition inside the emitter. The results showed that the decline in average relative flow rate was observed with 6 kinds of emitters during the drip irrigation system running time. Emitter E1 and E6 had the best performance. On the contrary, emitter E4 showed the worst performance. And emitter E3 was observed a highest emitter clogging ratio after 2 weeks. Ordinal regression analysis showed that the effect of the minimum size of flow passage section on the emitter anti-clogging ability was statistically significant (P<0.01). And the anti-clogging ability of emitter had a positive correlation with the minimal size of flow passage section. As the minimal size of flow passage section increased, the emitter anti-clogging ability was improved. The other emitter characteristics were not found to be statistically significant (P>0.05). Dissection of emitters revealed that clogged occurred at different areas for different emitters. E1 was mainly clogged at the head of the labyrinth flow passage. E2 was clogged at the fence where the water entered from. E3 was mainly clogged at the head of the labyrinth flow passage behind the fence. E4, E5 and E6 were mainly clogged at a little narrow groove, which was used to achieve a function of pressure compensation. The emitter clogging of 6 types mainly occurred at the flow passage section with the minimal size. When there was more than 1 area with the minimal size of flow passage section inside the emitter, clogging had tended to occur at an area that particles was easily to deposit on. This area was called by "low velocity area". Thus, choosing emitters with the larger water passage section and avoiding the flow passage easily causing deposition are important when hard water is used for drip irrigation. These results can provide important information for understanding emitter clogging mechanism and some suggestions for scientific emitter selection of hard water irrigation system.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Flow rate
Controlled terms:Chlorine compounds - Deposition - Dissection - Fences - Irrigation - Regression analysis - Sodium bicarbonate - Walls (structural partitions) - Water hardness
Uncontrolled terms:Clogging - Drip irrigation - Emitters - Hard water - Regression
Classification code:408.2 Structural Members and Shapes - 445.2 Water Analysis - 461.6 Medicine and Pharmacology - 631 Fluid Flow - 802.3 Chemical Operations - 804 Chemical Products Generally - 821.3 Agricultural Methods - 922.2 Mathematical Statistics
Numerical data indexing:Age 3.84e-02yr, Mass_Density 5.00e-01kg/m3, Pressure 1.00e+05Pa, Time 1.44e+04s
DOI:10.11975/j.issn.1002-6819.2018.03.013
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 8>
Accession number:20181605031879
Title:Spectral feature selection and discriminant model building for citrus leaf Huanglongbing
Authors:Liu, Yande (1); Xiao, Huaichun (1); Sun, Xudong (1); Zhu, Danning (1); Han, Rubing (1); Ye, Lingyu (1); Wang, Jungang (1); Ma, Kuirong (1)
Author affiliation:(1) College of Mechanical and Electrical Engineering, East China Jiaotong University, Nanchang; 330013, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:180-187
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Citrus greening is a devastating disease of citrus fruit trees, and at present, it is potential for greening diagnosis by hyperspectral imaging technique. The purpose of this paper is to explore the feasibility of diagnosis and classification of greening using hyperspectral technique, and provide the reference for practical application of high-dimensional data. The hyperspectral images of citrus leaves were collected and divided into 5 types: slight greening, moderate greening, serious greening, nutrient deficiency and normal by common PCR (polymerase chain reaction). The samples of normal, nutrient deficiency, slight, moderate and serious greening show bright band in turn and the bright band colors are getting brighter with the grade of the disease. The bright band of nutrient deficiency samples by PCR is more vague than the greening samples, which may be related to the lack of nutrient elements. A total of 169 samples are divided into the calibration and prediction set for calibrating the models and accessing their performance respectively according to the proportion of 3: 1. The calibration set includes 25 slight citrus greening samples, 21 moderate citrus greening samples, 26 serious citrus greening samples, 26 nutrient deficiency samples and 29 normal samples. The prediction set includes 6 slight citrus greening samples, 13 moderate citrus greening samples, 6 serious citrus greening samples, 10 nutrient deficiency samples and 7 normal samples. From the representative pictures of the 5 kinds of leaves, it can be seen intuitively that the leaves of greening present similar symptoms with the nutrient deficiency leaves, which are obviously different from the normal leaves. But it is difficult to distinguish between the leaves with slight, moderate, serious greening and nutrient deficiency. The average spectrum of hyperspectral images of leaves is extracted in the region of interest. The results show that strong reflection peak of chlorophyll is located at 550 nm, and greening hinders plant photosynthesis, resulting in the reflection peak of the leaves is significantly higher than the normal leaves; another more obvious reflection peak is at the 720 nm original hyperspectral spectrum, which is mainly caused by 4 frequency doubling stretching vibration of O-H. Due to the low water content of the leaves of greening, the reflection peak is lower than the normal leaves, and decreases gradually with the grade of the disease, and the reflection peak of leaves with serious greening is the lowest. The reflection peaks of leaves with nutrient deficiency may be caused by the lack of nutrient elements such as iron, nitrogen and zinc. The irrelevant information is eliminated by uninformative variable elimination (UVE), and genetic algorithm (GA) and continuous projection algorithm (SPA) are combined to screen the variables for data dimensionality reduction. Combining extreme learning machine (ELM) and least squares-support vector machine (LS-SVM), the discrimination model for citrus greening is developed. Diagnosis and classification are carried out for the predicted samples to evaluate the discrimination ability of the model. The results show that the effect of LS-SVM model with input variables screened by UVE combined with SPA is the best. At this time, the Link_kernel function is the kernel function of this model, the least punishment factor is 1.07, The lowest misjudgment rate is 0. The LS-SVM model has the highest degree of complexity and the worst prediction ability with the full spectrum as input variables, the highest misjudgment rate is 11.9%, which may be caused by the useless information and redundant information variables.. The results show that it is feasible to diagnose and classify citrus greening with LS-SVM using hyperspectral technique, whose input variables were screened using the combination of UVE and SPA, and the reference value is provided for the practical application of high-dimensional data.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Plants (botany)
Controlled terms:Calibration - Citrus fruits - Clustering algorithms - Computer aided diagnosis - Crops - Diseases - Forecasting - Frequency doublers - Genetic algorithms - Hyperspectral imaging - Image segmentation - Models - Nutrients - Orchards - Polymerase chain reaction - Spectroscopy - Stretching - Support vector machines
Uncontrolled terms:Data dimensionality reduction - Discrimination ability - Extreme learning machine - Hyperspectral imaging technologies - Hyperspectral techniques - Least squares support vector machines - Successive projections algorithm - Uninformative variable eliminations
Classification code:535.2 Metal Forming - 713.5 Electronic Circuits Other Than Amplifiers, Oscillators, Modulators, Limiters, Discriminators or Mixers - 723 Computer Software, Data Handling and Applications - 723.5 Computer Applications - 801.2 Biochemistry - 821.3 Agricultural Methods - 821.4 Agricultural Products - 903.1 Information Sources and Analysis
Numerical data indexing:Percentage 1.19e+01%, Size 5.50e-07m, Size 7.20e-07m
DOI:10.11975/j.issn.1002-6819.2018.03.024
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 9>
Accession number:20181605031885
Title:Optimization of process parameters on carbon-based solid acid catalyzing bio-oil esterification for reducing acidity
Authors:Tan, Wenying (1); Cheng, Xiaohong (1); Wang, Shuyang (2); Li, Jianshun (1)
Author affiliation:(1) Material Science and Engineering College, Northeast Forestry University, Harbin; 150040, China; (2) College of Mechanical and Electrical Engineering, Northeast Forestry University, Harbin; 150040, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:227-233
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:As an ideal clean energy, biomass is friendly to the environment. Bio-oil is a brown and black viscous liquid obtained by rapid pyrolysis of biomass under anoxic conditions. As a kind of liquid fuel, it has the disadvantages of high acid value, high water content, high viscosity and low calorific value. In addition, bio-oil is the mixture of hundreds of chemicals. Carboxylic acids enhance corrosion resistance of bio-oil. Amounts of water reduce the calorific value of the bio-oil. Aldehydes and other labile compounds make the bio-oil coking or polymerize easily during storage, with the increased viscosity, affecting the quality of the bio-oil. In this experiment, in order to reduce the content of carboxylic acid in bio-oil, the carbon-based solid acid catalysts were used to catalyze esterification of bio-oil. In the experiment, 4 kinds of carbon-based solid acid catalysts were prepared by incomplete carbonization and carbonization-sulfonation. They were starch-TsOH, sucrose-TsOH, glucose-TsOH and corn flour-sulfuric acid. The catalysts were characterized by FTIR (Fourier transform infrared spectroscopy), indicating that the carbon-based solid acid catalyst is an aromatic carbon compound with sulfonic groups. Esterification was carried out with acid and alcohol as model compounds. Among the 4 catalysts, starch-TsOH had the highest esterification rate, and the conversion of acetic acid reached 91.58%. The effects of reaction temperature, reaction time, catalyst mass fraction and ratio of alcohol to acid on the conversion of acetic acid were investigated by single factor experiment. Response surface methodology was used to optimize the catalytic esterification conditions of the bio-oil model compound. The optimum reaction conditions were as follows: reaction temperature 100℃, alkyd ratio 3.37, reaction time 2.49 h, and catalyst mass fraction 5.26%, and the acetic acid conversion rate reached 95.51%. Under these conditions, 3 validation experiments were carried out, the conversion rates were 94.89%, 94.26% and 95.01%, respectively, and the relative deviation was 0.83%, which was very close to the predicted value. This indicated that the model was reliable for the analysis and prediction of the optimum esterification conditions. Under the optimum reaction conditions, the starch-TsOH catalyst was reused 5 times, and the activity of the catalyst was investigated. The results showed that the catalyst was deactivated seriously after 4 times, and the conversion rate of acetic acid was reduced to 52.14%. After esterification of bio-oil with methanol, ethanol and n-butanol, the carboxylic acid was converted into neutral ester, and the acid value was reduced by 82.82%-91.41%. Moreover, after esterification, the density and viscosity of bio-oil decreased obviously, and the calorific value increased. The bio-oil and esterified bio-oil were analyzed by FTIR and GC-MS (gas chromatography-mass spectrometer), which showed that some carboxylic acids in bio-oil were converted into esters, some acetals were produced, and phenols were unchanged basically. So, in the future experiments, we should consider how to make better use of phenolic compounds. After esterification and dehydration of bio-oil, the water content of bio-oil was reduced to 2.5%, and the calorific value was increased. The effect was significant, which indicated the necessity of water separation.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Biofuels
Controlled terms:Acetic acid - Biomass - Calorific value - Catalyst activity - Coking - Corrosion resistance - Esterification - Esters - Fourier transform infrared spectroscopy - Fueling - Gas chromatography - pH - Phenols - Spectrometers - Starch - Viscosity
Uncontrolled terms:Bio oil - Carbon-based solid acid catalysts - Catalytic esterification - Catalytics - Gas chromatography-mass spectrometers - Optimization of process parameters - Optimum reaction conditions - Response surface methodology
Classification code:524 Solid Fuels - 539.1 Metals Corrosion - 631.1 Fluid Flow, General - 741.3 Optical Devices and Systems - 801 Chemistry - 801.1 Chemistry, General - 802.2 Chemical Reactions - 802.3 Chemical Operations - 803 Chemical Agents and Basic Industrial Chemicals - 804 Chemical Products Generally - 804.1 Organic Compounds
Numerical data indexing:Percentage 9.16e+01%, Percentage 9.43e+01%, Percentage 9.49e+01%, Percentage 9.50e+01%, Percentage 9.55e+01%, Time 8.96e+03s, Percentage 2.50e+00%, Percentage 5.21e+01%, Percentage 5.26e+00%, Percentage 8.28e+01% to 9.14e+01%, Percentage 8.30e-01%
DOI:10.11975/j.issn.1002-6819.2018.03.030
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 10>
Accession number:20181605031865
Title:Test and modeling on static ground pressure of rubber track conversion system
Authors:Zhao, Zihan (1, 2); Mu, Xihui (2); Guo, Haoliang (3); Lv, Kai (4); Du, Fengpo (2)
Author affiliation:(1) Department of Ammunition Engineering, Army Engineering University, Shijiazhuang; 050003, China; (2) Special Services Institute, Shijiazhuang; 050003, China; (3) Artillery and Air Defense Corps Research Institute of Equipment and Technologies, Beijing; 100012, China; (4) Military Transportation University, Tianjin; 300161, China
Corresponding author:Mu, Xihui(mxh@vip.163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:72-79
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Rubber track conversion system is typically fitted instead of tyres on vehicles, with the aim of decreasing ground pressure, improving the trafficability, and protecting the soil. It is important to accurately predict its ground pressure. The configuration of rubber track conversion system is generally triangle, and the integral structure, road wheels' arrangement and track size are different from integrated track system. In this paper, the ground pressure distribution under rubber track conversion system was analyzed, and a prediction model for ground pressure distribution was established based on the test data. Firstly, the ground pressure under rubber track conversion system on solid and soft ground was tested by using Tekscan pressure measurement system. The test results showed its ground pressure distribution had the characteristics of both tracked vehicles and wheeled vehicles, but was different from the two. When rubber track conversion system was on the solid ground, the distribution of ground pressure was similar to tracked vehicles in the longitudinal direction, showing a multi-peak discontinuous trend. The ground pressure of track between load wheels was almost 0, and the peak distribution was similar to wheeled vehicles, showing a bell-type trend. The greater the load, the more uniform the peak. In the lateral direction, the distribution was uniform and continuous under the track, also showing a bell-type trend. When rubber track conversion system was on the soft ground, the distribution of ground pressure was multi-peak and continuous in the longitudinal direction. The peak distribution also showed a bell-type trend. In the lateral direction, the distribution of ground pressure on the soft ground was similar to its distribution on the solid ground. Secondly, according to the test data, a mathematical model of the ground pressure under the rubber track conversion system was proposed. In the longitudinal direction, the ground pressure was expressed by the second cosine function, and in the lateral direction, the ground pressure was expressed by a linear function. Model input parameters included the load on the track, track width, track length, number of road wheels, road wheel diameter, and so on. The ground hardness parameter of model was used to represent various ground conditions. The more soft the ground, the greater the value of this parameter. Then, simulation results derived from the mathematical model and experimental data were compared and analyzed. When rubber track conversion system was on the solid ground, the model could predict the peak under road wheels and the distribution of the ground pressure at the middle and the edge of road wheels, while the model could not perfectly predict the ground pressure of track between road wheels. When rubber track conversion system was on the soft ground, the model could predict the distribution of ground pressure and the peak under road wheels; the smaller the load on the track, the greater the model error. Compared with other models, the hardness parameter which represents the various ground condition can avoid the plate sinkage and shearing test, improving the practicability of the model. Finally, based on the predict model, the calculation equations of static steering resistence moment for rubber track conversion system were deduced for solid and soft ground. By comparing the calculated value with the test data, the results showed that the maximum error of the simulation results and test data was about 4.71%, so the model can be applied to the analysis of the steering performance of the rubber track conversion system. The proposed predict model can provide realistic estimates of the ground pressure and can also be used for structural design and other performance studies of rubber track conversion system.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Rubber
Controlled terms:Automobile steering equipment - Bells - Cosine transforms - Forecasting - Hardness - Models - Pressure distribution - Roads and streets - Steering - Structural design - Tracked vehicles - Vehicle wheels - Vehicles - Wheels
Uncontrolled terms:Conversion systems - Ground pressure - Integral structures - Lateral directions - Longitudinal direction - Peak distribution - Pressure measurement system - Steering performance
Classification code:406.2 Roads and Streets - 408.1 Structural Design, General - 601.2 Machine Components - 662.4 Automobile and Smaller Vehicle Components - 663 Buses, Tractors and Trucks - 752.1 Acoustic Devices - 818.1 Natural Rubber - 921.3 Mathematical Transformations - 931.1 Mechanics - 951 Materials Science
Numerical data indexing:Percentage 4.71e+00%
DOI:10.11975/j.issn.1002-6819.2018.03.010
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 11>
Accession number:20181605031893
Title:Molecular interaction analysis between collagen and chitosan blend film based on infrared spectroscopy
Authors:Gao, Lingling (1); Wang, Zhenyu (1); Rao, Weili (1); Cao, Lichuang (1); Zhang, Dequan (1)
Author affiliation:(1) Key Laboratory of Agro-Products Processing, Institute of Agro-Products Processing Science and Technology, Chinese Academy of Agricultural Sciences, Beijing; 100193, China
Corresponding author:Zhang, Dequan(dequan_zhang0118@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:285-291
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Collagen, as the most abundant structural protein in living bodies, constitutes approximately 30% of the total proteins. Collagen exhibits excellent film-forming property, and can be used be as an outstanding carrier of bioactive compounds (antioxidant and antimicrobial) for food packaging. However, the rough surface and defects in mechanical properties limit application of collagen film for food packaging. Chitosan, industrially produced by partial deacetylation of chitin, is also one kind of excellent natural film-forming material. The incorporation of chitosan can increase the antimicrobial ability of packaging film. Chitosan-gelatin blend films show better material properties when compared to pure single-component polymer films. The previous studies inferred hydrogen bonds and electrostatic interactions were formed between collagen and chitosan molecules during the process of film formation using one-dimensional infrared spectroscopy. Two-dimensional infrared correlation spectroscopy is a method to study the intermolecular interactions between functional groups under the interference of exogenous factors. The two-dimensional infrared correlation spectroscopy can also obtain the sensitivity and response order of the functional groups to external disturbance. At present, the interaction between bone collagen and chitosan has not been reported by two-dimensional infrared correlation spectroscopy. The paper aimed to infer the interaction by analyzing the characteristics of two-dimensional infrared correlation spectroscopy of bone collagen-chitosan blend film with different mixing ratios. Collagen, extracted from sheep bone by pepsin, and chitosan were mixed evenly according to 100: 0, 60: 40, 50: 50, 40: 60 and 0: 100, respectively, and then 25% glycerol was added as plasticizer. The mixed film-forming solution was dried at 50℃ for 18 h, and then placed at room temperature for 6 h and uncovered. Fourier transform infrared spectroscopy (FTIR) of blending film was obtained and analyzed by the peak fitting and two-dimensional correlation analysis to infer the interaction between collagen and chitosan molecules. Infrared spectroscopy showed that the intensity and shape of infrared absorption peaks changed obviously with the addition of chitosan. The results showed that conformation of C=O bond of bone collagen varied first with the addition of chitosan. The peak fitting results showed that the secondary structure of collagen in the blend film was mainly β sheet. The content of α helix decreased, and the content of β sheet and β turn increased after adding chitosan. The change of secondary structure of collagen in the blend film may be caused by the film forming process, such as the blending temperature and drying temperature. The secondary structure of collagen extended gradually, and further characteristic group was exposed. FTIR results proved the higher deacetylation degree of chitosan. The existence of two-dimensional infrared correlation peak involved in C-O-C bond of glycosyl skeleton confirmed the spatial conformation of chitosan varied. The infrared spectrum of N-H bond vibration varied significantly after adding chitosan. The hydroxyl, amine, and carboxyl groups of collagen were capable of forming hydrogen bonds with hydroxyl and amine groups of chitosan. The electrostatic interaction was formed between collagen and chitosan whose-NH<inf>2</inf>groups were easily protonated in acidic solutions and converted to-NH<inf>3</inf><sup>+</sup>. Two-dimensional infrared correlation spectroscopy indicated the response order of groups to mixture ratio was: 1633 cm<sup>-1</sup>> 1448 cm<sup>-1</sup>> 1236 cm<sup>-1</sup>> 1068 cm<sup>-1</sup>> 997 cm<sup>-1</sup>> 896 cm<sup>-1</sup>. The intensity and maximum wavenumbers of absorption peaks confirmed that the intermolecular hydrogen bonds appeared between collagen and chitosan in blend films, which were dependent on the ratio of collagen/gelatin to chitosan. In conclusion, the present study shows that hydrogen bonding and electrostatic interaction are formed between collagen and chitosan molecules in blending film, and the strength of intermolecular interaction is related to mixture ratio of collagen and chitosan.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:34
