<RECORD 1>

Accession number:20173304051927
Title:Spatial differentiation and layout optimization of rural settlements in hill ecological protection area
Authors:Meng, Lingran (1, 2); Wu, Jun (2); Dong, Jihong (1, 3) 
Author affiliation:(1) School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou; 221116, China; (2) School of Geography and Tourism, Qufu Normal University, Rizhao; 276826, China; (3) Jiangsu Key Laboratory of Resources and Environmental Information Engineering, Xuzhou; 221116, China 
Corresponding author:Dong, Jihong(dongjihong@cumt.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:278-286
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Rural settlements are the places of habitation, production and living for rural population. Research on rural settlements can better reveal the formation of rural settlements and the relationship between the life and environment. Nowadays, the ecological environment problems caused by the rural settlement expansion and population growth have become more prominent, and the reasonable optimization of rural settlements layout and the protection of rural settlements ecological environment function are the key issues in the development of rural settlements. To clarify the spatial differentiation characteristics and optimize the layout of rural settlements in hill ecological protection area, this paper took the Sishui County, Shandong Province as a study case, and analyzed the spatial differentiation characteristics by using the nearest neighbor statistics, the spatial correlation measure model and the spatial metrics model; from 2 aspects of forest and water body based on the perspective of ecological protection and construction, the ecological protection pattern was built by using the minimum cumulative resistance model, and the optimization direction of rural settlement in Sishui county was explored. The results showed that: (1) The rural settlements of Sishui County had significant spatial distribution feature of agglomeration with the average density of 1.6-4 settlements per km²; the rural settlements mostly presented the cluster and scatter distribution in the northern and southern hilly areas, and the zonal distribution in the middle plain areas, with the spatial distribution characteristics of "dense in the north and south, sparse in the middle". (2) The majority of rural settlements in Sishui were small settlements, and the patch quantity accounted for 45.43% of the totality. There existed the rural settlements whose scale also had significantly low concentration characteristics, presenting the distribution situation of "large in the middle, small in the north and south". (3) The spatial differentiation in shape had obvious characteristics of complexity, poor continuity and fragmentation in Sishui County, and the shape of rural settlements in the middle plain areas had relatively small complexity, good continuity, and fragmentation, which was much more regular than that in the northern and southern hilly areas. (4) For the spatial distribution characteristics of the elevation, slope and river of rural settlements, it was found that the rural settlements were mainly distributed in the elevation of 73-250 m, the slope of 0-5&deg; and the range of 0-600 m away from rivers. Based on the spatial differentiation of rural settlements, the slope, roads and different land use types were selected as the most important impact factors, and the forest and water ecological protection pattern was constructed; 4 types of layout optimization i.e. key remediation, restricting expansion, moderate construction and prior development were divided according to the impact of rural settlements on forest and water, and the construction and development directions of rural settlements were explored. The results of this study can provide the basis for the planning and development of regional rural settlements under the background of ecological protection and construction. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Rural areas
Controlled terms:Ecology - Forestry - Land use - Landforms - Optimization - Population statistics - Slope protection - Spatial distribution - Spatial variables measurement
Uncontrolled terms:Hill ecological protect area - Layout optimization - Rural settlement - Sishui county - Spatial differentiation
Classification code:403  Urban and Regional Planning and Development - 454.3  Ecology and Ecosystems - 481.1  Geology - 921  Mathematics - 921.5  Optimization Techniques - 943.2  Mechanical Variables Measurements
Numerical data indexing:Percentage 4.54e+01%, Size 0.00e+00m to 6.00e+02m, Size 7.30e+01m to 2.50e+02m
DOI:10.11975/j.issn.1002-6819.2017.10.037

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 2>

Accession number:20173304051903
Title:Influences of piston structural parameters on heat transfer and temperature field of diesel engine piston
Authors:Deng, Xiwen (1); Lei, Jilin (1); Wen, Jun (1, 2); Wen, Zhigao (2); Shen, Lizhong (1) 
Author affiliation:(1) Yunnan Province Key Laboratory of Internal Combustion Engine, Kunming University of Science and Technology, Kunming; 650500, China; (2) Chengdu Galaxy Power co., LTD, Chengdu; 610505, China 
Corresponding author:Lei, Jilin(leijilin@sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:102-108
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to meet the requirements of increasingly more stringent regulations of energy conservation and emissions reduction for automotive engines, many new technologies have been applied, such as multi-valve structures, variable geometry turbochargers, exhaust gas recirculation (EGR), and electronic controlled high-pressure fuel injection systems. On the other hand, the strength of the diesel engine is higher and higher, and the temperature field distributions of the engine parts are more uneven, such as pistons and cylinder head. The optimized piston structure, the inner cooling gallery structure, and the surface coating technology have become main ways to decrease heat load and optimize the temperature distributions of piston. The phenomenon of the thermal stress concentration is caused by uneven distribution of temperature field of the piston of internal combustion engine. In order to further study the temperature field distribution of the piston, a piston of high pressure common rail diesel engine which met the emission limit of Level 5 in China was treated as the research object. Combined with the temperature test of the feature points of piston surface using hardness plug, a heat transfer model of the piston group was established by using the finite element method. The enchased ring and pin were considered in the simulation model. A temperature field of piston was obtained by using the simulation model. Through the analysis it was found that some key locations of piston were prone to thermal stress concentration, such as the upside of the pin boss, the pin hole, the piston head and the 2 oil holes. Therefore, the length of the piston pin boss, the diameter of the pin hole, the height of the top land and the distance of 2 oil holes were treated as structural parameters. The influences of piston structure on heat transfer and temperature field were analyzed by using the single parameter sweep method and the orthogonal experiment method. The study found that the temperature distribution of the piston was not uniform. The maximum temperature of 382.6&#8451; appeared at the bowl edge of combustion chamber, and the minimum temperature of 161.1&#8451; appeared at the bottom of piston skirt. The piston structures had some influence on heat transfer performance and the temperature field distribution of the piston. Among the 4 structural parameters in this study, the height of the top land had the most influence on heat transfer and temperature field, the oil hole position ranked the second, and the pin hole diameter had the minimum. The top land height had the major influences on the distribution of temperature field of piston head. The maximum temperature of the piston increased by 13.8&#8451; with the increasing of the height of the top land. On the other hand, the maximum temperature of the first groove decreased by 16&#8451; with the increasing of the height of the top land of the piston. The pin boss structure had the major impact on the regions under the oil ring and the regions of pin boss. The oil hole position had a little effect on heat transfer and temperature field of piston. In addition, if a piston structural parameter was changed, heat quantity conducted from gas side still remained almost the same. Therefore, the variation of the structure parameter could only affect heat transfer and temperature distribution of the corresponding part instead of other regions. The optimal combination of 4 structure parameters was found by the orthogonal experiment. The corresponding optimal scheme was the pin length of 72.5 mm, the diameter of the pin hole of 35 mm, the height of the top land of 8 mm, and the distance of the 2 oil holes of 53 mm. Through the heat transfer analysis it was found that the optimal scheme could reduce the maximum temperature of piston to 374.3&#8451;. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Engine pistons
Controlled terms:Combustion chambers - Cylinder heads - Diesel engines - Emission control - Engine cylinders - Engines - Exhaust gas recirculation - Finite element method - Fuel injection - Gas emissions  - Heat engines - Heat transfer - Hole concentration - Internal combustion engines - Pistons - Stress concentration - Structural optimization - Temperature - Temperature distribution - Thermal stress
Uncontrolled terms:Distribution of temperature - Exhaust gas recirculation (EGR) - High pressure common rail diesel engine - High-pressure fuel injection - Orthogonal experiment methods - Parameters - Temperature field distribution - Variable geometry turbocharger
Classification code:451.2  Air Pollution Control - 612  Engines - 641.1  Thermodynamics - 641.2  Heat Transfer - 654.2  Rocket Engines - 701.1  Electricity: Basic Concepts and Phenomena - 921.5  Optimization Techniques - 921.6  Numerical Methods - 931.2  Physical Properties of Gases, Liquids and Solids
Numerical data indexing:Size 3.50e-02m, Size 5.30e-02m, Size 7.25e-02m, Size 8.00e-03m
DOI:10.11975/j.issn.1002-6819.2017.10.013

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 3>

Accession number:20173304051918
Title:Planting area extraction of winter wheat based on multi-temporal SAR data and optical imagery
Authors:Zhou, Tao (1); Pan, Jianjun (1); Han, Tao (1); Wei, Shanbao (2) 
Author affiliation:(1) College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing; 210095, China; (2) College of Public Administration, Nanjing Agricultural University, Nanjing; 210095, China 
Corresponding author:Pan, Jianjun(jpan@njau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:215-221
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Wheat is one of the most important crops for many countries. It is important to obtain accurate wheat planting area. Optical imagery has been widely used in crop classification and made great progress, but the optical imagery in the critical period of wheat growth is often affected by weather and other external conditions. In contrast, synthetic aperture radar (SAR) is potentially effective data source for wheat mapping because of its all-weather, all-day imaging capabilities. The study site was located in a typical urban agricultural region in Gaochun District of Nanjing, the provincial capital of Jiangsu Province, China, with the central coordinates of 118&deg;52&prime;E and 31&deg;19&prime;N. Six SAR (Sentinel-1A) and 4 optical (Landsat-8) images were obtained from the ESA during the growing period of winter wheat. The objective of this study was to explore the abilities of multi-temporal satellite SAR data, optical images and the combination of both types of images to identify winter wheat in an urban agriculture region with complex planting structures. The investigations were through the following steps: 1) The texture features were extracted from the SAR images using the gray level co-occurrence matrix (GLCM), and the backscatter intensity data were also obtained; 2) A support vector machine (SVM) was used as the classifier to map winter wheat, using the different combinations of the Sentinel-1A derived information and optical images. 3) Then, the classification accuracies for different combinations of SAR variables and optical images were evaluated. The results showed that: 1) In the process of winter wheat growth, the backscatter characteristics changed obviously. In the middle of April, the backscatter characteristics were different between winter wheat and other vegetation in the study area, which could provide the theoretical basis for winter wheat classification. 2) Using single polarization, single-temporal SAR data were difficult to meet the accuracy requirements of winter wheat with complex planting structures, and the classification accuracy of VV polarization was higher than that of VH polarization; 3) Compared with VV polarization, the producer's and user's accuracy of VV+VH combination were increased by 27.3% and 13.6%, respectively. When VV polarization was added to VH backscatter intensity images, the producer's and user's accuracy were increased from 50.3% to 85.7% and from 54.5% to 87.9%, respectively; 4) When texture images were added to backscatter intensity images, the winter wheat fields could be mapped with a satisfactory classification accuracy, and the user's and producer's accuracy could reach up to 94.6% and 93.3%, respectively; 5) The combination of multi-temporal SAR and optical images had the best classification accuracy, and the producer's and user's accuracy were 97% and 98.4% (overall accuracy 95.3%, Kappa coefficient 0.91), respectively. The addition of multi-temporal SAR to optical images allowed us to increase producer's and user's accuracy of winter wheat by 3.7% and 3.8%, respectively. The results in this paper show that the satisfactory classification of winter wheat can be achieved using Sentinel-1A data alone in urban agricultural regions with complex planting structures. In addition, texture features of SAR can improve SAR data classification accuracy. The SAR and optical images can make use of the advantages of information complementation of each other to make up for their deficiencies in crop classification. It is indicated that the SAR data can not only be used as a data source instead of optical images to distinguish winter wheat, but also as a supplementary data source to improve the classification accuracy of optical data. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Radar imaging
Controlled terms:Acoustic devices - Agricultural machinery - Agriculture - Backscattering - Classification (of information) - Crops - Geometrical optics - Image texture - Polarization - Radar  - Remote sensing - Space-based radar - Support vector machines - Synthetic aperture radar - Urban growth
Uncontrolled terms:Backscatter intensity - Classification accuracy - External conditions - Gray level co occurrence matrix(GLCM) - Imaging capabilities - Optical imagery - SAR data classification - Winter wheat
Classification code:403.1  Urban Planning and Development - 716.1  Information Theory and Signal Processing - 716.2  Radar Systems and Equipment - 723  Computer Software, Data Handling and Applications - 723.2  Data Processing and Image Processing - 741.1  Light/Optics - 752.1  Acoustic Devices - 821  Agricultural Equipment and Methods; Vegetation and Pest Control
Numerical data indexing:Percentage 1.36e+01%, Percentage 2.73e+01%, Percentage 3.70e+00%, Percentage 3.80e+00%, Percentage 5.03e+01% to 8.57e+01%, Percentage 5.45e+01% to 8.79e+01%, Percentage 9.33e+01%, Percentage 9.46e+01%, Percentage 9.53e+01%, Percentage 9.70e+01%, Percentage 9.84e+01%
DOI:10.11975/j.issn.1002-6819.2017.10.028

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 4>

Accession number:20173304051909
Title:Evaluation of water use efficiency in Yellow River Irrigation Area based on flow-tracing and layered-weight method
Authors:Feng, Feng (1, 2); Ni, Guangheng (3); Meng, Yuqing (4) 
Author affiliation:(1) Yellow River Conservancy Technical Institute, Kaifeng; 475004, China; (2) Small Watershed Hydraulic Technology Research Center of Henan Provincial Colleges and Universities, Kaifeng; 475004, China; (3) Department of Hydraulic Engineering, Tsinghua University, Beijing; 100086, China; (4) Eastern Water Conservancy Bureau of Henan Province Sanyizhai Branch Office, Kaifeng; 475300, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:145-153
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:There is an obvious gap between China's current irrigation water use efficiency and the world's advanced level for that of China is only 0.50, whereas that of world's advanced level reaches 0.7-0.8. Therefore, saving water resources, improving agricultural irrigation water efficiency, and ensuring the irrigation efficiency will be a long-term strategic task in the future of China. The purpose of this paper was to make a comprehensive evaluation for water use efficiency of Yellow River irrigation area based on flow-tracing and multiple weights method. In order to make a good comprehensive evaluation for water using efficiency, an open index-evaluation system including 19 deterministic index and 3 sub-systems based on irrigation flow-tracing method. Then, the improved fuzzy evaluation model was constructed based on multiple layer-weight determination method by making use of multi-objective and multi-level system. In the first layer (input layer), the index weight was confirmed by calculating entropy-weight-vector, and in the second layer (criterion layer), the sub-system weight was confirmed by the entropy- weight-vector method, equal-weight method and experience weight method, respectively for multi-layer weights. Finally, obtaining data and comparing different weights from the evaluation results was carried out by the fuzzy evaluation model. The paper took Sanyizhai Irrigation Area in lower reaches of the Yellow River as a case study. Sanyizhai Irrigation Area is located in the eastern plain of Henan Province (34&deg;52&prime;N, 144&deg;44&prime;E), north of the Yellow River. Sanyizhai Irrigation Area was founded in 1958, and it involves 18 counties scattered in Kaifeng, Shangqiu and Heze in Henan Province, and Shandong Provinces as well. Up to now, the water-diverting capacity of Sanyizhai Irrigation Area is about 150 m³/s, and irrigation area covers 9 counties(districts) mainly in the eastern part of Henan province, that is: Kaifeng, Lankao and Qi counties of Kaifeng City, Minquan County, Ningling County, Suiyang District, Liangyuan District, Sui County and Yucheng County of Shangqiu City respectively. The total land area of Sanyizhai Irrigation Area reaches 4 344.2 km²and the total cultivated area is 2 701.42 km². The paper took 10 years data from 2005 to 2014 of Sanyizhai Irrigation Area as a case study to make a comprehensive evaluation for water use efficiency. The 3 kinds of weight was used for the calculation. The results showed that: the first entropy-weight-vector weight was 0.307, 0.348, 0.345, the second equal-weight was 0.333, 0.333, 0.334, and the third subjective weight was 0.400, 0.200, 0.400. The evaluation result presented a general identical trend and showed that weight-influence was very limited for the evaluation result. According to the evaluation result, the irrigation water effect in 2013 was optimal among 10 years with average value 0.993 by comprehensive evaluation. Meanwhile, this evaluation results were in conformity with the actual situation of Sanyizhai Irrigation Area. In 2013 the rainfall and groundwater is relatively small, whereas the practical diverted irrigation intake and irrigation area has kept high level, which has ensured irrigation effect of and crop-harvest. According to the evaluation value of second layer, the dynamic variation process about engineering factors and management factors could be seen clearly, which showed that it kept a low-level development before 2007 and entered into a higher level development after 2009, so it could help us find the existing problems in irrigation process and provides data basis and technical support for the scientific planning and sustainable development of Yellow River Irrigation Area. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Water resources
Controlled terms:Efficiency - Entropy - Groundwater - Irrigation - Planning - Precipitation (chemical) - Rivers - Water - Water supply
Uncontrolled terms:Flow-tracing - Improved fuzzy models - Irrigation area - Layered-weight - Water use efficiency
Classification code:444  Water Resources - 444.2  Groundwater - 446.1  Water Supply Systems - 641.1  Thermodynamics - 802.3  Chemical Operations - 821.3  Agricultural Methods - 912.2  Management - 913.1  Production Engineering
Numerical data indexing:Age 1.00e+01yr, Area 3.44e+08m2, Area 7.01e+08m2
DOI:10.11975/j.issn.1002-6819.2017.10.019

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 5>

Accession number:20173304051902
Title:Analysis and test of torque characteristics for force balance and multi input gear motor
Authors:Wen, Desheng (1); Pan, Weiyuan (1); Shi, Zizhou (1); Shang, Xudong (1); Ma, Guanglei (1); Gu, Pan (1) 
Author affiliation:(1) College of Mechanical Engineering, Yanshan University, Qinhuangdao; 066004, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:94-101
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the development of economy, hydraulic transmission is an indispensable part of national economy. Hydraulic actuator is the core part of hydraulic transmission, and the gear motor has the advantages of small size, light weight, and strong adaptability to the harsh working conditions, and has a very important role in hydraulic actuator. But gear motor's torque fluctuation is larger, and there are unbalanced radial force, trapped oil phenomenon and big noise, so it is difficult to develop. Based on these reasons, in this paper, a force balance type multi input gear motor is proposed, which has 3 internal motors and 3 outer motors in one case, the inner and outer motors are evenly distributed on the output shaft, and the radial force of the output shaft is balanced by the output shaft, which can significantly reduce the total force on the gear shaft and the bearing, and help to improve the service life and the mechanical efficiency of the bearing. Each motor has an independent oil distribution device, their work does not affect each other, and a motor can output 4 kinds of torques and rotational speeds through different connection modes as follows: The internal motor works independently, the outer motor works separately, the internal and external motors work together, and differential connection of internal and external motors. As an actuator, hydraulic motor's torque and rotational speed can be achieved with the function of the liquid pressure which the hydraulic pump provide, and the hydraulic motor output torque ripple is an important indicator to measure the performance of hydraulic motors. And it is an important index to measure the stability of hydraulic system. The torque ripple of a single gear motor is related to the number of teeth of the meshing gear, and when the motor rotates one tooth, the torque has a pulse. The force balance type multi input gear motor has a plurality of motors at work at the same time, which is different from the torque ripple produced by a single motor working. When the internal motor is working independently, the difference of the position of the initial meshing point for the 3 internal motors is successively one third of tooth. By the superposition of the torque, the torque ripple of the 3 internal motors can be reduced, but the torque pulsation cycle is changed to 1/3. When internal motor and outer motor work together, on the basis of the same pulse period of the internal and external motors, the position of the initial meshing point of the inner and outer motor gear teeth is different from that of the gear teeth, the maximum value and the minimum value are added, and the torque ripple is minimized. For differential connection of internal and external motors, the motor is equivalent to the pump; under the same pulse period, the position of the initial meshing point of the internal and external motor is the same, and the input flow of the internal and outer motor is offset by each other, so as to minimize the torque ripple. Therefore, when working with a single motor, the torque ripple is related to the number of teeth in the meshing gear, and when a plurality of motors work together, the torque ripple is mainly related to the torque pulsation period of the motor and the position of the initial meshing point of the motor. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Hydraulic actuators
Controlled terms:Actuators - Bearings (machine parts) - Gear teeth - Gears - Hydraulic equipment - Hydraulic motors - Motors - Optical pumping - Torque - Torque control
Uncontrolled terms:Differential connection - Force balances - Mechanical efficiency - Multiinput - Torque characteristic - Torque fluctuation - Torque pulsation - Unbalanced radial forces
Classification code:601.2  Machine Components - 632.2  Hydraulic Equipment and Machinery - 731.3  Specific Variables Control - 732.1  Control Equipment - 931.2  Physical Properties of Gases, Liquids and Solids
DOI:10.11975/j.issn.1002-6819.2017.10.012

