1. Calibration for fish behavior binocular visual observation system based on GA-SVR full vision field model

Accession number: 20192307005284

Title of translation: GA-SVR

Authors: Liu, Shijing (1, 2); Tang, Rong (1, 2); Zhou, Haiyan (1); Liu, Xingguo (1, 2); Chen, Jun (1, 2); Wang, Shuai (1)

Author affiliation: (1) Fishery Machinery and Instrument Research Institute, Chinese Academy of Fishery Sciences, Shanghai; 200092, China; (2) Key Laboratory of Fishery Equipment and Engineering, Ministry of Agriculture, Shanghai; 200092, China

Corresponding author: Chen, Jun(chenjun@fmiri.ac.cn)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 181-189

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: For reducing the calibration error and improving the measurement accuracy of fish behavior observation system, a binocular calibration method based on genetic algorithm-support vector regression (GA-SVR) is proposed to solve the problem of image distortion and light refraction, and realize the indirect calibration of underwater large field of view. In this paper, a standard board with 49 uniformly arranged circular targets points developed by HALCON is chosen for calibration. The diameter of the target is 35.5 mm, the center distance of two targets is 70 mm, and the size of the calibration board is 600 mm×600 mm. Furthermore, in order to reduce the dependence on precision instruments for full-view sampling, a sliding track with bidirectional mobile positioning ability is designed, which is manufactured by the high precision CNC(computerized numerical control) tool with accuracy of 0.05 mm. And along the short axis of the track, 17 pairs of slots are machined at 50 mm intervals to locate the calibration board longitudinal moving distance. A transverse moving bar is erected in the slots, and on which 3 pairs of slots are machined at 400 mm intervals. According to the slot positions, the calibration board is moved along the long axis and the moving rod is moved along the short axis respectively. Sample images are acquired at each slot position, so that the image of the calibration board can cover the whole space of fish tank. The calibration board is used as the basis to collect parallax coordinates and world coordinates, and then the complete sample sets are established in the entire effective vision field of the binocular system. The parallax coordinates of the target points are acquired by Halcon operators, and the relative position information of the calibration board is acquired according to the position of sliding track. The samples of target point used in this study include 2 352 targets from all 49 sample images. The SVR is selected to train the sample set, and three decision function with mathematical expression are established with model parameters calculated by the genetic algorithm. In this article the differential evolution(DE) algorithm, particle swarm optimization(PSO) algorithm and genetic algorithm(GA) are chosen to optimize the SVR parameters, and establish the calibration models respectively. The root mean square error(RMSE), single point error and cross-correlation coefficient are used as evaluation indicators. Based on evaluation results the optimal parameters are selected to establish the position calibration model in X, Y, Z axis respectively. Experimental results show that the genetic algorithm has better optimization effect than the other two algorithms. The mean square errors acquired of X, Y and Z axis are 0.959, 0.893 and 4.381 mm, and the correlation coefficients are 0.999 988, 0.999 998 and 0.998 356, respectively. Compared with traditional calibration methods, the single-point mean square error and distance mean square error of proposed method are 1.861 and 0.706 mm, which are lower than that of calibration method in air (single-point mean square error of 27.75 mm; distance mean square error of 10.188 mm) and underwater calibration methods (single-point mean square error of 8.215 mm; distance mean square error of 2.832 mm). This study could provide reference for quantitative methods of fish behavior. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 33

Main heading: Genetic algorithms

Controlled terms: Binoculars  -  Calibration  -  Computer systems  -  Errors  -  Fish  -  Functions  -  Geometrical optics  -  Image enhancement  -  Mean square error  -  Measurement   -  Models  -  Parameter estimation  -  Particle swarm optimization (PSO)  -  Sampling

Uncontrolled terms: Computerized numerical control  -  Cross-correlation coefficient  -  Differential evolution algorithms  -  Fish behavior  -  Full vision field  -  Particle swarm optimization algorithm  -  Support vector regression (SVR)  -  Visual observations

Classification code: 723 Computer Software, Data Handling and Applications  -  741.1 Light/Optics  -  741.3 Optical Devices and Systems  -  921 Mathematics  -  922.2 Mathematical Statistics

Numerical data indexing: Size 1.02e-02m, Size 1.86e-03m, Size 2.83e-03m, Size 3.55e-02m, Size 4.00e-01m, Size 4.38e-03m, Size 5.00e-02m, Size 5.00e-05m, Size 7.00e-02m, Size 7.06e-04m, Size 8.93e-04m

DOI: 10.11975/j.issn.1002-6819.2019.06.022

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

2. Optimization of coating process parameters for bionic drag reduction and efficiency increasing coating of centrifugal pumps