Main heading:Fourier transform infrared spectroscopy
Controlled terms:Acetylation - Blending - Bone - Chitosan - Collagen - Conformations - Electrostatic separators - Electrostatics - Hydrogen bonds - Infrared spectroscopy - Light absorption - Microorganisms - Mixtures - Molecules - Packaging machines - Polymer films - Spectrum analysis - Surface defects
Uncontrolled terms:Antimicrobial ability - Blend films - Correlation spectroscopy - Film-forming materials - Film-forming properties - Intermolecular hydrogen bonds - Intermolecular interactions - Twodimensional correlation analysis
Classification code:461.2 Biological Materials and Tissue Engineering - 461.9 Biology - 694.3 Packaging Equipment - 701.1 Electricity: Basic Concepts and Phenomena - 741.1 Light/Optics - 801 Chemistry - 801.4 Physical Chemistry - 802 Chemical Apparatus and Plants; Unit Operations; Unit Processes - 804.1 Organic Compounds - 815.1 Polymeric Materials - 931.3 Atomic and Molecular Physics - 951 Materials Science
Numerical data indexing:Percentage 2.50e+01%, Percentage 3.00e+01%, Time 2.16e+04s, Time 6.48e+04s
DOI:10.11975/j.issn.1002-6819.2018.03.038
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 12>
Accession number:20181605031878
Title:Field crop segmentation based on color coefficient reverse mutation particle swarm optimization algorithm
Authors:Xu, Yanlei (1, 2); Zhu, Chiyang (1); Li, Chenxiao (1); Zhang, Qi (1); Meng, Xiaotian (1); Wang, Xindong (1)
Author affiliation:(1) College of Information Technology, Jilin Agricultural University, Changchun; 130118, China; (2) Key Laboratory of Bionics Engineering, Ministry of Education, Jilin University, Changchun; 130025, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:173-179
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Image segmentation algorithm can effectively extract target information, thus providing an important precondition for the application of intelligent agriculture. How to retain the external features of field crops as well as meet the requirements of farmland work speed in a complicated and changeable farmland environment is one of the important problems to be solved in the current farmland image segmentation algorithm. At present, color segmentation method is the most commonly used one for field crop image segmentation. There are obvious color feature differences between crops and soils, so the most intuitional color information of the image can be used for effectively extracting information of the crops. However, the commonly used color model can keep the shape of the crop but can't meet the requirements of speed and different illuminations at the same time. In recent years, machine learning methods have been applied in the crop image segmentation in some studies to improve the traditional segmentation algorithms. Though these methods can segment field image more precisely in different light conditions, the algorithm results rely on a data training process which needs a long calculation time, so it is difficult for these methods to be applied in real-time work. Therefore, this paper proposes a field crop image segmentation method based on reverse mutation-particle swarm optimize (RM-PSO) algorithm to solve the mentioned above problem. This method is divided into offline and online parts. The optimal coefficients of color are obtained by training data samples offline. The coefficients can be used to segment field image in real time. The method proposed in this paper can improve the process speed. The paper focuses on offline part and puts forward a strategy of RM to improve the PSO algorithm by training sample data. Firstly, the reverse particles are generated from the initial ones by using the reverse space strategy, and we compare the fitness of the reverse particles with that of the initial ones to eliminate the particles of poor quality and construct a new initial particle swarm, thus improving particle diversity and the quality of initial particles. Secondly, when the evolutionary particles are in a passive state during the process of particle iteration, we mutate the passive particles to avoid premature convergence of the algorithm and running into local optimum. Thirdly, we introduce a satisfaction function to evaluate the optimal color coefficient of a single sample in the color searching space, and take the global optimal color coefficient as the final result. As for the online part, the images collected in real time will be processed with the global optimal color coefficient, the between-class variance of the processed gray-level images will be calculated with the automatic threshold segmentation method, and then the maximum between-class variance threshold will be used as the optimal one to obtain the segmenting images. By comparing this method with frequently-used color segmentation methods, the experimental result shows that under different light conditions and interference in different sceneries, the method in this paper can make crops maintain complete external feature while ensuring the processing speed. According to the statistical data of 30 test images, for the algorithm segmentation accuracy, the method in this paper has an average wrong segmentation ratio of 4.8%, which is lower than the HSI (hue, saturation, intensity) algorithm (11.3%), the excessive green algorithm (19.5%) and traditional PSO (7.6%); for the algorithm stability, the algorithm in this paper has a wrong segmentation ratio standard deviation of 3.1%, which is lower than the HSI algorithm (7.2%), the excessive green algorithm (14.7%) and traditional PSO (7.9%), so it is of higher reliability; for the processing speed, the method in this paper takes nearly the same processing time as the excessive green algorithm and traditional PSO, namely 0.311, 0.303 and 0.319 s respectively. Therefore, the method in this paper provides a reliable technology basis for field crop identification and possesses high practical application value.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Image segmentation
Controlled terms:Algorithms - Color - Color image processing - Crops - Farms - Image enhancement - Iterative methods - Learning systems - Particle swarm optimization (PSO) - Soils - Speed
Uncontrolled terms:Between-class variances - Extracting information - Image segmentation algorithm - Machine learning methods - Pre-mature convergences - Reverse mutation - Satisfaction functions - Segmentation algorithms
Classification code:483.1 Soils and Soil Mechanics - 723 Computer Software, Data Handling and Applications - 741.1 Light/Optics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4 Agricultural Products - 921.6 Numerical Methods
Numerical data indexing:Percentage 1.13e+01%, Percentage 1.47e+01%, Percentage 1.95e+01%, Percentage 3.10e+00%, Percentage 4.80e+00%, Percentage 7.20e+00%, Percentage 7.60e+00%, Percentage 7.90e+00%, Time 3.03e-01s, Time 3.19e-01s
DOI:10.11975/j.issn.1002-6819.2018.03.023
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 13>
Accession number:20181605031884
Title:Pretreatment by crude enzymatic liquid from Trichoderma harzianum and Aspergillus sp improving methane production performance during anaerobic digestion of straw
Authors:Zhao, Xiaoling (1); Zheng, Zehui (1); Cai, Yafan (1); Zhao, Yubin (1); Luo, Kai (1); Cui, Zongjun (1); Wang, Xiaofen (1)
Author affiliation:(1) College of Agronomy and Biotechnology, China Agricultural University, Beijing; 100193, China
Corresponding author:Wang, Xiaofen(wxiaofen@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:219-226
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to improve methane production from maize straw, crude enzymes from Trichoderma harzianum and Aspergillus sp. by solid-state fermentation were used to pretreat the maize straw before anaerobic fermentation. The experiment was divided into two parts: pretreatment and anaerobic digestion. Enzymatic treatments were done using enzymes (enzyme from Trichoderma harzianum, named as enzyme T; and enzyme from Aspergillus sp, named as enzyme A) inoculated into dry yellow maize straw at 50℃ for 6 days. The enzymes had the ability to hydrolyze cellulose and hemicellulose, and the CMCase and xylanase activity in enzyme T were (12.38 ± 0.69) and (230.53 ± 23.03) U/mL, from enzyme A were (3.32 ± 0.68) and (891.77±27.36) U/mL, respectively. Control samples (CK) were prepared using the same conditions as in enzymatic treatment, but with no enzyme added. Maize straw was pretreated for 6 days as the fermentation substrates and the sludge was inoculum. The working volume of each suction-flask reactor was 1 L, and 300 mL inoculum was loaded into each reactor. Batch tests were conducted in a walk-in incubation room for 20 days at (35±2)℃. Triplicate reactors were run for each condition. Inoculum without any added feedstock was used as a blank. The biogas production and methane composition were measured every day and the pH value, volatile fatty acids (VFA), soluble chemical oxygen demand (sCOD) and alkalinity were measured during the fermentation. The relationship between VFA and sCOD or VFA and alkalinity during anaerobic fermentation was analyzed. High-throughput sequencing was used to determine the microbial community structure in 24 hours fermentation samples, in order to detect the effect of enzymatic pretreatment and its impact on the bacteria and archaea community in anaerobic fermentation system. The results showed that VFA concentration increased significantly after treated by enzyme T and enzyme A, and mainly reflected in the accumulation of acetic acid content at 0 d. After 2 days fermentation, propionic acid was the main component of VFA. At the 1 day, the ratio of alkalinity/VFA and sCOD/VFA of enzyme T group and enzyme A group were significantly increased, which were 18.69 and 8.69 in enzyme T group, and 10.89 and 7.18 in enzyme A group, respectively. These changes were mainly due to the decrease of VFA. However, CK group in both alkalinity/VFA and sCOD/VFA showed a gradual decline trend. The cumulative methane yield by enzyme T group and enzyme A group were increased by 7.79% and 10.06%, respectively, compared with the control. After 24 hours fermentation, the abundance of 9 genus of bacteria in enzyme T group were increased than CK group, and Clostridium, vadinBC27 and Ruminofilibacter were related to the degradation of cellulose. The bacteria in enzyme A group was similar with CK group, and only 5 genus were significant difference. The main archaea were Methanosaeta, Bathyarchaeota, Methanosarcina, Deep sea Euryarchaeotic Group-DSEG and Methanobacterium. The pretreatment could affect the microbial structure in the fermentation system. Effective pretreatment plays an important role in anaerobic digestion of lignocellulose. This study provides important theoretical and technical support for the use of enzymes in methane production of agricultural wastes.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Volatile fatty acids
Controlled terms:Agricultural wastes - Alkalinity - Anaerobic digestion - Aspergillus - Bacteria - Biodegradation - Cellulose - Chemical oxygen demand - Enzyme activity - Enzymes - Fermentation - Liquid methane - Methane - Microorganisms - pH - Propionic acid
Uncontrolled terms:Aspergillus sp - Fermentation substrates - High-throughput sequencing - Microbial community structures - Pre-Treatment - Solid-state fermentation - Soluble chemical oxygen demands - Trichoderma harzianum
Classification code:461.8 Biotechnology - 461.9 Biology - 801.1 Chemistry, General - 801.2 Biochemistry - 804.1 Organic Compounds - 811.3 Cellulose, Lignin and Derivatives - 821.5 Agricultural Wastes
Numerical data indexing:Age 1.64e-02yr, Age 2.74e-03yr, Age 5.48e-02yr, Age 5.48e-03yr, Percentage 1.01e+01%, Percentage 7.79e+00%, Time 8.64e+04s, Volume 1.00e-03m3, Volume 3.00e-04m3
DOI:10.11975/j.issn.1002-6819.2018.03.029
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 14>
Accession number:20181605031888
Title:Analysis of influencing factors of farmers' participation behavior in different rural residential land consolidation stages
Authors:Li, Fanfan (1); Liu, Youzhao (1)
Author affiliation:(1) College of Public Administration, Nanjing Agricultural University, Nanjing; 210095, China
Corresponding author:Liu, Youzhao(yzliu@njau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:249-257
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:To promote farmers' participation in rural residential land consolidation, the research of discussing the mechanism of farmers' participation in rural residential land consolidation and identifying the factors affecting farmers' participation behavior should be carried out urgently. Specific mechanisms of some influence factors causingfarmers' different participation behaviors couldn't be explained well, when farmers' different participation behaviors in different consolidation stages were considered as an entire party. Therefore, based on rural residential land consolidation stages, farmers' participation behaviors were divided into 4 types in this paper: general participation, decision-making participation, construction participation and late management and protection participation. The questionnaire was designed to investigate farmerbasic information, farmers'different participation behaviors, and the environment of the villages. Toguarantee the representativeness of the sample, 3-4 resettlement areas, in which land consolidation had been completed, were chosen in every district/county. The total number of valid farmer questionnaires was 531 from2 cities innorth and south Jiangsu Province, which involved 25 villages in 5 districts/counties.From June to Augustin 2016, face-to-face investigations were conducted with farmers by random sampling. Based on the micro-survey data, binary logistic regression models by Stata12 were used to explore the influence factors of farmers' different participation behaviors in different rural residential land consolidation stages. The results indicated: 1) Farmers' cognition of consolidation content, health condition, government support and local economic level had significant impacts on farmers' general participation, while the factors like gender, education years, cognition of participation ability and social identity, which should significantlyaffect farmers' participation behaviors theoretically, exerted no significant influence in the model. 2) There were significant differences between the factors that significantly affected farmers' participation in different rural residential land consolidation stages. And factors such as gender, social identity and social relation network had significant effects on farmers' particular participationbehavior, but the effects were counteracted at general participation level. It was the reason why they had no significant effect on farmers' general participation behavior.This findingfully demonstrated the necessity of analyzing farmers' participation in different stages.3) Despite factors affectingfarmers' participation behavior in different stages differed, farmers' cognition of consolidation content, cognition of participation ability andgovernment supportinfluencedmost types of farmers' participation behaviors significantly.4) Family income and education yearshad no significant impact on any type of farmers' participation behavior.It implies that constraints brought by low family income and education level are no more the key factors that reduce farmers' participation motivation. Consciousness of rights will be the new incentive instead. And the awakening of consciousness of rights depends on the construction of the external systems and policies.According to these results, it issuggested that differential policies should be made to encourage farmers participating in the entire consolidation process. Enhancing farmers' ability to participate, improving participation process andconstructing external institutional environment should be the priorities of policy-making in the foreseeable future. This study can provide amore comprehensive and accurate guidance for promoting farmers' participation in rural residential land consolidation.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Agriculture
Controlled terms:Decision making - Housing - Land use - Regression analysis - Rural areas - Surveys
Uncontrolled terms:Binary logistic regression models - Consolidation process - Consolidation stages - Farmers' participation behavior - Government supports - Influencing factors - Jiangsu province - Rural regions
Classification code:403 Urban and Regional Planning and Development - 403.1 Urban Planning and Development - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 912.2 Management - 922.2 Mathematical Statistics
DOI:10.11975/j.issn.1002-6819.2018.03.033
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 15>
Accession number:20181605031875
Title:Effects of self-sown grass on soil moisture and tree growth in apple orchard on Weibei dry plateau
Authors:Bai, Gangshuan (1, 2); Zou, Chaoyu (3); Du, She'ni (1, 2)
Author affiliation:(1) Institute of Soil and Water Conservation, Northwest A & F University, Yangling; 712100, China; (2) Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling; 712100, China; (3) Shenzhen Techand Ecology & Environment Co. Ltd., Shenzhen; 518040, China
Corresponding author:Du, She'ni(sndu@nwsuaf.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:151-158
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The Weibei plateau is one of the most productive regions of apples in China and also in the world. However, annual precipitation in this region is limited and is unevenly distributed over seasons. The deficiency of soil moisture has been the main factor to restrict the production of high-quality apples in the Weibei plateau. Although artificial-planted grass could improve soil organic matter and soil micro-environment, it could also induce competitions of soil moisture and nutrients with fruit trees and further inhibit fruit tree growth and consequently reducing apple yields and quality. On the contrary, self-sown grass has experienced many years of natural selection, more capable of adapting to local ecological environment, which is very likely to improve orchard soil environment and even promote a virtuous cycle in orchard ecosystem. However, there has been quite limited investigation on the potential influence of self-sown grass on soil moisture and apple tree growth in the region of Weibei plateau. Therefore, in this study, self-sown grass, chickweed (Stellaria media) and cattle chickweed (Malachium aquaticum), were systematically investigated in Weibei plateau, and with artificial-planted grass, white clover (Trifolium repens) and clean tillage as control. The soil water storage, evapotranspiration, single fruit weight, fruit yields and other relevant parameters were continuously monitored. The results showed that the coverage of the self-sown grass were greater than that of the artificial-planted grass, but the height, aboveground biomass, roots biomass, roots depth and the ratio of roots biomass to aboveground biomass were significantly lower (P<0.05) with the self-sown grass than those with the artificial-planted grass. In addition, self-sown grass and artificial-planted grass mainly affected the soil water storage at depth of 0-80 cm, especially at soil depth above 40 cm. Their influences to soil layers deeper than 120 cm were fairly limited. To be more specific, while the soil water storage at soil depth of 0-80 cm on the self-sown grass orchard increased in flowering and fruit-bearing stage, it decreased on the artificial-planted grass orchard throughout the entire growing stages. For the soil depth of 0-120 cm on the self-sown grass orchard, the soil water storage increased in young fruit enlargement stage and flower bud differentiation stage. Similarly, the soil water storage at soil depth of 0-160 cm also increased on the self-sown grass orchard during fruit enlargement stage before harvesting. The soil water storage of the artificial-planted grass orchard recovered slowly in rainy season (from August to October), and was also lower than that of the clean tillage orchard and the self-sown grass orchard, this would negatively affect fruit enlargement before harvesting, therefore reducing fruit yields, and even further inhabiting flowering and fruit-bearing and the growth of new shoots in the coming year. As to the differences of soil evapotranspiration, the self-sown grass orchard highly significantly reduced the orchard evapotranspiration in April and May (P<0.01), and significantly in August (P<0.05). This would potentially contribute to young fruit enlargement and fruit enlargement before harvesting. Although the precipitation of experiment year was higher than the long-term average annual precipitation, evapotranspiration of the artificial-planted grass orchard and clean tillage orchard were still greater than the precipitation that occurred at the same period by 32.55 and 23.32 mm. Meanwhile, the soil evapotranspiration on the self-sown grass orchard was only were 15.25 mm more than the precipitation occurred at the same period. Among the different grass orchards, the amount of evapotranspiration from the self-sown grass orchard decreased by 17.30 and 8.07 mm when compared with that of the artificial-planted grass orchard and clear tillage orchard. Our results indicated that self-sown grass could effectively alleviate soil water storage shortage in the apple orchard on the Weibei plateau. The apple shoots and branch tapering grade with self-sown grass were more vigorous than that with the artificial-planted grass and clean tillage. Compared with the artificial-planted grass and clean tillage, the single fruit weight of the self-sown grass increased by 15.46% and 6.21%, the fruit yields improved by 21.29% and 6.10%, and soil water use efficiency enhanced by 25.09% and 7.64%. The self-sown grass could not only improve orchard soil moisture, but could also stimulate shoots growth and further improve fruit quality and fruit yields. Therefore, the self-sown grass should be extensively promoted in the Weibei plateau.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:44