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 6>

Accession number:20173304051922
Title:Identification for operating pelagic light-fishing vessels based on NPP/VIIRS low light imaging data
Authors:Guo, Ganggang (1, 2); Fan, Wei (1); Xue, Jialun (1, 2); Zhang, Shengmao (1); Zhang, Heng (1); Tang, Fenghua (1); Cheng, Tianfei (1) 
Author affiliation:(1) Key Lab of East China Sea &amp; Oceanic Fishery Resources Exploitation and Utilization, Ministry of Agriculture, East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai; 200090, China; (2) College of Marine Sciences, Shanghai Ocean University, Shanghai; 201306, China 
Corresponding author:Cheng, Tianfei(chengtianfeinuist@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:245-251
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Fishing data are the basement of fisheries science research, but currently the source of fishing data is extraordinarily scarce, and data quality is poor in some aspects. Satellite low light sensors can detect the light-fishing vessels at night, however, its application in pelagic fishery has been limited by the lack of an algorithm for extracting the location and brightness of operating pelagic light-fishing vessels. An examination of operating pelagic light-fishing vessels features in the day/night band (DNB) image, which was from the visible infrared imaging radiometer suite (VIIRS) on the Suomi National Polar-orbiting Partnership (NPP) satellite, indicated that the features were a list of nonadjacent bright spots. In order to identify the operating pelagic light-fishing vessels from VIIRS/DNB accurately, we designed a set of identification algorithm for operating pelagic light-fishing vessels according to the light radiation characteristics of its fishing gathering lamps in NPP/VIIRS low light image. Before applying the identification algorithm, a data pre-processing step was adopted through radiation stretch and noise reduction by adaptive Wiener filter to prepare the data for further analysis and use. A spike median index (SMI) was used to enlarge the radiation difference between operating pelagic light-fishing vessel pixels and background pixels. On the basis of this, an adaptive threshold segmentation method called the maximum entropy (MaxEnt) method was used to extract the bright spot pixels, and generated a list of candidate operating pelagic light-fishing vessels detections. The candidate pixels were then filtered to remove the false identification bright spot pixels distributed near the operating pelagic light-fishing vessel pixels, and illuminated by the high-power fishing gathering lamps by a local spike detection (LSD) algorithm. A validation study was conducted at a night with weak lunar illuminance on May 24, 2015 which was selected randomly, using the vessel monitoring system (VMS) data of Chinese operating light-seiners vessels on the high seas of Northwest Pacific Ocean light seine fishing ground and the result of VIIRS/DNB image visual interpretation. The validation result showed that the identification algorithm detected 27 operating pelagic light-fishing vessels on the high seas of Northwest Pacific Ocean light seine fishing ground, and the number of operating pelagic light-fishing boats and their distribution were entirely consistent with the result of VIIRS/DNB image visual interpretation; the VMS data had the record of 25 operating pelagic light-fishing vessels among the total 27 vessels, and their distribution was nearly the same with the result of identification algorithm and VIIRS/DNB image visual interpretation. The identification algorithm worked well when lunar illuminance was weak and its identification accuracy was above 92%. The identification algorithm not only avoided the subjectivity and uncertainty of certain threshold segmentation, but also removed the false identification bright spot pixels near the operating pelagic light-fishing vessel pixels, which were illuminated by the high-power fishing gathering lamps. Detection of operating pelagic light-fishing vessels based on VIIRS/DNB imaging data can provide up-to-date activity and change information of operating pelagic light-fishing vessels for pelagic light-fishing industry, which meets the need of fishing boat's daily monitoring, and has a wide application prospect in fishing effort estimation, research of central fishing ground spatial-temporal distribution and change, and fishery forecast and management. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Fishing vessels
Controlled terms:Adaptive filters - Boats - Data handling - Fisheries - Image processing - Infrared imaging - Lighting - Maximum entropy methods - Monitoring - Noise abatement  - Oceanography - Orbits - Pixels - Remote sensing - Thermography (imaging)
Uncontrolled terms:Adaptive threshold segmentation - DNB image - Identification algorithms - Night-time lights - NPP/VIIRS - Spatial-temporal distribution - Vessel monitoring systems - Visible infrared imaging radiometer suites
Classification code:471.1  Oceanography, General - 674.1  Small Marine Craft - 716.1  Information Theory and Signal Processing - 723.2  Data Processing and Image Processing - 742.1  Photography - 746  Imaging Techniques - 751.4  Acoustic Noise
Numerical data indexing:Percentage 9.20e+01%
DOI:10.11975/j.issn.1002-6819.2017.10.032

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 7>

Accession number:20173304051913
Title:Relationship between matric potential, moisture migration and frost heave in freezing process of soil
Authors:Xue, Ke (1, 2); Wen, Zhi (1); Zhang, Mingli (3); Li, Desheng (1, 2); Gao, Qiang (1, 2) 
Author affiliation:(1) State Key Laboratory of Frozen Soil Engineering, Northwest Institute of Eco-Environmental and Resources, Chinese Academy of Sciences, Lanzhou; 730000, China; (2) University of Chinese Academy of Sciences, Beijing; 100049, China; (3) College of Civil Engineering, Lanzhou University of Technology, Lanzhou; 730050, China 
Corresponding author:Wen, Zhi(wenzhi@lzb.ac.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:176-183
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The moisture migration from unfrozen region to freezing front is the main factor that causes frost heave during soil freezing, it is generally believed that the energy difference between two positions in soil drives the liquid water migrate to frozen region and leads water redistribution when soil freezing. However, limited by technical means, the matric potential measurement in frozen soil is still an open problem. In this study, the relationship between matric potential, soil water content and frost heave was investigated by using the newly introduced pF meter matric potential sensor and the 5TM water content sensor that could liquid water content and matric potential in one-dimension saturated soil freezing. The results showed the temperature field change caused the change of the liquid pore water phase into the ice, led the destruction of the initial energy equilibrium in different position of the soil sample, and then caused the liquid water migrated from high potential area to a relatively low potential area. During the freezing experiment, we found that the 16-cm depth of the soil sample began to freeze when the experiment had been conducted for 4 hours, and the freezing was from top to deep soil. When the experiment had been conducted for 4 hours, the freezing arrived at 10-cm depth of the soil sample, and the frozen depth kept unchanged. After the experiment, the water content in 10-14 cm of the soil sample could reach as high as about 55%, and at the 6 cm soil sample height, the liquid water content in the unfrozen region reduced to 25.8%, which supported the moisture movement upwards to the upper part of the soil sample. The frost heave process of saturated soil could be divided into 3 stages: 1) In 0-4 h, the frost heave amount was smaller; 2) In 4-60 h, the frost heave amount increased rapidly and the segregation ice began to grow, the moisture migration process were active; 3) The growth of segregation ice tended to stabilize and the liquid water stopped migrating to the freezing front; Similarly, the soil matric potential would have response to the change of the liquid water content and the moisture migration during the freezing process. In the early stage of freezing, the liquid water content in frozen region decreased, and the soil matric potential below the freezing front lasted for 0. When the freezing had been conducted for 20 h, the soil matric potential near the upper cooling plate reached about -1 000 kPa, and the soil matric potential in 14, 12, 10 cm of the soil samples was -55, -47.5, -30.2 kPa, respectively. When the freezing rate slowed down and the segregation ice began to grow, the liquid water tended to migrate upward, meanwhile, the soil matric potential below the freezing front decreased continuously, which were due to the liquid water migration from the unfrozen region to the frozen region. Results supported the moisture migration required 2 conditions: the matric potential difference between 2 positions in soil and the sufficient time. After the experiment, the distribution of the water content in the soil was consistent with that of the segregation ice lens. In the frozen region, the liquid water content was approximately linear with the temperature gradient, and in unfrozen region, the liquid water content was related to the amount of migrated moisture, but not related to the temperature gradient. The results provide an experimental basis for understanding frost heave mechanism and the establishment of frost heave model. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Soil surveys
Controlled terms:Freezing - Frozen soils - Ice - Liquids - Moisture - Segregation (metallography) - Soil mechanics - Soil moisture - Soils - Temperature  - Thermal gradients - Water content
Uncontrolled terms:Freezing experiments - Frost heave amounts - Frozen heave - Liquid water content - Matric potential - Soil matric potential - Temperature field change - Water redistribution
Classification code:483.1  Soils and Soil Mechanics - 531.2  Metallography - 641.1  Thermodynamics
Numerical data indexing:Percentage 2.58e+01%, Percentage 5.50e+01%, Pressure -1.00e+06Pa, Pressure -3.02e+04Pa, Size 1.00e-01m, Size 1.00e-01m to 1.40e-01m, Size 1.60e-01m, Size 6.00e-02m, Time 0.00e+00s to 1.44e+04s, Time 1.44e+04s, Time 1.44e+04s to 2.16e+05s, Time 7.20e+04s
DOI:10.11975/j.issn.1002-6819.2017.10.023

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 8>

Accession number:20173304051914
Title:Analysis on frost resistance and damage mechanism of aeolian sand concrete
Authors:Wu, Junchen (1, 2); Shen, Xiangdong (1) 
Author affiliation:(1) College of Water Conservancy and Civil Engineering, Inner Mongolia Agricultural University, Huhhot; 010018, China; (2) College of Civil Engineering and Architecture, Inner Mongolia Technical College of Construction profession, Huhhot; 010070, China 
Corresponding author:Shen, Xiangdong(ndsxd@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:184-190
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:At present, the insufficient storage of the river sand and the rising cost of the construction have been unable to meet the requirements of the concrete projects in the desert area and the surrounding irrigated area. However, this condition can be greatly alleviated by the use of the rich desert sand in the surrounding irrigated area in Hetao region of Inner Mongolia, which is also known as the aeolian sand. Therefore, it is of great significance to conduct the research on the frost resistance of aeolian sand concrete (ASC), which can be an type of alternative material widely used in the construction of water conservancy projects in the cold northwest region, such as irrigated canal lining and the dam. In this paper, 5 types of C25 aeolian sand concretes were designed according to the percentage of the river sand quality replaced by aeolian sand, i.e. 20%, 40%, 60%, 80%, and 100%, which were compared with the ordinary Portland cement concrete (OPC) with the same strength. The frost resistance of these 6 types of concretes was studied through the acceleration test method in the Structure Laboratory of Inner Mongolia Agricultural University, and finally the damage laws of ordinary concrete and aeolian sand concrete were demonstrated. In addition, the damage mechanism of aeolian sand concrete under freeze-thaw conditions was analyzed by using the testing measures such as environmental scanning electron microscope (ESEM), strain monitoring, X-ray diffraction analysis (XRD), nuclear magnetic resonance (NMR), and so on. At the beginning of freeze-thaw, the increase of ettringite did make the structure of concrete dense, but the internal frost heaving force caused the continuous extension of micro cracks and pores at the end of freeze-thaw. As a result, the ASC containing 60% aeolian sand showed the layered dissection on the surface, and the dynamic modulus of elasticity increased first and then decreased, which proved the internal damage was growing gradually. After the freeze-thaw cycle worked, the residual strain of ASC of 60% was the largest and the residual strain of the 6 groups of concretes was 60%&gt;40%&gt;0%&gt;100%&gt;20%&gt;80%. This result indicated that the internal stress caused by the 6 types of concretes through freeze-thaw cycle of 8 times was sufficient to lead to cracks in the matrix. What was more, the porosity and permeability of ASC of 20% and 40% were much larger. As for 6 types of concretes, the porosity of ASC of 60% was relatively small. However, the phenomenon of porosity increasing appeared with the increasing of the amount of mixed aeolian sand, which indicated the more the closed pore in the concrete, the lower the permeability. All the results indicated that the damage occurred when the freeze-thaw cycle of aeolian sand concrete whose amount was no more than 40% reached 100 times, while the ordinary concrete could withstand 125 times. Both of them showed the expansion of cracking and the rapid decline of quality and dynamic modulus of elasticity. Nevertheless, the freeze-thaw time that the aeolian sand concrete could withstand increased when the mixing amount of aeolian sand reached 60%-100%. At the same time, the frost resistance of concrete was improved obviously and the damage was characterized by a layered dissection on the surface. Besides, the frost resistance was the best when the mixing amount of aeolian sand reached 100%, because the aeolian sand concrete had a mass of closed capillaries and an inhibiting effect on suffering freeze-thaw damage. For this reason, it can certainly withstand the highest freeze-thaw cycle times. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Concretes
Controlled terms:Concrete mixing - Concrete testing - Cracks - Dissection - Dynamics - Elastic moduli - Failure (mechanical) - Freezing - Frost resistance - Irrigation  - Mixing - Nuclear magnetic resonance - Porosity - Portland cement - Sand - Scanning electron microscopy - Thawing - Water management - X ray diffraction analysis
Uncontrolled terms:Aeolian sand - Damage - Dynamic modulus of elasticity - Environmental scanning electron microscopes - Freeze-thaw - Nuclear magnetic resonance(NMR) - Stain - X-ray diffraction analyses (XRD)
Classification code:412  Concrete - 412.1  Cement - 461.6  Medicine and Pharmacology - 483.1  Soils and Soil Mechanics - 802.3  Chemical Operations - 821.3  Agricultural Methods - 931.2  Physical Properties of Gases, Liquids and Solids - 951  Materials Science
Numerical data indexing:Percentage 1.00e+02%, Percentage 2.00e+01%, Percentage 4.00e+01%, Percentage 6.00e+01% to 1.00e+02%, Percentage 6.00e+01%, Percentage 8.00e+01%
DOI:10.11975/j.issn.1002-6819.2017.10.024

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 9>

Accession number:20173304051926
Title:Desertification monitoring and early warning in context of sandy land consolidation
Authors:Han, Yiwen (1); Liu, Zhong (1); Yu, Xueqian (1); Wang, Jiaying (1) 
Author affiliation:(1) College of Resources and Environment, China Agricultural University, Beijing; 100193, China 
Corresponding author:Liu, Zhong(lzh@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:271-277
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to ensure China's food and ecological security, it's particularly necessary to perform desertification monitoring and early warning during the land consolidation projects execution. The study area was located in Kezuohouqi which is famous for the sandy land. Based on Landsat 8 OLI image data, desertification monitoring was achieved by the decision tree classification method. The desertification early warning system was constructed by PSR (pressure-state-response) model; the natural and human influencing factors of desertification were regarded as "pressure", the desertification monitoring results were regarded as "state", and the land consolidation projects were regarded as "response". The weight of each factor in the PSR model was set by expert scoring method, and DESI (desertification ecological security index) was adopted in this paper; the greater the index, the lower the risks of desertification. Based on the DESI, the results of desertification early warning were divided into 4 different levels through natural breakpoint method, namely, no desertification warning, slight desertification warning, medium desertification warning and severe desertification warning. In the end, the validity of land consolidation could be evaluated through calculating the area of different desertification early warning results in the land consolidation projects and conducting the comparison. The results showed that: 1) The area of desertification accounted for 88% of study area. To be exact, the area of medium and severe desertification accounted for 61% of the total area, and the extremely severe desertification was mainly concentrated in the western part of the study area whose area accounted for 6% of the total area. 2) The zonal differentiation of desertification early warning results was clear; the spatial distribution from east to west in Kezuohouqi in turn was no desertification warning, medium desertification warning, slight desertification warning, medium desertification warning, severe desertification warning, and then medium desertification warning. The area of medium desertification warning was the largest, and the distribution laws of severe warning desertification and extremely severe desertification were similar, but the severe warning desertification tended to gather in the northwest pastoral areas of Kezuohouqi, the slight warning and no warning areas were located in the eastern part of Kezuohouqi, and the land use pattern was mainly agricultural land. 3) In the land consolidation projects, high quality capital farmland construction and arable land consolidation were mainly distributed in the areas with no desertification warning. The potential land suitable for agriculture and the project of land reclamation were mainly distributed in slight desertification warning area and medium desertification warning area. There was the sever desertification warning land among the farmland consolidation, the potential land resources suitable for agriculture, and forage grass base construction projects, whose distribution style was sporadic. However, the severe desertification warning area in high quality capital farmland was not up to the mark and should be eliminated from the projects. Overall, in the context of land consolidation, the risk of further desertification is small. The severe desertification warning area would be a key point for land consolidation projects, and the government must put a high premium on the sever warning area. The results of desertification early warning in this paper can provide the reference for land consolidation and adjustment. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Climatology
Controlled terms:Agriculture - Consolidation - Decision trees - Ecology - Farms - Land reclamation - Land use - Remote sensing - Trees (mathematics) - Vegetation
Uncontrolled terms:Construction projects - Decision tree classification - Desertification monitoring - Early warning - Early Warning System - Farmland consolidations - Pressure state response (PSR) - Psr models
Classification code:403  Urban and Regional Planning and Development - 442.2  Land Reclamation - 443  Meteorology - 454.3  Ecology and Ecosystems - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 921.4  Combinatorial Mathematics, Includes Graph Theory, Set Theory
Numerical data indexing:Percentage 6.00e+00%, Percentage 6.10e+01%, Percentage 8.80e+01%
DOI:10.11975/j.issn.1002-6819.2017.10.036

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 10>

Accession number:20173304051917
Title:Analysis and application of drought characteristics based on run theory and Copula function
Authors:Wang, Xiaofeng (1, 2); Zhang, Yuan (1, 3); Feng, Xiaoming (3); Feng, Yu (4); Xue, Yayong (1, 3); Pan, Naiqing (3) 
Author affiliation:(1) School of Earth Sciences and Resources, Chang'an University, Xi'an; 710054, China; (2) School of Land Engineering, Chang'an University, Xi'an; 710054, China; (3) State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, CAS, Beijing; 100085, China; (4) School of Urban and Environmental Sciences, Liaoning Normal University, Dalian; 116029, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:206-214
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Drought is a complex and recurrent climate phenomenon, and understanding the development of the drought event is of great significance in preventing the damage. Current studies have analyzed the drought duration and severity based on run theory and Coupla function but few focuses on the drought recurrent interval and its relationship with agricultural drought disaster. In this study, the drought recurrence interval was investigated based on the drought duration and severity using run theory and Coupla function and the results were applied to agricultural drought disaster analysis in order to verify the reliability of the method for agricultural application. The study area was Northern Shannxi and the precipitation data from 1960 to 2015 were collected for drought grade classification based on standardized precipitation index (SPI). The drought duration and severity of drought event was calculated based on SPI values using run theory. Each drought characteristic index was evaluated for its distribution by comparing 7 different distributions. Then, the joint distribution of the 2 indices was established based on their correlation. Then the recurrence interval of each index was calculated for determination of their joint recurrence interval. The agricultural disaster area data were obtained from Statistic Yellow Book. The results showed that the drought occurred 94-103 times in 1960-2015 in the Northern Shannxi. The main drought area with high frequency was the area such as Yunlin, Yanan et al and that with low frequency was in the area such as Baoji, Xian, Xianyang et al. The distribution of drought duration and severity belonged to Weibull and Gamma distribution, respectively. The joint function of the 2 indices could be well fitted by the Frank-copula function with smaller squared euclidean distance and akaike information criterions. With the increase of drought duration and severity, the joint probability and recurrence interval gradually increased. The joint recurrence interval variation of different meteorological stations had different changing trend. The actual drought- affected area of the crops in the Northen Shannxi was closely related to the drought duration and severity. The drought events joint recurrence interval was coincide with the actual drought disaster situation in the region. In the period of 1995-2005, the actual and theoretical drought duration was consistent mostly and the absolute errors between the actual and theoretical drought recurrence interval were only 0.1-0.3 a. The results indicated that the method proposed here was reliable in analyzing drought characteristics and could be used for agricultural drought disaster assessment. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:38
Main heading:Drought
Controlled terms:Agriculture - Disasters - Precipitation (chemical) - Reliability analysis - Reliability theory - Weibull distribution
Uncontrolled terms:Agricultural drought disasters - Akaike information criterion - Copula functions - Different distributions - Northern Shannxi - Run theory - Squared euclidean distance - Standardized precipitation index
Classification code:444  Water Resources - 802.3  Chemical Operations - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 922.2  Mathematical Statistics
DOI:10.11975/j.issn.1002-6819.2017.10.027

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 11>

Accession number:20173304051908
Title:Automatic measurement of greenhouse tomato evapotranspiration based on negative pressure irrigation system
Authors:Li, Yinkun (1, 2); Xue, Xuzhang (1, 2); Zhao, Qian (1, 2); Guo, Wenzhong (1, 2); Sun, Weituo (1, 2); Chen, Xiaoli (1, 2); Chen, Hong (1, 2) 
Author affiliation:(1) Beijing Research Centre of Intelligent Equipment for Agriculture, Beijing; 100097, China; (2) Key Laboratory of Urban Agriculture (North China), Ministry of Agriculture, Beijing; 100097, China 
Corresponding author:Guo, Wenzhong(guowz@nercita.org.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:137-144
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Accurately measuring crop evapotranspiration is important for developing suitable irrigation schedule and improving crop water use efficiency. In order to obtain the crop evapotranspiration conveniently, rapidly and accurately, the negative pressure irrigation (NI) system based on negative pressure device was established in this study. In combination with negative pressure device, we increased the liquid level detection device, which could collect the liquid level information real-timely, and the evapotranspiration was calculated by formula with system controller. The new method of crop evapotranspiration measurement could avoid many problems, i.e. high cost on measurement, high-intensity work and poor accuracy and so on. To test and verify the accuracy of calculation results, 2-seasons (early-spring season and autumn-winter season) field experiments were carried out at the National Experiment Station for Precision Agriculture (40&deg;10&prime;43&Prime;N, 116&deg;26&prime;39&Prime;W), Xiaotanshan Beijing, China. The NI measured results were compared with those with the water balance method; (CK). The soil water content in surface (0-20 cm), soil water storage (0-100 cm) and tomato yield were measured in the experiment during the whole growing season. The dynamic change of soil water content in greenhouse was studied and the tomato evapotranspiration and water use efficiency were compared. The results showed that: the variation of surface soil water content (0-20 cm) and soil water storage (0-100 cm) were stable under the negative pressure irrigation condition and the annual variation range were 21.4%-23.8% and 322.2-333.3 mm, respectively. The seasonal variation regularity of tomato evapotranspiration could be obtained with the method of negative pressure irrigation. The variation of early-spring tomato evapotranspiration in greenhouse showed a single peak curve under the negative pressure irrigation condition. The seasonal change ranged from 0.46 mm to 5.68 mm, and the peak appeared at May 20^th. The autumn-winter tomato evapotranspiration had a seasonal change of 0.56-3.43 mm, which was less than the early-spring season, and the peak appeared at October 12^th. Compared with the water balance method, the tomato evapotranspiration of the negative pressure irrigation system had taken on the same change rule during the growth period, and the maximum water consumption rate all appeared at tomato fruit-set period. The annual tomato evapotranspiration was 533.4 mm based on the method of negative pressure irrigation with no significant difference with that of the water balance method (541.6 mm) (P&gt;0.05). The tomato evapotranspiration that measured by the 2 methods (NI and CK) had showed a extremely significantly linear positive correlation (R²=0.971, P&lt;0.01), and the mean of absolute of relative error was 3.83%-7.71%, and the mean of absolute of absolute error was only 2.14- 5.08 mm. Water use efficiency of greenhouse tomato for the NI treatment was 293.3 and 292.4 kg/mm in the early spring and autumn winter seasons, respectively and there were no significant difference compared with CK treatment (P&gt;0.05). The method based on negative pressure irrigation system can make the calculation of crop evapotranspiration conveniently, which not only had no significant difference with those of the water balance method, but also simply, low cost, rapidly and with high accuracy. This method provides an effective technology to measure crop evapotranspiration in solar greenhouse. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Water supply
Controlled terms:Crops - Efficiency - Evapotranspiration - Fruits - Greenhouses - Irrigation - Soil moisture - Soils
Uncontrolled terms:Automatic measurements - Crop evapotranspiration - Irrigation systems - Liquid level detection - Positive correlations - Tomato - Water balance method - Water consumption rate
Classification code:446.1  Water Supply Systems - 483.1  Soils and Soil Mechanics - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 913.1  Production Engineering
Numerical data indexing:Linear_Density 2.92e+05kg/m, Linear_Density 2.93e+05kg/m, Percentage 2.14e+01% to 2.38e+01%, Percentage 3.83e+00% to 7.71e+00%, Size 0.00e+00m to 1.00e+00m, Size 0.00e+00m to 2.00e-01m, Size 2.14e-03m to 5.08e-03m, Size 3.22e-01m to 3.33e-01m, Size 4.60e-04m to 5.68e-03m, Size 5.33e-01m, Size 5.42e-01m, Size 5.60e-04m to 3.43e-03m
DOI:10.11975/j.issn.1002-6819.2017.10.018