Accession number: 20192307005268

Title of translation:

Authors: Tian, Limei (1); Zhang, Jixiang (1); Liang, Ying (2); Yao, Guanghai (2); Shang, Yangeng (1)

Author affiliation: (1) Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun; 130022, China; (2) Changchun Ruitai Bionic Technology Co., Ltd, Changchun; 130507, China

Corresponding author: Shang, Yangeng(shangyangeng@163.com)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 47-54

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Bionics is based on the structure of natural biological system and the process of life activities as the basis of technological innovation and design, and consciously imitates and replicates it. Through the coupling of 2 or more different factors, organisms can effectively realize various functional characteristics of organisms and fully display their best adaptability to habitats,this phenomenon of biological coupling is ubiquitous in the biological world. The multi-bionics of learning and simulating the coupling mechanism of organisms is called coupling bionics. The drag reduction mechanism of dolphin skin is a typical representative of the bio-binary coupling. Dolphin skin is composed of smooth elastic keraphyllous epidermis and hard dermis, which are intertwined with each other. The coupling effect of the 2 parts is one of the main reasons why dolphins can swim fast. According to the principle of bionic similarity, Jilin University has designed a coupling functional surface which imitates the skin structure of dolphins, and applied it to the surface of the key parts (centrifugal impeller) of centrifugal pump, which can significantly improve the pump efficiency. The specific method is to directly cast the ribbed structure similar to the dolphin skin dermis on the upper and lower cover plate of impeller by one-step casting technology, and then coat the cover plate with high viscous polyurethane as the surface material. The ribbed structure at the bottom and the polyurethane coating on the surface constitute a coupling bionic functional surface. The thickness parameters of surface material coating have the greatest influence on the efficiency of coatings, and polyurethane is the main material for coating, but because of the complicated and twisted space structure of the inner passage of centrifugal pump impeller, the high viscosity characteristics of polyurethane and the limitation of traditional coating technology, it is difficult to achieve high efficiency and high quality coating on the surface of complex impeller inner runners with coupling bionic functional surface layer materials. and it is difficult to control the thickness of the coating. In order to solve the above problems, a self-made rotating coating equipment by means of centrifugal force was introduced in this paper, using which, the coating thickness could be controlled by pouring temperature, rotating speed, coating time and other parameters. According to the combination design principle of Box-Behnken Design in Design-Expert software, taking the coating thickness of impeller runner as test index, a 3 factors and 3 levels orthogonal combination experiment was designed, the above parameters were optimized and the quadratic fitting equation was established. The test results showed that the main and secondary factors affecting the coating thickness were rotating speed of equipment, pouring temperature and coating duration. The comparative coating tests were carried out on the impeller of 200QJ50-26 centrifugal pump, the results showed that the errors between tested coating thickness controlled by coating parameters and calculated value of quadratic fitting equation was less than 5%, the results were credible. According to the previous research results, when the coating thickness is 0.5 mm, the drag reduction and efficiency increasing of 200QJ50-26 centrifugal pump is the best. The test results showed that the optimum coating parameters for 200 QJ50-26 centrifugal pump to obtain the optimum coating thickness of 0.5 mm were as follows: coating duration was 53.7 s, rotating speed was 401 rad/min, pouring temperature was 90.1. The research can provide a reference for the engineering construction of the coupling functional surface on the centrifugal pump. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 30

Main heading: Coatings

Controlled terms: Biomimetics  -  Bionics  -  Biophysics  -  Centrifugal pumps  -  Dolphins (structures)  -  Drag reduction  -  Efficiency  -  Impellers  -  Plates (structural components)  -  Polyurethanes   -  Pumps  -  Rotating machinery  -  Software testing  -  Thickness measurement

Uncontrolled terms: Centrifugal pump impellers  -  Coating process parameter  -  Elastic coating  -  Engineering constructions  -  Fitting equations  -  Functional characteristics  -  Natural biological system  -  Technological innovation

Classification code: 407.1 Maritime Structures  -  408.2 Structural Members and Shapes  -  461.1 Biomedical Engineering  -  461.9 Biology  -  601.1 Mechanical Devices  -  601.2 Machine Components  -  618.2 Pumps  -  723.5 Computer Applications  -  813.2 Coating Materials  -  815.1.1 Organic Polymers  -  913.1 Production Engineering  -  943.2 Mechanical Variables Measurements