Main heading:Orchards
Controlled terms:Agricultural machinery - Biomass - Ecology - Evapotranspiration - Forestry - Fruits - Harvesting - Moisture - Soil moisture - Soils - Water supply
Uncontrolled terms:Above ground biomass - Artificial-planted grass - Average annual precipitation - Ecological environments - Flower bud differentiations - Self-sown grass - Soil organic matters - Weibei dry plateau
Classification code:446.1 Water Supply Systems - 454.3 Ecology and Ecosystems - 483.1 Soils and Soil Mechanics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
Numerical data indexing:Percentage 1.55e+01%, Percentage 2.13e+01%, Percentage 2.51e+01%, Percentage 6.10e+00%, Percentage 6.21e+00%, Percentage 7.64e+00%, Size 0.00e+00m to 1.20e+00m, Size 0.00e+00m to 1.60e+00m, Size 0.00e+00m to 8.00e-01m, Size 1.20e+00m, Size 1.52e-02m, Size 1.73e-02m, Size 2.33e-02m, Size 3.25e-02m, Size 4.00e-01m, Size 8.07e-03m
DOI:10.11975/j.issn.1002-6819.2018.03.020
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 16>
Accession number:20181605031881
Title:Estimation model of LAI and nitrogen content in tea tree based on hyperspectral image
Authors:Wu, Weibin (1); Li, Jiayu (2); Zhang, Zhenbang (1); Ling, Caijin (3); Lin, Xianke (4); Chang, Xingliang (1)
Author affiliation:(1) College of Engineering, South China Agricultural University, Guangzhou; 510642, China; (2) College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou; 510642, China; (3) Tea Research Institute, Guangdong Academy of Agricultural Science, Guangzhou; 510642, China; (4) College of Natural Resources and Environment, South China Agricultural University, Guangzhou; 510642, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:195-201
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Leaf area index (LAI), the total area of plant leaves on the unit land area, is an important vegetation characteristic of plant canopy, which can reflect the growth status of vegetation. The effective detection of leaf nitrogen, a significant chemical element which could promote the growth of plant leaves, is beneficial to the precision fertilization and nutrient management of tea plantations, while it is also of great importance to the improve of quality and yield of tea leaves. In order to improve the production of Yinhong 9th tea, rational fertilization and protect the tea garden ecological environment, in this study, we used hyperspectral nondestructive testing technology to detect the LAI and nitrogen content with hyperspectral camera. Nitrogen is an important element that makes up tea chlorophyll, its content directly affects the synthesis of organic matter in tea tree, and it can affect leaf area index. Therefore, leaf area index and nitrogen content have certain correlation. At present, information on research of plant leaf area index for hyperspectral detection is limited. By using hyperspectral inversion tea nondestructive detection of two parameters, it can solve the problem of tea plant nutrition diagnosis, which may has positive impact on quality of the Yinhong 9th tea. Although the detection of nitrogen content of leaf is direct and accurate using the traditional chemical method, its complex operation, sample damaging and incapable to detect large area orchard in real-time, fast and nondestructive make it not the best method. To achieve real-time, fast and nondestructive detection of leaf area index (LAI) and nitrogen content of tea leaves, in this paper, a portable hyperspectral imager had been used to gather spectral data. Destructive leaf picking had been used to calculate leaf area index and traditional chemical method had been used to calculate the leaf nitrogen content. Using the Yinghong 9th tea tree as test subject, correlation analysis was done among hyperspectral characteristic variable data, LAI and leaf nitrogen content. Estimated model was built using high relevant hyperspectral characteristic parameter data, LAI and nitrogen content by linear, index, logarithm, parabola and etc. After that, evaluation of model performance and model accuracy test by root mean square error (RMSE) were conducted. After comparing different transformation of spectral data between the correlation of LAI and nitrogen content, the pretreated spectral parameters were used as independent variables to build the regression model of LAI and nitrogen content, respectively. The results showed that the logarithmic optimal fitting model was built between Green peak reflectance R<inf>g</inf>and leaf area index, from which the regression coefficient value R<sup>2</sup>and test samples RMSE value was 0.9 and 0.087 6, respectively, while the best modeling result was the model built between vegetation index VI<inf>4</inf>and the nitrogen content, from which the regression coefficient value R<sup>2</sup>and test samples RMSE value was 0.830 3 and 0.102 9, respectively. According to the result above, a better estimated model was developed using LAI detected by traditional chemical method, nitrogen content and hyperspectral data, which produced the theoretical basis for fast and nondestructive detection of LAI and nitrogen content of tea leaves in the possible future. However, sample process and modeling comparison of different growing season had not been done. The further research should be continued to study the relationship between LAI and the nutritional status, growth index and nutrient management of tea tree in different cultivation measures and ecological conditions. These results can provide reference for the nondestructive detection of LAI and the nutrient component of tea tree.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Nitrogen
Controlled terms:Chemical detection - Crops - Cultivation - Ecology - Hyperspectral imaging - Mean square error - Metadata - Models - Nondestructive examination - Nutrients - Nutrition - Regression analysis - Spectroscopy - Vegetation
Uncontrolled terms:Hyper-spectral characteristics - Hyperspectral detections - Leaf Area Index - Non destructive testing - Nondestructive detection - Precision fertilizations - Root mean square errors - Tea canopy
Classification code:454.3 Ecology and Ecosystems - 461.7 Health Care - 801 Chemistry - 804 Chemical Products Generally - 821.3 Agricultural Methods - 821.4 Agricultural Products - 922.2 Mathematical Statistics
DOI:10.11975/j.issn.1002-6819.2018.03.026
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 17>
Accession number:20181605031886
Title:Influence of feeding density of ducks in rice field on movement behaviour and weeds control
Authors:Zhang, Benhua (1); Zhang, Yuhong (1); Kong, Aiju (1); Song, Yuqiu (1); Wu, Liyan (1); Xin, Mingjin (1); Liu, Cuihong (1); Cui, Hongguang (1); Ren, Wentao (1)
Author affiliation:(1) College of Engineering, Shenyang Agricultural University, Shenyang; 110886, China
Corresponding author:Ren, Wentao(rwt@syau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:234-239
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The location information of ducks in paddy field is necessary in order to adequately explore the behavioral activities of ducks in the field and the control effect on weeds. Satellite and wireless positioning systems are difficult to adapt well in rice-duck field condition, however, ultra wide band (UWB) positioning technique is a good alternative and can adapt effectively. In this study, the use of UWB positioning system to detect the movement location information of ducks in rice field was reported. The system uses DW1000 positioning chip to build the base station with detection accuracy of 10 cm. Each tagged duck position coordinates (x, y) were computed based on TDOA (time difference of arrival) location algorithm and passed through the API (application programming interface) interface. The treatment monitoring plot area was 660 m<sup>2</sup>(11 m×60 m rectangular plot). 6 base stations were established and each station was fixed to each of the 4 vertices of the rectangle and midpoint of the long side. Ducks activities in the field under different conditions of release density (15, 20, 25 and 30) were studied. Experimental condition of each duck density was the same and location information were collected every other 2 days. Results showed that with increase of release density, the ducks became more active. Also, the state of ducks mobility in the field gradually increased as the density increased. Corresponding to the stocking density of 15, 20, 25 and 30, the proportion of total time obtained were 69.17%, 75.33%, 77.83% and 80.00%, respectively. More ducks were found to enter into each unit cell area as the release density increased. The number of entrance corresponding to the density of 15, 20, 25 and 30 were obtained as 12.05, 17.82, 23.03 and 27.73 times, respectively. Ducklings entering cells at low frequency (1-3 times per day) had the greatest probability. But, with increase in release density, the probability to enter at high frequency (7-13 times) also increased rapidly. The control effect on weeds was found to be much better when the feeding density was high. However, the purpose of duck's field activities was to get food, therefore, the larger the stocking density, the more competition for food. Accordingly, the more time ducks were in the field, and the frequency of entering into each unit cell, the more opportunities for weeding. The research results therefore will provide a reference for the further optimization of the technical process of duck rice.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Ultra-wideband (UWB)
Controlled terms:Animals - Application programming interfaces (API) - Base stations - Broadband networks - Crops - Feeding - Location - Time difference of arrival - Weed control
Uncontrolled terms:Experimental conditions - Location information - Position coordinates - Positioning system - Positioning techniques - Rice duck farming - Treatment monitoring - Wireless positioning systems
Classification code:691.2 Materials Handling Methods - 716.3 Radio Systems and Equipment - 723 Computer Software, Data Handling and Applications - 821.4 Agricultural Products
Numerical data indexing:Age 5.48e-03yr, Percentage 6.92e+01%, Percentage 7.53e+01%, Percentage 7.78e+01%, Percentage 8.00e+01%, Size 1.00e-01m
DOI:10.11975/j.issn.1002-6819.2018.03.031
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 18>
Accession number:20181605031864
Title:Improvement of wear resistance of deep-shovel tip with Fe-based alloy coating by flame spray welding residual temperature quenching
Authors:Zhao, Jianguo (1); Li, Jianchang (1); Wang, An (1); Ma, Luping (1); Hao, Jianjun (1); Zhang, Jinguo (1); Ma, Yuejin (1)
Author affiliation:(1) College of Mechanical and Electrical Engineering, Hebei Agricultural University, Baoding; 071001, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:65-71
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:There is a problem that subsoiling shovel tips are poor in wear resistance and lose effectiveness frequently. In order to solve the problems of poor wear resistance and frequent failure, Fe-Cr-Ni alloy coating was prepared on 45 steel substrate using flame spray welding process. And the spray welding coating has been quenched using the specimen residual temperature. The quenching temperature is 800 ℃. Microstructure, composition and phase of alloy coating were analyzed by scanning electron microscope, energy dispersive spectrometer, and X-ray diffraction. The microhardness was tested by microhardness tester. The wear properties were tested by soil abrasive wear testing machine. The results showed that the coating zone, binding zone and substrate zone are obvious, metal interpenetration phenomenon has been found in binding zone, and metallurgical bonding can be achieved between the coating and substrate. The good metallurgical bonding can be obtained between the coating and iron substrate. The alloy coating consists of carbide Cr<inf>7</inf>C<inf>3</inf>and Cr<inf>23</inf>C<inf>6</inf>, boride Fe<inf>2</inf>B, (Cr, Fe)<inf>7</inf>C<inf>3</inf>and solid solution γ-Fe(Cr, Ni, C, Si) and (Fe, Ni). On the effect of oxygen and acetylene hot resource, Fe and Cr elements in the alloy were heated to molten state, and then Fe, Cr and C, B were combined to form carbide and boride. As the role of the austenite stable element Ni, there is γ-Fe (Cr, Ni, C, Si) solid solution formed in the coating, which is helpful to reduce the brittleness of the spray welding layer. Compared with the unquenched coating, the microstructure of quenched coating is refined, and the hard phase is shown as rectangular block, lozenge block and ball block, whose size is from 5 to 20 μm. The microhardness of the quenched coating can reach up to 900 HV, and the average microhardness is about 800 HV, increased by about 100 HV compared with the unquenched coating. The contrast tests have been carried out between quenched coating, unquenched coating and 65 Mn subsoiling shovel tip. The average wear loss of quenched coating is about 0.30 g, that of the unquenched coating is about 0.35 g, and the average wear loss of 65 Mn subsoiling shovel tip is about 0.50 g, about 2 times as much as the quenched coating. After carrying out field test, the wear loss of subsoiling shovel tip with quenched coating is 32 g, and 65 Mn subsoiling shovel tip is 70 g. As shock cooling effect of quenching, alloy elements transfer is difficult, which is not conducive to the growth of carbide. As a result, the carbides are refined. Furthermore, supersaturated solid solution of carbon is formed owing to diffusion failure of some carbon elements. The supersaturated solid solution leads to the increase of dislocation density, the lattice distortion, and the hardness increase. The dispersion distribution of hard phase Cr<inf>7</inf>C<inf>3</inf>, (Cr, Fe)<inf>7</inf>C<inf>3</inf>, Cr<inf>23</inf>C<inf>6</inf>and Fe<inf>2</inf>B is obtained on the softer substrate. The hard phase plays a role of increasing the energy consumption of the abrasive, and reducing the cutting and ploughing effect of abrasive grains on the coating surface. The hard phase, supersaturated solid solution and Fe, Ni have been fused together, showing alternate distribution. The substrate metal with good toughness has good bonding effect on hard phase. There is good wear resistance for quenched coating. The spray welding coating has been quenched using the coating residual temperature successfully. The cost of quenching process is low and the efficiency is high. The process is convenient and flexible, which can meet the needs of the subsoiling shovel surface strengthening and practical application.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Chromium alloys
Controlled terms:Abrasives - Agricultural machinery - Binding energy - Borides - Carbides - Carbon - Coatings - Concrete beams and girders - Energy utilization - Flame resistance - Flame spraying - Fracture mechanics - Iron alloys - Manganese - Metal cladding - Microhardness - Microstructure - Nickel alloys - Quenching - Scanning electron microscopy - Shovels - Soil testing - Solid solutions - Spectrometers - Spray guns - Ternary alloys - Wear of materials - Wear resistance - Welding - X ray diffraction
Uncontrolled terms:Deep-shovel tip - Dislocation densities - Dispersion distributions - Energy dispersive spectrometers - Fe-Cr-Ni alloys - Quenching temperatures - Supersaturated solid solutions - Surface strengthening
Classification code:412 Concrete - 483.1 Soils and Soil Mechanics - 525.3 Energy Utilization - 537.1 Heat Treatment Processes - 538.2 Welding - 543.1 Chromium and Alloys - 543.2 Manganese and Alloys - 545.2 Iron Alloys - 548.2 Nickel Alloys - 606.1 Abrasive Materials - 741.3 Optical Devices and Systems - 801.4 Physical Chemistry - 804 Chemical Products Generally - 804.2 Inorganic Compounds - 813.1 Coating Techniques - 813.2 Coating Materials - 821.1 Agricultural Machinery and Equipment - 914.2 Fires and Fire Protection - 931.1 Mechanics - 931.2 Physical Properties of Gases, Liquids and Solids - 933 Solid State Physics - 951 Materials Science
Numerical data indexing:Mass 3.00e-04kg, Mass 3.20e-02kg, Mass 3.50e-04kg, Mass 5.00e-04kg, Mass 7.00e-02kg, Size 5.00e-06m to 2.00e-05m
DOI:10.11975/j.issn.1002-6819.2018.03.009
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 19>
Accession number:20181605031889
Title:Suitability evaluation of urban land development based on niche and anti-planning
Authors:Zhang, Rongqun (1); Wang, Dahai (1); Ai, Dong (2); Sun, Weijian (1); Hou, Zhenyu (3)
Author affiliation:(1) College of Information and Electrical Engineering, China Agricultural University, Beijing; 100083, China; (2) College of Resources and Environmental Sciences, China Agricultural University, Beijing; 100193, China; (3) Ministry of Agriculture, Cultivated Land Quality Monitoring and Protection Center, Beijing; 100125, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:258-264
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The evaluation of urban land development suitability is of great significance to the overall planning of urban land use. In order to know more about the suitability of urban land development, this study put forward the concept of urban land niche, and constructed the niche suitability model of urban land according to the urban land real ecology degree and the most suitable niche. The evaluation factor system of the model was constructed by referring to the anti-planning idea of giving priority to controlling the construction area. The evaluation factor system was divided into strong restrictive factor and stronger restrictive factor. The optimal value of urban land evaluation factor was influenced by multiple factors. The realistic resource niche of urban land in the study area was taken into account, and combined with relevant historical documents, the corresponding score was given for each evaluation factor. The strong restrictive factor was assigned with 0 and 1. And the stronger restrictive factor was assigned the values using the expert scoring method. And the score 100 was regarded as its optimal value. Considering the slope transition point of urban land niche suitability distribution curve, combined with the natural break-point method, based on the relevant historical literature, the urban land development suitability of the study area was divided into 4 grades: the first grade (the most suitability), the second grade (basic suitability), the third grade (not suitable), and the fourth grade (especially unsuitable). Finally, based on the urban land ecological suitability, this paper divided the suitability of urban land comprehensive development in Fangshan District, Beijing City, and evaluated from the 3 aspects i.e. the plain area, the shallow mountain area and the deep mountain area. The results were as follows: 1) The first grade area is 2 645.93 hm<sup>2</sup>, accounting for 13.27% of the total area; the second grade area is 1 697.79 hm<sup>2</sup>, accounting for 8.52% of the total area; the third grade area is 11 533.68 hm<sup>2</sup>, accounting for 57.86% of the total area; and the fourth grade area is 4 057.77 hm<sup>2</sup>, accounting for 20.35% of the total area. 2) The ecological suitability of urban land in the study area is ladder-like on the whole, and the land development suitability is gradually increasing from west to east. 3) In the plain area, the most suitable area of urban land development is the most, and the deep mountainous areas and shallow mountainous areas are mostly inappropriate areas and particularly unsuitable areas. 4) The deep mountainous areas and shallow mountainous areas are affected by the factors such as ecological control and mining subsidence. The evaluation of the suitability of urban land comprehensive development was made by using niche suitability model and anti-planning idea, which enriches the application field of anti-planning and niche theory.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:35
Main heading:Landforms
Controlled terms:Cutting machines (mining) - Ecology - Land use - Optimal systems - Zoning
Uncontrolled terms:Distribution curves - Ecological suitability - Historical documents - Land consolidations - Land development - Niche - Shallow mountain areas - Suitability evaluation
Classification code:403 Urban and Regional Planning and Development - 454.3 Ecology and Ecosystems - 481.1 Geology - 502.2 Mine and Quarry Equipment - 961 Systems Science
Numerical data indexing:Percentage 1.33e+01%, Percentage 2.04e+01%, Percentage 5.79e+01%, Percentage 8.52e+00%
DOI:10.11975/j.issn.1002-6819.2018.03.034
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 20>
Accession number:20181605031896
Title:Removal processing optimization of flaxseed mucilage and its improved effect on extraction rate of flaxseed oil
Authors:Sun, Hong (1); Zhang, Wenbin (1, 2); Yang, Ruijin (1, 2); Hua, Xiao (1, 2); Zhao, Wei (1, 2)
Author affiliation:(1) State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi; 214122, China; (2) School of Food Science and Technology, Jiangnan University, Wuxi; 214122, China
Corresponding author:Zhang, Wenbin(wbzhang@jiangnan.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:309-314