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 12>

Accession number:20173304051930
Title:Numerical simulation and experiment of pressure and temperature field for jet impinging ramie fiber separation and degumming
Authors:Shao, Yunguo (1); Su, Gongbing (1); Zou, Shuchang (1); Meng, Xiuping (1) 
Author affiliation:(1) School of Mechanical Engineering and Automation, Wuhan Textile University, Wuhan; 430073, China 
Corresponding author:Su, Gongbing(sgb6710@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:302-309
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to research and develop a new technology of ramie fiber splitting and residual gum removal, ramie fibers treated by alkali scouring with 10.8% residual gum content were selected as the research object. A hydraulic dynamic device was trial-manufactured for investigating the ramie fiber splitting and residual gum removal. According to the trial results, an equipment with a high temperature (373 K) water-jet function was designed and manufactured. Firstly, without consideration of interaction among factors, orthogonal experiments with 3 factors and 3 levels were carried out using the equipment with single nozzle to inspect the influence of jet distance, inlet pressure, and treating time on the residual gum content. The results showed that the optimal combination was 30 mm jet distance, 1.2 MPa inlet pressure, and 16 min treating time, and the jet distance was the primary factor. Under the optimal conditions, residual gum rate was 3.1%. Secondly, under the conditions of the inlet pressure of 1.2 MPa, the outlet diameter of 2.0 mm, and the temperature of 373 K, the distribution of both temperature field and pressure field, and the effective area on ramie fiber surface by the treatment of water-jet impact with single nozzle were simulated using the FLUENT software, with different jet distance of 20, 30, 40 and 50 mm. The numerical simulation results indicated that with 30 mm jet distance, the pressure field on ramie fiber surface was in a range from 0.16 to 0.30 MPa, which was consistent with the outcomes of hydraulic dynamic impact experiment as well as the orthogonal experiments. Thus, it hinted that the jet distance at 30 mm was the most effective condition for the ramie fiber splitting and residual gum removal. Meanwhile, the inlet pressure at 1.2 MPa, the outlet diameter of 2.0 mm, the temperature at 373 K, the jet distance at 30 mm, and the internal space between nozzles ranging from 20, 30 to 40 mm were set to simulate the effective area on ramie fiber surface by the treatment of water-jet impact with double nozzles. The numerical simulation results suggested that the optimal internal space between nozzles was 30 mm, and the pressure field and temperature field on ramie fiber surface were from 0.2 to 0.3 MPa and from 320 to 334 K respectively. Under the optimal conditions, it had a better overlap area and a maximum coverage of pressure field. Eventually, the residual gum content and fiber breaking force were applied to assess the fiber quality after treatment. Based on the single nozzle trial results and the data analyses, jet distance was the most impactful factor. According to the optimal internal space between nozzles of 30 mm, multi tests were carried out with jet distance of 20, 30, 40 and 50 mm and treating time of 12, 14, 16 and 18 min. The results stated that the optimal internal space was 30 mm and the optimal treating time was 16 min, which acquired 3.1% residual gum content and 51.71 cN singe-fiber breaking force. According to the results of numerical simulation and equipment practices, it suggested that the fiber splitting and residual gum removal of the pre-degumming ramie fiber were satisfactorily achieved at one time, without fiber damage ascribed to the flexible property of water within a certain pressure extent. This technology not only can combine the stages of fiber splitting, bleaching, and rinsing in the existing process, but also provides a novel technology for researching and developing equipment for ramie fiber splitting and gum removal. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Fighter aircraft
Controlled terms:Computer simulation - Degumming - Equipment - Fibers - Hemp - Hydraulic machinery - Jets - Nozzles - Numerical models - Pressure  - Temperature - Water treatment
Uncontrolled terms:Hydraulic dynamics - Jet impingement - Optimal combination - Optimal conditions - Orthogonal experiment - Pressure and temperature - Ramie - Splitting
Classification code:445.1  Water Treatment Techniques - 631.1  Fluid Flow, General - 632.2  Hydraulic Equipment and Machinery - 641.1  Thermodynamics - 652.1.2  Military Aircraft - 723.5  Computer Applications - 821.4  Agricultural Products - 901  Engineering Profession - 921  Mathematics - 931.1  Mechanics
Numerical data indexing:Percentage 1.08e+01%, Percentage 3.10e+00%, Pressure 1.20e+06Pa, Pressure 1.60e+05Pa to 3.00e+05Pa, Pressure 2.00e+05Pa to 3.00e+05Pa, Size 2.00e-03m, Size 3.00e-02m, Size 3.00e-02m to 4.00e-02m, Size 4.00e-02m, Size 5.00e-02m, Temperature 3.20e+02K to 3.34e+02K, Temperature 3.73e+02K, Time 1.08e+03s, Time 9.60e+02s
DOI:10.11975/j.issn.1002-6819.2017.10.040

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 13>

Accession number:20173304051910
Title:Sterilization and alkalinity-hardness removal effect by using electrochemical method for reclaimed water used in drip irrigation
Authors:Zhang, Ning (1); Li, Yunkai (2); Si, Buchun (1); Shen, Ruixia (1); Liu, Zhidan (1) 
Author affiliation:(1) Laboratory of Environment-Enhancing Energy and Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture, College of Water Resources and Civil Engineering, China Agricultural University, Beijing; 100083, China; (2) College of Water Resources and Civil Engineering, China Agricultural University, Beijing; 100083, China 
Corresponding author:Liu, Zhidan(zdliu@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:154-160
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Reclaimed water is becoming more and more important for irrigation due to water deficits, however, the ions and microbes in reclaimed water can lead to physiochemical or biological fouling of drip irrigation. There are physical, chemical, biological methods on controlling emitter clogging. In principle, electrolysis supply allows electrical forces to inhibit the formation of fouling. Electrochemical water treatment technology is a clean and environmentally friendly method to prevent emitter clogging compared to chlorination added in reclaimed water because it only uses electricity as power and few poisonous materials are produced. This study investigated the sterilization and alkalinity-hardness removal effect of electrochemical water treatment technology for reclaimed water in order to provide a possible method for reclaimed water treatment used in drip irrigation that could prevent emitter clogging. An electrochemical system was designed, which included a power supply, a pump, a cylindrical upflow low-voltage electrolysis reactor and inlet and effluent bottles. The electrolysis reactor used Ti/ SnO<inf>2</inf>+Sb<inf>2</inf>O<inf>3</inf>and stainless steel as the anode and cathode, and the volume of electrolysis reactor was 1.5 L, the high-aspect ratio was 4:1. The following 2 experiments are designed: 1) the treatment time was 12 h, and the voltage was maintained at 0.5, 2 and 4 V; 2) the voltage was 4 V, and the treatment time was maintained at 3, 6, 12, 24, 48 h; all the experiments were repeated 3 times. The total number of bacteria, total hardness, total alkalinity, pH value, concentration of chlorine was measured before and after electrochemical water treatment. And then we calculated the sterilization rate, removal rate of hardness, the removal rate of alkalinity, the variation of chlorine to evaluate the possibility of electrochemical methods in dealing with ions and microbes. The results showed that besides the applied voltage and treatment time, the accumulated treatment time was also a key factor for electronic water treatment technology. When the accumulated treatment time was below 100 h, the amount of bacteria was very low, and the sterilization rate was more than 80%. The biggest removal rate of hardness and the alkalinity was 23.94% and 66.85%, respectively, which was found when the applied voltage was 4 V and the treatment time was 48 h, and at the same time the accumulated treatment time was 160 h. This result demonstrated that electrochemical water treatment technology had a positive effect on controlling emitter clogging. With the increasing of accumulated treatment time, especially when the accumulated treat time was more than 320 h, there was a significant decline on sterilization rate and removal rate of hardness. The amount of bacteria was increased, and the sterilization rate was below 0 correspondingly. The anode (Ti/SnO<inf>2</inf>+Sb<inf>2</inf>O<inf>3</inf>) was not stable for long-term operation especially when the accumulated treat time was more than 320 h. The sterilization rate and removal rate of hardness and alkalinity was better when the accumulative treatment time was 160 h than it was 320 h. Further study is needed to improve the robustness of the electrolysis reactor and find the reason why Ti/ SnO<inf>2</inf>+Sb<inf>2</inf>O<inf>3</inf>anode lost effectiveness. To apply the electrochemical water treatment in practice, the improvement of anode materials and performance is also needed. The lowcost of electrochemical water treatment provides an economic basis for its application. This primary investigation demonstrated the electrochemical method has the potential for the inhibition of irrigation fouling. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:39
Main heading:Chemicals removal (water treatment)
Controlled terms:Alkalinity - Anodes - Aspect ratio - Bacteria - Chlorine - Effluents - Electric power systems - Electrochemistry - Electrodes - Electrolysis  - Hardness - Irrigation - Microorganisms - pH - Produced Water - Reclamation - Stainless steel - Sterilization (cleaning) - Water treatment
Uncontrolled terms:Biological fouling - Biological methods - Drip irrigation - ELectrochemical methods - Electrochemical systems - Re-claimed water - Total alkalinities - Water treatment technologies
Classification code:445.1  Water Treatment Techniques - 452.3  Industrial Wastes - 461.9  Biology - 545.3  Steel - 706.1  Electric Power Systems - 714.1  Electron Tubes - 801.1  Chemistry, General - 801.4.1  Electrochemistry - 804  Chemical Products Generally - 821.3  Agricultural Methods - 951  Materials Science
Numerical data indexing:Percentage 2.39e+01%, Percentage 6.68e+01%, Percentage 8.00e+01%, Time 1.15e+06s, Time 1.73e+05s, Time 3.60e+05s, Time 4.32e+04s, Time 5.76e+05s, Voltage 4.00e+00V, Volume 1.50e-03m3
DOI:10.11975/j.issn.1002-6819.2017.10.020

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 14>

Accession number:20173304051906
Title:Mosaic of crop remote sensing images from UAV based on improved SIFT algorithm
Authors:Jia, Yinjiang (1); Xu, Zhenan (1); Su, Zhongbin (1); Jin, Siyu (1); Rizwan, Arshad M. (1) 
Author affiliation:(1) School of Electronic Engineering and Information, Northeast Agricultural University, Harbin; 150030, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:123-129
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The technology of unmanned aerial vehicle (UAV) remote sensing takes the UAV as a remote sensing platform and the digital equipment as the mission payload. UAV is characterized by high mobility, low cost and automated acquisition of the remote sensing data. These characteristics of UAV can be used to acquire high resolution images, and therefore, they are widely used in precision agriculture, pest forecasting, crop yield prediction, and so on. However, due to the restrictions of acquisition equipment and flight height, the task area may not be fully covered in acquired images. So it is necessary to mosaic the gathered image. In the process of using the scale-invariant feature transform (SIFT) algorithm for the mosaic of crop remote sensing images, the feature points were few and the effect of mosaic was poor because of the low contrast of the crop remote sensing images. To solve this problem, the contrast experiment was conducted for analyzing the steps of SIFT algorithm using the low altitude crop remote sensing images of past years. It was noted that the images were blurred because of Gaussian transform in the stage of image preprocessing and Gaussian pyramid constructing, which led to the lack of the feature points. Aiming at this problem, we proposed to use a sharpening filter to highlight the details of the image and increase the number of feature points after the Gauss transform. In the stage of searching feature points, after analyzing the feature points on the same scale, we found the feature points concentrated in the regions where the color changed obviously; while in the different scales, the overall distribution of the feature points was inversely proportional to the scale. To prevent the reduction of the feature points caused by the same sampling step in the regions of high scale, in this paper, a search method of feature points based on adaptive sampling step was used to achieve uniform distribution of the feature points, because the uniform distribution of feature points was more conducive to image mosaic. A larger sampling step was used in the low-scale region and a smaller sampling step was used in the high-scale region. In the phase of feature matching, the feature points of crop remote sensing images were mostly concentrated at the minimum value, and a few maximum points often did not affect the image matching effect, but it would increase the amount of calculation. Therefore, this paper adopted non-minimum suppression to improve the efficiency of the algorithm. In order to verify the validity of the proposed algorithm, we carried out the experiment based on UAV remote sensing platform from July to August in 2016. Through the contrast experiment using SIFT algorithm and proposed algorithm, we could see that, as for low altitude crop remote sensing images, the number of feature points was averagely increased by 77.5% after optimization, the distribution of feature points was also more uniform, the number of matching points averagely increased by 15 pairs and the matching rate averagely increased by 9.46%; for the crop images that could not be stitched by SIFT algorithm, the proposed algorithm could extract more than 8 pairs of matching points, and this satisfied the condition of image mosaic. Experiments have showed that the custom sharpening filter can extract more feature points, and after introducing the adaptive sampling step, the distribution of the feature points is more uniform, and the optimized algorithm keeps the robustness. Therefore, this algorithm is more suitable for the crop remote sensing images mosaic than SIFT algorithm. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Remote sensing
Controlled terms:Agriculture - Crops - Gaussian distribution - Image acquisition - Image processing - Image reconstruction - Optimization - Robustness (control systems) - Unmanned aerial vehicles (UAV)
Uncontrolled terms:Acquisition equipments - High resolution image - Image mosaic - Non-minimum suppression - Precision Agriculture - Remote sensing platforms - Sampling steps - Scale invariant feature transform algorithms (SIFT)
Classification code:652.1  Aircraft, General - 723  Computer Software, Data Handling and Applications - 731.1  Control Systems - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4  Agricultural Products - 921.5  Optimization Techniques - 922.1  Probability Theory
Numerical data indexing:Percentage 7.75e+01%
DOI:10.11975/j.issn.1002-6819.2017.10.016

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 15>

Accession number:20173304051894
Title:Improved design and test of key components for longitudianl axial flow combine harvester
Authors:Wang, Jinshuang (1); Xiong, Yongsen (1); Xu, Zhongwei (2); Ma, Guang (1); Wang, Zhiming (1); Chen, Dejun (1) 
Author affiliation:(1) College of Mechanical and Electrical Engineering, Jinhua Polytechnic, Jinhua; 321017, China; (2) Zhejiang Sifang Co., Ltd., Yongkang; 322000, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:25-31
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In view of the current state that the crawler-type vertical axial flow combine harvester can not be quickly converted between different crops, small radius steering is easy to cause surface soil damage, non-differential threshing drum is not suitable for high yield crop threshing, and without anti vibration water treatment the screen surface can not adapt to the cleaning processing of the crop with high water content, the loss rate of the cutting table is high, the threshing separation ability is poor, and the power consumption is high, we have improved the design and experiment of the main working parts such as cutting, threshing, cleaning and walking parts. The cutting table was designed to be a stepless speed adjustable telescopic structure, the threshing device was designed to be a longitudinal-axis roller with the same diameter and different speed, and a single HST (hydro static transmission) in situ steering walking device and an anti adhesion cleaning device were adopted. The results of laboratory tests and field tests showed that: The retractable cutting table could realize the fast conversion between the rice/wheat harvest state and the rape harvest state, and enlarge the use function of the cutting table; the loss of rapeseed was significantly reduced, and compared with the conventional method, the loss rate of rape was reduced by 2.8 percentage point. The threshing and separating device with the same diameter and differential speed could make use of the different speed of the threshing cylinder, and the threshing effect and separation ability were improved at the same time. Compared with the equal length single speed axial flow roller, the net loss rate of entrainment and removal decreased by 0.02 percentage point and 0.09 percentage point respectively, and the crushing rate was reduced by 0.017 percentage point. When the steering wheel was turned to a single side in wet field, the brake track was dragged on the surface of the ground, and the mud was accumulated. However, when a single hydraulic motor was used to steer the transmission, the steering would not occur. The conventional steering mechanism realized the steering with one side of the track brake, and consumed the braking power considerably; the in-situ steering had no braking, and both sides of the track were reversed. In-situ steering mechanism reduced surface soil damage and steering power consumption, and the power consumption was reduced by 37% when the steering was replaced by the single side. Cleaning mechanism and cleaning sieve after water repellent treatment shook board surface, which improved wet grain cleaning performance, and the loss rate was reduced by 0.9 percentage point and the impurity rate was reduced by 0.4 percentage point. The improved design of the main working equipment of the combine harvester improves the working performance of the whole machine. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:19
Main heading:Harvesters
Controlled terms:Agriculture - Axial flow - Brakes - Cleaning - Crops - Cutting - Design - Electric power utilization - Experiments - Hydraulic machinery  - Hydraulic motors - Speed - Water treatment
Uncontrolled terms:Conventional methods - Hydrostatic transmission - Longitudianl axis flow - Performance - Steering mechanisms - Threshing and separating - Water repellent treatment - Working performance
Classification code:445.1  Water Treatment Techniques - 602  Mechanical Drives and Transmissions - 631.1  Fluid Flow, General - 632.2  Hydraulic Equipment and Machinery - 706.1  Electric Power Systems - 802.3  Chemical Operations - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 901.3  Engineering Research
Numerical data indexing:Percentage 3.70e+01%
DOI:10.11975/j.issn.1002-6819.2017.10.004

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 16>

Accession number:20173304051907
Title:Influence of shape and size on flow rate of microporous concrete irrigation emitters
Authors:Li, Xiangming (1); Yang, Jianguo (1) 
Author affiliation:(1) College of Water Resources and Architecture Engineering, Northwest A&amp;F University, Yangling; 712100, China 
Corresponding author:Yang, Jianguo(yjg632003@nwsuaf.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:130-136
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Microporous concrete irrigation emitters possess excellent hydraulic performance. The influence of opening porosity on the flow rate of the microporous concrete irrigation emitters has been studied in detail, while the influence of structural shape and parameters on the flow rate of microporous concrete irrigation emitters remains unclear. The water requirement of different crops could be satisfied by adjusting the opening porosity to change the flow rate of the microporous concrete irrigation emitters. In order to make the further improvement of irrigation effect and make rational use of the microporous concrete irrigation emitters, the study in this paper was focused on revealing the influence of shape and parameters on the flow rate of microporous concrete irrigation emitters. We took sands and cement as raw materials and silica solution as adhesive, and prepared 2 kinds of microporous concrete specimens with mean pore size of 2.5-2.6 &mu;m, opening porosity of 20.3%-20.5% and flexural strength of 3.2 MPa by using a combined technique of dry pressing and atomizing humidifying curing, and then 2 types of irrigation emitters were made by assembling the disk and tube specimens respectively in plastic casings. The irrigation emitters were installed on the hydraulic performance test platform, and then the flow rate of the 2 types of irrigation emitters was measured. By changing the water head of the hydraulic performance test platform, the diameter and thickness of the disk, the length, diameter and wall thickness of the tube, the influence of structural shape and parameters on the flow rate of microporous concrete irrigation emitters was studied systematically. For the disk-type irrigation emitters, the flow rate increased with the increase of disk diameter while decreased with the increase of disk thickness, the flow rate per unit area depended completely on the disk thickness but had nothing to do with the disk diameter. When the water head was 3 m, the flow rate per unit area of the disk-type irrigation emitters decreases gradually from 40.5 mL/(h&middot;cm²) to 25.7 mL/(h&middot;cm²) as the disk thickness increased from 5 mm to 20 mm. For the tube-type irrigation emitters, the flow rate increased gradually with the increase of length and diameter of the tube while it decreased gradually with the increase of wall thickness, the flow rate per unit area was great impacted by both diameter and the wall thickness of the tube. Basically, the flow rate per unit area of the tube-type irrigation emitters decreased obviously with the increase of wall thickness but increased gradually with the increase of tube diameter. Though the thickness of disk and tube was the same, the flow rate per unit area of the tube-type irrigation emitters was always lower than that of the disk-type irrigation emitters. As the tube diameter increased, the flow rate per unit area of the tube-type irrigation emitters increased gradually and got closer and closer to the flow rate per unit area of the disk-type irrigation emitters. When the water head was 3 m, as the tube diameter increased from 60 mm to 120 mm, the flow rate per unit area of the tube-type irrigation emitters with wall thickness of 5, 10, 15, 20 mm increased gradually and reached to their respective theoretical value of 40.5, 35.4, 30.6 and 25.7 mL/(h&middot;cm²). The results in this paper provide valuable information for scientific use of microporous concrete irrigation emitters. In the actual process of irrigation, according to the results in this study, selecting and using microporous concrete irrigation emitters with suitable shape and parameters will be conducive to water absorption of crop, and also be helpful to improve water-saving effect of the microporous concrete irrigation emitters. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Microporous materials
Controlled terms:Concretes - Crops - Flow rate - Irrigation - Microporosity - Pore size - Porosity - Structural frames - Structure (composition) - Subirrigation  - Tubes (components) - Water absorption - Water conservation
Uncontrolled terms:Combined techniques - Concrete specimens - Hydraulic performance - Irrigation effects - Microporous - Shapes - Theoretical values - Water requirements
Classification code:408.2  Structural Members and Shapes - 412  Concrete - 444  Water Resources - 619.1  Pipe, Piping and Pipelines - 631  Fluid Flow - 802.3  Chemical Operations - 821.3  Agricultural Methods - 821.4  Agricultural Products - 931.2  Physical Properties of Gases, Liquids and Solids - 951  Materials Science
Numerical data indexing:Percentage 2.03e+01% to 2.05e+01%, Pressure 3.20e+06Pa, Size 2.00e-02m, Size 2.50e-06m to 2.60e-06m, Size 3.00e+00m, Size 5.00e-03m to 2.00e-02m, Size 6.00e-02m to 1.20e-01m
DOI:10.11975/j.issn.1002-6819.2017.10.017