Numerical data indexing: Percentage 5.00e+00%, Size 5.00e-04m, Time 5.37e+01s

DOI: 10.11975/j.issn.1002-6819.2019.06.006

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

3. Effect of intelligent feeder on feed intake, body condition and production performance of lactating sows

Accession number: 20192307005285

Title of translation:

Authors: Wang, Meizhi (1, 2); An, Tao (1, 3); Liu, Jijun (1, 2); Zhang, Jinrui (1); Wang, Wenfeng (4); Yi, Lu (1); Tian, Jianhui (1); Wu, Zhonghong (1)

Author affiliation: (1) College of Animal Science, China Agricultural University, Beijing; 100193, China; (2) State Key Laboratory of Animal Nutrition, Beijing; 100193, China; (3) College of Animal Science, Xinjiang Agricultural University, Urumqi; 830052, China; (4) COFCO Meat Investment Co. Ltd, Beijing; 100020, China

Corresponding author: Wu, Zhonghong(wuzhh@cau.edu.cn)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 190-197

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: During lactation period, body mass and backfat loss of lactating sows were relatively severe, improving the feed intake of lactating sows is the key to improving performance of lactating sows and piglets. With the rapid development of large-scale and intensive breeding pig farms in China, the demand for intelligent feeding equipments have been increased, intelligent feeding equipments can not only save labors but also can increase the feed intake of lactating sows. In order to explore the effect of intelligent feeding on feed intake, body condition and production performance of lactating sows, different feeding modes of feed intake, reproductive performance, water consumption of sows and growth rate of piglets were measured and analyzed. 40 healthy first-born sows, including 13 Landrace pigs and 27 Large White pigs, were selected and randomly divided into 3 groups, there were 15 sows in the test group 1(5 Landrace pigs and 10 Large White pigs), 13 sows in the test group 2(4 Landrace pigs and 9 Large White pigs) and 12 sows in the control group (4 Landrace pigs and 8 Large White pigs).Test group 1 was fed with intelligent feeder (6 times per day), test group 2 was fed artificial (6 times per day) and control group was fed artificial (3 times per day). Sows in control group were fed at 7:00, 10:30 and 17:00, respectively, the amount of feeding per meal was same and was 1/3 of the total amount of feeding per day, from 1 to 7 d after farrowing, sows were fed with restricted feeding, from 8 to 21 d of lactation(weaning age), sows were fed with step up feeding scheme, the feed offered at each meal was adjusted according to the condition of the former meal, if there was no residue of feed in the feeder, the feed offered at this meal would be added within 200 g, the total feeding amount of the next day was 300-500 g more than that of the previous day in all. If there was residue more than 50% of the feed offered, a small amount of feeding or no feeding was required in the next meal. Sows in teat group 1 were fed at 5:00-7:00, 8:00-10:00, 11:00-13:00, 14:00-16:00, 17:00-19:00 and 20:00-22:00, respectively, the percent of each meal was 30%, 10%, 10%, 10%, 30% and 10% of the feed should be offered in one day, respectively. From 1 to 21 d of lactation, feed offered each day was given according to the setting feed offered. The feed offered at each meal was adjusted according to the condition of the former meal and the feed offered previous day, If the first feeding was finished according to the setting value, the feeding amount would be increased by one grade (10% of the feeding amount on the same day) and reduced by one grade if there was leftovers. Sows in test group 2 were fed at 7:00, 8:30, 10:30, 14:00, 17:00 and 20:00, respectively, and the feed offered at each meal was 1/6 of the feed offered one day. From 8 to 21 d of lactation, the feed offered at each meal was adjusted according to the condition of the former meal, if there was no residue in the feeder, the feed offered at this meal would be added within 100 g,feed offered one day would be 300~500 g more than that of the previous day in all. If there was residue more than 50% of the feed offered, no feeding was offered for the next meal. The results showed that the feed intake of artificial feeding for 3e times per day (6.46 kg) was significantly higher than that of intelligent feeding for 6 times per day (5.22 kg) under the experimental environment during the lactation days of 8-21 d (P0.05). But intelligent feeding for 6 times per day was slightly better than artificial feeding for 3 times per day in backfat change, days of estrus after weaning and average daily gained of body mass of one piglet. Ad libitum fed after farrowing perhaps could lead to anorexia which can affect the feeding intake and body condition negatively. It was necessary to use intelligent feeders under such conditions like simulating excellent experienced workers when excellent experienced workers were not easy to hire and in research work which need to collect feed parameters. Under the existing equipment investment and wage level, the intelligent feeder could replace an excellent breeder with the normal use of 4.5 a. The results can provide reference for intelligent feeding to replace experienced artificial feeding and to select feeding methods according to feeding conditions in the future. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 31