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Flaxseed, which is also called linseed, is an kind of important oilseed in the world. The nutritional components of flaxseed are oil, protein, lignans, soluble fiber, minerals, and vitamin, and so onetc. It is known as the richest source of the n-3 fatty acid, alpha linolenic acid (n-3 fatty acid), which comprises approximately 55% of the total fatty acids, and this percentage is 5.5 times higher than that in the second next-highest sources. Flaxseed plays an important role in functional foods for its nutritional and pharmaceutical values. In recent years, aqueous enzymatic extraction, an emerging alternative to hexane-based oilseed extraction regarding product safety and simultaneous recovery of high quality protein products and high yield of vegetable oils has drawn increasing attentions over decades. However, due to the high water-holding capacities, stabilization and emulsification properties of flaxseed mucilage, extraction and separation of flaxseed oil from raw flaxseed by aqueous enzymatic method are proved to be inefficient and even prohibitive. In order to improve the yield of flaxseed oil extracted by aqueous enzymatic method, the effect of demucilage on the aqueous enzymatic extraction of flaxseed oil was investigated by comparing the yield of flaxseed oil before and after removal of flaxseed mucilage through hot water extraction. Results showed that the mucilage on the surface of flaxseed significantly impeded the separation of oil from aqueous enzymatic extraction system, thus resulting in a low extraction yield of flaxseed oil. More specifically, the oil yield of raw flaxseed was only 69.20%±1.51% and residual oil content in insoluble phase was 26.00%±1.24%, while after removal of 94.69%±1.94% mucilage by hot water extraction treatment at 100℃ (the removal rate of 94.69%±1.94%), the yield of flaxseed oil significantly increased to 84.26%±0.63% and residual oil content in insoluble phase decreased to 10.45%±0.89%. Mucilage removal conditions were optimized by single-factor experiments and the optimal conditions were obtained as follows: eExtraction temperature was 85℃, pH value was 3, flaxseed-to-water ratio was 1: 7 g/mL, extraction time was 60 min and extraction was repeated twice. Under the optimum conditions, the mucilage removal efficiency was 97.88%±0.69%, the yield of the flaxseed oil reached to 84.47%±0.53%, and the loss ratios of flaxseed oil and protein were 0.70%±0.16% and 10.78%±0.41%, respectively. Acid value and peroxide value of the flaxseed oil before and after demucilage by hot water extraction treatment were determined and it was found that the demucilage process had no obvious influence on the quality of flaxseed oil extracted by aqueous enzymatic method. In addition, after the hot water extraction process, the content of cyanogenic glycosides in flaxseed was significantly decreased from 242.6±0.8 mg/kg to 7.1±0.6 mg/kg. The proposed flaxseed demucilage-method was simple and efficient, which not only significantly improved the yield of flaxseed oil with aqueous enzymatic method, but also laid a good foundation for preparation of flaxseed gum from the extract and further utilization of the flaxseed meal. Therefore, it presentsed a promising technology for the comprehensive utilization of flaxseed on industrial scale.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:35
Main heading:Extraction
Controlled terms:Adhesives - Emulsification - Fatty acids - Flax - Food safety - Oils and fats - Oilseeds - Optimization - Pressing (forming) - Processing - Proteins - Sugars - Water - Water treatment
Uncontrolled terms:Aqueous enzymatic extraction - Comprehensive utilizations - Cyanogenic glycosides - Emulsification properties - Flaxseed - Flaxseed oil - Mucilage - Single-factor experiments
Classification code:445.1 Water Treatment Techniques - 461.6 Medicine and Pharmacology - 802.3 Chemical Operations - 804.1 Organic Compounds - 819.1 Natural Fibers - 821.4 Agricultural Products - 913.4 Manufacturing - 921.5 Optimization Techniques
Numerical data indexing:Mass_Density 7.00e+03kg/m3, Percentage 5.50e+01%, Time 3.60e+03s
DOI:10.11975/j.issn.1002-6819.2018.03.041
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 21>
Accession number:20181605031870
Title:Analyzing representativeness of monitoring units for pollutant removal in agricultural drainage ditch-pond systems
Authors:Jia, Zhonghua (1); Chen, Cheng (1); Luo, Wan (1); Sun, Shaojiang (1); Zou, Jiarong (1); Wu, Wang (1); Zhang, Zhixiu (2); Zhu, Weibin (3)
Author affiliation:(1) College of Water Resources and Hydro-Power Engineering, Yangzhou University, Yangzhou; 225009, China; (2) Administrative Office of Yanyun Irrigated Area in Jiangdu District, Yangzhou; 225261, China; (3) River Management Department of Jiangdu District, Yangzhou; 225200, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:110-117
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to decide the pollutant removal ability of ditches and ponds in agricultural regions, it is often required to monitor the flow and pollutant dynamics. Differing from lab and pilot study settings in which the inflow and outflow can be managed and measured, the field ditches and ponds may not have single inlet and outlet clearly defined. Since it is difficult to monitor all ditch-pond segments due to technical and labor costs, a monitoring unit (MU) covering a fraction of the system may be used to deduce the system performance. To obtain a reasonable system estimation, a pre-requisite of MU is that it has to be representative, otherwise the overall performance of the system deduced from a partial MU will be erroneous. The mixed distribution of drainage ditches and ponds with crop fields causes the variation in pollutant removal among different segments, and this can affect the representativeness of MUs consisting of one or several segments. It is affected by the distribution, area and hydraulic connections of ditches and ponds, as well as pollutant degradation properties. This paper is based on a case study in Zhaoguan Irrigation District along the Grand Canal in the Jiangdu District of Yangzhou, China (119°25'E, 32°22'N). In the study area, the drainage ditch-pond system covers an area of 0.80 hm<sup>2</sup>, including 10 smaller field ditches covering an area of 0.09 hm<sup>2</sup>, 6 bigger branch ditches and 2 ponds. The total crop field is 5.61 hm<sup>2</sup>; and the areal ratio of ditch-pond to crop field was 14.3%. Previous investigation has shown that the pollutant removal in such field conditions was affected by ditch-pond distribution, area and hydraulic relationship. This paper investigated the representativeness of selected MUs and the factors for 2 most commonly used system evaluation indices: pollutant removal rate and intensity. Methods to evaluate and improve the representativeness of different MU compositions were proposed for pollutants with different degradation properties. The results indicated that the majority of segments could not represent the system adequately; while a particular monitoring unit could have excellent representativeness of one index, it could have rather poor representativeness of the other index. The overall segment removal intensity ratio was larger than 1, while the removal rate ratio was smaller than 1. For an intermediate pollutant degradation (degradation coefficient was 0.05 m/d), the removal intensity ratio was 1.54, and the removal rate ratio was 0.59, suggesting that using a single segment as MU will result in more than 50% overestimation of pollutant removal ability, while more than 40% underestimation of pollutant removal rate. The representativeness was affected by pollutant degradation properties and hydraulic retention time. The ratio of removal intensity had positive correlation with the hydraulic retention time while the ratio of removal rate had negative correlation with the hydraulic retention time. When degradation coefficient was between 0.01 and 0.10 m/d, the removal intensity ratio and the removal rate ratio for Drainage path 1 were 1.28-1.14 and 1.21-1.16, respectively. As for Drainage path 3, the 2 values were 0.84-0.94 and 1.27-1.33, respectively. Considering the amount of monitoring work, Drainage path 3 (Branch ditch 5) was better selected as the monitoring unit. The selection of MUs will be more forgiving for lower degradable pollutants, and bigger segments are generally better selection than smaller ones. For pollutant removal intensity, the selection of MUs can be more forgiving for low degradable pollutants; and for higher degradable pollutants, smaller segments should be avoided. For pollutant removal rates, smaller segments should be avoided, and it was recommended that the segments located at the middle stream should be selected. For the conditions when drainage paths, fields and pond/ditch segments were distributed unevenly, drainage paths with large volume should be considered as the monitoring unit and small drainage paths should be avoided. For the areas with multiple drainage paths, the segments with larger flow should be selected as the MUs, and the segments with disproportional ratios of ditch-pond to crop field should be avoided.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:35
Main heading:Pollution detection
Controlled terms:Crops - Drainage - Lakes - Monitoring - Ponds - Storm sewers - Wages - Wetlands
Uncontrolled terms:Agricultural drainage - Degradation coefficients - Field - Hydraulic retention time - Pollutant degradation - Pollutant removal - Positive correlations - Representativeness
Classification code:452.1 Sewage - 454.3 Ecology and Ecosystems - 821.4 Agricultural Products - 912.4 Personnel
Numerical data indexing:Percentage 1.43e+01%, Percentage 4.00e+01%, Percentage 5.00e+01%
DOI:10.11975/j.issn.1002-6819.2018.03.015
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 22>
Accession number:20181605031857
Title:Design and experiment of vertical circular separating and conveying device for potato combine harvester
Authors:Yang, Ranbing (1, 2); Yang, Hongguang (1); Shang, Shuqi (1, 2); Ni, Zhiwei (1); Liu, Zhishen (1); Guo, Dong (1)
Author affiliation:(1) College of Mechanical and Electrical Engineering, Qingdao Agricultural University, Qingdao; 266109, China; (2) Shandong Provincial Engineering Technology Research Center for Root Crops Production Equipment, Qingdao; 266109, China
Corresponding author:Shang, Shuqi(sqshang@qau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:10-18
Language:English
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:To solve the problems of the separating and conveying device for the potato combine harvester, such as poor separation and inflexibility of manipulation, a vertical circular separating and conveying device was designed. The structure and working parameters of key components of the separating and conveying device were determined by research analysis. Quadratic general rotation-combination experiments were carried out with the moving forward speed, the linear speed of the transverse transfer belt and the rotational speed of the circular orbit as experimental factors, damage rate and impurity rate as experimental index. The mathematical model of the relationship between the experimental factors and the experimental index were established and the parameters were optimized using DPS (data processing system) and Matlab (matrix laboratory) software. The results showed that the influences on the damage rate of the respective factors decrease in the order as below, the rotational speed of the circular orbit, the linear speed of the transverse transfer belt and the moving forward speed, the influences on the impurity rate of the respective factors decrease in the order as below, the rotational speed of the circular orbit, the moving forward speed and the linear speed of the transverse transfer belt. And the moving forward speed of 1.1 m/s, the linear speed of the transverse transfer belt of 1.5 m/s and the rotational speed of the circular orbit of 7 r/min were the best combination factors, which leaded to the damage rate of 1.28%, the impurity rate of 2.41%. Verification experiment results showed that the average damage rate of 1.46% and the average impurity rate of 2.57%, under the condition of optimal parameters, the theoretical value is similar to the test value, and its meet the relevant requirements of the potato combine harvest. This research can provide a technical basis and reference for the development of a new separating and conveying device and potato combine harvester.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Speed
Controlled terms:Data handling - Design - Experiments - Harvesters - MATLAB - Mechanization - Optimization - Separation
Uncontrolled terms:Combine harvesters - Damage rate - Data processing systems - Experimental factors - Impurity rates - Separating and conveying device - Structure and working parameters - Verification experiments
Classification code:601 Mechanical Design - 723.2 Data Processing and Image Processing - 802.3 Chemical Operations - 821.1 Agricultural Machinery and Equipment - 901.3 Engineering Research - 921 Mathematics - 921.5 Optimization Techniques
Numerical data indexing:Percentage 1.28e+00%, Percentage 1.46e+00%, Percentage 2.41e+00%, Percentage 2.57e+00%, Rotational_Speed 7.00e+00RPM, Velocity 1.10e+00m/s, Velocity 1.50e+00m/s
DOI:10.11975/j.issn.1002-6819.2018.03.002
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 23>
Accession number:20181605031874
Title:Effect of water deficit on photosynthetic characteristics, yield and water use efficiency in Shiranui citrus under drip irrigation
Authors:Zhang, Xiaoxing (1); Fan, Yi (2); Jia, Yue (3); Cui, Ningbo (1, 4); Zhao, Lu (1); Hu, Xiaotao (5); Gong, Daozhi (6)
Author affiliation:(1) State Key Laboratory of Hydraulics and Mountain River Engineering & College of Water Resource and Hydropower, Sichuan University, Chengdu; 610065, China; (2) Sichuan Provincial Water Conservancy Research Institute, Chengdu; 610072, China; (3) Hebei University of Water Resources and Electric Engineering, Cangzhou; 061001, China; (4) Provincial Key Laboratory of Water-Saving Agriculture in Hill Areas of Southern China, Chengdu; 610066, China; (5) Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas, Ministry of Education, Northwest A&F University/Institue of Water Saving Agriculture in Arid Areas of China, Yangling; 712100, China; (6) State Engineering Laboratory for Efficient Water Use and Disaster Loss Reduction of Crops, Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agriculture Science, Beijing; 100081, China
Corresponding author:Cui, Ningbo(cuiningbo@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:143-150
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Citrus is one of main fruits in China and it yield is unstable due to seasonal drought in recent years. It is important to understand the mechanisms behind the citrus tree growth under the drought stress. In this study, we investigated the effect of water deficit on photosynthetic characteristics, fruit yield and water use efficiency under drip irrigation. The orchard was located in Chendu, Sichuan. The tree was 7-year-old Shiranui citrus. The average tree height was about 2.8-3.0 m and the diameter of the tree was about 10 cm. A total of 4 water deficit treatments were designed in 2 growing stage of citrus (fruit expansion stage (III) and fruit maturity stage (IV)). Meanwhile, the treatment without water deficit was considered as the control with 100% irrigation amount. The 4 water deficit treatments included 85% of irrigation amount (slight water deficit, LD), 70% of irrigation amount (moderate water deficit, MD<inf>1</inf>), 55% of irrigation amount (mild water deficit, MD<inf>2</inf>), and 40% of irrigation amount (severe water deficit, SD)). The response of photosynthetic characteristics of citrus leaf to water deficit were observed by measuring variation of transpiration rate, photosynthetic rate, stomatal conductance, intercellular CO2 concentration, stomatal limits, non-stomatal limits and instaneous leaf water use efficiency. The fruit yield and water use efficiency based on irrigation and evapotranspiration were also determined. The results showed that the photosynthetic rate varied in a dual-peak curve during the day. The photosynthetic rate of mild and severe deficit was significantly lower than the CK but that of slight deficit treatment was not significantly different from the CK. The transpiration rate was increased then decreased during the day for all the treatments and it was only significantly lower for the severe and relative mild deficit treatments compared to CK. The intercellular CO<inf>2</inf>concentration was not significantly different for the LD and CK treatments. The carboxylation rate was also similar for the LD and CK. The instaneous leaf water use efficiency of IV-LD was significantly higher than the CK and increased by 36.61% (P<0.05). With decreasing the irrigation amount the stomatal limits increased by 1.24%-20.11% and the non-stomatal limits increased by 2.17%-33.99%. When the treatment changed from MD<inf>2</inf>to SD and from MD<inf>1</inf>to MD<inf>2</inf>, the influential factor of citrus photosynthesis changed from stomatal factors to non-stomatal factors. The evapotranspiration decreased with increasing degree of water deficit. The evapotranspiration of water deficit treatments at fruit expansion stage and at fruit maturity stage decreased by 10.7%-36.3% and 6.7%-12.2%, respectively. The yield of LD treatments was not significantly from that of CK. However, compared to CK, the water use efficiency based on evapotranspiration of III-LD and IV-LD treatments was increased by 13% and 9.5%, respectively; the water use efficiency based on irrigation amount of III-LD and IV-LD treatments was increased by 11% and 6.87%, respectively. Thus, the slight water deficit could not only keep fruit yield but also increase water use efficiency, which was a suitable water deficit model for citrus. The study provides valuable information for understanding citrus tree growth in drought stress.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Plants (botany)
Controlled terms:Carbon dioxide - Carboxylation - Citrus fruits - Drought - Efficiency - Evapotranspiration - Forestry - Irrigation - Photosynthesis - Transpiration - Water supply
Uncontrolled terms:Citrus - Drip irrigation - Leaf - Stomatal limitations - Water deficits - Water use efficiency
Classification code:444 Water Resources - 446.1 Water Supply Systems - 461.9 Biology - 802.2 Chemical Reactions - 804.2 Inorganic Compounds - 821.3 Agricultural Methods - 821.4 Agricultural Products - 913.1 Production Engineering
Numerical data indexing:Age 7.00e+00yr, Percentage 1.00e+02%, Percentage 1.07e+01% to 3.63e+01%, Percentage 1.10e+01%, Percentage 1.24e+00% to 2.01e+01%, Percentage 1.30e+01%, Percentage 2.17e+00% to 3.40e+01%, Percentage 4.00e+01%, Percentage 5.50e+01%, Percentage 6.70e+00% to 1.22e+01%, Percentage 6.87e+00%, Percentage 7.00e+01%, Percentage 8.50e+01%, Percentage 9.50e+00%, Size 1.00e-01m, Size 2.80e+00m to 3.00e+00m
DOI:10.11975/j.issn.1002-6819.2018.03.019
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 24>
Accession number:20181605031859
Title:Design and experiment of sliding-cutting and anti-twining returning device for banana straw
Authors:Zhang, Xirui (1); Wang, Ziqiang (1); Li, Yue (1); Liang, Dong (1)
Author affiliation:(1) School of Mechanics and Electrics Engineering, Hainan University, Haikou; 570228, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:26-34
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The banana stalks are rich in fiber, and the existing returning machines for banana straw and stubble crushed in China have generated a few problems such as overly severe cutting resistance, the fiber of banana straw winding crushing blade roller on the returning machine, working on the unstable condition and serious fuel consumption. In order to deal with the above problems which the existing choppers met with in the working process, with the help of theoretical study and the analysis on the planting model for banana in Hainan Province, this paper put forward a returning method that the moving knives on the front knife roller were used to crush banana straws and the flail knives on the back knife roller were used to break stubble under the earth. The rotational direction of stubble crushing roller in the returning machine was same to the forward direction of the machine providing power, while the rotational direction of straw crushing roller was contrary to that of stubble crushing roller. On the basis of establishing theoretical model and the analysis on the planting model for banana in southern China, the key shaped parameters of the sliding-cutting blade and the structural parameters of crushing blade rollers were determined respectively. Besides, the sliding-cutting and anti-twining returning device for banana straw was put forward. The overall structure and working principle of sliding-cutting and anti-twining returning device were described. The performance of crushing banana straw and the power consumption were evaluated by simulating the breaking operation of banana straw in farmland through a bench test driven by double electric motors. The machine was composed of electrical motors, a tractor powered by electricity, the frame of machines, the straw crushing device and the stubble crushing device. Through Design-Expert software, a quadratic orthogonal rotating experiment was performed. Based on the variance analysis and regression fitting, a multiple regression equation was gained, presenting the effects of the working speed of the returning device, the rotating speed of rotating roller of moving knives and the rotating speed of rotating shaft of stubble breaking on the qualified rate of straw crushing and power consumption. It could be seen that the rotating speed of rotating roller of moving knives had the most influential effect, followed by the rotating speed of rotating shaft of stubble breaking, and the working speed of the returning device had the least influence on the qualified rate of straw chopping. The operation condition was optimized by applying the response surface method. The optimum factors for straw and stubble crushing process were as follows: The rotating speed of rotating roller of moving knives was 1 600 r/min, the rotating speed of rotating shaft of stubble breaking was 500 r/min, and the working speed of the returning device was 1.39 m/s. Based on the theoretical analysis, the higher qualified rate of straw crushing was achieved under the faster rotating speed of rotating roller of moving knives. The smaller power consummation was obtained under the lower rotating speed of rotating roller of moving knives and the lower rotating speed of rotating shaft of stubble breaking. Under the optimal condition, the corresponding qualified rate of straw crushing and power consumption were 95.2%, and 4.96 kW, respectively. The differences between the experimental and the analytical values of the qualified rate of straw chopping and power consumption were 0.31 percentage points and 0.27%, respectively, which indicated that the software analytical value was in great agreement with the experimental value. And by field test, qualified rate of straw crushing of machine proposed in this paper was higher by 1.94 percentage points and power consumption was lower by 11.3%, compared with vertical flail banana stalk crushing machine. Its successful implementation can greatly improve the production efficiency for crushing banana straw and stubble on one hand, and on the other hand prevent the pollution brought by deserted banana straw putridity.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Crushing