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 17>

Accession number:20173304051897
Title:Experiment and vibration suppression algorithm for high-branch pruning manipulator based on fuzzy PID with improved PSO
Authors:Li, Yang (1, 2); Hou, Jialin (1, 2); Yuan, Jin (1, 2); Zhao, Xinxue (1); Liu, Xuemei (1, 2); Zhang, Li (3) 
Author affiliation:(1) College of Mechanical &amp; Electronic Engineering, Shandong Agricultural University, Tai'an; 271018, China; (2) Shandong Provincial Key Laboratory of Horticultural Machinery and Equipment, Tai'an; 271018, China; (3) Department of Resources and Civil Engineering, Shandong University of Science and Technology, Tai'an; 271019, China 
Corresponding author:Hou, Jialin(jlhou@sdau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:49-58
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Pruning trees is an important work in forestry production, which plays an important role on the growth of trees and timber and the forest fire prevention. However, domestic and foreign high-altitude pruning machinery is still in its infancy, whose working height is generally less than 8 m and is not high flexible. It is difficult to effectively improve work efficiency in pruning high branches. In this paper, a simple, low-cost mobile tall tree pruning machine was designed, which could be easily towed to the forest area, and prune high branches within 15 m height. This machine had the working radius of 6 m and the maximum pruning diameter of 10 cm. However, in the process of sawing and positioning, due to the long arm span and high load weight ratio, there were obviously flexible features for its arms, and the end-effector (pruning saw) was easy to vibrate during its positioning. Thus, it was difficult to achieve fast and accurate positioning, as well as fix the branch to be cut. Aiming to the above problems, this paper analyzed the flexible characteristics of the boom system with the boom display and the high load weight ratio. On this basis, the vibration suppression control method of the end of pruning saws was investigated to achieve the rapid and accurate positioning of the end of pruning saws. In this paper, focusing the flexible characteristics of the manipulator and the vibration suppression of the end-point, based on the introduction of the boom structure and working principle, we analyzed the impact of flexible features on the positioning of the end of pruning saws by geometric derivation, and the FEM (finite element modeling) was used for the dynamics analysis of the boom system. And the fuzzy PID (proportion, integral, derivative) controller was designed based on an improved PSO (particle swarm optimization) algorithm, in order to realize the active vibration suppression control of the end of the actuator. In the designed fuzzy PID controller, the improved PSO algorithm was used on the numerical simulation model to optimize the fuzzy domain intelligently. The parameters of the PID controller were adjusted and the vibration of the pendulum saw was suppressed, and the simulation and experimental verification were performed in the SIMULINK environment and a prototype system, respectively. The experimental results showed that the design of the tall trees pruning manipulator control method could realize the end-point vibration suppression, and the pruning saw could be accurately positioned into the steady state during the localization process in a short period of time. The actual measured data showed that the overshoot was less than 50% under the open-loop state, the amplitude decay was less than 5% of the peak after 1 s, the vibration adjustment time was less than 1 s, and the system could achieve steady state, and achieve a more effective vibration suppression effect. Verification results showed that under the effect of the control algorithm and the controller designed in this paper, the end-effector could be stabilized in a short time after the positioning to achieve better active vibration suppression effect. The control algorithm improved the pruning saw's positioning accuracy and speed, and optimized the dynamic performance of the entire machinery to ensure the flexible control of high branch pruning machinery. Through the simulation analysis and prototype test using the proposed active control algorithm, the results verify the reliability of the algorithm and accumulate the valuable experience for the further development of the high branch pruning machinery. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Vibration analysis
Controlled terms:Controllers - Cutting - Deforestation - Electric control equipment - End effectors - Finite element method - Fireproofing - Fires - Flexible displays - Forestry  - Machinery - Manipulators - Optimization - Particle swarm optimization (PSO) - Point contacts - Proportional control systems - Reliability analysis - Three term control systems - Timber - Vibration control
Uncontrolled terms:Flexible Features - Forestery - Fuzzy-PID - Improved PSO - Vibration suppression
Classification code:704.1  Electric Components - 722.2  Computer Peripheral Equipment - 731  Automatic Control Principles and Applications - 732.1  Control Equipment - 914.2  Fires and Fire Protection - 921.5  Optimization Techniques - 921.6  Numerical Methods
Numerical data indexing:Percentage 5.00e+00%, Percentage 5.00e+01%, Size 1.00e-01m, Size 1.50e+01m, Size 6.00e+00m, Size 8.00e+00m, Time 1.00e+00s
DOI:10.11975/j.issn.1002-6819.2017.10.007

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 18>

Accession number:20173304051924
Title:Effects of cattle manure composting methods on greenhouse gas and ammonia emissions
Authors:Zhu, Xinmeng (1); Dong, Wenyi (1); Wang, Hongyuan (2); Yan, Changrong (1); Liu, Hongbin (2); Liu, Enke (1) 
Author affiliation:(1) Institute of Environment and Sustainable Development in Agriculture, CAAS/Key Laboratory of Dry Land Agriculture, MOA, Beijing; 100081, China; (2) Institute of Agricultural Resources and Regional Planning in Agriculture, CAAS/Key Laboratory of Nonpoint Source Pollution Control, MOA, Beijing; 100081, China 
Corresponding author:Liu, Enke(liuenke@caas.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:258-264
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Composting is an environmentally friendly technology for treating livestock manure by transforming organic matter into more stable and nutritional fertilizer. However, composting is also a significant source of CH<inf>4</inf>, CO<inf>2</inf>, N<inf>2</inf>O and NH<inf>3</inf>gases if proper composting methods are not used. The production of these gases not only reduces the agricultural value of the final compost but also aggravates some environmental problems such as global warming, which reduces the environmental benefits of composting. Four types of composting methods are used extensively, namely farmer compost (FC), covering compost (CC), covering-turning compost (CTC) and covering and aeration-turning compost (CATC). Concerns about climate change have increased the demand for strategies to minimize greenhouse gas and ammonia emissions. However, the greenhouse gas and ammonia emissions from the 4 composting methods during composting have received little attention. The purpose of this study was to analyze the greenhouse gas and ammonia emissions from the composting of dairy manure with these 4 types of composting methods. These results will assist the identification of better composting methods with the potential to mitigate greenhouse gas and ammonia emissions. The evolution of CH<inf>4</inf>, CO<inf>2</inf>, N<inf>2</inf>O and NH<inf>3</inf>and maturity index were monitored in 4 composting mixtures in Dali Prefecture, Yunnan Province. Gas samples were taken at various stages of composting from December 2015 to February 2016, and the period was over 64 days. The results showed that the CATC resulted in the most desirable maturity, and effectively reduced CH<inf>4</inf>and N<inf>2</inf>O emissions. However, this composting method did not reduce CO<inf>2</inf>and NH<inf>3</inf>emissions from the cumulative gaseous emissions. Under the CC conditions, CH<inf>4</inf>emissions increased by 48.7% compared with the FC; however, N<inf>2</inf>O and NH<inf>3</inf>emissions from the CC were similar to the FC, which resulted from covering with a plastic film. Although the CTC improved the maturity of the final compost, this method was also featured with the increased emissions of CH<inf>4</inf>, CO<inf>2</inf>, and NH<inf>3</inf>. Throughout the study period, the CATC released the lowest amount of total greenhouse gas (CH<inf>4</inf>and N<inf>2</inf>O) (18.0 kg/t), followed by the FC (25.6 kg/t), CC (32.9 kg/t), and CTC (38.1 kg/t). The total greenhouse gas (CH<inf>4</inf>and N<inf>2</inf>O) emissions of the CC and CTC were 1.8 and 2.1 times as high as that of CATC at the time of maturity, respectively. The greenhouse gas and ammonia emissions varied substantially with time and were significantly correlated with temperature. The pH values of the compost could significantly affect the emissions of N<inf>2</inf>O and NH<inf>3</inf>, which indicated a potential way to mitigate greenhouse gas and ammonia emissions through proper compost management. Compared with other composting methods, the CATC showed the greatest potential to mitigate the overall greenhouse effect, and a greater maturity than the other 3 composting methods. Moreover, the lower cost and operational convenience of CATC could allow this method to be easily put into practice. Among the 4 composting methods, covering and aeration-turning compost (CATC) is considered to be a superior composting method, which should be promoted among farmers. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Gas emissions
Controlled terms:Agriculture - Ammonia - Carbon dioxide - Climate change - Composting - Fertilizers - Gases - Global warming - Greenhouse effect - Greenhouse gases  - Manures - Temperature control
Uncontrolled terms:Ammonia emissions - Environmental benefits - Environmental problems - Environmentally-friendly technology - Livestock manure - Maturity - Maturity indices - Yunnan province
Classification code:443.1  Atmospheric Properties - 451.1  Air Pollution Sources - 731.3  Specific Variables Control - 804  Chemical Products Generally - 804.2  Inorganic Compounds - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 821.5  Agricultural Wastes
Numerical data indexing:Age 1.75e-01yr, Percentage 4.87e+01%
DOI:10.11975/j.issn.1002-6819.2017.10.034

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 19>

Accession number:20173304051900
Title:Structure design of sweeping type bionic olfactory detection chamber and its flow field performance simulation and verification
Authors:Wen, Tao (1); Dong, Shuai (1); Gong, Zhongliang (1); Li, Lijun (1); Zheng, Lizhang (1); Sang, Mengxiang (1) 
Author affiliation:(1) School of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha; 410004, China 
Corresponding author:Gong, Zhongliang(gzlaa@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:78-85
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The detection chamber is an important part of the bionic olfactory detection analysis instrument. Unreasonable structure design of detection chamber can cause gas vortex and prolong the sensors' response and recovery time. Non-uniform distribution of airflow field can cause inconsistence of the sensor array in numerical induction. Therefore, it is significant to explore the characteristics of gas flow and distribution, optimize the flow field structure, improve the uniformity and stability of the flow rate and advance the accuracy and repeatability of olfactory detection chamber. However, the traditional method of further manufacture design improvements requires long transformation time, and high costs, and the measurement range is usually disappointing. Computational Fluid Dynamics (CFD) can provide detailed information on airflow simulation and ensure convenient design of agricultural equipments. In order to optimize the structure of bionic olfactory detection chamber of sweeping type, and improve the uniformity and stability of fluid velocity distribution, based on the differential equations of fluid motion, the internal flow field of olfactory detection chamber was numerically simulated by using the CFD. This paper proposed the models of 3 types of chamber detection original structures, and the uniformity and stability of olfactory sensors' detection area from the optimal model were compared with the test results. The 3 types of detection chamber original structures were linear arrangement, parallel arrangement and structure of multi nasal ducts. Each model design was mainly composed of an intake pipe, a detection chamber, a sensor array and a vent pipe. The fluid flow rate was much smaller than the acoustic velocity and the fluid flow was considered as an incompressible process inside the chamber. In the process of olfactory detection, the fluid flowed into the detection chamber from the intake pipe and flowed out of the vent pipe, so the inlet boundary was set to velocity inlet. Outlet pressure boundary conditions were selected, and the natural pressure was taken as the boundary value. The fluid temperature in the chamber was room temperature which was 26 &#8451;. The wall had no slip boundary condition, and was assumed to be a rigid wall without considering the influence of wall elasticity. The speed deviation ratio and the nonuniformity coefficient were chosen as comprehensive evaluation indicators. The velocity distribution in chamber flow field was obtained and used to analyze the original structures to provide the preference design. The detection chamber of multi nasal ducts corresponded to inclination model. The simulation results indicated that the structures of detection chamber influenced air velocity distribution. The detection chamber of multi nasal ducts along the pipe axis (0.035-0.049 m range) had a velocity smooth region, the velocity of which was stabilized merely at 0.018-0.268 m/s, which could meet the requirement of detection condition. There were no velocity smooth regions in the linear arrangement, and the airflow velocity of smooth regions in parallel arrangement merely ranged from 0.001 to 0.018 m/s. The detection chamber of multi nasal ducts showed the advantage in the uniform and stability of velocity, of which the maximum values of speed deviation ratio and nonuniformity coefficient were calculated to be 0.830 6 and 0.292, respectively. Meanwhile, in the gas detection period by the numerical simulation, the detection time of 3 models was 223.4, 302.0 and 213.8 s, respectively, and the minimum value of the structure of multi nasal ducts showed that it had fast flow response and high working efficiency. Moreover, the optimum structure could effectively improve the consistency of the sensors' numerical detection, and the standard deviation and the coefficient of variation ranged from 0.153 5 to 0.428 3 and from 0.030 5 to 0.082 7, respectively. The results provide a reference for the uniformity design of flow field structures similar to the detection chamber. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Structural design
Controlled terms:Acoustic wave velocity - Acoustic wave velocity measurement - Air - Bionics - Boundary conditions - Computational fluid dynamics - Computer simulation - Differential equations - Ducts - Electronic nose  - Equations of motion - Error detection - Flow fields - Flow of fluids - Flow of gases - Incompressible flow - Models - Numerical models - Sensors - Stability  - Structural optimization - Velocity - Velocity distribution
Uncontrolled terms:Accuracy and repeatabilities - Air velocity distributions - Coefficient of variation - Detection chambers - No-slip boundary conditions - Olfactory - Performance analysis - Response and recovery time
Classification code:408.1  Structural Design, General - 461.1  Biomedical Engineering - 631.1  Fluid Flow, General - 631.1.2  Gas Dynamics - 723.5  Computer Applications - 751.1  Acoustic Waves - 801  Chemistry - 804  Chemical Products Generally - 921  Mathematics - 922.2  Mathematical Statistics
Numerical data indexing:Size 3.50e-02m to 4.90e-02m, Time 2.14e+02s, Time 3.02e+02s, Velocity 1.00e-03m/s to 1.80e-02m/s, Velocity 1.80e-02m/s to 2.68e-01m/s
DOI:10.11975/j.issn.1002-6819.2017.10.010

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 20>

Accession number:20173304051893
Title:Unloading film process analysis and high-speed photography experiment of pole-tooth residual plastic film collector
Authors:Xie, Jianhua (1); Chen, Xuegeng (2); Sun, Chaowei (1) 
Author affiliation:(1) Department of Mechanical and Traffic, Xinjiang Agricultural University, Urumqi; 830052, China; (2) Xinjiang Academy of Agricultural Reclamation, Shihezi; 832000, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:17-24
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to solve the problem of "white pollution" caused by the residual plastic film, researchers has carried out a lot of researches on residual film recovery technology and produce a variety of residual film recycling equipments. Lots of residual plastic film collectors have been designed to address "how to pick up" in recent years, however, the problem of "how to unload" is often overlooked. This study was to investigate the uploading process of a pole-tooth residual plastic film collector that was designed to efficiently collect and unload residual plastic film. Based on the MB (Majumdar-Bhushan) contact fractal theory, the relationship between the contact load and the deformation during the contact between the unloading blade and the rod was obtained, and the relationship between the material and the motion characteristics of the dynamic contact load was also obtained by the dynamic contact analysis. The contacting payload and contacting deformation and dynamic influencing factors between picking-up pole-tooth and unloading film scraper in the process of film uploading were analyzed and simulated using a finite-element analysis software, ANSYS. A high-speed camera was used to track the trajectory of the picking-up pole-tooth, and the maximum deformation of picking-up pole-tooth and unloading film scraper front end was observed during the process of film unloading. The resulted showed that, to satisfy reliable unloading films, the maximum deformation of picking-up pole-tooth and unloading film scraper front end were 15.741 and 49.733 mm, respectively when the rotation speed of the picking-up film mechanism was 36 r/min. The pole-tooth plastic film residue collector could reach the higher production efficiency and ensure unloading film reliably when the speed of the machine was 0.85 m/s, and the speed ratio of machine to pole-tooth was 1.5, the pole-tooth residual film recovery machine could ensure reliable unloading of film in the case of high production efficiency. When the speed of the machine was 0.60 m/s, and the speed ratio of machine to pole-tooth was 1.0, because the speed of picking-up film mechanism was low, the film picked up by pole-tooth could be slipped off in the process of moving up. When the speed of the machine was 1.20 m/s, and the speed ratio of machine to pole-tooth was 1.5, the rotation speed of the picking-up film mechanism and unloading film mechanism were improved, and the working efficiency of the machine was improved. However, the contacting time of the film and the picking-up rod got shorter, which was harmful to the unloading and collection of the residual film. Through the finite element simulation and high-speed camera test of the unloading process, the contact deformation of the rod-splicing tooth and the unloading mechanism was observed, and the conditions of reliable unloading of the rod-type residual film recovery machine were analyzed, and the optimization of the equipment was provided, the experimental result was consistent with the simulation result. The results can provide the support for motion parameter optimization of picking-up and uploading residual film mechanisms in design of a pole-tooth residual film collector. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:High speed photography
Controlled terms:Cameras - Collector efficiency - Deformation - Dynamics - Efficiency - Films - Finite element method - High speed cameras - Image analysis - Photography  - Plastic films - Poles - Recovery - Rolling resistance - Rotation - Speed - Tools - Unloading
Uncontrolled terms:Contact analysis - Finite element analysis software - Finite element simulations - Motion characteristics - Picking up - Plastic film residues - Production efficiency - Residual plastic film collector
Classification code:408.2  Structural Members and Shapes - 691.2  Materials Handling Methods - 702.3  Solar Cells - 742.1  Photography - 742.2  Photographic Equipment - 746  Imaging Techniques - 817.1  Polymer Products - 818.5  Rubber Products - 913.1  Production Engineering - 921.6  Numerical Methods - 931.1  Mechanics
Numerical data indexing:Rotational_Speed 3.60e+01RPM, Size 1.57e-02m, Size 4.97e-02m, Velocity 1.20e+00m/s, Velocity 6.00e-01m/s, Velocity 8.50e-01m/s
DOI:10.11975/j.issn.1002-6819.2017.10.003

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 21>

Accession number:20173304051920
Title:Blind image denoising of microscopic slices image of Caragana stenophylla Pojark based on noise type and intensity estimation
Authors:Wang, Haichao (1); Wang, Chunguang (1); Zong, Zheying (1); Yin, Xiaofei (1); Zhang, Wenxia (1); Wang, Xiaorong (1); Zhang, Haijun (1); Li, Jing (1); Liu, Tao (1) 
Author affiliation:(1) College of Mechanical and Electrical Engineering, Inner Mongolia Agricultural University, Hohhot; 010018, China 
Corresponding author:Wang, Chunguang(jdwcg@imau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:229-238
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The microscopic images from leaf slices of Caragana stenophylla Pojark are inevitably corrupted by noise in obtaining, which will have a negative effect on its subsequent processes. The unpitched sound is usually treated as an additive Gaussian sound in order to denoise the natural images. It has not yet been known whether the unpitched sound and the additive Gaussian sound display the same distribution. The choice of the unpitched sound model will determine the estimation on its noise level and its subsequent choice of the denoising algorithm. BM3D (block-matching and three-dimensional filtering) is universally regarded as the best denoising algorithm, since it keeps the maximum information about texture, border, and other details of the image while denoising effectively. But the speed of BM3D is limited owing to too much calculation and its practical use is also limited because it needs the noise variation as a pretested input. SVD (singular valuable decomposition) is one of the best denoising algorithms but the noise of the image and its information can not be completely separated. The type of image, the level of the noise, and the change of color all affect the validity of the algorithm. This paper proposed a process, involving the estimation on the image type, the noise level and the algorithm of denoising, to solve the problems mentioned above and to denoise the microscopic images from leaf slices of Caragana stenophylla Pojark. The noise type was recognized as Gaussian noise by the rebuilding and fitting of the smooth histogram domain. The values, abstracted from the smooth histogram domain of 15 randomly selected microscopic images from leaf slices of Caragana stenophylla Pojark, were fitted with the Gaussian function, with the R2 value of 0.996 and the RMSE (root mean squared error) value of 0.144 6. And then the standard deviation of the noise was estimated via the estimation on noise level with the help of SVD domain image block. In the algorithm estimation, an initial estimative value was obtained from the SVD domain image block with the smallest entropy, and a more accurate value was got from its subsequent self-adapting correcting of the algorithm values. A two-step simulation experiment proved that this algorithm was much better in speed and accuracy in denoising than the other two estimation algorithms. When the standard deviation of noise was lower than 10, the proposed algorithm had the best accuracy; when the standard deviation of noise was higher than 10, this algorithm had the same accuracy with the estimation method of sliced image noise level, but had a better accuracy than SVD. This paper got a standard deviation of the image noise of between 2.5 and 4.0 for its estimation on the microscopic images from leaf slices of Caragana stenophylla Pojark. The image was denoised via GMF-BM3D, a joint algorithm by GMF (geometric mean filtering) and BM3D. GMF was used to denoise the background of images and then BM3D was applied to denoise the target area. Experiments proved the algorithm introduced in this paper was good at denoising and remaining detailed information of the image, such as border and texture, with a much greater speed. The average value of the BRISQUE (blind/referenceless image spatial quality evaluator) of the processed image was 10, equivalent to half of that of the original image. The algorithm also had an equivalent effect in denoising with the traditional BM3D, but eight ninths of time was saved. It was better than WT (wavelet threshold) denoising in BRISQUE, which was lowered by about 4. Therefore, the algorithm in this paper accurately denoises the microscopic images from leaf slices of Caragana stenophylla Pojark and provides a reliable technical support for its subsequent image processing. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Image denoising
Controlled terms:Acoustic noise - Blind equalization - Estimation - Gaussian distribution - Gaussian noise (electronic) - Graphic methods - Image processing - Image texture - Information filtering - Mean square error  - Statistics
Uncontrolled terms:Caragana stenophylla Pojark - De-noising algorithm - Estimation algorithm - Gaussian functions - Intensity estimation - Noise levels - Root mean squared errors - Slices images
Classification code:723.2  Data Processing and Image Processing - 751.4  Acoustic Noise - 903.1  Information Sources and Analysis - 921  Mathematics - 922.2  Mathematical Statistics
DOI:10.11975/j.issn.1002-6819.2017.10.030

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 22>

Accession number:20173304051905
Title:Prediction of total power growth of agricultural machinery based on empirical mode decomposition and BP neural network
Authors:Wang, Jinfeng (1); Yan, Dongwei (1); Ju, Jinyan (2); Wang, Jinwu (1) 
Author affiliation:(1) College of Engineering, Northeast Agricultural University, Harbin; 150030, China; (2) College of Mechanical Engineering, Heilongjiang University of Science and Technology, Harbin; 150022, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:116-122
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The traditional time series prediction models and multi-factor linear regression prediction models for total power of agricultural machinery are difficult to meet the actual analysis and forecasting demand. The total power growth of agricultural machinery and its influencing factors have strong correlation and obvious nonlinear fluctuation characteristics in various time scales. Taking the time series data of the total power growth of agricultural machinery and its influencing factors from 1986 to 2013 as the research objects, the prediction model for the total power growth of agricultural machinery was proposed to improve the accuracy and reliability of prediction results based on empirical mode decomposition (EMD) and BP (back propagation) neural network. The total power growth of agricultural machinery was affected by many factors such as government macro policy, farmers' income growth, production scale expanding, production capacity improving, and so on. In order to determine the main influencing factors, the principal component analysis method was adopted to analyze the main contribution factors, and then the correlation analysis method was used to analyze the correlations between factors. The less affected factors were eliminated, and ultimately, planting area per labor, government finance investment, per capita net income of farmers, fuel price index and the number of first industry practitioners were determined as the main influencing factors, which were used to forecast the total power growth of agricultural machinery. The EMD method was adopted to decompose the total power growth of agricultural machinery and its main influencing factors from 1986 to 2013 in multi-time scale, the intrinsic mode functions (IMFs) with different time scales and the trend items were obtained, and then the nonlinear relationships between each IMF component and trend item of the total power growth of agricultural machinery and volatile component of influencing factors were established using BP network. At last, the results were reconstructed to forecast the total power growth of agricultural machinery. In order to evaluate the accuracy of developed EMD-BP model, the comparative models of multiple linear regression (MLR), support vector machine (SVM) model and BP neural network were developed. The prediction results of EMD-BP network, MLR, SVM model and BP neural network were analyzed. The average relative error of EMD-BP model fitting and prediction was 0.99% and 1.29% respectively, the relevant decision coefficient was 0.999, the standard error was 316.35 MW, and the evaluation grade of the model was good, and thus the accuracy evaluation indicators of EMD-BP network were better than other methods and had high precision and reliability. The results show that the EMD method can clearly express the volatility of original time series in different time scales, which can solve the prediction problem of multi-time scale sequence. The BP neural network is a kind of effective prediction method for the total power growth of agricultural machinery with nonlinear fluctuation. The developed EMD-BP neural network can determine the fluctuation relationships between the total power of agricultural machinery and its main influencing factors in each time scale, which can effectively solve the forecast problem of the total power growth of agricultural machinery and improve the accuracy of predicted results. The EMD-BP neural network offers a new method for quantitatively predicting the total power growth of agricultural machinery, and provides effective references for developing agricultural mechanization development plan and publishing relevant policy. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Agricultural machinery
Controlled terms:Agriculture - Backpropagation - Factor analysis - Forecasting - Investments - Linear regression - Models - Neural networks - Nonlinear analysis - Principal component analysis  - Signal processing - Support vector machines - Time measurement - Time series - Time series analysis
Uncontrolled terms:Agricultural mechanization - BP (back propagation) neural network - BP neural networks - Empirical Mode Decomposition - Fluctuation characteristics - Multiple linear regressions - Principal component analysis method - Total power
Classification code:716.1  Information Theory and Signal Processing - 723  Computer Software, Data Handling and Applications - 723.4  Artificial Intelligence - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 821.1  Agricultural Machinery and Equipment - 922.2  Mathematical Statistics - 943.3  Special Purpose Instruments
Numerical data indexing:Percentage 1.29e+00%, Percentage 9.90e-01%, Power 3.16e+08W
DOI:10.11975/j.issn.1002-6819.2017.10.015

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 23>

Accession number:20173304051899
Title:Mobile robot localization algorithm by combining visual odometry with natural landmarks
Authors:Wang, Zhi (1); Zhu, Shiqiang (1); Li, Yuehua (1); Zhang, Xuequn (1) 
Author affiliation:(1) State Key Laboratory of Fluid Power and Mechatronic Systems, Zhejiang University, Hangzhou; 310027, China 
Corresponding author:Zhu, Shiqiang(sqzhu@zju.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:70-77
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Localization is crucial for the mobile robot system. Various localization methods have been proposed, such as light detection and ranging (LIDAR), ultrasonic method, WIFI, ultra wideband (UWB), vision odometry, and so on. The vision-based localization method has been intensively researched recently. Many researchers focus on the visual odometry, such as the monocular odometry and the stereo odometry. But the most obvious weakness of the visual odometry is the cumulative error, which will increase as the increasing of the displacement. To solve this problem, the artificial landmarks are adopted for absolute localization. But it needs previous setting and calibration. According to these observations, a mobile robot localization algorithm based on monocular vision and natural landmarks was proposed. The ordinary camera and omnidirectional camera are adopted in this method. The ordinary camera is used to extract the features from the ceiling for visual odometry, and the omnidirectional camera is used to extract the features from the environment and ceiling; then a natural landmark base is built using the Harris-SIFT (Scale-invariant feature transform) method. If there are not natural landmarks, the localization is implemented according to the change of the feature point between 2 neighboring images. If there exist natural landmarks, they will be used to localize the robot. During the visual odometry process, the feature point is extracted from the ceiling image and then tracked the feature point through the whole trajectory. The rotation angle and translation matrix can be determined by the coordinates of the feature point in the image and the world coordinate system. If the feature point is far away from the image center, it should be reselected so that it is close to the image center. The local search method for feature point is adopted to accelerate the localization. The search of feature point is only implemented near the feature point in the last frame. If there exist natural landmarks, the orientation filter is used to estimate the orientation angles. In this filter, the indirect Kalman filter is adopted, which uses the orientation error space as the state of the filter. Moreover, the orientation filter fuses the data of visual odometry and the inertial measurement unit to calculate the orientation angles. Then, the Harris-SIFT algorithm is used to determine the feature point for localization. To fully remove the outliers, the cluster analysis is implemented to cluster the matching points. And then the optimal matching is used to determine the feature point. The localization is implemented considering the orientation angles and the feature point obtained above. This algorithm has both of the advantages of the real-time performance of relative localization and the accuracy of absolute localization. The indoor experiment was implemented. The average errors of the proposed method in x axis and y axis were 38.66 and 31.54 mm, respectively. Compared with the visual odometry, the errors were decreased by 32.53% and 68.68%, respectively. As to the computational efficiency, the runtime of the localization based on only natural landmarks was almost 6 times higher than that of the proposed method. Thus, the proposed method can achieve real-time performance. The indoor experimental results demonstrate that compared with the visual odometry, the proposed method is much more accurate, and has a better extendibility. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Indoor positioning systems
Controlled terms:Cameras - Ceilings - Cluster analysis - Computational efficiency - Computer vision - Errors - Image processing - Kalman filters - Mobile robots - Optical radar  - Robot applications - Robots - Stereo image processing - Ultra-wideband (UWB) - Ultrasonic applications - Units of measurement - Video cameras - Vision
Uncontrolled terms:Inertial measurement unit - Light detection and ranging - Mobile robot localization - Natural landmark - Scale invariant feature transforms - Vision based localization - Visual localization - World coordinate systems
Classification code:402  Buildings and Towers - 716.2  Radar Systems and Equipment - 716.3  Radio Systems and Equipment - 723  Computer Software, Data Handling and Applications - 731.5  Robotics - 731.6  Robot Applications - 742.2  Photographic Equipment - 753.3  Ultrasonic Applications - 902.2  Codes and Standards
Numerical data indexing:Percentage 3.25e+01%, Percentage 6.87e+01%, Size 3.15e-02m, Size 3.87e-02m
DOI:10.11975/j.issn.1002-6819.2017.10.009

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 24>

Accession number:20173304051896
Title:Attitude coordination control and accurately sawing-positioning of high-branch pruning machine
Authors:Li, Yang (1, 2); Du, Shuai (1); Chen, Baolin (1); Fu, Guanghua (1); Yuan, Jin (1, 2) 
Author affiliation:(1) College of Mechanical &amp; Electronic Engineering, Shandong Agricultural University, Tai'an; 271018, China; (2) Shandong Provincial Key Laboratory of Horticultural Machinery and Equipment, Tai'an; 271018, China 
Corresponding author:Yuan, Jin(jyuan@sdau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:40-48
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Tree pruning can promote the accumulation of photosynthetic products, reduce the forest stand density, improve the utilization performance of air and light for stands, and promote the growth of trees, which is an important task for the forest maintenance. In recent years, the domestic pruning machinery research has made some achievements. However, the domestic and international high-altitude pruning machinery is still in its infancy at present. The operating height is generally less than 8 m, and the machine is difficult to improve the work efficiency of pruning high branches. Against to the current prevalence of pruning machinery at home and abroad, i.e. the high-degree lack of mechanical flexibility, which results in high labor intensity for operator and high operational risk, the mechanical structure of pruning high branches machine was designed (in theory tall tree pruning work within 15 m can be realized). By observing the relative position of the saw head and the branches, the operator can flexibly control the 3-arm coordinated movement to perform sawing and positioning using the human machine interface on the industrial plate pc (personal computer). In order to improve the ease use of the machine further, the wireless camera was designed to fix in front of the saw head to assist the ground operator to observe the high-altitude saw head and branch distance. The arm system is composed of 3 arms, which is fixed on the turntable of a lifting platform. Each arm is driven by one joint to rotate around the axis, and the pruning saw is fixed to the end of the third arm. The whole pruning height can reach 15 m, the pruning operating radius is up to 6 m, and the maximum pruning diameter can reach 10 cm, which meet the requirements of high altitude pruning operations. In this paper, the working principle of high-altitude pruning machine was described, and the pruning positioning was implemented by forward and inverse kinematics analysis of the manipulators. According to the mechanical structure of the pruning machine, the structural feature of the manipulator system was analyzed, and the mapping relation between the joint angle and the telescopic amount of the electric cylinder was obtained. The high-altitude pruning machine control system and integrated cutting positioning method were researched and developed. The control system of high-branch pruning machine based on touch-screen industrial flat plate was designed, and the control application based on Windows and MFC (Microsoft Foundation Classes) was adopted to realize the independent action or coordinated control of the 3 manipulators, the platform control, and the turntable control, which realized the positioning method of pruning machine. The open-area prototype pruning test was implemented, and the controller and control method were applied to the prototype test. In addition, through the prototype test, the error measurement and the error compensation in the open area were performed. The test results showed that the control system and the control method designed in this paper could realize the precise positioning of end-point pruning saw in the 2 coordinate axes of the space, of which the standard deviation was less than 5 mm. With the 15 m operating height, and the 6 m operating radius range of the pruning machine, it obtained a higher accuracy. So, it can meet the design requirements, and achieve precise positioning and pruning operations. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Altitude control
Controlled terms:Control systems - Control theory - Error compensation - Fixed platforms - Forestry - Human computer interaction - Industrial manipulators - Inverse kinematics - Inverse problems - Kinematics  - Machinery - Manipulators - Personal computers - Plates (structural components) - Position control - Sawing - Touch screens
Uncontrolled terms:Branch pruning - Co-ordinated control - Forward and inverse kinematics - Human Machine Interface - Machine control systems - Mechanical flexibility - Microsoft foundation class - Pruning positioning
Classification code:408.2  Structural Members and Shapes - 511.2  Oil Field Equipment - 722.2  Computer Peripheral Equipment - 722.4  Digital Computers and Systems - 731  Automatic Control Principles and Applications - 931.1  Mechanics
Numerical data indexing:Size 1.00e-01m, Size 1.50e+01m, Size 5.00e-03m, Size 6.00e+00m, Size 8.00e+00m
DOI:10.11975/j.issn.1002-6819.2017.10.006

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 25>

Accession number:20173304051929
Title:Application of ozone concentration precise control fumigation device improving quality of raspberries during cold storage
Authors:Zhang, Na (1); Li, Kunlun (1); Wang, Wensheng (1); Yan, Ruixiang (1) 
Author affiliation:(1) Tianjin Key Laboratory of Postharvest Physiology and Storage of Agricultural Products, National Engineering and Technology Research Center for Preservation of Agricultural Products, Tianjin; 300384, China 
Corresponding author:Yan, Ruixiang(yrxan@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:295-301
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to define the effect of precise control of ozone treatment on the quality of raspberries during cold storage, and promote the application of ozone precision control device in the fruits and vegetables postharvest fresh-keeping, the fresh raspberry (variety: Heritage) was processed with short-term fumigation (4 &#8451;, 1 h, relative humidity of 95%) using the precise ozone refrigerated fumigation device, which was developed by National Engineering and Technology Research Center for Preservation of Agricultural Products. The ozone concentration was set as 0.21, 0.54 and 1.07 mg/L, and the fumigated raspberries were placed in cold store (0 &#8451;). The ozone fumigation device was tested, and the effects of different concentrations of ozone fumigation treatment on raspberry postharvest storage quality were analyzed. Results showed that using a two-wire ozone transducer installed inside refrigerated cabinet, and through the ozone sensor, the device turned the ozone concentration of refrigerated cabinet into current output to the intelligent measurement and control device, which was then compared with the parameters set on intelligent measurement and control instrument. Thus by relay signal to control the switch of ozone generator, the precise control of ozone concentration was realized. The device could set the concentration in a relatively short time, and accurately control the ozone concentration. The ozone concentrations of 0.21, 0.54 and 1.07 mg/L were respectively acquired after 96, 168, and 240 s since they were set, and the device control precision was 0.05 mg/L. The ozone fumigation treatment could inhibit significantly microorganism of raspberries to flourish (P&lt;0.05), and the total number of colony in raspberries could be reduced by 1.62 orders of magnitude with 1.07 mg/L treatment. The greater the ozone concentration, the smaller the number of colonies, and the ozone concentration and microbial quantity had concentration- response relationship. The color, flavor, hardness, and rotting performance of raspberry with different treatment were good on the 5th day. Raspberry with 0.54 mg/L ozone treatment still had bright red color, fruit tissue without loss, good hardness, and thicker fragrance, but the color, fragrance and hardness of raspberry in control group were poor, and partially rotting of raspberry surface appeared on the 15th day. The raspberry in control group and 1.07 mg/L treatment group had large decay, and the raspberries after 0.54 mg/L ozone fumigation processing still had good performance in color, fragrance and hardness, but individual fruits rotted; there was significant difference between 0.54 and 0.21 mg/L treatment group (P&lt;0.05), and they had extremely significant difference with the control group and 1.07 mg/L treatment group (P&lt;0.01) on the 25th day. For the raspberries treated with 0.21, and 0.54 mg/L ozone fumigation, the degradation of vitamin C, titratable acid, hardness and soluble solids content could be delayed effectively. The 0.54 mg/L ozone fumigation group had the best effect among the treatments. When the ozone concentration was higher than 1.07 mg/L, slight damage appeared on the surface of the raspberry, which promoted the decay of postharvest raspberry, and lowered the nutritional quality, and was not conducive to raspberries storage. In conclusion, precise control of ozone concentration has the potential for making clear the effect of ozone treatment, and controlling the postharvest quality of fruits and vegetables. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Quality control
Controlled terms:Agricultural products - Cold storage - Color - Energy storage - Fruits - Fumigation - Hardness - Humidity control - Information dissemination - Ozone  - Precision engineering - Speed control - Vegetables
Uncontrolled terms:Engineering and technology - Fruits and vegetables - Fumigate - Intelligent measurement - Intelligent measurement and control devices - Nutritional qualities - Raspberry - Soluble solids content
Classification code:525.7  Energy Storage - 644.3  Refrigeration Equipment and Components - 731.3  Specific Variables Control - 741.1  Light/Optics - 804  Chemical Products Generally - 821.4  Agricultural Products - 903.2  Information Dissemination - 913.3  Quality Assurance and Control - 951  Materials Science
Numerical data indexing:Time 3.60e+03s, Mass_Density 1.07e-03kg/m3, Mass_Density 5.00e-05kg/m3, Mass_Density 5.40e-04kg/m3 to 2.10e-04kg/m3, Mass_Density 5.40e-04kg/m3, Percentage 9.50e+01%, Time 2.40e+02s
DOI:10.11975/j.issn.1002-6819.2017.10.039

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 26>

Accession number:20173304051931
Title:Oil absorption rule of fried potato chips during different frying time
Authors:Li, Jinwei (1); Wang, Min (2); Zhang, Tingting (1); Liu, Yuanfa (1); Fan, Liuping (1); Ding, Shaodong (3) 
Author affiliation:(1) Food Science and Technology, Jiangnan University, Wuxi; 214122, China; (2) Shanghai Reli Technology Group Co., Ltd., Shanghai; 200125, China; (3) State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi; 214122, China 
Corresponding author:Fan, Liuping(fanliuping@jiangnan.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:310-314
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to characterize the oil absorption behavior of potato chips during the different frying time, the soxhlet extraction, dye method, confocal laser scanning microscopy and low field nuclear magnetic resonance imaging were combined to analyze and explain the oil absorption behavior of potato chips in this paper. When the frying temperature was 180&#8451; and the ratio of oil to material was 10:1, the changing rules of oil content, oil type and oil distribution of potato chips during the different frying time were obtained. In addition, the porosity characteristics of potato chips were also used to explain the oil absorption behavior during frying. The results showed that frying time (0-12 min) significantly affected the content of total oil, surface oil, structural oil and surface penetrated oil of potato chips at the frying temperature of 180&#8451; and the ratio of oil to material of 10:1 (P&lt;0.05). The total oil content of potato chips increased with the increase of frying time. When the frying time reached 10 min, the total oil content of potato chips was 47.09%, and then it gradually tended to be stable. The surface oil content of potato chips was the lowest, which was about 1.30%-2.06%. The structural oil content of potato chips increased with the increase of frying time, however the PSO content of potato chips decreased when the frying time exceeded 6 min. The confocal laser scanning microscopy showed that during the frying process, the red region of potato chips enlarged with the increase of frying time, which meant the increase of the oil content of potato chips. The oil was permeated from the surface of the potato slice to the interior and located on cell walls, which followed the cell shapes and filled the intercellular spaces. When the frying time was 0-8 min, the pore volume and porosity increased with the increase of frying time, and the oil content of potato chips was also increased. Overall, this study has an important significance for the characterization of oil absorption behavior of potato chips during the frying process. Besides, it provides reliable data and effective means for the development of potato chips with the lower oil content. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Oils and fats
Controlled terms:Characterization - Confocal microscopy - Food processing - Laser applications - Magnetic resonance imaging - Microstructure - Porosity - Surface analysis
Uncontrolled terms:Confocal laser scanning microscopy - Frying - Frying temperature - Intercellular spaces - Low field nuclear magnetic resonance - Oil contents - Pore character - Soxhlet extraction
Classification code:744.9  Laser Applications - 746  Imaging Techniques - 804.1  Organic Compounds - 822.2  Food Processing Operations - 931.2  Physical Properties of Gases, Liquids and Solids - 951  Materials Science
Numerical data indexing:Percentage 1.30e+00% to 2.06e+00%, Percentage 4.71e+01%, Time 0.00e+00s to 4.80e+02s, Time 0.00e+00s to 7.20e+02s, Time 3.60e+02s, Time 6.00e+02s
DOI:10.11975/j.issn.1002-6819.2017.10.041