Controlled terms:Agricultural machinery - Choppers (circuits) - Design - Electric power utilization - Fruits - Machine design - Machine windings - Rollers (machine components) - Rotating machinery - Speed - Straw - Testing
Uncontrolled terms:Anti-twining - Cutting blades - Multiple regression equations - Operation conditions - Production efficiency - Response surface method - Rotational directions - Structural parameter
Classification code:601 Mechanical Design - 706.1 Electric Power Systems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
Numerical data indexing:Percentage 1.13e+01%, Percentage 2.70e-01%, Percentage 9.52e+01%, Power 4.96e+03W, Rotational_Speed 1.60e+03RPM, Rotational_Speed 5.00e+02RPM, Velocity 1.39e+00m/s
DOI:10.11975/j.issn.1002-6819.2018.03.004
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 25>
Accession number:20181605031861
Title:Design of poultry eviscerated manipulator and its control system based on tactile perception
Authors:Xiong, Lirong (1); Zheng, Wei (1); Luo, Shuhao (1)
Author affiliation:(1) College of Engineering, Huazhong Agricultural University, Wuhan; 430070, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:42-48
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Aiming at the problem of poultry entrails easy to be damaged in the poultry eviscerated processing, we designed the manipulator and its control system based on tactile perception in this paper. According to the size and depth of abdominal part of broiler with the general size, the maximum distance from the mechanical gripper when it is opened and the length range of the mechanical finger are respectively determined. Through the analysis of the poultry entrails, the bending degree of the mechanical fingers is determined, and then the envelope space when the mechanical gripper is closed is determined. The three-dimensional model of the mechanical gripper is established by SolidWorks software. The size of mechanical gripper is determined by the movement analysis and the assembly of mechanical gripper. The mechanical gripper is driven by a screw, the rotary motion of the stepper motor is converted into a linear motion of the slider by means of a screw, and then through the connecting rod the movement of mechanical fingers is achieved. STM32 single chip microcomputer is used to generate PWM (pulse width modulation) signal to control the move of mechanical arm in X, Y, Z axis direction, and at the same time to control the positive direction rotation of stepping motor of manipulator, achieving the closing of mechanical paw. The piezoresistive film sensor is used as the tactile sensing part of the mechanical gripper. When the pressure on the sensor becomes larger, the resistance value becomes smaller. On the other hand, when the pressure becomes smaller, the resistance value becomes larger. Single chip microcomputer can collect the voltage signal, but can not directly collect the resistance signal, so the resistance-voltage conversion module is used to make the changes of resistance value of the sensor that is caused by the changeable pressure on the sensor, which becomes the corresponding voltage signal. In this way, the ADC (analog-to-digital converter) module of single chip microcomputer is used to collected the pressure of piezoresistive type film sensor in real time installed in the inside of finger. We make the 4 broilers as a group and conduct the visceral pressure threshold test of broiler with a total of 3 groups of broilers and the pressure threshold of the mechanical gripper is determined. We compare the collected pressure with pressure threshold value that is 7.7 N, and control reverse rotation of stepping motor of manipulator, so as to control the force of manipulator paw to ensure that entrails would not endure too much force to be damaged, or would not fall off due to closing not enough. Qt Creator is used to draw the user graphical interface of poultry eviscerated manipulator, and the interface is mainly composed of serial port, display box, automatic mode, manual mode and operation control, and includes manual and automatic control modes. In automatic mode, you can enter the running distance of the 3 axes to determine the movement state of the manipulator, and at the same time, in manual mode, you can click the manual button to control the action of the robot. The PC (personal computer) and STM32 single chip microcomputer are connected by the serial data cable, and then the system is initialized. In this way, you can operate the control interface. In addition, when the manipulator gets trouble in the working process, you can click the stop button to make all the stepper motors disabled, to ensure the safety of equipment. The results of test showed that mechanical paw with the tactile system could significantly reduce the damage of entrails, the average score of visceral damage decreased from 4.75 to 4, and the evisceration rate was 87.4%. The manipulator has the advantages of stable performance, less damage to entrails, high degree of automation, friendly human-computer interface and easy control, and has high practical value.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Manipulators
Controlled terms:Analog to digital conversion - Automation - Computer control - Computer control systems - Control engineering - Grippers - Haptic interfaces - Human computer interaction - Personal computers - Pulse width modulation - Screws - Sensors - Stepping motors - Testing - Voltage control - Voltage measurement
Uncontrolled terms:ADC(analog-to-digital converter) - Degree of automation - Haptic systems - Human computer interaction interface - Human computer interfaces - Single chip microcomputers - Solidworks software - Three-dimensional model
Classification code:605 Small Tools and Hardware - 705.3 Electric Motors - 722.2 Computer Peripheral Equipment - 722.4 Digital Computers and Systems - 731 Automatic Control Principles and Applications - 942.2 Electric Variables Measurements
Numerical data indexing:Percentage 8.74e+01%, Force 7.70e+00N
DOI:10.11975/j.issn.1002-6819.2018.03.006
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 26>
Accession number:20181605031866
Title:Gear preselector characteristics and control strategy of dual clutch transmission
Authors:Liu, Xi (1); He, Ren (1); Cheng, Xiusheng (2)
Author affiliation:(1) College of Automotive & Traffic Engineering, Jiangsu University, Zhenjiang; 212013, China; (2) College of Automotive Engineering, Jilin University, Changchun; 130025, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:80-87
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Gear preselector is a key component for gear shifting of dual clutch transmission (DCT) and a premise for clutch interaction. To realize quick and comfortable shifting, the control of gear preselector must be immediate and steady. As the odd and even gear of DCT belong to different clutches, this paper firstly analyzed the principle and power transmission line of gear preselector and then formulated gear preselection strategy that could take full use of its structural advantage. Through pressure control of target gear under special operating condition, the speed regulation of gear shaft in to-be-connected gear ring was realized, and thus the speed difference between master and slave part of synchronizer was reduced as much as possible, and smaller degree of sliding friction and shorter synchronization time during synchronizing process could be achieved. Subsequently, from the perspective of kinematics and dynamics and based on the mechanical structure of gear preselector, the neutral gear self-lock resistance, frictional force, synchronizing force of joint sleeve, resistance force of joint ring gear, and shifting fork self-lock force were investigated. Through calculating the resistance forces related with fork position during different stages, the relation between synchronizing force and synchronization time could be revealed, and the resistance model of preselection process could be established. After that, by selecting degree of shock and slipping friction work as 2 evaluation indices for gear preselector, the relationships between degree of shock and shifting force during synchronizing process and during joint sleeve-joint gear ring engagement process were analyzed, as well as the relationship between slipping friction work and shifting force during synchronizing process. On the basis of guaranteeing the smoothness of preselection process and under the premise that the synchronizing ring would not be worn, allowable values of degree of shock and extreme sliding power were set. Based on these 2 extreme values and combined with gear shifting resistance, shifting forces during various stages of preselection process were determined. Then, the preselection process was divided into different stages according to preselection theory and characteristics. The time length of each stage of preselection process was determined using empirical data based on the relation between synchronizing force and synchronization time. The target position of shifting fork at any time during engaging and disengaging gear process was set using structural parameters of shifting fork and synchronizer. On this basis, the closed-loop fuzzy control strategy for fork position was proposed. That was, the target position of shifting fork was firstly determined according to preselection process time-series, and then target position and actual position of shifting fork were compared to obtain the position difference and position difference change rate, which would be used as inputs of fuzzy controller. Shift force adjustment was generated through fuzzy rule, which was then combined with shifting resistance force at actual position. The combination force was be used as output of target shifting force, which was applied on shifting fork and to realize preselection process. In this process, the fuzzy controller adopted a triangle uniform distribution function as membership function, Mamdani algorithm was adopted as inferential principle, and centroid method was employed against blurring. Finally, gear preselection test was conducted on a smooth road surface based on a certain test vehicle with 6DCT, wherein the process of engaging a gear when vehicle decreased from second gear to first gear was selected as gear engagement condition, while the process of disengaging a gear after vehicle increased from first gear into second gear was selected as out-of-gear condition. In this test, the comparative analyses were conducted between target displacement and actual displacement of shifting fork, between shifting force and resistance force, between gear ring rotation speed and joint sleeve rotation speed, and between actual degree of shock and allowed value of degree of shock. The analyses results showed that the resistance model of gear preselector could well simulate the resistance characteristics during preselection process of DCT, the proposed preselection control strategy (including coordination control strategy for reducing master-slave rotation speed difference and tracking control strategy for shifting fork target position) could realize accurate tracking of target position of shifting fork with the maximum tracking error no more than 4.67%, and the preselection process was quick and smooth, which could meet the requirement of gear preselector quality. This study provides reference for the research of DCT preselection characteristics and control.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Process control
Controlled terms:Closed loop control systems - Clutches - Control engineering - Controllers - Distribution functions - Friction - Fuzzy control - Fuzzy inference - Gears - Locks (fasteners) - Membership functions - Speed - Synchronization - Transmissions - Tribology - Vehicle transmissions - Vehicles
Uncontrolled terms:Closed loops - Dual clutch transmission - Dual clutch transmission(DCT) - Fuzzy control strategy - Kinematics and dynamics - Pre-selection - Resistance characteristics - Synchronizer
Classification code:601.2 Machine Components - 602.2 Mechanical Transmissions - 721.1 Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory - 731 Automatic Control Principles and Applications - 732.1 Control Equipment - 921 Mathematics - 922.1 Probability Theory - 931 Classical Physics; Quantum Theory; Relativity - 961 Systems Science
Numerical data indexing:Percentage 4.67e+00%
DOI:10.11975/j.issn.1002-6819.2018.03.011
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 27>
Accession number:20181605031863
Title:Analysis of pelleting movement characteristics of BYW-400 type vibrating seed coating machine for wheatgrass
Authors:Shao, Zhiwei (1); Chen, Zhi (1); Hou, Zhanfeng (1); Mi, Longkai (1); Qiu, Yi (1)
Author affiliation:(1) College of Mechanical and Electrical Engineering, Inner Mongolia Agricultural University, Hohhot; 010018, China
Corresponding author:Chen, Zhi(sgchenzhi@imau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:57-64
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Seed pelleting coating is an important step in the pretreatment of forage seeds, and understanding the dynamic process of pelleting can better set up coating parameters and improve the qualified rate of pelleting. In order to understand the characteristics of pelleting movement of pelleted seed coating machine, the dynamic movement law of pellets needs to be studied accurately. The theoretical analysis, simulation and experimental verification of the BYW-400 type vibrating pelleting machine for wheatgrass seeds were studied. Based on Hertz contact theory, the vibration model and rotation model of single particle impact workpiece surface were established for vibration coating of pill coating machine. Meanwhile, the flow characteristics of material flow were analyzed. The results of theoretical analysis showed that the pelleting of wheatgrass seeds was related to the collision depth, maximum load, roughness of material flow and the thickness of cohesive bottom. The introduction of vibration can change the speed and increase the inertia force. Thus, the collision depth and maximum load of seed and powder were affected, the roughness height was increased. Besides, the turbulent flow property was enhanced, and the movement complexity between particles was increased. At the same time, the mixing degree between seed powder was improved, and the qualified rate of seed pelleting was finally improved. The same solution can be achieved when the pot body angle should not be smaller than the natural feet of the material, otherwise the material would stick on the pan surface, and lost the role of rolling together with its rotation. So it was necessary for us to choose the right size of the dip angle. The analysis of material flow characteristics showed that the introduction of vibration can increase the inertia force and increase the Reynolds number, which can improve the turbulent flow property, increase the irregular movement degree between particles, and improve the qualified rate of seed pelleting. In addition, EDEM software was used to simulate the simulation which the vibration intensity was 21% and no vibration and different tilt angles were simulated by 10 s, respectively. At the same time, the trajectory curve was plotted. The simulation results were analyzed by mixing degree, and the broken line diagram was obtained. Besides, the specific data was used to reflect the quality of mixed pelleting. The simulation results were consistent with the theoretical analysis, and the effect of vibration and inclination angle on the results of coating pelleting was verified. In addition, the effect of vibration and rotation angle was determined by coating single factor contrast experiment. Single factor experiments with six different factors were carried out, and the average value of each group was calculated many times. The qualified rate(the percentage of the coated area more than 80% particles accounting for the total number of samples and the weight is 7~10 times that of the original), seed rate (the percentage of the pelleted seed to account for the percentage of the total) and single seed rate(the percentage of the pelleted seed only 1 grains account for the total number of the samples) of pelleted seeds were calculated as the evaluation index of coating quality. When the speed of coating machine was 48.6 r/min., the dip angle of coating pot was 40.3° and the vibration intensity was 21%, the qualified rate of pelleting was 89.5%. Therefore, the change of vibration intensity can obviously affect the rate of pelleting. When the tilt angle of the coating pot was about 45°, the qualified rate of pelleting reached 89.7%. Thus, the dip angle of the coating pot was 45°, which was an ideal coating state. The results provide reference for the coating of irregular seeds.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Vibration analysis
Controlled terms:Acoustic wave absorption - Coatings - Computer software - Mixing - Models - Pelletizing - Quality control - Reynolds equation - Reynolds number - Rotation - Seed - Turbulent flow
Uncontrolled terms:Coating machines - Flow charac-teristics - Hertz contact theory - Movement characteristics - Simulation and experimental verifications - Single particle impact - Single-factor experiments - Wheatgrass
Classification code:631.1 Fluid Flow, General - 723 Computer Software, Data Handling and Applications - 751.1 Acoustic Waves - 802.3 Chemical Operations - 813.2 Coating Materials - 821.4 Agricultural Products - 913.3 Quality Assurance and Control - 931.1 Mechanics
Numerical data indexing:Percentage 2.10e+01%, Percentage 8.00e+01%, Percentage 8.95e+01%, Percentage 8.97e+01%, Rotational_Speed 4.86e+01RPM
DOI:10.11975/j.issn.1002-6819.2018.03.008
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 28>
Accession number:20181605031880
Title:Inversion model of pasture crude protein content based on hyperspectral image
Authors:Zhang, Aiwu (1, 2); Yan, Wenyan (1, 2); Guo, Chaofan (1, 2)
Author affiliation:(1) Key Laboratory of 3D Information Acquisition and Application, Ministry of Education, Capital Normal University, Beijing; 100048, China; (2) Engineering Research Center of Spatial Information Technology, Ministry of Education, Capital Normal University, Beijing; 100048, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:188-194
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Crude protein (CP) is the key indicator for evaluation of the quality and feeding value of pasture grass. Timely, accurate and non-destructive assessment of pasture grass CP content is important for pasture grass growth monitoring and making-decisions for adjusting stocking rate and pasture management, eventually preventing grassland degradation. Hyperspectral remote sensing technology provides the potential for monitoring the nutrition in large areas of grassland. In order to obtain the distribution of pasture grass CP content in Jinyintan Grassland, which is a typical prairie in Haiyan County, Qinghai Province, a new type of hyperspectral imaging system based on high altitude airship (named ASQ-HAA380) was used to collect the high-resolution hyperspectral images, and the ground-based pasture grass CP samples datasets were collected at the same time and analyzed in Qinghai University. The aim of this study was to establish the regression model and seek the optimal model to estimate CP content and draw its distribution map. This study analyzed the possibility using several spectral variables and different modeling methods. On the basis of a comprehensive analysis of the hyperspectral data, the best spectral indices i.e. simple ratio spectral index (SR) and normalized difference spectral index (ND) were taken as independent variables to build univariate models. Besides, the multivariate stepwise linear regression method and multivariate nonlinear regression method were used to build estimate models of other spectral variables, including original reflectance spectrum (R), first derivative of reflectance (D(R)), logarithm transformation of reflectance (log(R)), normalized transformation of reflectance (N(R)), first derivative of log(R) (D(log(R))), logarithm transformation of N(R) (log(N(R))), first derivative of N(R) (D(N(R))), band depth (BD), and continuum removed derivative reflectance (CRDR). Afterwards, the accuracies of these models were evaluated through cross-validated coefficient of determination (R<sup>2</sup>) and cross-validated root mean square error (RMSE). The results showed: 1) Derivative spectral variables could effectively estimate CP content with high stable ability among all spectral variables, and R<sup>2</sup>is more than 0.794. 2) Compared with these multiple regression models, the nonlinear regression model had higher precision than the corresponding linear regression model. 3) The accuracy of the multiple nonlinear regression model of D(log (R)) built in the study was the highest, R<sup>2</sup>was 0.918 and RMSE was 0.054, and the model of D(log(R)) was the optimal model for prediction of CP content. The inversion nonlinear regression model of D(log(R)) was applied to the hyperspectral image to obtain the spatial distribution of CP content in the study area. The research provides reference and technical basis for the quantitative inversion of CP content in large area scales and the efficient implementation of precision livestock husbandry based on hyperspectral images, and also lays the foundation for the development of wisdom livestock husbandry in the future.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Agriculture
Controlled terms:Decision making - Hyperspectral imaging - Image resolution - Independent component analysis - Linear regression - Linear transformations - Mathematical transformations - Mean square error - Model buildings - Optical waveguides - Proteins - Quality control - Reflection - Remote sensing - Spectroscopy - Vegetation
Uncontrolled terms:Coefficient of determination - Crude proteins - Hyperspectral remote sensing technology - Multiple nonlinear regression - Multivariate non-linear regression - Nonlinear regression models - Spectral indices - Vertification
Classification code:714.3 Waveguides - 804.1 Organic Compounds - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 912.2 Management - 913.3 Quality Assurance and Control - 921.3 Mathematical Transformations - 922.2 Mathematical Statistics