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 27>

Accession number:20173304051916
Title:Experimental study on root-soil friction mechanical of Caragana korshinskii Kom. mechanism in loess area
Authors:Liu, Yabin (1, 2); Yu, Dongmei (1); Fu, Jiangtao (1, 2); Hu, Xiasong (1, 3); Qi, Zhaoxin (1, 2); Zhu, Haili (1, 2); Li, Shuxia (1, 2) 
Author affiliation:(1) Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Key Laboratory of Salt Lake Geology and Environment of the Qinghai Province, Xining; 810008, China; (2) University of Chinese Academy of Sciences, Beijing; 100049, China; (3) Department of Geological Engineering, Qinghai University, Xining; 810016, China 
Corresponding author:Hu, Xiasong(huxiasong@tsinghua.org.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:198-205
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:To systemically research the shrub roots pull-out friction mechanical mechanism, a shrub Caragana korshinskii (C. korshinskii) Kom. with a growth period of 2 years, which was planted in the self-established testing area in the loess area of the Xining Basin, was selected as the research object. Eighteen C. korshinskii roots samples were selected in the pull-out friction test, and four of them were tested under the condition without lateral roots, which was aimed to evaluate the effect of the lateral roots in pull-out process. The relationships between the maximum root-soil friction and 5 morphology indices of roots (total root surface area, total root volume, total root length, total root dry weight, and lateral root number) were analyzed via regression analysis. Meanwhile, the static friction coefficient between taproot of C. korshinskii and soil was calculated through pull-out friction test under the condition without lateral roots. The test results were as follows: The pull-out process of roots of C. korshinski could be divided into the stage of static friction and the stage of dynamic friction, which were reflected in the relationship curve of root-soil friction and displacement, and when the lateral roots were not cut, a nonlinear increase phase of root-soil friction existed in the relationship curve of root-soil friction and displacement; the major effect of taproot was to provide static friction between soil and roots, and the effect of the lateral roots was to enhance the maximum root-soil static friction, the maximum root-soil friction, and the root displacement corresponding to the maximum root-soil friction to a greater extent. Under the condition without lateral roots, the maximum root-soil static friction of 4 roots samples (1#, 2#, 3# and 4#) decreased by 16.7%, 33.3%, 16.7% and 20.0% respectively, the maximum root-soil friction decreased by 44.0%, 50.0%, 37.5% and 42.9%, respectively, and the root displacement corresponding to the maximum root-soil friction reduced by 88.9%, 88.2%, 85.3% and 84.6%, respectively. The mechanism of lateral roots to improve the capability of C. korshinskii roots to resist uprooting could be attributed to the shear type friction and debonded friction produced by lateral roots. The phenomenon that the lateral roots were gathered around the taproot at the end of the pull-out friction test showed that the above analysis was reasonable to some extent; The maximum root-soil friction tended to increase with the increasing of total root surface area, total root volume, total root length, total root dry weight and lateral root number, and a power function relationship was established between these 5 root morphology indices and the maximum root-soil friction. The correlation analysis showed that total root surface area was the morphology index which had the most significant degree of correlation with the maximum root-soil friction (the multiple correlation coefficient was 0.9562); the static friction coefficient between taproot of C. korshinskii and soil was 0.7389&plusmn;0.04, and it was significantly greater than that the corresponding static coefficient of soil without roots, 0.5040&plusmn;0.03, which suggested the friction value of C. korshinskii root-soil interface and its ability to resist deformation were greater than the soil without roots. The research is useful to further investigate pull-out friction mechanical mechanism for shrub roots, and meanwhile this conclusion has a theoretical significance and practical value in preventing soil erosion, shallow landslide and other geological hazards in testing area. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Soil testing
Controlled terms:Forestry - Friction - Mechanical properties - Morphology - Plants (botany) - Regression analysis - Sediments - Soils - Stiction - Tribology
Uncontrolled terms:Caragana korshinskii kom - Loess area - Pull out friction - Root morphology - Soil friction - Static friction coefficient
Classification code:483  Soil Mechanics and Foundations - 483.1  Soils and Soil Mechanics - 922.2  Mathematical Statistics - 931  Classical Physics; Quantum Theory; Relativity - 951  Materials Science
Numerical data indexing:Age 2.00e+00yr, Percentage 1.67e+01%, Percentage 2.00e+01%, Percentage 3.33e+01%, Percentage 3.75e+01%, Percentage 4.29e+01%, Percentage 4.40e+01%, Percentage 5.00e+01%, Percentage 8.46e+01%, Percentage 8.53e+01%, Percentage 8.82e+01%, Percentage 8.89e+01%
DOI:10.11975/j.issn.1002-6819.2017.10.026

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 28>

Accession number:20173304051895
Title:Design and experiment on blade shaft of 1KS60-35X type orchard double-helix trenching and fertilization machine
Authors:Xiao, Hongru (1); Zhao, Ying (1); Ding, Wenqin (1); Mei, Song (1); Han, Yu (1); Zhang, Yuan (2); Yan, Huaijiang (2); Song, Zhiyu (1) 
Author affiliation:(1) Nanjing Research Institute for Agricultural Mechanization, Ministry of Agricultural, Nanjing; 210014, China; (2) Xuzhou Agricultural Machinery Technology Extending Stations, Xuzhou; 221006, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:32-39
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The traditional orchard fertilization scheme is the sequence of trenching, fertilization and covering soil. In the process of orchard planting and management, trenching deeply is a key link, which has a great impact on the yield of orchard as well as the sweetness and quality of the orchard fruit. However, at present, orchard trenching and fertilization machine has a series of problems, such as great cultivation resistance, high power consumption and uneven mixing fertilizer, and there is a great need to develop a new kind of fertilization machine. So a double-helix fertilization machine named 1KS60-35X was designed, which used the front axle to break the ground while used the rear axle to mix the soil and fertilizer. The resistance torque equation of the rotary shaft used for breaking and mixing the soil was established, which could be used to quantitatively analyze the effect of screw blade parameters on tillage resistance. Furthermore, on the basis of the research on the parametric equation of spiral cutting edge, as well as by means of experience and theory calculation, the helical blade parameters of ground soil fertilization shaft were determined. Then the 3D (three- dimensional) parametric models of the cutter shaft and the whole machine were established using Pro/E. On this foundation, the prototype of a double-helix fertilization machine was completed. Afterwards, a series of trenching and fertilization field experiments were carried out, and the results showed that the ditching depth of this machine could achieve from 472 to 510 mm, and meanwhile the average depth could reach 496 mm and the average soil pushing height could attain 120 mm. In addition, the planting depth stability coefficient could achieve 98.2% and the planting width consistency could reach 99.2%. The soil aggregate diameters were mostly between 3 and 6 mm; the soil aggregate diameter in the whole soil and 100 mm surface soil ranged from 5 to 40 mm, while those from the sampling results were 6.75 and 6.86 mm, respectively. So the qualified rates of broken soil were 98.7% and 97.9%, respectively. The situation of granular fertilizer accumulation occurred less by using this machine, the vertical and horizontal distances of the centers of gravities were 16.24 and 15.53 mm, respectively, and the fertilization performance of each soil layer was relatively stable. This new designed machine abandoned the traditional operation mode of first trenching, then fertilization, and then covering the soil, while adopted the new operation mode that trenching, fertilization and covering the soil were carried out at the same time. So the number of operations could be effectively reduced. Therefore, with this new machine, the fertilization can be uniform and reduce the waste of fertilizer. What's more, it can improve the soil structure and promote the root system of the fruit trees, which is beneficial to fruit growth. This new designed machine not only meets the agronomic requirements of orchard fertilization, but also provides a reference for the trenching and fertilization operation in mulberry field and tea garden. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:21
Main heading:Soils
Controlled terms:Aggregates - Agricultural machinery - Agriculture - Axles - Compressive strength - Cultivation - Cutting - Design - Experiments - Farms  - Fertilizers - Front axles - Fruits - Machine design - Mixing - Orchards - Trenching
Uncontrolled terms:3-D (three-dimensional) - Double helix - Granular fertilizers - High power consumption - New operation modes - Parametric equation - Stability coefficient - Theory calculation
Classification code:406  Highway Engineering - 483.1  Soils and Soil Mechanics - 601  Mechanical Design - 619.1  Pipe, Piping and Pipelines - 662.4  Automobile and Smaller Vehicle Components - 802.3  Chemical Operations - 804  Chemical Products Generally - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 901.3  Engineering Research
Numerical data indexing:Percentage 9.79e+01%, Percentage 9.82e+01%, Percentage 9.87e+01%, Percentage 9.92e+01%, Size 1.00e-01m, Size 1.20e-01m, Size 1.55e-02m, Size 1.62e-02m, Size 4.72e-01m to 5.10e-01m, Size 4.96e-01m, Size 5.00e-03m to 4.00e-02m, Size 6.75e-03m, Size 6.86e-03m
DOI:10.11975/j.issn.1002-6819.2017.10.005

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 29>

Accession number:20173304051898
Title:Research advance on vision system of apple picking robot
Authors:Wang, Dandan (1); Song, Huaibo (1); He, Dongjian (1) 
Author affiliation:(1) College of Mechanical and Electronic Engineering, Northwest A&amp;F University, Yangling; 712100, China 
Corresponding author:He, Dongjian(hdj168@nwsuaf.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:59-69
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Vision system is one of the most important parts of apple picking robot, which, to some extent, determines the quality and the speed of picking task implemented by apple picking robot. In this review, we enumerated the existing apple picking robots. Some information, such as type of visual sensors, hardware of vision system, success rate of harvesting and run time, was illustrated in details. Meanwhile, on the basis of discussing the vision system of apple picking robot, we focused on summarizing hardware structure of existing vision systems and apple image segmentation methods as well as apple recognition and localization methods applied in vision systems. The vision system of apple picking robot mainly includes machine vision system, laser vision system, three-dimensional vision system and vision system formed by machine vision and other vision system. And the machine vision system can be classified into 3 types according to the number of image sensors used, that is, monocular vision system, binocular vision system and multi vision system. The recognition and localization of apple target is the first step of the implementation of the picking task for picking robot. The currently used apple segmentation and recognition methods include threshold segmentation algorithm, chromatic aberration based algorithm, K-mean clustering algorithm, region growing algorithm, segmentation method combining 2 or more algorithms, and so on. There are 4 methods that are commonly used in the localization of apple target. They are the methods based on centroid, fitting circle, symmetry axes, and three-dimensional coordinates, respectively. In natural scene, the recognition and localization of apple target may be affected by many factors. Hence, recognition and localization of apple target under different conditions, such as color nonuniformity, different illumination, shadow on the surface, oscillation, overlapping and occlusion, was reviewed and analyzed. Among all these conditions, occlusion can be regarded as the most serious factor. The condition of occlusion can be roughly divided into 4 kinds, i.e. apple target blocked by other apple, by branches, by leaves and by branches, leaves and other apple simultaneously. As for apple targets blocked by branches, one apple may be separated by branches, thus causing that an apple may be recognized as several apples. For the apple targets blocked by leaves, the symmetry of apple can be utilized to localize apple targets. The apple targets blocked by other apple can be considered as overlapping. There are overlapped apples with series connection, parallel connection, and blend connection. Because of the complexity of overlapping, the recognition and localization of apple targets blocked by other apple target is a little more difficult. In addition, the detection of obstacles like tree trunk and branches in apple orchard is important for apple picking robots to avoid obstacles, and thus obstacles detection methods were summarized in this review. In the process of target recognition and localization, binocular vision technology was commonly used in vision system. The key point of binocular vision technology is stereo matching. Therefore, stereo matching was then reviewed, and the image matching methods in existence can generally be divided into 2 categories, i.e. region-based image matching method and feature-based image matching method. What's more, the problems exist in recognition and localization methods used in the vision system of apple picking robot, including accuracy, effectiveness, character of real-time and universal applicability, were analyzed. Further study will concentrate on optimizing the structure of vision system, optimizing the intelligent algorithms used in the vision system, improving the real-time capability, recognizing and locating apple targets when the apple targets and vision systems are influenced by oscillation, and improving cost performance. The paper has summarized and analyzed vision system of apple picking robot comprehensively, which can provide reference for future research. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:101
Main heading:Stereo image processing
Controlled terms:Aberrations - Binocular vision - Bins - Clustering algorithms - Computer vision - Electric connectors - Fruits - Hardware - Image matching - Image recognition  - Image segmentation - Machinery - Mechanization - Real time systems - Robots - Stereo vision
Uncontrolled terms:Apple - Binocular vision systems - Feature-based image matching - Fruit recognition - K-mean clustering algorithm - Target localization - Three dimensional coordinate - Vision systems
Classification code:601  Mechanical Design - 605  Small Tools and Hardware - 694.4  Storage - 704.1  Electric Components - 722.4  Digital Computers and Systems - 723.2  Data Processing and Image Processing - 731.5  Robotics - 741.2  Vision - 821.4  Agricultural Products - 903.1  Information Sources and Analysis
DOI:10.11975/j.issn.1002-6819.2017.10.008

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 30>

Accession number:20173304051923
Title:Seismic performance of wedge-shaped box joint of beam and box column in tourism greenhouse structures
Authors:Li, Xiaorun (1, 2); Song, Bo (1); Chen, Shuirong (2) 
Author affiliation:(1) School of Civil and Environmental Engineering, University of Science and Technology Beijing, Beijing; 100083, China; (2) Central Research Institute of Building and Construction, MCC group Co., LTD, Beijing; 100088, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:252-257
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to meet the requirement of the greenhouse structure construction, a wedge-shaped box joint connecting box column and H-shaped beam was proposed to overcome the inconvenient construction and poor seismic performance of the conventional joint in the H-shaped beam and box section column, such as the conventional outboard plate joint and the internal baffles joint. The finite element simulation analysis of the joints under cyclic loading was carried out by the finite element analysis software ANSYS. The seismic performance of the joint was analyzed and compared with the conventional outboard plate joint and the internal baffles joint. The influences of the flange and web thickness of the beam, and the thickness of the rectangular tube column on the seismic performance of the joint were discussed. The seismic performance of the wedge-shaped box joint was better than that of the outboard plate joint, so it could be applied to the actual engineering instead of the conventional outboard plate joint. The cumulative energy consumption was 25.40% higher than that of the outboard plate joint, and 20.46% lower than that of the internal baffles joint. The stiffness of the wedge-shaped box joint was larger than that of the outboard plate joint. The hysteretic curve of the joint was relatively full, which embodied the good seismic performance. The plastic hinge of the internal baffles joint appeared at about 200 mm outside the column edge. The plastic hinge of the wedge-shaped box joint and the outboard plate joint was about 450 and 500 mm outside the column edge, respectively. However, the region area in the wedge-shaped box joint was smaller than the other joints. The plastic hinge position of the wedge-shaped box joint moved to the middle of the span under cyclic loadings, which ensured the design concept of "strong column with weak beam, strong node with weak component". The thickness of the flange and web of the wedge-shaped box joint had a great influence on the seismic performance. In the case of no exceeding the thickness of the column, the initial stiffness, the yield load and the ultimate bearing capacity of the joint were obviously increased with the increasing of the thickness of the flange and web of the beam, which meant that the seismic performance of the joint was improved. At the same time the adverse consequence of strong beam would not be produced. The change rate of cross section width of wedge-shaped box had a great influence on the energy dissipating capacity of the joint. As the change rate of cross section width decreased from 1:2 to 1:5, the energy dissipating capacity of the joint and the stiffness after yielding increased. However, it was difficult to make the production and installation of the joint. In practical engineering, it was suggested the change rate of cross section width should equal 1:4. Therefore, the distribution of the stress in the wedge-shaped box joint was more reasonable. After solving the defects of the internal baffles joint, such as the inconvenience of the construction and pouring concrete, the bearing capacity and stiffness of the wedge-shaped box joint were improved, which were beneficial to the seismic resistance of a structure. The above results show that the wedge-shaped box joint has a good seismic performance and is more suitable for tourism greenhouse structures. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Finite element method
Controlled terms:Bearing capacity - Computer software - Concrete testing - Cyclic loads - Earthquake engineering - Energy utilization - Flanges - Greenhouses - Hysteresis - Models  - Plates (structural components) - Rigidity - Seismic waves - Seismology - Stiffness
Uncontrolled terms:Beam-column joints - Cumulative energy consumption - Finite element analysis software - Finite element simulations - Hysteresis curve - Practical engineering - Seismic behavior - Ultimate bearing capacity
Classification code:408.1  Structural Design, General - 408.2  Structural Members and Shapes - 412  Concrete - 484  Seismology - 484.1  Earthquake Measurements and Analysis - 525.3  Energy Utilization - 619.1.1  Pipe Accessories - 723  Computer Software, Data Handling and Applications - 821.6  Farm Buildings and Other Structures - 921.6  Numerical Methods - 951  Materials Science - 961  Systems Science
Numerical data indexing:Percentage 2.05e+01%, Percentage 2.54e+01%, Size 2.00e-01m, Size 4.50e-01m, Size 5.00e-01m
DOI:10.11975/j.issn.1002-6819.2017.10.033

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 31>

Accession number:20173304051901
Title:Design and prototype performance experiments of steering-by-wire hydraulic pressure system of tractor
Authors:Fang, Susu (1); Lu, Zhixiong (2); Wang, Zengcai (1); Diao, Xiuyong (2); Lu, Yang (2); Gong, Jiahui (2); Zhu, Chunying (2) 
Author affiliation:(1) Key Laboratory of High Efficiency Clean Machinery Manufacturing, College of Mechanical Engineering, Shandong University, Jinan; 250061, China; (2) College of Engineering Agricultural University, Nanjing; 210031, China 
Corresponding author:Lu, Zhixiong(luzx@njau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:86-93
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The tractor steering system is the key to ensure the safe and efficient operation of the driving mechanism, the traditional hydraulic steering system in the steering process is prone to heavy steering and even failure, and the performance is not ideal, so this paper put forward a new hydraulic steering-by-wire system, which combined hydraulic steering technology with the steering-by-wire technology. This system not only cancels the steering wheel and the mechanical connection between the hand wheel and the steering gear, but also simplifies the hydraulic oil circuit design between the steering gear and steering wheel. It makes steering flexible and convenient, and meanwhile the use of hydraulic system can ensure high power output. Agricultural vehicles need to drive on the highway when transferring in the different regions, and its center of gravity is generally higher, while its speed is lower compared with the passenger vehicle. Actually, the speed is high in their own condition, and the vehicle's lateral stability is poor. When the agricultural vehicle is in operation, the driver needs to steer the wheel frequently, but the design of the variable angle transmission ratio and variable force transmission ratio of hydraulic steering-by-wire system makes the vehicle handling stability improved, and can reduce the driver's labor intensity effectively. Compared with the traditional full hydraulic steering system, the new system can better promote the development of agricultural vehicles, and eventually make the unmanned autonomous operation agricultural vehicles come true. This paper introduced the overall design of the tractor's hydraulic steering-by-wire system, and all kinds of important parts were showed clearly by design chart: ECU (electronic control unit), circuit design, input signal, output signal, and so on. The system uses the classical PID (proportion, integral, derivative) to design the controller, and the whole system is a closed loop control system. Building model and simulation analysis were based on Simulink/Simhydraulic module of MATLAB software, and the modeling and the real vehicle modification for various parts were all based on the overall design principle of hydraulic steering-by-wire system. After the completion of the selection of parts, the tractor was modified. The key components of the new system and the design of the circuit and controller were described in detail, which were compared with the original structure of the steering system. Meanwhile, the energy saving of the new system was analyzed in this paper. Then the static and dynamic experiments with the prototype were finished. The static experiment was a random rotation experiment, the main purpose of which was to test how the new system was feasible, and ensure that the dynamic experiments could be carried out safely. Four dynamic experiments were snake-shaped experiment, lemniscate experiment, steady-state experiment, and angle transient response experiment, which were used to evaluate different vehicle performances. Every experiment tested the hydraulic steering system and hydraulic steering-by-wire system respectively, and the 2 systems' difference was evaluated in the performance of steering sensitivity, handling stability, and convenient operation. In the experiment process of 2 systems, 2 kinds of data should be obtained, i.e. the hand wheel angle data (the theoretical angle data) and the steering wheel angle data (the actual angle data). Two kinds of data were compared and analyzed, and the experimental results showed that the theoretical and actual angle curve of hydraulic steering-by-wire system fitted better, and the error was lower than the full hydraulic system. Although both of the 2 steering systems could complete the steering action, the difference of performances existed between the hydraulic system and hydraulic steering-by-wire system. Hydraulic steering-by-wire system is feasible, which makes the function innovation, structure innovation, and practice innovation. In function, it combines the advantages of steering-by-wire technology and hydraulic technology, so that the tractor steering performance gets a new upgrade. The system structure innovation is to use various types of sensors to complete the closed-loop control, use electromagnetism proportional servo valve to replace the full hydraulic steering gear, and use the PID to controller complete steering system control. Based on theory design, we modified the tractor, and performed a series of experiments with the tractor. The final experiments results showed that the hydraulic steering-by-wire system can achieve better steering function compared with the traditional full hydraulic steering system. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Automobile steering equipment
Controlled terms:Agriculture - Closed loop control systems - Computer software - Computer systems - Control systems - Controllers - Digital storage - Dynamics - Energy conservation - Hydraulic equipment  - Hydraulic fluids - Integrated circuit manufacture - MATLAB - Pneumatic control equipment - Proportional control systems - Steering - System stability - Tractors (agricultural) - Tractors (truck) - Vehicle performance  - Vehicle transmissions - Vehicles - Wheels - Wire
Uncontrolled terms:Agricultural vehicles - Autonomous operations - Ecus (electronic control unit) - Handling stabilities - Hydraulic pressure system - Mechanical connections - Performance experiment - Steering sensitivities
Classification code:525.2  Energy Conservation - 535.2  Metal Forming - 601.2  Machine Components - 602.2  Mechanical Transmissions - 632.2  Hydraulic Equipment and Machinery - 662.4  Automobile and Smaller Vehicle Components - 663.1  Heavy Duty Motor Vehicles - 714.2  Semiconductor Devices and Integrated Circuits - 722.1  Data Storage, Equipment and Techniques - 723  Computer Software, Data Handling and Applications - 731.1  Control Systems - 732.1  Control Equipment - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 921  Mathematics - 961  Systems Science
DOI:10.11975/j.issn.1002-6819.2017.10.011

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 32>

Accession number:20173304051912
Title:Ridge and furrow mulching improving soil water-temperature condition and increasing potato yield in dry-farming areas of south Ningxia
Authors:Li, Rong (1); Wang, Yanli (1); Wu, Pengnian (1); Sun, Ruiping (1); Qiu, Jiaxin (1); Su, Mei (1); Hou, Xianqing (1) 
Author affiliation:(1) School of Agriculture, Ningxia University, Yinchuan; 750021, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:168-175
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The plastic-covered ridge and furrow rainwater harvesting combined with mulching cultivation can influence soil water-temperature condition, promote crop growth and development, and increase water use efficiency and yield of crop. This study was investigate the effect of mulching in furrows with different materials and in ridges with plastic film on soil water-temperature condition, potato growth and yield in dry-farming areas of south Ningxia. A field experiment was conducted in 2015 at the Dryland Agricultural Research Station, Changcheng Village, Pengyang County, Ningxia, China (106&deg;45&prime;N, 35&deg;79&prime;E, 1800 m sea level) to determine the effect of different dual-mulching of ridge and furrow cultivation patterns on soil water, soil temperature, growth, yield and water use efficiency of potato. Different furrow treatments were mulched with plastic film (DD), maize straw (DJ), biodegradable film (DS), bast fiber film (DM), liquid film (DY). The treatment of ridge with plastic film and the furrow without mulching was used as the control (CK). The results showed that, the dual-mulching with ridge and furrow adjusted soil temperature, improved moisture availability in the furrow, and the DD and DJ treatments were the most significant. The DD treatment significantly (P&lt;0.05) increased the soil water storage by 4.6%-5.4% compared to CK in the early and middle growing stage of potato. The soil water storage with DJ treatment was the highest in the later growing stage of potato (P&lt;0.05). The DJ treatment had the highest soil water-holding effect compared with CK in whole growing stage of potato, and the average soil water storage under DJ was significantly (P&lt;0.05) higher by 8.4% compare with CK (P&lt;0.05). The DD treatment produced significantly higher soil temperatures (0-25 mm) than CK in the entire stage of potato, while the soil temperature with DJ treatment was significantly lower than CK (P&lt;0.05) in the middle and later growing stage of potato. The average topsoil temperature was significantly increased under DD by 1.2&#8451; (P&lt;0.05) when compared with CK in the whole growing season of potato, while the soil temperature under the DJ treatment was 1.6&#8451; (P&lt;0.05) lower than CK. The plant height and stem diameter with DD and DJ treatment was significantly (P&lt;0.05) higher than that of CK in the early growing stage of potato, while the DJ treatment produced the highest plant height and stem diameter (P&lt;0.05) compared to CK in the middle and later growing stage of potato. The above-ground biomass of the DJ treatment was the highest after 110 days of sowing (P&lt;0.05), followed by the DD treatment, while there was no difference in the above-ground biomass of potato between DY and CK (P&gt;0.05). Higher potato yield and water-use efficiency was found with DD, DJ, DS and DM treatments. The yield and water use efficiency of potato with DJ treatment were the highest (37 213.5 kg/hm²and 81.1 kg/(hm²&middot;mm)). Compared with CK, the potato yield with DD, DJ, DS and DM treatments was significantly (P&lt;0.05) increased by 34.3%, 56.1%, 8.6%, and 11.3%, meanwhile the water-use efficiency increased by 39.3%, 65.9%, 14.7%, and 14.3% (P&lt;0.05). In a word, when ridges were covered with common plastic film, the furrows were mulched with straw, the soil water and temperature conditions were improved and potato growth and development was promoted, and the potato yield and water use efficiency were increased. Therefore, we suggested that plastic film mulched ridges and straw mulched furrows should be popularized and applied in arid area of southern Ningxia. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:38
Main heading:Water treatment
Controlled terms:Biodegradable polymers - Crops - Cultivation - Ecology - Efficiency - Film growth - Food storage - Forestry - Liquid films - Moisture  - Plastic films - Sea level - Soil moisture - Soils - Storage (materials) - Straw - Temperature - Water supply
Uncontrolled terms:Agricultural research - Crop growth and development - Dry farming - Growth and development - Potato yield - Rain water harvesting - Ridge and furrow - Temperature conditions
Classification code:445.1  Water Treatment Techniques - 446.1  Water Supply Systems - 454.3  Ecology and Ecosystems - 471.1  Oceanography, General - 483.1  Soils and Soil Mechanics - 641.1  Thermodynamics - 694.4  Storage - 815.1  Polymeric Materials - 817.1  Polymer Products - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 913.1  Production Engineering
Numerical data indexing:Age 3.01e-01yr, Percentage 1.13e+01%, Percentage 1.47e+01%, Percentage 3.43e+01%, Percentage 3.93e+01%, Percentage 4.60e+00% to 5.40e+00%, Percentage 5.61e+01%, Percentage 6.59e+01%, Percentage 8.40e+00%, Percentage 8.60e+00%, Size 0.00e+00m to 2.50e-02m, Size 1.80e+03m
DOI:10.11975/j.issn.1002-6819.2017.10.022

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 33>

Accession number:20173304051919
Title:Dynamic simulation of growth process of winter wheat in main production areas of China based on WOFOST model
Authors:Huang, Jianxi (1); Jia, Shiling (1); Ma, Hongyuan (1); Hou, Yingyu (2); He, Liang (2) 
Author affiliation:(1) College of Information and Electrical Engineering, China Agricultural University, Beijing; 100083, China; (2) National Meteorological Center, Beijing; 100081, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:222-228
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Crop model calibration and parameterization are essential for model evaluation and agricultural application. It is important for model application to accurately estimate the values of crop model parameters and further improve the performance of model prediction. WOFOST (world food studies) is a well-known, widely applied simulation model to analyze quantitatively the growth and production of field crops, which was originally developed for crops in European countries. It is the base model for Monitoring Agricultural Resources (MARS) Crop Growth Monitoring System (CGMS) in operational use for yield estimation in European Union. Dynamic simulation of WOFOST model in large regional scale is an important basis for regional crop modeling. In this study, we selected the main winter wheat production areas of China as the study area, and the data from 174 agricultural meteorological stations from 2011 to 2014 were used to calibrate several key WOFOST input parameters, especially 2 parameters related with variety, namely the effective accumulated temperature from emergence to flowering (TSUM1) and the effective accumulated temperature from flowering to maturity (TSUM2). On the basis of the zoning of the main winter wheat production areas, we used the meteorological data from 2012 to 2015 to drive the WOFOST model at a single-point scale, to simulate the winter wheat growth and dynamic development. The simulated phenology, LAI (leaf area index) and yield at the station level were evaluated with the field measured data. Results showed that the NRMSE (normalized root mean square error) of LAI ranged from 50% to 63%. The NRMSE of simulated days was 4%-7% from emergence to anthesis period and 8%-12% from anthesis to maturity period, and then CV (coefficient of variation) of the phenology was between 14% and 20%, which meant significant spatial variability. We simulated the yield respectively in irrigated area and rainfed area. And the NRMSE of simulated yield in irrigated area ranged from 11% to 23%, while the NRMSE of simulated yield in rain-fed area ranged from 22% and 28%, and the CV ranged from 14% to 22% for irrigated areas and from 25% to 40% for rain-fed areas, which exhibited significant spatial variability. The NRMSE of simulated LAI was between 50% and 63%, which could be explained that the LAI during different growth stages was all included into the accuracy analysis. Several important input parameters (such as TDWI (initial biomass) and SPAN (leaf senescence coefficient)) could be optimized through assimilating remote sensing data into crop model, which could greatly improve the performance of crop model at the regional scale. Our results showed that the WOFOST model is of great potential for simulating the dynamic growth process of winter wheat in China. The calibrated WOFOST provides the dynamic model basis for regional applications, such as assimilating remote sensing data into crop model for crop yield estimation and climate change prediction with crop model. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Climate models
Controlled terms:Agriculture - Biology - Climate change - Computer simulation - Crops - Digital storage - Mean square error - Meteorology - Models - Optimization  - Plants (botany) - Rain - Remote sensing - Temperature
Uncontrolled terms:Accumulated temperatures - Climate change prediction - Coefficient of variation - Different growth stages - Parameter calibration - Phendogy - Winter wheat - WOFOST
Classification code:443  Meteorology - 461.9  Biology - 641.1  Thermodynamics - 722.1  Data Storage, Equipment and Techniques - 723.5  Computer Applications - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4  Agricultural Products - 921  Mathematics - 921.5  Optimization Techniques - 922.2  Mathematical Statistics
Numerical data indexing:Percentage 1.10e+01% to 2.30e+01%, Percentage 1.40e+01% to 2.00e+01%, Percentage 1.40e+01% to 2.20e+01%, Percentage 2.20e+01%, Percentage 2.50e+01% to 4.00e+01%, Percentage 2.80e+01%, Percentage 4.00e+00% to 7.00e+00%, Percentage 5.00e+01% to 6.30e+01%, Percentage 8.00e+00% to 1.20e+01%
DOI:10.11975/j.issn.1002-6819.2017.10.029

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 34>

Accession number:20173304051915
Title:Soil erosion resistance of black locust land with different ages of returning farmland on Loess Plateau
Authors:Sun, Long (1, 2); Zhang, Guanghui (1, 3); Wang, Bing (4); Luan, Lili (3) 
Author affiliation:(1) State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling; 712100, China; (2) State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing; 100085, China; (3) School of Geography, Beijing Normal University, Beijing; 100875, China; (4) State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&amp;F University, Yangling; 712100, China 
Corresponding author:Zhang, Guanghui(ghzhang@bnu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:191-197
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Plant litter has been accumulated greatly along with vegetation restoration on the Loess Plateau. Besides covering soil surface, plant litter can be incorporated into topsoil under natural circumstances by soil splash, sediment deposition, and soil-dwelling animal activities. The distribution (covering soil surface or incorporated into surface soil) and the decomposition of plant litter can modify soil physical properties (including soil detachment capacity and soil erosion resistance) which are closely related to soil detachment process by overland flow. This study was conducted to investigate the effect of vegetation restoration on soil detachment process for black locust (Robinia pseudoacacia L.) stand with different ages of returning farmland on the Loess Plateau. The experiments were performed in the Zhifanggou small watershed (36&deg;46&prime;28&Prime;-36&deg;46&prime;42&Prime;N, 109&deg;13&prime;46&Prime;-109&deg;16&prime;03&Prime;E) in August, 2015. After a complete watershed survey, altogether 6 sampling sites were selected, including 1 corn (Zea mays L.) field and 5 black locust stands of 10, 15, 20, 30, and 40 years. Soil samples were collected from the top 5 cm soil layer using a circular steel ring with 10.0 cm diameter and 5.0 cm depth. Soil detachment was measured in a 4.0 m long, 0.35 m wide flume. Prior to the test of soil detachment capacity, soil samples were saturated in a container for 8 h and drained for 12 h. Then the soil samples were inserted into a hole (0.5 m away from the outlet of flume) on the flume bed and were scoured by flowing water under designed flow shear stress. A total of 180 soil samples were collected from different aged black locust stands and scoured under 6 flow shear stresses. In this study, 6 combinations of flow rates and slopes were applied to obtain 6 different flow shear stresses (5.4-17.4Pa) with similar intervals. Rill erodibility is defined as the increase in soil detachment capacity per unit increase in flow shear stress. Critical shear stress is a threshold parameter defined as the value above which a rapid increase in soil detachment capacity per unit increase in shear stress occurs. When the measured detachment capacity was plotted against the flow shear stress, rill erodibility and critical shear stress could be determined from the slope of the fitted straight line and its intercept on the X axis. The results showed that the density of plant litter in 0-5 cm surface soil was 0.07, 0.18, 0.32, 0.29 and 0.17 kg/m²for 10, 15, 20, 30, and 40-year-old black locust stands, respectively, with the mean value of 0.20 kg/m². The 40-year-old black locust stands had more capillary porosities, soil organic matter, and water stable aggregates, and smaller soil bulk density. Soil detachment capacity decreased by 49.8%, 73.9%, 85.0%, 86.0%, and 87.0% for 10, 15, 20, 30, and 40-year-old black locust stands, respectively, compared to the control. The soil detachment capacity decreased significantly over time as an exponential function (R²=0.97, P=0.006). The control (corn field) had the biggest rill erodibility (0.29 s/m), and the 40-year-old black locust stand had the smallest rill erodibility (0.04 s/m). Compared to the control, the rill erodibility for 40-year-old black locust stand was reduced by 86.3%. The black locust stand with 20 years had the biggest critical shear stress (4.78 Pa), and the control had the smallest critical shear stress (4.15 Pa). The critical shear stress increased by 10.1% for 40-year-old black locust stand compared to the control. The critical shear stress increased significantly with litter density as a linear function (R²=0.67, P=0.046). Rill erodibility was better than critical shear stress in the respect of reflecting the variation of soil detachment. The soil-plant litter system has a larger erosion resistance to flowing water than the control. Importantly, the soil-root system may have a larger structural stability and erosion resistance to flowing water than soil-plant litter system. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Soil conservation
Controlled terms:Erosion - Experiments - Exponential functions - Farms - Landforms - Plants (botany) - Reforestation - Restoration - Sediments - Shear flow  - Shear stress - Soil surveys - Soil testing - Soils - Stability - Vegetation - Watersheds
Uncontrolled terms:Critical shear stress - Farmland afforestation - Loess Plateau - Rill erodibility - Soil detachment
Classification code:444.1  Surface Water - 481.1  Geology - 483  Soil Mechanics and Foundations - 483.1  Soils and Soil Mechanics - 631.1  Fluid Flow, General - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 901.3  Engineering Research - 921  Mathematics
Numerical data indexing:Age 2.00e+01yr, Age 4.00e+01yr, Percentage 1.01e+01%, Percentage 4.98e+01%, Percentage 7.39e+01%, Percentage 8.50e+01%, Percentage 8.60e+01%, Percentage 8.63e+01%, Percentage 8.70e+01%, Pressure 4.15e+00Pa, Pressure 4.78e+00Pa, Pressure 5.40e+00Pa to 1.74e+01Pa, Size 0.00e+00m to 5.00e-02m, Size 1.00e-01m, Size 3.50e-01m, Size 4.00e+00m, Size 5.00e-01m, Size 5.00e-02m, Surface_Density 1.70e-01kg/m2, Surface_Density 2.00e-01kg/m2, Surface_Density 2.90e-01kg/m2, Time 2.88e+04s, Time 4.32e+04s
DOI:10.11975/j.issn.1002-6819.2017.10.025

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 35>

Accession number:20173304051921
Title:Analysis on relationship between wake and fatigue load of wind turbines
Authors:Deng, Ying (1); Li, Jianan (1); Liu, Hesheng (1); Pang, Huiqing (1); Tian, De (1) 
Author affiliation:(1) Renewable Energy Institute, North China Electric Power University, Beijing; 102206, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:239-244
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the continuous development of wind power industry, the power record of single wind turbine is constantly expanded, and the scale of wind power generation is becoming larger and larger. For large wind turbines, the wake effect cannot be ignored. It has an important influence on the fatigue load of the wind turbine, and also has a significant impact on the output power characteristics of the wind turbine. In order to study the influence of wind turbine wake on the load of the downstream wind turbine, several important wake parameters such as upstream and downstream wind turbine spacing, upstream wind turbine thrust coefficient and nature wind speed are assumed according to the theoretical results of some researchers. The physical quantity of wake region can be obtained according to the momentum theory. The relation between the natural wind speed, the wind speed and the thrust coefficient can be obtained by calculating the axial thrust based on the Bates' theory. The wind speed increases linearly with the natural wind speed, but with the increase of the thrust coefficient, the wind speed of the wind rotor will gradually decrease. When the natural wind speed is fixed, with the increase of thrust coefficient, the wind speed of the wind turbine will be reduced, and if the thrust coefficient can be large enough, then the wind speed of the wind rotor will tend to 0. However, there will be no thrust coefficient greater than or equal to 1 in the actual operation of the wind turbine. Use GH Bladed software to build a model of FL1500/70 1.5 and 3.0 MW doubly-fed wind turbine, and calculate the load response of the wake model to the downstream wind turbine. The conclusions are obtained by analyzing the calculation results which are as follows: 1) When the natural wind speed is constant, the wind speed at the wind rotor will decrease nonlinearly with the increase of thrust coefficient. The wake wind speed increases with the distance between 2 wind turbines, but the trend is gradually stabilized. But for different wind rotor radius, the larger the value, the closer to linear variation the relationship curve of wake wind speed and distance. 2) When the wind turbine is in the influence range of the wake, under the same wind speed and thrust coefficient, the farther the distance, the less the load will be affected by wake. In the case of larger absolute value of turbulence intensity difference, the load difference increases with the decrease of turbulence intensity difference, which is due to that the decrease of turbulence intensity under the wake effects makes the load increase; sometimes the load difference decreases with the increase of the difference of turbulence intensity, which means under the wake effect the turbulence increases and at the same time the load is reduced. The reason is when the turbulence increases, the load increases, but at the same time the wind speed affected by the wake effect becomes smaller, so the thrust coefficient decreases, followed by the decrease of the load. Comparing the turbulence intensity with the thrust coefficient, the reduction of thrust coefficient has a more influence on the load. 3) When the thrust coefficient of the upstream wind turbine increases, the load will increase; when the wind speed is greater than the rated wind speed, the thrust coefficient should be reduced by adopting the pitch control so as to reduce the fatigue damage of the wind turbine. 4) Based on the wind turbine modeling and numerical simulation calculation with Bladed software, the influence of upstream wind turbine wake on the fatigue loading of the wind turbine is discussed. The accuracy of this calculation which is used to determine the load response characteristics of wind turbines is limited, but it is very difficult to carry out on-site verification of the fatigue load data of wind turbine. Therefore, the data provided by the chart in this paper are for reference only. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Wind turbines
Controlled terms:Aircraft propulsion - Computer simulation - Computer software - Electric power generation - Fatigue damage - Models - Speed - Turbine components - Turbulence - Wakes  - Wind - Wind effects - Wind power
Uncontrolled terms:Continuous development - Distance - Fatigue loads - Numerical simulation calculation - Thrust coefficients - Turbulence intensity - Wind speed - Wind turbine modeling
Classification code:443.1  Atmospheric Properties - 615.8  Wind Power (Before 1993, use code 611 ) - 617  Turbines and Steam Turbines - 631.1  Fluid Flow, General - 653.1  Aircraft Engines, General - 723  Computer Software, Data Handling and Applications - 723.5  Computer Applications - 951  Materials Science
Numerical data indexing:Power 1.50e+06W, Power 3.00e+06W
DOI:10.11975/j.issn.1002-6819.2017.10.031

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 36>

Accession number:20173304051904
Title:Multi-objective parameters optimization of centrifugal slurry pump based on RBF neural network and NSGA-II genetic algorithm
Authors:Wang, Chunlin (1); Feng, Yiming (1); Ye, Jian (1); Luo, Bo (1); Liu, Keke (1) 
Author affiliation:(1) School of Energy and Power Engineering, Jiangsu University, Zhenjiang; 212013, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:109-115
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the rapid development of national industry and mining, slurry pump is widely applied in transportation of two-phase flow as a sort of practical and reliable fluid machinery. Due to that the medium of centrifugal slurry pumps transport is fluid-solid two-phase medium, there is great difference for internal flow field between centrifugal slurry pumps and clean water pumps. Therefore, the design of the former is more complex and its design theory and method are not perfect now. In terms of performance, the main criticisms are its working head lower than design head, low efficiency and severe wear. So, it is a kind of equipment whose performance should be promoted rapidly in modern safe and effective industrial production. Thus, the optimal design of centrifugal slurry pumps is very meaningful for improving its performance. A centrifugal slurry pump with a specific speed of 75 was chosen as the research object. With the commercial CFD (computational fluid dynamics) software Fluent, RNG k-&Epsilon; turbulence model and Eulerian two-phase flow model were selected to calculate its internal flow. The efficiency and the high efficiency region of the centrifugal slurry pump were set as the optimization goal. Design Expert 8.0.5b was used to make Plackett-Burman screening experimental design to pick out 3 structural parameters from 12 structural parameters of model pump, which were slurry pump blade inlet angle, outlet angle and wrap angle, set as the optimization variables, because too many structural parameters may affect the high efficiency area and the highest efficiency of centrifugal slurry pump. The 37-level uniform experiment was finished and the training and testing samples of RBF neural network were established. RBF (radial basis function) neural network was used to fit the relationship between the variables and objectives, which could be applied in NSGA-II algorithm to get the Pareto optimal solution. Aiming at the result of the optional Pareto solution set, the optimal efficiency individual and high efficiency region individual were selected to compare with the initial model that was not optimized: The difference of external characteristic curves, distribution of absolute pressure at middle section of impeller runner and volute runner, relative velocity vector of fluid and solid phase, distribution of turbulence kinetic energy, distribution of solid concentration of pressure blades, blades back, front shroud and back shroud at middle section of impeller runner were all compared between the 2 extreme value individuals and initial individual. According to the analysis results of the differences between the performance curves of the above 3 individuals, the obtained optimal efficiency blade inlet angle, outlet angle and wrap angle were 21.76&deg;, 23.43&deg;, and 145.56&deg;, respectively, and the high efficiency region blade inlet angle, outlet angle and wrap angle were 19.38&deg;, 22.68&deg;, and 116.71&deg;, respectively. The experiment proved that the efficiency of the optimal individual was improved by 3.81% and the high efficiency region individual was improved by 4.33% compared with the original individual. The optimization results show that this optimization method improves the hydraulic characteristics of the impeller and the performance of centrifugal slurry pump. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Two phase flow
Controlled terms:Centrifugation - Computation theory - Computational fluid dynamics - Computer simulation - Curve fitting - Genetic algorithms - Hydraulic machinery - Impellers - Kinetic energy - Kinetics  - Machinery - Multiobjective optimization - Optimal systems - Optimization - Pareto principle - Pumps - Radial basis function networks - Slurry pipelines - Transport properties - Turbulence models
Uncontrolled terms:CFD (computational fluid dynamics) - Hydraulic characteristic - Multi objective - NSGA-II - Pareto optimal solutions - RBF Neural Network - RBF(radial basis function) - Turbulence kinetic energy
Classification code:601.2  Machine Components - 618.2  Pumps - 619.1  Pipe, Piping and Pipelines - 631.1  Fluid Flow, General - 632.2  Hydraulic Equipment and Machinery - 721.1  Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory - 723.5  Computer Applications - 802.3  Chemical Operations - 921.5  Optimization Techniques - 921.6  Numerical Methods - 931.2  Physical Properties of Gases, Liquids and Solids - 961  Systems Science
Numerical data indexing:Percentage 3.81e+00%, Percentage 4.33e+00%
DOI:10.11975/j.issn.1002-6819.2017.10.014