DOI:10.11975/j.issn.1002-6819.2018.03.025
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 29>
Accession number:20181605031876
Title:Biochar and nitrogen amendments improving soil aggregate structure and jujube yields
Authors:Yuan, Jingjing (1, 2); Tong, Yan'an (1, 2); Lu, Shaohui (3); Yuan, Guojun (3)
Author affiliation:(1) College of Natural Resources and Environment, Northwest A&F University, Yangling; 712100, China; (2) Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling; 712100, China; (3) Academy of Forestry Sciences of Henan Province, Zhengzhou; 450003, China
Corresponding author:Tong, Yan'an(tongyanan135@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:159-165
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Soil aggregate as the fundamental unit of soil structure, is a product of interactions between soil microbial communities and mineral-organic compositions. High and sustainable soil aggregate stability is an important characteristic for preserving soil productivity and restraining soil erosion and degradation. However, there are few literatures about how biochar amendments affect soil aggregate in fruit orchards in China. The objective of this study was to evaluate the effects of combined application of peanut shell biochar and nitrogen (N) fertilizer on the distribution and stability of soil mechanical and water-stable aggregates, and jujube yields based on a three-year consecutive field experiment on fluvo-aquic soils in the North China Plain. This study could elucidate the responses of soil and jujube to soil fertility quality under biochar and N fertilizer application, which can provide a scientific basis for improving soil structure and high-efficient fertilization in jujube plantations. This experiment included 13 treatments: CK (no fertilizer), 4 levels of biochar amendments (C<inf>0</inf>-C<inf>3</inf>: 0, 2.5, 5 and 10 t/hm<sup>2</sup>) and 3 levels of N fertilizer application (N<inf>1</inf>-N<inf>3</inf>: 300, 450 and 600 kg/hm<sup>2</sup>). All samples were separated into 5 aggregate-size classes (>5, 2-5, 1-2, 0.25-1 and >0.25 mm) by dry and wet sieving. The results showed that compared with the control, biochar and N fertilizer amendments had no significant influence on mean weight diameter (MWD), geometric mean diameter (GMD) and the proportions of >0.25 mm macro-aggregates under dry sieving, while the proportions of >0.25 mm water-stable macro-aggregates increased with the biochar, and the highest proportion of this size was observed in the C<inf>3</inf>N<inf>2</inf>treatment with the increment of 20.7%. The values of MWD and GMD under wet sieving were significantly increased by 29.2% and 27.2%, respectively. In addition, the percentage of aggregate destruction was significantly decreased by 27.1%. The contents of oil organic carbon were higher in biochar-amended treatments than in the control, and significant differences were observed for the higher application rates. A significant positive correlation was observed among soil organic carbon content, MWD and GMD (P<0.05) according to the correlation analysis. One year after the application of biochar to the jujube orchard, soil fertility under biochar and N fertilizer amendments increased with the increase of keeping years, and the yields of jujube were also gradually improved. Taking into account the above-mentioned results, we can draw the conclusion that biochar amendment combined with N fertilizer application significantly improved the content of soil water-stable aggregates and aggregate stability, which was conducive to ameliorate soil degradation, and improve jujube yield. The optimal amounts for biochar and N fertilizer according to the comprehensive results should be 10 t/hm<sup>2</sup>and 300 kg/hm<sup>2</sup>, respectively.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:38
Main heading:Soil surveys
Controlled terms:Aggregates - Fertilizers - Nitrogen fertilizers - Orchards - Organic carbon - Soil moisture - Soils - Well drilling
Uncontrolled terms:Bio chars - Mean weight diameter - Stable aggregates - Water stable aggregates - Yields
Classification code:406 Highway Engineering - 483.1 Soils and Soil Mechanics - 804 Chemical Products Generally - 804.1 Organic Compounds - 821.3 Agricultural Methods
Numerical data indexing:Percentage 2.07e+01%, Percentage 2.71e+01%, Percentage 2.72e+01%, Percentage 2.92e+01%
DOI:10.11975/j.issn.1002-6819.2018.03.021
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 30>
Accession number:20181605031858
Title:Experiment on transplanting performance of automatic vegetable pot seedling transplanter for dry land
Authors:Wang, Yongwei (1); He, Zhuoliang (1); Wang, Jun (1); Wu, Chuanyu (2); Yu, Gaohong (2); Tang, Yanhai (1)
Author affiliation:(1) School of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou; 310058, China; (2) College of Machinery and Automation, Zhejiang Sci-Tech University, Hangzhou; 310018, China
Corresponding author:Wang, Jun(jwang@zju.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:19-25
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:To improve the efficiency of mechanization in transplanting vegetable seedlings and achieve the automation of vegetable transplanter in dry land, an automatic vegetable pot seedling transplanter for dry land was developed. This transplanter is mainly composed of 2 rotating seedling picking-up mechanisms of planetary gear train with ellipse gears and incomplete non-circular gears, a horizontal and longitudinal intermittent seedling sending device, 2 eccentric disc dibble-type planting apparatuses, and a power transmission system. Two rotating seedling picking-up devices and 2 eccentric disc dibble-type planting apparatuses were symmetrically arranged along the longitudinal surface center of the machine, constituting 2 sets of automatic seedling picking-up and planting systems. The seedlings were provided automatically from 2 standard seedling pots with 128 holes using the horizontal and longitudinal intermittent seedling sending device. The engine drive shaft could transfer power to the principal axis of the apparatus through chain drive to enable the rotating and planting of the apparatus. Meanwhile, the principal axis of the apparatus could transfer the power to the rotating seedling picking-up mechanisms of planetary gear train with ellipse gears and incomplete non-circular gear and intermittent seedling sending device. Subsequently the intermittent seedling sending device could move horizontally and longitudinally to send the seedling pots to the target place, where the seedling picking-up mechanism took the seedlings from the pot to the eccentric disc dibble-type planting apparatus. To test the performance of this automatic vegetable pot seedling transplanter for dry land, the experiments were conducted in the test field where the soil condition met the mechanical industry standard in People's Republic of China Dry Land Planting Machinery (JB/T 10291-2013). The tomato seedlings (ZheZa 809) used in this experiment were cultivated in the standard seedling pots with 128 holes and transplanted at the age of 35 days with an average height of 150 mm. The seedling sending, picking-up, delivering and planting were all carried out at a constant transplanting frequency by adjusting the speed of the input belt pulley of the walking gear-box. The seedling transplanting efficiency was tested at the low speeds of 45, 60, 75 and 84 plants/min, respectively, as well as at the high speed of 96 plants /min. The coefficient of variation for planting spacing, missing transplanting rate, qualified rate of planting depth and qualified rate of transplanting were determined according to the mechanical industry standard Dry Land Planting Machinery (JB/T10291-2013). The seedling-standing ratio was calculated based on the Technical Specifications of Quality Evaluation for Rape Transplanter (NY/T 1924-2010) according to the standards for agriculture industry in People's Republic of China. The results showed that the coefficient of variation for planting spacing and the missing transplanting rate increased slightly at the range of 6.6%-8.9% and 1.7%-2.8% accordingly when increasing the planting frequency from 45 to 96 plants/min. However, the qualified rate of planting depth, the qualified rate of planting perpendicularity and the qualified rate of transplanting decreased slightly in the range of 97.5%-98.9%, 96.7%-97.8%, and 91.1%-94.7% with the increasing of planting frequency. The coefficient of variation for planting spacing, the missing transplanting rate, the qualified rate of planting depth and the qualified rate of planting all met the requirements of the machinery industry standards (JB/T 10291-2013), and the qualified rate of planting perpendicularity was also within the specified value in the standards for agriculture industry (NY/T 1924-2010). The automatic seedling-sending device, the seedling picking-up device and the planting apparatus of the automatic transplanter coordinated well with each other to complete the process for sending seedlings, picking up seedlings, delivering seedling, planting and soil covering automatically.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Seed
Controlled terms:Agricultural machinery - Automation - Efficiency - Electric power transmission - Epicyclic gears - Mechanisms - Transplants - Vegetables
Uncontrolled terms:Coefficient of variation - People's Republic of China - Performance - Pot seedling - Pot seedling transplanters - Power transmission systems - Seedling transplanting - Technical specifications
Classification code:462.4 Prosthetics - 601.2 Machine Components - 601.3 Mechanisms - 706.1.1 Electric Power Transmission - 731 Automatic Control Principles and Applications - 821.1 Agricultural Machinery and Equipment - 821.4 Agricultural Products - 913.1 Production Engineering
Numerical data indexing:Age 9.59e-02yr, Percentage 1.70e+00% to 2.80e+00%, Percentage 6.60e+00% to 8.90e+00%, Percentage 9.11e+01% to 9.47e+01%, Percentage 9.75e+01% to 9.89e+01%, Size 1.50e-01m
DOI:10.11975/j.issn.1002-6819.2018.03.003
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 31>
Accession number:20181605031892
Title:Gelatin coating treatments to maintain freshness of porcine m. longissimus dorsi muscle during cold storage
Authors:Wang, Wei (1); Liang, Lijiao (1); Shen, Juan (1); Ge, Yiqiang (2); Tang, Xiaoyan (3); Zhou, Guanghong (1)
Author affiliation:(1) National Center of Meat Quality and Safety Control, College of Food Science and Technology, Nanjing Agricultural University, Nanjing; 210095, China; (2) China Rural Technology Development Center, Beijing; 100045, China; (3) Institute of Quality Standard and Testing Technology for Agro-products, Chinese Academy of Agricultural Sciences, Beijing; 100081, China
Corresponding author:Zhou, Guanghong(ghzhou@njau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:279-284
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:As consumers are mainly concerned about meat odor and color, chilled meat has a higher possibility of rejection due to their perishability. In order to solve the above problems, antioxidants and packaging technologies have been widely applied into the meat industry, but considering risks due to the consumption of antioxidants, low convenience and cost effectiveness of packaging solutions, there is an urgent need for an alternative technology that decreases risk, offers convenience and minimizes the price of processing. Edible coatings have been used to preserve meat quality, but their application is limited in the meat industry. The potential of gelatin as an edible coating comes from its film forming capability. Currently, gelatin has been used as a kind of coating material for food products and in certain instances has been a practical and successful protecting agent. The purpose of this research was to study the effect of gelatin coating on maintaining oxidative stability and freshness of chilled pork with a storage period of 7 d. Porcine m. longissimus dorsi muscles were selected from 10 carcasses cooled for 24 h at 4℃, from a local abattoir. Samples were cut into rectangular shape (10 cm × 5 cm × 2 cm) regardless of the fiber direction, and divided into 3 groups, weighed and refrigerated (4℃) until treated. The meat samples were coated with pork skin gelatin (expansion coefficient of 175 bloom) at 3 concentrations (0, 10%, and 20%) for 5 s at 60℃. The control samples were not dipped. After treatment all samples were reweighed. All samples were stored at 4℃ for 7 d with no packaging as a means to prevent the change of meat quality in a simulated fresh retail display setting, and pressing water loss rate, thiobarbituric acid reactive substances (TBARS), heme iron (HI) mass fraction, protein carbonyl, TVB-N (total volatile basic nitrogen) value, color change, and metmyoglobin (MetMb) mass fraction were analyzed. The results indicated that there was a significant difference (P<0.05) for TBARS values, HI mass fraction, protein carbonyl, a* value, MetMb mass fraction with treatments maintaining the values more similar to a fresher product compared to the controls on the 3rd, 5th and 7th day. In addition, there was no significant difference (P>0.05) on any of the parameters between 10% and 20% gelatin coating in storage days. Our experiments confirmed that the application of gelatin coating to pork helped to extend the shelf life of pork when stored at 4℃. Gelatin coating helped to reduce total color change, prevent a loss of redness and retard MetMb formation, thus preserving the appearance of meat. Gelatin coating also slowed down lipid oxidation, protein oxidation and decomposition, and HI conversion, thus reducing the chance of formation of off-flavors in the meat. In addition, gelatin's ability to decrease moisture loss would improve the value of meat. Gelatin coating would be applied on fresh meat during refrigeration storage if the product is to be sold within a couple of days. In conclusion, gelatin coating treatment is an effective alternative technique that should be introduced to the meat industry and the consumer for prolonging the shelf life of the product.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Meats
Controlled terms:Antioxidants - Coatings - Cold storage - Color - Colorimetry - Cost effectiveness - Costs - Food additives - Loss prevention - Muscle - Oxidation - Proteins - Quality control
Uncontrolled terms:Alternative technologies - Expansion coefficients - Freshness - Gelatin - Longissimus dorsi - Packaging technologies - Thiobarbituric acid reactive substances - Total volatile basic nitrogens
Classification code:461.2 Biological Materials and Tissue Engineering - 644.3 Refrigeration Equipment and Components - 741.1 Light/Optics - 802.2 Chemical Reactions - 804.1 Organic Compounds - 813.2 Coating Materials - 822.3 Food Products - 911 Cost and Value Engineering; Industrial Economics - 911.2 Industrial Economics - 913.3 Quality Assurance and Control - 941.4 Optical Variables Measurements
Numerical data indexing:Percentage 1.00e+01%, Percentage 1.00e+01% to 2.00e+01%, Percentage 2.00e+01%, Size 2.00e-02m, Time 5.00e+00s, Time 8.64e+04s
DOI:10.11975/j.issn.1002-6819.2018.03.037
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 32>
Accession number:20181605031871
Title:Effect of irrigation times on nitrogen loss, water and nitrogen use efficiencies in oasis spring maize farmland
Authors:Shi, Xinrui (1); Xu, Qiang (1); Hu, Kelin (1); Li, Sien (2)
Author affiliation:(1) College of Resources and Environmental Sciences, China Agricultural University, Ministry of Agriculture, Beijing; 100193, China; (2) College of Water Conservancy and Civil Engineering, China Agricultural University, Beijing; 100083, China
Corresponding author:Hu, Kelin(hukel@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:118-126
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Exploring the effects of different irrigation times on nitrogen (N) loss, and water and N use efficiencies (WUE, NUE) of spring maize in desert oasis can provide advice for the establishment of rational water and fertilizer management measures in desert oasis. In this study, we investigated the effect of irrigation times on farmland N loss, crop yield and water and nitrogen use efficiency. A field experiment was conducted in the basin of Shiyang river, Gansu province in 2015. The soil was loam with obvious layers. A total of 5 different water and fertilizer combined practices were designed and they included 1 conventional fertilizer and irrigation treatment I<inf>1</inf>N<inf>1</inf>(4 irrigation events) and 4 optimal fertilizer and irrigation treatments: I<inf>2</inf>N<inf>2</inf>(4 events), I<inf>3</inf>N<inf>2</inf>(5 events), I<inf>4</inf>N<inf>2</inf>(6 events) and I<inf>5</inf>N<inf>2</inf>(7 events). The total irrigation amount of conventional and optimal treatments was 480 and 420 mm, respectively. The fertilization rate of the conventional and optimal treatment was 280 and 200 kg/hm<sup>2</sup>, respectively. Each treatment replicated 3 times. The spring maize was planted in April in 2015. A soil Water Heat Carbon and Nitrogen Simulation (WHCNS) model was used to simulate the crop yield, water and N dynamic process, water use efficiency (WUE) and nitrogen use efficiency (NUE) under different treatments. The conventional treatment was used for model calibration and the other 4 treatments were used for model calibration. Then, an integrated index method was employed to obtain the best management practices (BMPs). The results showed that the simulated soil water content, soil NO<inf>3</inf><sup>-</sup>-N content, crop yield and the leaf area index agreed well with the measured values. The root mean square error (RMSE) of soil water content was closer to 0. The RMSE of soil NO<inf>3</inf><sup>-</sup>-N content was 4.32 mg/kg and above and the RMSE of leaf area index was 0.26 m<sup>2</sup>/m<sup>2</sup>and above. The agreement index ranged from 0.74 to 1. The effects of irrigation times on soil moisture and nitrogen leaching were further studied based on the model simulation. The simulation showed that the optimal irrigation times could reduce water drainage. Compared to the conventional treatment, the optimal treatment decreased the drainage from 67 to 24-44 mm. In addition, the increasing the irrigation times could reduce the evaporation and N leaching. Among the 5 treatments, the crop yield, WUE and NUE of I<inf>3</inf>N<inf>2</inf>treatment were the highest, with the values of 17 077 kg/hm<sup>2</sup>, 3.23 kg/m<sup>3</sup>and 40.1 kg/kg, respectively. The amounts of water drainage and N leaching for I<inf>1</inf>N<inf>1</inf>were the highest, while they were the lowest for I<inf>5</inf>N<inf>2</inf>.When the irrigation amount is given, with the increase of irrigation times, the amount of water drainage decreased slowly, the amounts of N leaching and ammonia volatilization decreased gradually, while the amounts of denitrification and crop N uptake gradually increased. The results of integrated index evaluation method indicated that the irrigation 5 times with the total irrigation amount of 420 mm was the BMPs under the specific weather condition in the study areas. We concluded that increasing irrigation frequency and reducing the amount of single irrigation cannot only maintain high crop yield, but also reduce water drainage and N leaching, and meanwhile improve WUE and NUE significantly.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Irrigation
Controlled terms:Crops - Efficiency - Farms - Leaching - Mean square error - Nitrogen fertilizers - Soil moisture
Uncontrolled terms:Ammonia volatilization - Best management practice (BMPs) - Conventional treatments - Farmland - N loss - Nitrogen-use efficiency - Root mean square errors - Spring maize
Classification code:483.1 Soils and Soil Mechanics - 802.3 Chemical Operations - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 913.1 Production Engineering - 922.2 Mathematical Statistics
Numerical data indexing:Mass_Density 3.23e+00kg/m3, Size 2.40e-02m to 4.40e-02m, Size 4.20e-01m, Size 4.80e-01m
DOI:10.11975/j.issn.1002-6819.2018.03.016
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 33>
Accession number:20181605031891
Title:Design of control system for spray chilling operation of pig carcass based on PLC
Authors:Chen, Yulun (1, 2); Sun, Chenyang (1); Lu, Zhongshan (1); Fan, Leiming (1); Li, Yinian (1, 2); Li, Chunbao (2)
Author affiliation:(1) College of Engineering, Nanjing Agricultural University, Nanjing; 210031, China; (2) Key Laboratory of Animal Products Processing of Ministry of Agriculture, Key Laboratory of Meat Processing and Quality Control, Nanjing Agricultural University, Nanjing; 210095, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:273-278
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The temperature of pig carcass rises after slaughtering, so the carcass needs to be cooled immediately to reduce the water loss and improve the quality of meat. Currently, spray chilling is considered as an effective method to reduce the weight loss of pig carcass during the cooling process. Nevertheless, manual operation is generally used for implementing a way of spray chilling in productive process, as a result of lacking the research on the equipment for spray chilling. To solve the problem that manual operation of spray chilling inevitably results in onerous labor and imprecise effect, this study designed a control system of spray chilling, which uses PLC (programmable logic controller) as the processor and touch screen as the HMI (human machine interface), so as to realize the automatic start-stop of the spray chilling operation of pig carcasses, and the system supports manual adjustment of spray parameters on the touch screen. According to the design requirements, the corresponding network program includes the main program, the subroutine of pipe control, the subroutine of interlocking function, the subroutine of pump control, the subroutine of air compressor control, and so on. Among them, the subroutine of pipe control includes opening of gas supply electromagnetic valve, opening of water supply electromagnetic valve and timing of opening interval. The subroutine of interlocking ensures that the remaining pipelines are locked when a pipeline is opened. And the subroutines of the pump and air compressor are used for the supply of water and gas. In this system, the PLC and the expansion module use the relay output signal to control actuating elements including nozzles, solenoid valve, and so on. Additionally, the touch screen is connected with PLC by the MPI/PPI communication cable. Before spraying, operators open the pipeline which is selected to spray, and then the PLC controls the corresponding nozzle, solenoid valve and other components in order to automatically accomplish the entire spray operation on the basis of modulated parameters, which include the total time of spray chilling with high frequency, the interval time of high frequency spray period, the total time of spray chilling with low frequency, the interval time of low frequency spray period and the single spray time. This paper tested the effect of this control system on the weight loss of pig carcass under the conditions that the total time of spray chilling with high frequency was 2 h, the interval time of high frequency spray period was 30 min, the total time of spray chilling with low frequency was 4 h, the interval time of low frequency spray period was 60 min, and the single spray time was 20 s. The results showed that the water loss rate within 24 h measured by the control system was 1.25%±0.07% in summer and 1.19%±0.05% in winter, and that measured by manual operation was 1.59%±0.14% in summer and 1.34%±0.10% in winter. Analysis of variance showed that the stability of water loss rate measured by the system was significantly higher than manual work (P<0.05), and it did not be affected by the seasons (P>0.05). The slaughtering enterprise, in the test, has 8 cold storage tanks, and a spray in one cold storage tank needs 5 min under the manual operation. So it needs at least 2 workers to complete the spray task when the high-frequency spray interval is 30 min. Compared with the manual operation, this system can eliminate heavy labor and save human cost due to its features of operating easily, working stably and reliably. Not only does it provide a reference for the research of automation equipment of spray chilling, it but also can be applied to the field of temperature and weight loss reduction related to pig slaughtering.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Spray nozzles
Controlled terms:Cold storage - Control systems - Controllers - Cooling - Design - Gas compressors - Human computer interaction - Mammals - Pipelines - Programmable logic controllers - Solenoid valves - Solenoids - Spraying - Subroutines - Tanks (containers) - Telecommunication cables - Thermal management (electronics) - Touch screens - Water supply
Uncontrolled terms:Automation equipment - Design of control system - Electromagnetic valves - Human Machine Interface - Modulated parameters - Pig carcass - PLC (programmable logic controller) - Water loss rates
Classification code:446.1 Water Supply Systems - 618.1 Compressors - 619 Pipes, Tanks and Accessories; Plant Engineering Generally - 631.1 Fluid Flow, General - 641.2 Heat Transfer - 644.3 Refrigeration Equipment and Components - 704.1 Electric Components - 722.2 Computer Peripheral Equipment - 723.1 Computer Programming - 731.1 Control Systems - 732.1 Control Equipment
Numerical data indexing:Time 8.64e+04s, Time 1.44e+04s, Time 1.80e+03s, Time 3.00e+02s, Time 3.60e+03s, Time 7.20e+03s
DOI:10.11975/j.issn.1002-6819.2018.03.036
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 34>
Accession number:20181605031869
Title:Constraint of total water consumption amount based on optimized irrigation schedule and planting structure ajustment
Authors:Peng, Zhigong (1, 2); Zhang, Baozhong (1, 2); Liu, Yu (1, 2); Wang, Lei (1, 2); Du, Lijuan (1, 2); Lei, Bo (1, 2)
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; 100038, China; (2) National Center of Efficient Irrigation Engineering and Technology Research-Beijing, Beijing; 100048, China
Corresponding author:Zhang, Baozhong(zhangbz@iwhr.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:103-109
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The aim of this study was to determine the threshold value of the agricultural areas under the dual constraints of the total amount of water intaking and the total amount of water consumption, which is an important value for the healthy development in agriculture of the areas short of water resource similar to the suburbs of Beijing. Firstly, the constraint value of the total amount of agricultural water consumption and the constraint value of the total amount of the water intaking for irrigation in Daxing District, Beijing was analyzed. Then, the changing trends of the agricultural water consumption by adopting the measures such as the optimization of the irrigation schedules and the adjustment of planting structure had been studied. Finally, based on the recommended scenarios of planting structure adjustment, the threshold value for agricultural areas under the constraint of total amount of water consumption was studied. The results showed that: 1) Optimizing the irrigation schedules could significantly reduce the agricultural water consumption and irrigation amount, which enabled the regional water consumption in agriculture to be lower than the constraint value of the total water consumption and enabled the total amount of water intaking for agricultural irrigation to be lower than the actual average level for many years, but the total amount of water intaking for agricultural irrigation was still higher than the constraint value; 2) In Daxing District, the planting areas for the open-field vegetables and winter wheat with higher water consumption were decreased. Then, the planting areas for the summer maize with less irrigation amount and lower water consumption were increased. Meanwhile, the areas for facility agriculture with higher efficiency of agricultural water were developed. Based on these, the constraint values of the total amount of water intaking for agricultural irrigation and the total amount of the water consumption could be met and the requirements to stabilize the grain yields and increase the output of vegetables as prescribed in the Development Planning of Urban Modern Agriculture for the Period of Beijing "12th Five-Year" could be fulfilled; 3) The threshold value to meet the agricultural area under the constraint value of the total amount of water intaking for agricultural irrigation was 4.60×10<sup>4</sup>-7.42×10<sup>4</sup>hm<sup>2</sup>, and that to meet the agricultural areas under the constraint value of the total water consumption was 6.72×10<sup>4</sup>-9.48×10<sup>4</sup>hm<sup>2</sup>. By synergistically using the agricultural water control measures of adjusting the planting structure and optimizing the irrigation schedules, the threshold value was 7.42×10<sup>4</sup>hm<sup>2</sup>; 4) In the case that the total amount of water consumption kept unchanged, with the development of facility agriculture areas, the development areas of traditional agriculture had been reduced, but the areas threshold values of the facility agriculture and traditional agriculture did not align perfectly due to the differences in the constraint values of the total amount of water consumption. In order to maintain the sustainable and efficient utilization of regional water resources, to ensure the healthy development of regional agriculture, it was bound to adopt the water-saving measures such as the optimization of irrigation schedules and the adjustment of planting structure both to control the threshold value for agricultural areas within a reasonable range, so that the total amount of the regional agricultural water consumption would not break through the constraint value of the total amount of water intaking for agricultural irrigation and the constraint value of the total water consumption. The study provides an effective method for regional water amount control in areas short of water resources.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:21
Main heading:Water resources
Controlled terms:Crops - Irrigation - Optimization - Structural optimization - Vegetables - Water conservation
Uncontrolled terms:Agricultural areas - Agricultural irrigation - Development planning - Facility agricultures - Regional water resources - Structure adjustments - Water consumption - Water saving measures
Classification code:444 Water Resources - 821.3 Agricultural Methods - 821.4 Agricultural Products - 921.5 Optimization Techniques
DOI:10.11975/j.issn.1002-6819.2018.03.014
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 35>
Accession number:20181605031887
Title:Spatial and temporal changes and its variation of cultivated land quality in Shaanxi Province
Authors:Wei, Xindong (1); Wang, Shaini (1); Yuan, Xuefeng (1); Wang, Xiaofeng (1); Zhang, Bangbang (2)
Author affiliation:(1) College of Earth Science and Resources, Chang'an University, Xi'an; 710054, China; (2) College of Economics and Management, Northwest A&F University, Yangling; 712100, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:240-248
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The maintenance of high-quality cultivated land is of fundamental and strategic significance to ensure national food security and maintain social stability. To provide a scientific basis for conserving cultivated land resources, basic farmland protection and cultivated land monitoring, taking Shaanxi Province in northwest China as an example, based on the database of cultivated land grade in Shaanxi Province from 2005 to 2015, the spatial and temporal changes of cultivated land quality in Shaanxi Province were analyzed at 3 spatial scales: the provincial level, the geographical area level and the urban level. This research used a combination of methods including spatial analysis, statistical analysis and geo-statistical analysis. Production capacity was the basic measure of cultivated land quality and the land use coefficients reflected the extent to which human production explored the natural potential. The utilization grade, which was calculated from the land use coefficient, reflected the productivity of cultivated land under the average actual inputs and technical conditions in various regions. The data analysis in this paper was based on the utilization grade, which was a closer reflection of the actual level of land output. The results showed: 1) The area of cultivated land in Shaanxi Province decreased by 0.22% in the period from 2005 to 2015. The trend of decline has been stabilized in recent years, which basically reaches the balance of cultivated land. The decline of cultivated land was partly for ecological purposes and partly for construction purposes. The area used for ecological restoration was 77938 hm<sup>2</sup>, from 2005 to 2015. Since 2010, some measures have been implemented to increase the quantity of cultivated land, including preventing the further loss of cultivated land, land reclamation and ecological construction. 2) The average grade of cultivated land quality in Shaanxi Province was 11.33 in 2015, which was not good, and the quality of cultivated land in the province did not change significantly over the past 10 years. The area of excellent-, high-and low-grade land decreased and middle-grade land area increased. The decline in high-grade land area was because urban construction occupied a large amount of high-quality cultivated land. The quality of supplementary cultivated land was low, which resulted in the overall decline of cultivated land quality. Central Shaanxi had a higher quality of cultivated land because it was located on a plain, and the economic, climate and other conditions were relatively good. Therefore, the location quotient of excellent-grade and high-grade land was above the provincial average. The north of Shaanxi had a lower quality of cultivated land because the climate was drier, and the soil was poor. However, the location quotient was stable. 3) Over time the changes in the quality of cultivated land in north Shaanxi, central Shaanxi and south Shaanxi increased, decreased and were stable, respectively. The north of Shaanxi actively carried out land reclamation and ecological civilization construction, resulting in a cultivated land quality grade of 13.35 by the end of the study period. Therefore, both the quantity and the quality of cultivated land in the north of Shaanxi increased. This research provides a scientific basis for the classification and management of cultivated land quality. The area of cultivated land is stable by the end of the study, but the high-grade regions should undertake land consolidation, especially in central Shaanxi.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Land reclamation
Controlled terms:Ecology - Food supply - Land use - Remote sensing - Spatial variables measurement - Statistical methods
Uncontrolled terms:Cultivated land qualities - Cultivated lands - Distribution regulation - Shaanxi Province - Spatial and temporal changes
Classification code:403 Urban and Regional Planning and Development - 442.2 Land Reclamation - 454.3 Ecology and Ecosystems - 822.3 Food Products - 922.2 Mathematical Statistics - 943.2 Mechanical Variables Measurements
Numerical data indexing:Age 1.00e+01yr, Percentage 2.20e-01%
DOI:10.11975/j.issn.1002-6819.2018.03.032
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 36>
Accession number:20181605031860
Title:Optimization design and application of variable rate fertilization system for small-scaled fields
Authors:Yu, Hongfeng (1, 2); Ding, Yongqian (1, 2); Liu, Haitao (1); Zhu, Wenqian (1); Liu, Guoqiang (1); Fu, Xiuqing (1); Ding, Weimin (1, 2)
Author affiliation:(1) College of Engineering, Nanjing Agricultural University, Nanjing; 210031, China; (2) Jiangsu Key Laboratory for Intelligent Agricultural Equipment, Nanjing; 210031, China
Corresponding author:Ding, Yongqian(yingqiand@njau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:35-41
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The farmlands in South Jiangsu province in China usually have characteristics of small acreage with fixed field boundary, balanced fertility inside one field plot and possibly significant fertility difference among different field plots even though some plots are close to each other. The reason for this phenomenon is that farmlands have been already assigned to rural families in small-scale-size plots for decades and the field plots are farmed by rural families independently. Rural families have a good understanding of overall soil fertility and yield potential about their own field plots, but they are not very clear about the matching relationship of target plant production and the needed amount of fertilizer for each field plot. According to the characteristics of farmland plots and the technical barriers of carrying out variable rate fertilization in South Jiangsu province, a simple executable scheme of variable rate fertilization was proposed in this paper. This scheme referred to a rough production-fertilization relation model which was established based on the "target output and fertilizer amount" theory by local government's agricultural departments in South Jiangsu Province. The final scheme for variable rate of fertilizer application is based on yield potential and target production data of the field plots. Using this scheme, the soil fertility of the field plots were classified into different grades. The target production of the field plots were discretized into finite data sets which were corresponding to different target amount of fertilizer application. Implementing this scheme for variable rate of fertilizer application was expected to obtain these effects: uniform application of fertilizer inside one field plot and adjusting the amount of fertilizer application to meet the actual needs of different field plots. The fertilizer-seeder machine for variable rate application, which was equipped with an electronic prescription map system based on the scheme of variable rate fertilization, was renovated from a mechanical sowing machine into an automatically operating system. The renovated system has the ability to automatically sense the working place site and the forward speed in field, and automatically adjusts the flow rate of the seeders with the help from the electronic prescription map system. With single crop field plot which has naturally-formatted boundary as a basic processing unit, the variable rate fertilizer-seeder which was equipped with an electronic prescription map system has the function as following: automatically mixing various fertilizers together as needs, uniform application of fertilizer inside a natural field plot and variable rate fertilization among different natural field plots. In order to further improve the precision quality and working stability. The data from the ordinary precision GPS model were processed with the methods of differential treatment and Kalman-filtering, which can reduce the data fluctuation caused by noise signal. The structure of fertilizer seeder with outer slots was optimized, which can efficiently reduce the edge leakage of fertilizer seeder and improve the flow rate consistency of the fertilizer seeder. Field experiments results showed that the operating outcomes of the electronic prescription map system were correct, the variable rate fertilizer seeder had a stable working state, the biggest and averaged amount errors were correspondingly 3.91% and 2.09%, while the biggest and averaged dynamic errors were correspondingly 4.52% and 1.48%. The research results can be the reference for implementing variable rate fertilization in small-scaled fields in South Jiangsu province in China.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Fertilizers
Controlled terms:Agricultural machinery - Design - Experiments - Farms - Machine design
Uncontrolled terms:Application of fertilizers - Differential treatment - Fertilizer applications - Fields with naturally-formatted board - Optimization design - Variable rate application - Variable rate fertilization - Variable rate fertilizers
Classification code:601 Mechanical Design - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.1 Agricultural Machinery and Equipment - 901.3 Engineering Research
Numerical data indexing:Percentage 1.48e+00%, Percentage 2.09e+00%, Percentage 3.91e+00%, Percentage 4.52e+00%
DOI:10.11975/j.issn.1002-6819.2018.03.005
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 37>
Accession number:20181605031867
Title:Establishment of high precision terrain model of eroded gully with UAV oblique aerial photos and ground control points
Authors:Feng, Lin (1); Li, Binbing (1)
Author affiliation:(1) College of Information Engineering, Engineering University of PAP, Xi'an; 710086, China
Corresponding author:Li, Binbing(libinbing8@vip.sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:88-95
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In this paper, SfM-MVS (structure from motion with multi-view stereo) method was introduced to construct a high precision terrain model of the typical gully on the Losses Plateau of northern Shaanxi in China, with oblique aerial photos acquired by a COTS (commercial off-the-shelf) UAV (unmanned aerial vehicle) (DJI INSPIRE-1) and 30 high-precision pre-deployed ground control points (GCPs) measured by FIFO A30 RTK (real-time kinematic). A sequence of 194 oblique photos were captured by UAV camera with 70° pitch angle following a dual-Z shaped flight route, which were in comparison with 74 orthophotos captured by a nadir-point UAV camera in single Z shaped flight route. The photos were imported into PhotoScan software for terrain construction along with POS (position and orientation) information. Firstly, a preliminary alignment of aerial photos was performed as well as a rough estimation of camera parameters. The RMS (root mean square) reprojection error of tie points was 0.808 pixel and the maximum reprojection error was 41.143 5 pixel. Secondly, the corresponding projections of GCPs were marked on each photo and a set of GCP references were established in PhotoScan. Thirdly, camera estimation was iteratively optimized with high precision GCP references until errors of GCPs and reprojection errors of tie points met desired standard. After 4 iterations, the GCP errors were stabilized and its reprojection error was down to 0.538 pixel, and the RMS reprojection error of tie points also decreased to 0.51 pixel and its maximum reprojection error was down to 7.8 pixel. Fourthly, based on the optimized camera parameters and original aerial photos, depth image of each photo was calculated and a dense gully point cloud model consisting of 9 537 948 points was built through PMVS (patch-based multi-view stereo) algorithm in PhotoScan. And fifthly, the 30 GCPs were classified into 2 categories; 10 GCPs that numbered multiples of three were selected as check points to evaluate the overall accuracy of gully model, while the others were used as geo-reference to the WGS-84 system. Finally, the georeferenced gully dense point cloud was rasterized to gully DEM (digital elevation model) and triangulated to gully TIN (triangulated irregular network) from which the gully DOM (digital ortho-photo map) was built. Afterwards, the accuracies of oblique photos derived gully point cloud model as well as DEM and DOM results were analyzed and compared with that of ortho-photos. Box plot of GCP errors verified the consistency between the X/Y/Z errors of check GCPs and reference GCPs in oblique photo result. Thus the constructed gully dense point cloud has a roughly 0.096 m planimetric RMSE and 0.018 m vertical RMSE, which fulfills the requirement of DLG (digital line graphic) and DOM in 1: 500 scale (GH/Z 3003-2010). The achieved accuracy well meets the requirement of high precision gully modeling and monitoring. The result of ortho-photos has a 0.105 m planimetric RMSE and 0.036 m vertical RMSE. That confirms a 50% improvement of vertical accuracy with oblique photos. The overall density of the gully point cloud is 12 680 points/m<sup>2</sup>, which is comparative to terrestrial laser scanning, and it avoids the uneven sampling caused by multi-station assembling of TLS (terrestrial laser scanning). Except from a small patch of inner part in concave gully head, there aren't obvious holes in gully head or walls in the model. In addition, the area covered with vegetation can also be correctly constructed. On the contrary, there are open holes in concave gully head and vegetated area in ortho-photo result. Seen from the DEM and contour lines map of the gully, the constructed terrain model gives a fine description of gully morphology. However, there are burrs and breaks in contour line caused by vegetation outside the gully, which shows the necessity of vegetation removal. In general, the proposed method has advantages in high precision gully terrain modeling and shows great ability to further application.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Aerial photography