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 37>

Accession number:20173304051911
Title:Effect of distribution characteristic and field hydraulic connection of drainage ditches and ponds on water quality purification
Authors:Luo, Wan (1); Zhu, Jincheng (1); Jia, Zhonghua (1); Zhou, Meng (1); Lin, Songsen (1); Sun, Shaojiang (1) 
Author affiliation:(1) College of Water Resources and Hydro-Power Engineering, Yangzhou University, Yangzhou; 225009, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:161-167
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Wetlands have been recognized as a functional ecological measure that can reduce agricultural non-point source pollution economically and effectively. Water quality benefit can be achieved by utilizing drainage ditches and ponds that possess certain wetland functions. Different from the constructed wetlands that are designed with optimum hydraulic conditions, the primary functions of drainage ditches and ponds are to provide timely drainage from crop fields for high crop yields. Thus, ditches and ponds are often distributed in a mixed pattern with crop fields, or randomly located within farmlands. Such distribution produces far more complicated hydraulic conditions than the artificial constructed wetland systems, making it difficult to assess the actual pollution reduction capacity of these ditches and ponds. This study was to investigate the effect of distribution and complicated hydraulic connections of drainage ditches and ponds on water quality improvement. The study area was located in Zhaoguan Irrigation Area along the Grand Canal in Yangzhou, China (119&deg;25&prime;E, 32&deg;22&prime;N). In the area, drainage ditches with 100-m interval were divided into squares in 1 hm². During the growing season of rice, the drainage flow had a peak about 0.5 cm/d. The area was 5.61 hm²in total. By investigation, the study area had 3 types of drainage ditch/pond: field ditch, delivery ditch and pond. The pollutant removal rate of ditch/pond system was calculated under 2 conditions. One was ideal hydraulic connection. The drainage was assumed to be concentrated or the crop fields had the area matched with ditches and ponds. In the other condition, the complicated hydraulic connections among every ditch and pond unit were considered as mixed distribution of fields and ditch/pond. The flow was generalized in the latter condition. The detailed flow relationship of drainage ditches and ponds was generalized. Methods for calculating hydraulic retention time and pollutant removal rate under the 2 conditions were proposed. The realization rate was the ratio of the pollutant removal rate by considering hydraulic connections to that with ideal hydraulic connection. The results showed that the total ditch/pond area in this area was 0.80 hm², which was 14.3% of the agricultural field area. The ditch/pond included 18 units: 10 field ditch, 6 delivery ditch and 2 ponds. The field ditch was evenly distributed while the pond and the delivery ditch were around the edge of the fields. A total of 3 branches were in the ditches/ponds system and their distribution was not even. The branch 1 located above the field had 58% ditch/pond area, and the branch 2 accounted for 22% ditch/pond area, and the branch 3 was 20% ditch/pond area. The ratio of ditch/pond to field area was 79% for branch 1, 2% for branch 2 and 19% for branch 3. The branch 1 had longer path and the others had shorter path. The total pollutant retention time was 8.57 d in the system including 0.50 d in the field ditch, 4.02 d in the delivery ditch and 4.05 d in the pond. The contribution of the field ditch to the total retention time was only 6%. As the degradation rate of pollutant increased from 0.01 to 0.3 d^-1, the realization rate decreased from 0.84 to 0.70. The pollutant removal rate considering the hydraulic connections was 70%-84% of that with ideal hydraulic connection. It indicated that the current simplified model for evaluating ditch wetlands may overestimate pollutant retention capacity. The contribution of drainage branches to pollutant removal was different. When the pollutant degradation rate was low, the contribution was nearly positively correlated with ditch/pond area distribution. For the pollutant degradation rate 0.01 d^-1, the branch 1 with 58% ditch/pond area contributed to 58% of the pollutant removal and the branch 2 with 22% ditch/pond area contributed to 22% of the pollutant removal. About 2/3-3/4 of the pollutant was removed in the delivery ditch and 1/5 in pond. The field ditch had the small contribution of 6%-15%. In sum, the ditch and pond with a large area were the main area for pollutant degradation. Findings from this research may provide support for conserving and improving ecological functions of ditches and ponds in agricultural landscape. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:36
Main heading:Water treatment
Controlled terms:Agriculture - Crops - Degradation - Drainage - Ecology - Lakes - Pollution - Ponds - Storm sewers - Water quality  - Wetlands
Uncontrolled terms:Agricultural landscapes - Agricultural non-point source pollutions - Distribution characteristics - Fields - Hydraulic connection - Hydraulic retention time - Pollutant retention capacity - Water quality improvements
Classification code:445.1  Water Treatment Techniques - 445.2  Water Analysis - 452.1  Sewage - 454.3  Ecology and Ecosystems - 802.2  Chemical Reactions - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4  Agricultural Products
Numerical data indexing:Percentage 1.43e+01%, Percentage 1.90e+01%, Percentage 2.00e+00%, Percentage 2.20e+01%, Percentage 5.80e+01%, Percentage 6.00e+00% to 1.50e+01%, Percentage 6.00e+00%, Percentage 7.00e+01% to 8.40e+01%, Percentage 7.90e+01%, Size 1.00e+02m
DOI:10.11975/j.issn.1002-6819.2017.10.021

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 38>

Accession number:20173304051928
Title:Granary storage quantity detection method based on bottom pressure estimation
Authors:Zhang, Dexian (1, 2); Zhang, Miao (1, 2); Zhang, Qinghui (1, 2); Zhang, Yuan (2) 
Author affiliation:(1) School of Information Science and Engineering, Henan University of Technology, Zhengzhou; 450001, China; (2) Grain Information Processing and Control, Key Laboratory of Ministry of Education, Zhengzhou; 450001, China 
Corresponding author:Zhang, Miao(zhangmiao7414@sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:287-294
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Automatic detection of granary storage quantity with fast speed and high accuracy is an important technology for national food security. In this paper, according to the characteristics of grain bulk in different granary type (flat warehouse, squat silo and vertical silo), the mathematical relationship between granary storage quantity and the bottom/side pressure of granaries is established, and a new on line model for the grain storage quantity measurement is also proposed. For the given grain and storage type, the storage quantity is only related to the bottom pressure and side pressure on the granary and the grain height in the granary, which makes it possible to measure the storage quantity with pressure sensors; as long as the above pressure value and grain height are determined, the storage quantity can be obtained with high accuracy. According to the measurement requirement on the accuracy and robustness on the grain storage quantity, the pressure sensors are arranged as 2 circles, and each circle includes multiple pressure sensors. There exist the inhomogeneity and randomness of the pressure value on the bottom and side of the granary, and therefore more sensors are needed which can detect the pressure value on the bottom and side with high accuracy. However, the more the pressure sensor used, the higher the cost of measurement system. Based on the tradeoff on the cost and accuracy, the setup of 2 circles is proposed to measure the pressure value with high accuracy. The inner circle which is far from the side wall provides the pressure value on the granary bottom and the outer circle which is close to the side wall provides the pressure value on the granary side. For this method, the setup of 2 circles not only eliminates the inhomogeneity and randomness of the granary pressure value measurement, but also reduces the number of the required pressure sensors. With the pressure values obtained, according to the principle model of the storage quantity measurement, this paper proposes a new model based on polynomial expansion to measure the storage quantity. The model uses the polynomial of the average of the values output by the inner pressure sensors to estimate the bottom pressure value, uses the polynomial of the average of the values output by the outer pressure sensors to estimate the side pressure value, and obtains the grain height based on the above 2 polynomials. The proposed model can obtain the polynomial coefficient and order based on the test sample of the granary storage quantity automatically, which provides the high accuracy on the grain storage quantity measurement based on the pressure sensors. At the same time, the information of granary type such as granary shape and size is also introduced in the model, which improves the practicality for the granary of different types in the proposed model. Real practical storage quantity detection results show that the detection error of the proposed model is less than 2.5%, and the cost is reduced significantly, which demonstrate that the proposed granary storage quantity detection model is effective and well meets the demand of national granary storage quantity detection. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Food storage
Controlled terms:Costs - Estimation - Food supply - Grain elevators - Models - Polynomials - Pressure - Pressure sensors - Random processes - Sensors  - Walls (structural partitions)
Uncontrolled terms:Automatic Detection - Detection accuracy - Mathematical relationship - Measurement system - Measurement-based - Polynomial coefficients - Polynomial expansion - Principle modeling
Classification code:408.2  Structural Members and Shapes - 694.4  Storage - 822.1  Food Products Plants and Equipment - 822.3  Food Products - 911  Cost and Value Engineering; Industrial Economics - 921  Mathematics - 921.1  Algebra - 922.1  Probability Theory - 931.1  Mechanics - 944.3  Pressure Measuring Instruments
Numerical data indexing:Percentage 2.50e+00%
DOI:10.11975/j.issn.1002-6819.2017.10.038

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 39>

Accession number:20173304051891
Title:Engineering philosophy and design scheme of gully land consolidation in Loess Plateau
Authors:Liu, Yansui (1, 2, 3); Li, Yurui (1, 2, 3) 
Author affiliation:(1) Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing; 100101, China; (2) Center for Assessment and Research on Targeted Poverty Alleviation, Chinese Academy of Sciences, Beijing; 100101, China; (3) University of Chinese Academy of Sciences, Beijing; 100049, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:1-9
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Loess Plateau used to be the area with the most serious erosion in China even world. Erosion area in Loess Plateau was up to 454 000 km², accounting for 70% of the total area in the 1990s. Extremely intensive erosion area with erosion modulus more than 8 000 t/(km²&middot;a) was up to 85 000 km², accounting for 64% of the similar areas in China. Severe erosion area with erosion modulus more than 15 000 t/(km²&middot;a) was up to 37 000 km², accounting for 89% of the similar areas in China. Since 1998, Grain-for-Green Project has been implemented in the Loess Plateau. With the advancement of Grain-for-Green Project, forested land and grassland increase, and farmland decreases. Besides, as the population grows, Grain-for-Green Project has negative effects on grain production in some regions, and the population-grain conflict is intensified. In Yan'an, Shaanxi Province, farmland decreased by 74 000 hm², grain production decreased by 156 000 t, and per capita grain production decreased by 132 kg with an increase of the residential population of 260 000 compared with those prior to the implementation of the project. With the further intensification of the conflict between population and grain, the demand for new agricultural production space is increasing. After decades of implementing Grain-for-Green, the vegetation cover rate increases and the erosion decreases greatly, which creates preconditions for gully land consolidation. Local initiatives of gully land consolidation since 2012 have achieved initial success. Gully land consolidation creates new space for agricultural and rural development. But how to design and plan the gully land consolidation engineering at a large scale and thus make it be approved by the central government needs systematic thinking and research. Taking Yan'an City, Shaanxi Province as a case study, this paper introduces the basic concepts of the gully land consolidation and its enhanced design in the Loess Plateau. Taking "farmland increasement, ecological protection, people's livelihood guarantee" as the theme, and "landscape coordination, structure stability, sustainable land use, effective function" as the concepts, the project highlights the land use zoning, which can be described in detail as "returning farmland to forest on the mountain, consolidating gully to farmland in the valley", and put the emphasis on protecting ecological environment and benefiting local residents' livelihood. In the step of planning and design, the zoning, classification standards and key techniques of gully land consolidation are identified, and 4 project construction types are proposed, which are restoration-type consolidation, facilities-type consolidation, exploitation- type consolidation, and comprehensive management-type consolidation. Furthermore, the enhanced consolidation technology system is also created, which involves "mainstream-tributary-capillary flow" tiered prevention and control technology, "canal-embankment-dam" matching system, and "tree-shrub-grass" scientific collocation. Since the implementation of the major project of more than 2 years, it has generated economic, social and ecological benefits to some extent. To further exert the project's comprehensive benefits, the next 4 major projects need be adopted, namely new rural communities and residential resettlement project, urban and rural equalization of services and service facilities engineering, modern agriculture industrialization base construction, and rural land capitalization and land system innovation. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:23
Main heading:Landforms
Controlled terms:Agricultural engineering - Agriculture - Canals - Consolidation - Ecology - Erosion - Farms - Forestry - Grain (agricultural product) - Housing  - Land use - Project management - Regional planning - Sediments - Zoning
Uncontrolled terms:Agricultural productions - Classification standard - Comprehensive managements - Ecological environments - Grain for green projects - Loess Plateau - Prevention and controls - Yan'an city
Classification code:403  Urban and Regional Planning and Development - 407.2  Waterways - 454.3  Ecology and Ecosystems - 481.1  Geology - 483  Soil Mechanics and Foundations - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4  Agricultural Products - 912.2  Management
Numerical data indexing:Age 2.00e+00yr, Area 3.70e+10m2, Area 4.54e+11m2, Area 8.50e+10m2, Mass 1.32e+02kg, Percentage 6.40e+01%, Percentage 7.00e+01%, Percentage 8.90e+01%
DOI:10.11975/j.issn.1002-6819.2017.10.001

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 40>

Accession number:20173304051892
Title:Design and experiment of 4JSM-2000 type combined operation machine for cotton stalk chopping and residual plastic film collecting
Authors:You, Jiahan (1); Chen, Xuegeng (1, 2); Zhang, Benhua (1); Wu, Jie (3) 
Author affiliation:(1) College of Engineering, Shenyang Agricultural University, Shenyang; 110866, China; (2) Mechanical Equipment Research Institute, Xinjiang Academy of Agricultural and Reclamation Science, Shihezi; 832000, China; (3) College of Mechanical and Electrical Engineering, Shihezi University, Shihezi; 832003, China 
Corresponding author:Chen, Xuegeng(chenxg130@sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:10-16
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to improve the mechanization of the domestic equipment for recycling agricultural plastic film in cotton field of Xinjiang, and solve the common problems existing in traditional plastic film recovery machine including low recovery rate of plastic film, high impurity content of recovered plastic film, difficult to separate stalk and soil from plastic film, plastic film easy to wrap cotton stalk and film collecting parts, and low efficiency, the 4JSM-2000 type cotton stalk chopping and plastic film collecting machine was designed, for collecting residual plastic film with width of 2 050 mm. The designed mainly consisted of suspension device, cotton stalk chopping device, stalk conveying device, loosening film device, film collecting device, film removing device, transmission system, plastic film box, and so on. It could realize cotton stalk chopper returning, plastic film recycling, and soil and straw separation from plastic film with one operation. The machine combined the hammer type stalk chopping device and spiral convey device. The separation effect was good. When the machine operated, the plastic film was lifted from the field by loosening film tooth, and piled up on the end of loosening film tooth. The film collecting device picked up plastic film and delivered it to the film-unloading entrance. The plastic film was unloaded by the cooperation of unloading impeller and film-unloading groove on the cylinder. Strong centrifugal wind produced by high speed rotation of the film unloading roller blew the plastic film in volute into the residual film box. The working parameters of loosening film tooth were determined through the orthogonal test. The penetrating angle, operation depth, and operation speed were taken as 3 factors, and a three-factor and three-level orthogonal test was conducted. In the test, the penetrating angle was 30&deg;, operation depth was 40 mm, operation speed was 6 km/h were the optimal combination. The film collecting device mainly included eccentric shaft, cylinder, retractable finger frame, and so on. The device had high film collecting rate. Through the force analysis, the rotation speed of cylinder should need greater than 97 r/min, if the rotation speed of cylinder was too fast, the retractable finger would broken plastic film, increased the difficulty of recycling, and comprehensive consideration the rotation speed of cylinder was 110 r/min The film uploading device mainly included shaft, uploading film roller, uploading film impeller, volute, and wind increasing hole, and so on. The film unloading device was designed based on the force analysis and experiment, the working speed of film uploading rotation shaft was greater than 1000 r/min. Results of field experiment demonstrated that when the traction speed of tractor was 6.0 km/h, the operating efficiency was 1.15 hm²/h, the qualified rate of cotton straw chopping was 90.1%, when the cutter shaft speed was 2100 r/min, the recovery rate of agricultural plastic film was 84.4%, and the separation ratio of cotton straw and plastic film was 87.3%. The parameters of the machine meet the agricultural requirements. The research results may be helpful for solving the problem of plastic film pollution in cotton field. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:22
Main heading:Plastic recycling
Controlled terms:Agricultural machinery - Agriculture - Collector efficiency - Cotton - Cylinders (shapes) - Efficiency - Impellers - Plastic films - Recovery - Recycling  - Rotation - Separation - Speed - Straw - Tractors (agricultural) - Unloading
Uncontrolled terms:Agricultural plastic films - Combined operations - Domestic equipments - High speed rotation - Operating efficiency - Optimal combination - Stalk chopping - Transmission systems
Classification code:452.3  Industrial Wastes - 601.2  Machine Components - 691.2  Materials Handling Methods - 702.3  Solar Cells - 802.3  Chemical Operations - 817.1  Polymer Products - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 913.1  Production Engineering - 931.1  Mechanics
Numerical data indexing:Percentage 8.44e+01%, Percentage 8.73e+01%, Percentage 9.01e+01%, Rotational_Speed 1.00e+03RPM, Rotational_Speed 1.10e+02RPM, Rotational_Speed 2.10e+03RPM, Rotational_Speed 9.70e+01RPM, Size 2.05e+00m, Size 4.00e-02m, Velocity 1.67e+00m/s
DOI:10.11975/j.issn.1002-6819.2017.10.002

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

<RECORD 41>

Accession number:20173304051925
Title:Rice husk ceramic particles improving lubrication property of liquid paraffin
Authors:Hu, Enzhu (1); Yu, Dongrui (2); Tang, Yuchao (1); Wu, Yun (1); Hu, Kunhong (1); Hu, Xianguo (2); Song, Ruhong (2) 
Author affiliation:(1) Department of Chemical and Materials Engineering, Hefei University, Hefei; 230601, China; (2) School of Mechanical Engineering, Hefei University of Technology, Hefei; 230009, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:10
Issue date:May 15, 2017
Publication year:2017
Pages:265-270
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Comprehensive utilization of rice husk resource is important in resolving serious environmental pollutions induced by arbitrary burning and storage of rice husk. Rice husk ceramic (RHC) particles can be a functional addition in developing high-quality and high-performance engine lubricating oils and comprehensively utilizing rice husk resource. In this study, coarse RHC particles were prepared via co-carbonization of rice husk and phenolic resin with a mass ratio of 3:1 for 2 h at 900&#8451; under N<inf>2</inf>atmosphere. Then, the particles were ground in a planetary ball mill for 30 min to obtain fine RHC particles. Test oil samples including different contents (0.01%, 0.03%, and 0.05%) of RHC particles were prepared using a conventional magnetic stirring method until particles were uniformly dispersed in liquid paraffin (LP). Effects of different contents of RHC particles on lubrication property of LP including 2% Span-80 were investigated using a four-ball tribometer at 200 N load and 1450 r/min rotation speed for 30 min. Test temperatures of 25, 75, and 100&#8451; were selected to simulate the real engine conditions of initial and high-speed operation. Variations in friction coefficient and average wear scar diameter (AWSD) reflected the anti-friction and anti-wear properties of the different oil samples. Scanning electron microscopy/energy dispersive spectroscopy were used to observe the morphologies of wear traces and detect element contents in the wear zones for the different samples, thereby reflecting the wear form of RHC particles on the surface of friction pairs. X-ray photoelectron spectroscopy was used to detect the variations in the element chemical valence and the element's atom contents in wear zones, and clarify the friction and wear mechanisms of RHC particles in LP under different test conditions. Results showed that friction coefficients did not obviously decrease in comparison with the pure LP, however, all AWSD decreased when different contents (i.e. 0.01%, 0.03%, and 0.05 %) of RHC particles were added into LP at 25 and 75&#8451;. Therefore, the anti-wear property of LP was modified at a certain extent. When the temperature was 100&#8451;, all average friction coefficients of different contents of RHC particles in LP decreased from 0.139 (LP) to 0.083, 0.064, and 0.069, respectively, and all AWSD decreased from 0.389 to 0.314, 0.311, and 0.318 mm, respectively. The anti-wear and anti-friction properties of the different contents of RHC particles in LP were obviously better than those of oil samples at 25 and 75&#8451;. The Si element contentt in the wear zones of different oil samples lubricated with LP + 2% Sp-80 + 0.03% RHC at 100&#8451; was 0.51%, respectively. The Si came from the composition of RHC particles. These results indicate that friction induces RHC particles to participate in the formation of boundary lubricating film under high-temperature condition. The RHC particles can be used as a high-temperature friction-modified additive. &copy; 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Wear resistance
Controlled terms:Carbonization - Ceramic materials - Engines - Friction - Liquids - Lubricating oils - Lubrication - Paraffins - Scanning electron microscopy - Tribology  - Wear of materials - X ray photoelectron spectroscopy
Uncontrolled terms:Ceramic particle - Friction reduction - Frictional modifier - Liquid paraffins - Particulates - Rice husk
Classification code:607.1  Lubricants - 607.2  Lubrication - 802.2  Chemical Reactions - 812.1  Ceramics - 931  Classical Physics; Quantum Theory; Relativity - 931.2  Physical Properties of Gases, Liquids and Solids
Numerical data indexing:Force 2.00e+02N, Percentage 1.00e-02%, Percentage 2.00e+00%, Percentage 3.00e-02%, Percentage 5.00e-02%, Percentage 5.10e-01%, Rotational_Speed 1.45e+03RPM, Size 3.18e-04m, Time 1.80e+03s, Time 7.20e+03s
DOI:10.11975/j.issn.1002-6819.2017.10.035

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.