Controlled terms:Aircraft control - Antennas - Cameras - Cloud computing - Commercial vehicles - Contour measurement - Errors - Graph theory - Image enhancement - Image processing - Iterative methods - Landforms - Laser applications - Maps - Models - Parameter estimation - Pixels - Rock mechanics - Steel beams and girders - Stereo image processing - Surface analysis - Surveying - Surveying instruments - Unmanned aerial vehicles (UAV) - Vegetation
Uncontrolled terms:Aerial photos - Commercial off the shelves - Eroded gully - Position and orientations - SfM-MVS - Terrestrial laser scanning - Triangulated irregular networks - UAV (unmanned aerial vehicle)
Classification code:405.3 Surveying - 408.2 Structural Members and Shapes - 481.1 Geology - 483.1 Soils and Soil Mechanics - 652 Aircraft and Avionics - 652.1 Aircraft, General - 662.1 Automobiles - 722.4 Digital Computers and Systems - 723.2 Data Processing and Image Processing - 742.1 Photography - 742.2 Photographic Equipment - 744.9 Laser Applications - 921.4 Combinatorial Mathematics, Includes Graph Theory, Set Theory - 921.6 Numerical Methods - 951 Materials Science
Numerical data indexing:Percentage 5.00e+01%, Size 1.05e-01m, Size 1.80e-02m, Size 3.60e-02m, Size 9.60e-02m
DOI:10.11975/j.issn.1002-6819.2018.03.012
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 38>
Accession number:20181605031862
Title:Design and performance experiment of multi-segment type auger in process of organic fertilizer production
Authors:Zhang, Xiuli (1); Liu, Yunpeng (1); Li, Lianhao (1); Tong, Zhenwei (1); Yang, Dingyuan (1); Hou, Chaopeng (1)
Author affiliation:(1) College of Mechanical & Electrical Engineering, Henan Agricultural University, Zhengzhou; 450002, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:49-56
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Organic fertilizer is obtained from animal and plant residues or waste. Organic fertilizer can improve soil fertility, and can provide comprehensive nutrition for crops. In recent years, organic waste is decomposed into organic fertilizer in a short time by using rapid fermentation technology, and the fermentation is quick and free of pollution. This technology requires homogeneous fermentation conditions in the fermentation bin. Many scholars apply the auger to the organic fertilizer fermentation equipment to stir to improve the degree of automation. In the process of organic fertilizer production, it is easy to cause the problems of blocking material, uneven mixing of materials and end accumulation by traditional auger, which affect the full fermentation, resulting in low fertilizer efficiency and poor quality. In order to solve the problems, a multi-segment type auger is designed. The device is composed of telescopic gear, feeding section, variable diameter feeding section, large diameter feeding section, discharging section and reverse rotating section. The mechanism of the material mixing uniformity is clarified by eccentric design and analyzing the movement of the telescopic gear. The anti-blocking mechanism of the device is defined through the design of variable diameter structure and the analysis of material filling degree. The problem of deposition is solved through the design and analysis of the counter rotating section. The performances of the designed multi-segment type auger and the traditional structure auger are compared with the discrete element analysis software EDEM. By comparing and analyzing the standard deviation between materials mixing degree and optimal materials mixing degree in different positions, it is derived that when the standard deviation of mixing uniformity of the material reaches 0.2, the distance required by the multi-segment type auger is 0.6 times as much as that of the traditional auger. Besides, the results also show that there exists a "dead zone" in the traditional structure auger in which the particles are difficult to contact with other particles. It causes that the minimal value of standard deviation of the materials in the traditional structure auger is about 0.04 larger than that of the materials in multi-segment type auger. By comparison and quantitative analysis of filling degree at 4 sampling positions in fermentation bin, it is derived that the degree of filling at the inlet is approximately equal, but the orientation about the degree of filling will gradually decrease and finally reach a constant value of about 0.222 in the process of materials conveying of multi-segment type auger. The change of filling degree in multi-section auger is 38.1%, and the traditional structure auger fundamentally maintains a smooth trend. The transport efficiency of the multi-segment type auger is 20% higher than that of the traditional auger. It is verified that anti-clogging ability of multi-segment type auger is so strong that it is more suitable for the production of organic fertilizer. The result of prototype test is basically consistent with the result of discrete element analysis, and the design meets the requirements of organic fertilizer production. This study can provide reference for the design of organic fertilizer production equipment.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Fertilizers
Controlled terms:Augers - Design - Efficiency - Feeding - Fermentation - Filling - Finite difference method - Machinery - Mechanization - Mixing - Problem solving - Soil testing - Statistics - Two phase flow
Uncontrolled terms:Anti-blocking mechanisms - Degree of filling - Degree of mixing - Discrete element analysis - Fermentation conditions - Fermentation technologies - Multi-segment - Traditional structures
Classification code:483.1 Soils and Soil Mechanics - 502.2 Mine and Quarry Equipment - 601 Mechanical Design - 631.1 Fluid Flow, General - 691.2 Materials Handling Methods - 802.3 Chemical Operations - 804 Chemical Products Generally - 913.1 Production Engineering - 921.6 Numerical Methods - 922.2 Mathematical Statistics
Numerical data indexing:Percentage 2.00e+01%, Percentage 3.81e+01%
DOI:10.11975/j.issn.1002-6819.2018.03.007
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 39>
Accession number:20181605031873
Title:Characteristics of soil water utilization for different stand ages of jujube trees based on<sup>18</sup>O tracking
Authors:Zhao, Xining (1, 2); Li, Nan (3); Gao, Xiaodong (1, 2); Huo, Gaopeng (3); Pan, Yanhui (4)
Author affiliation:(1) Institute of Soil and Water Conservation, Northwest A & F University, Yangling; 712100, China; (2) Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling; 712100, China; (3) College of Water Resources and Architectural Engineering, Northwest A & F University, Yangling; 712100, China; (4) Key Laboratory of Western China's Environmental Systems of Ministry of Education, Lanzhou University, Lanzhou; 730000, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:135-142
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Since the initiation of the large-scale ecological rehabilitation project by the Chinese central government in 1999, jujube forest was widely cultivated in the loess hilly region, due to its ecological and economic benefits. Soil moisture is a key factor affecting jujube growth. Clarifying water use strategy of jujube trees of different stand ages can provide useful indications for the water management of jujube forest in this area. In 2016, we selected 4 different stand ages (4, 8, 17 and 22 years) of jujube forests in a rain-fed jujube (Ziziphus Jujube cv. Lizao) plantation in Qingjian County, Shaanxi Province (37°15'N, 118°18'E). In the study, the oxygen stable isotope tracer method was used to measure the oxygen isotope ratio (δ<sup>18</sup>O) of xylem water and soil water sources in jujube orchards with 4 different stand ages, and the contribution of soil water from different depths to water uptake was estimated by the MixSIR Bayesian mixing model. The results showed that soil moisture and soil water δ<sup>18</sup>O varied across soil depths and sampling dates, which were influenced by the rainfall and evaporation. The composition of soil water isotopes and rainfall isotopes showed the same temporal trend. In arid and semi-arid areas, with the variation of soil moisture, jujube trees of different stand ages could adjust the utilization structure of soil water to adapt to the soil water environment changes. Jujube tree mainly absorbed soil water from shallow soil (0-40 cm) when soil water was available. However, when shallow soil water was scarce, jujube tree mainly absorbed the soil water from middle layer (>40-120 cm) and deep layer (>120-200 cm) with the stand age increasing, leading to the middle and deep soil water content close to wilting point (7%). In germination stage (May 29th), jujube trees mainly absorbed shallow soil water. With the increase of stand age of jujube trees, the ratio of water absorption for jujube trees from shallow soil water gradually decreased, whereas the proportion of deep soil water absorption gradually increased during flowering and fruit setting stage (July 29th), and water absorption rates in shallow layer for the 4-, 8-, 17-, and 22-year-old jujube trees were 63.58%, 78.79%, 45.03% and 11.81%, respectively. However, water absorption rates in deep layer for the 17-and 22-year-old jujube trees were 39.22% and 72.25%, respectively. In fruit enlargement period (August 26th), 4-year-old jujube trees mainly absorbed middle layer soil water, and 8-year-old jujube trees absorbed deep soil water, with absorption rate as much as 94.30%, while 17-and 22-year-old jujube trees mainly absorbed shallow soil water. During the fruit ripening period (September 25th), 8-, 17-and 22-year-old jujube trees mainly absorbed shallow, deep and middle layer soil water, respectively. The results suggest that based on soil water utilization characteristics of jujube trees with different stand ages, water management should be carried out for reducing the non-productive water consumption for 4-and 8-year-old jujube trees and the luxury water consumption for 17-and 22-year-old jujube trees, so as to ensure the sustainability of the local jujube forest and soil water use.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Water absorption
Controlled terms:Ecology - Forestry - Fruits - Isotopes - Moisture - Oxygen - Rain - Soil moisture - Soils - Sustainable development - Water conservation - Water management - Water supply
Uncontrolled terms:Arid and semi-arid areas - Ecological and economic - Ecological rehabilitation - Jujube - Oxygen isotope ratios - Oxygen stable isotopes - Stand age - Water absorption rates
Classification code:443.3 Precipitation - 444 Water Resources - 446.1 Water Supply Systems - 454.3 Ecology and Ecosystems - 483.1 Soils and Soil Mechanics - 802.3 Chemical Operations - 804 Chemical Products Generally - 821.4 Agricultural Products
Numerical data indexing:Age 1.70e+01yr, Age 2.20e+01yr, Age 4.00e+00yr, Age 8.00e+00yr, Percentage 1.18e+01%, Percentage 3.92e+01%, Percentage 4.50e+01%, Percentage 6.36e+01%, Percentage 7.00e+00%, Percentage 7.22e+01%, Percentage 7.88e+01%, Percentage 9.43e+01%, Size 0.00e+00m to 4.00e-01m
DOI:10.11975/j.issn.1002-6819.2018.03.018
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 40>
Accession number:20181605031877
Title:Monitoring model of maize lodging based on Sentinel-1 radar image
Authors:Han, Dong (1, 2); Yang, Hao (1); Yang, Guijun (1); Qiu, Chunxia (2)
Author affiliation:(1) Key Laboratory of Quantitative Remote Sensing in Agriculture of Ministry of Agriculture P. R. China, Beijing Research Center for Information Technology in Agriculture, Beijing; 100097, China; (2) College of Geomatics, Xi'an University of Science and Technology, Xi'an; 710054, China
Corresponding author:Yang, Hao(yangh@nercita.org.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:166-172
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to monitor the degree of maize lodging quickly and accurately at the regional scale, the study was conducted in Xiaotangshan National Experiment Station for Precision Agriculture, where serious maize lodging occurred on August 8, 2017, due to strong wind and heavy rain. Firstly, different backscatter indicators before and after lodging were obtained from 2 Sentinel-1A radar images. Forty-seven ground sample points were obtained. The correlation coefficients between the natural height and plant height of 32 modeling samples and their backscatter indicators were investigated to choose the best backscatter indicator of maize lodging. When the backscatter indicators were used to simulate height of samples before and after lodging directly, there was a large error between the backscatter indicators of radar and those of lower or higher plant. Therefore, to establish more accurate lodging monitoring model, firstly backscatter coefficients after lodging respectively at the channel VH and the channel VV+VH were used to build difference formula in this study. We found that backscatter coefficient after lodging at the channel VH had the best correlation with the height before lodging, and that at the channel VV+VH had the best correlation with the height after lodging. The formula's values were obtained by the simulated plant height before lodging subtracting the simulated natural height of the plant after lodging. Then, the ratio of the natural height to the plant height was used as a standard for distinguishing the degree of lodging. The results of the difference were brought into the ratio formula of natural height and plant height. By setting a reasonable ratio interval, the intervals with different degrees of lodging were separated. Finally, the lodging monitoring model was obtained. The results were verified by using the remaining 15 ground samples. The results show that lodging difference obtained by the difference formula is 100. Measured difference and simulated difference have an extremely significant relationship level (P<0.01). The classification accuracy for lodging degree is very high by using the 15 test samples and the total samples, both reaching 100%. The overall relativity between the ratio of simulated natural height to plant height and the ratio of measured natural height to plant height is 0.899. Among them, the relativity of moderate lodging is the best, followed by serious lodging, and mild lodging is the worst. The reason is that the surface vegetation in the areas of moderate lodging is not destroyed, and the surface information of the farmland is not exposed to the radar's channel. Therefore, the simplex backscatter information for plant structure makes it possible to obtain the highest accuracy. There is a large difference in plant structure before and after lodging in serious lodging areas, and the water on the ground and weeds are mixed into the information of the backscatter indicators of radar. So the accuracy will be reduced. There is only a little difference in plant structure before and after lodging in mild lodging areas, and the reset rate of mild lodging areas is better than the former 2 types of lodging. Meanwhile, the error caused by non-structural information is more. Therefore, the accuracy is the worst. The final remote sensing mapping with a high accuracy is the same as the ground field lodging condition basically. This study shows that the lodging monitoring model based on dual polarized Sentinel-1A radar image can effectively monitor the degree of maize lodging at the regional scale. It should be noted that there still are some deficiencies in this study that will be improved in the future.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Radar imaging
Controlled terms:Backscattering - Disasters - Relativity - Remote sensing - Synthetic aperture radar
Uncontrolled terms:Backscatter coefficients - Backscatter information - Classification accuracy - Correlation coefficient - Maize - Monitoring models - Polarization indices - Surface information
Classification code:716.2 Radar Systems and Equipment - 931.5 Gravitation, Relativity and String Theory
Numerical data indexing:Percentage 1.00e+02%
DOI:10.11975/j.issn.1002-6819.2018.03.022
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 41>
Accession number:20181605031890
Title:Analysis and parameter optimization of first-drying process using chain plate dryer with electromagnetic heating for green tea
Authors:Yuan, Haibo (1); Hua, Jinjie (1); Wang, Jinjin (1); Li, Jia (1); Jiang, Yongwen (1); Deng, Yuliang (1); Wang, Yueliang (2)
Author affiliation:(1) National Engineering Technology Research Center for Tea Industry, Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Hangzhou; 310008, China; (2) The Yuyao Yao Jiangyuan Tea Machinery Co., Ltd, Yuyao; 315400, China
Corresponding author:Deng, Yuliang(donny@tricaas.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:3
Issue date:January 1, 2018
Publication year:2018
Pages:265-272
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Drying is the last process in each category of tea processing, which includes first-drying and final-firing, and first-drying is more essential. The role of first-drying is evaporating water content in tea products, and more importantly, promoting the occurrence of the thermochemical reaction at the same time. The reaction promotes the transformation and improvement of quality substances, and the formation of excellent aroma, taste, color and other tea qualities. At present, the main use of first-drying technology in the current production includes hot air first-drying technology, carding machine first-drying technology, microwave first-drying technology, low temperature vacuum drying technology, and so on. Although the existing first-drying technologies can enhance the flavor and taste quality of tea with different degrees, they mostly have low thermal efficiency, inaccurate temperature controlling, uneven heat distribution, poor and unstable quality, and other issues. For these reasons, based on the hot air first-drying technology that is the most widely used, our team has adopted a new type of electromagnetic heating technology, the waste heat recovery unit and oil-air exchanger to develop the chain plate dryer with electromagnetic heat (China patent number: ZL201420816998.8), in order to enhance the tea flavor and taste quality, obtain stable and high-quality tea, and at the same time enhance the thermal efficiency and production efficiency. The structure composition and technical characteristics of this chain plate dryer with electromagnetic heat were introduced in this article. Then the parameters of this new first-drying technology of green tea were optimized. In order to explore the influence of hot air first-drying process with electromagnetic heat on the quality of green tea, based on the results of previous single factor experiments, using main biochemical composition contents of first-drying samples and sensory evaluation score of made tea as investigation index, the orthogonal design and extreme analysis were used to optimize process parameters (hot air temperature, hot air wind speed, transmission speed, and so on) of chain plate dryer with electromagnetic heat. And the new first-drying technology was compared with hot air first-drying with coal as fuel, first-drying with tea carding machine, and hot air first-drying with electric heating tube. According to the results of quality biochemical composition and sensory evaluation, the optimal first-drying parameters combination of chain plate dryer with electromagnetic heat was determined as follows: Hot air temperature was 115℃, hot air wind speed was 1 200 r/min, and transmission speed was 1 050 r/min, and the most significant factor in these 3 factors was hot air wind speed. With these process parameters, amino acids, tea polyphenols, chlorophyll, soluble sugar, catechins, and caffeine of first-drying samples reached 2.31%, 17.61%, 1.13 mg/g, 5.01%, 10.74% and 2.01%, respectively, and quality material weighted value was 7.66%, which was significantly higher than the other processes. And the shape, color, taste, and aroma of made tea with the new first-drying technology were the best and the sensory quality score was 86.40, which was significantly higher than other first-drying methods. The energy consumption was 0.76 yuan/kg, which reduced by more than 70% compared with hot air first-drying with electric heating tube; the temperature rose very rapidly, and warming time was only 10 min, which reduced by more than 50% compared with traditional hot air first-drying with coal as fuel; the design of the waste heat recovery device greatly improved the utilization rate of heat energy, and the thermal efficiency was up to 50%; and the production efficiency was 150 kg/h, which was more than 3 times higher than the traditional hot air first-drying with electric heating tube, and meanwhile, the precise and stable control of temperature and the uniform distribution of hot air established solid foundation for obtaining high quality and stable tea quality.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Drying
Controlled terms:Atmospheric temperature - Beverages - Chains - Dryers (equipment) - Electric heating - Energy utilization - Experiments - Firing (of materials) - Low temperature production - Metal recovery - Odors - Optimization - Parameter estimation - Plates (structural components) - Processing - Quality control - Sensory analysis - Speed - Temperature control - Textile industry - Textile machinery - Waste heat - Waste heat utilization - Water quality - Wind
Uncontrolled terms:Biochemical composition - Electromagnetic - Electromagnetic heating - Green tea - Orthogonal design - Single-factor experiments - Thermochemical reactions - Waste heat recovery units
Classification code:408.2 Structural Members and Shapes - 443.1 Atmospheric Properties - 445.2 Water Analysis - 525.3 Energy Utilization - 525.4 Energy Losses (industrial and residential) - 602.1 Mechanical Drives - 642.1 Process Heating - 731.3 Specific Variables Control - 819.6 Textile Mills, Machinery and Equipment - 822.3 Food Products - 901.3 Engineering Research - 913.3 Quality Assurance and Control - 913.4 Manufacturing - 921.5 Optimization Techniques
Numerical data indexing:Mass_Flow_Rate 4.17e-02kg/s, Percentage 1.07e+01%, Percentage 1.76e+01%, Percentage 2.01e+00%, Percentage 2.31e+00%, Percentage 5.00e+01%, Percentage 5.01e+00%, Percentage 7.00e+01%, Percentage 7.66e+00%, Rotational_Speed 1.05e+03RPM, Rotational_Speed 1.20e+03RPM, Time 6.00e+02s
DOI:10.11975/j.issn.1002-6819.2018.03.035
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
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
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