Main heading: Feeding

Controlled terms: Animals  -  Mammals  -  Nutrition  -  Testing

Uncontrolled terms: Apparatus  -  Equipment investment  -  Experimental environment  -  Feeding conditions  -  Improving performance  -  Lactating sows  -  Production performance  -  Reproductive performance

Classification code: 461.7 Health Care  -  691.2 Materials Handling Methods

Numerical data indexing: Mass 1.00e-01kg, Mass 2.00e-01kg, Mass 3.00e-01kg to 5.00e-01kg, Mass 5.22e+00kg, Mass 6.46e+00kg, Percentage 1.00e+01%, Percentage 3.00e+01%, Percentage 5.00e+01%

DOI: 10.11975/j.issn.1002-6819.2019.06.023

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

4. Rotating core loss model for motor considering skin effect and dynamic hysteresis effect

Accession number: 20192307005271

Title of translation:

Authors: Song, Ze (1); Li, Yongjian (1); Zhang, Changgeng (1); Liu, Yang (2)

Author affiliation: (1) State Key Laboratory of Reliability and Intelligence of Electrical Equipment School of Electrical Engineering, Hebei University of Technology, Tianjin; 300130, China; (2) Global Energy Interconnection Research Institute, Beijing; 102211, China

Corresponding author: Li, Yongjian(liyongjian@hebut.edu.cn)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 74-80

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: In order to improve the efficiency of agricultural electrical equipment and reduce energy consumption, many scholars attempt to estimate the iron loss accurately. The analysis of finite element showed that in rotational electric machines total core loss comprised alternating core loss and rotational core loss. Precise measured value and modeling of rotational core loss in electrical steel sheets and rotating electrical machines is very important to design and optimize the kind of agricultural motor. According to the separated core loss model under alternative excitation, the core loss can be separated into hysteresis loss, eddy current loss and excess loss. As for alternating core loss, the specific core loss with a circular magnetic flux density can also be separated into 3 portions: the rotational hysteresis loss, the rotational classical eddy-current loss and the rotational excess loss. By means of fourier analysis, the rotating core loss model which considered the influence of alternating and rotating magnetic field, skin effect, dynamic hysteresis loop and minor hysteresis loop was proposed in this paper. Actually, the static hysteresis loop and the dynamic hysteresis loop are different, when the flux density is in saturation, the hysteresis loop shape will be changed. In order to consider the complex behavior of dynamic hysteresis, variable coefficient hysteresis loss was used in the model. The classic exponential coefficient were chosen to be substituted in to the 3 parameters polynomial and fitted out the rotational hysteresis loss with the logarithm. Considering the impact of skin effect at high frequencies, eddy-current loss coefficient were corrected in the paper. Minor hysteresis loop generated by the massive harmonic components leaded the inaccurate prediction of the core loss, the influence of minor hysteresis loop was described by the modified coefficient in the improved formulations, and the modified coefficient was related to the ratio of local flux density to flux density amplitude. By applying orthogonal decomposition technology, 2 mutually orthogonal magnetic flux field was used to describe elliptical rotating magnetic field and replace the rotating loss data. Taking an object affected by the elliptical flux density as an example, the applied magnetic field intensity might not be an elliptical vector because of the nonlinear magnetic flux density-magnetic field intensity relationship and magnetic anisotropy, when it was expanded into a fourier series, however, it shown that the higher harmonics of magnetic field intensity did not contribute to the total core loss as long as magnetic flux density only contains the basic components, the total core loss under the elliptical flux was the summation of alternating core loss and rotating core loss. In order to verify the accuracy of the improved model, a new 3D magnetic properties measurement system was used to measure the rotating core loss of electrical sheet steels. The 3D excitation structure consisted of 3 orthogonal C-shaped cores, 6 multilayer excitation coils which were wound around core poles, a sensing box with built-in core material was placed in the center of 3D magnetic properties measurement device, 6 thin pieces, named as protective layer of uniform magnetic field were fixed around the specimen to make the measured field more uniform at the surface of specimen. Experimental results showed that compared with the classical model and the improved model considering the single factor of skin effect or hysteresis loops only, the accuracy of core loss calculation value of the proposed model was increased by 25.32% and 9.16%, respectively, especially under the condition of high flux density and high frequency. When the frequency was 50 Hz, compared with the classical model, the accuracy of core loss calculation value of the proposed model was increased by 9.21%, and the accuracy was increased by 39.76% at 200 Hz. The comparison of measured value between alternating core loss and rotational core loss showed that the energy of magnetic domain could not accumulated to the maximum in a fixed direction that would lead to irreversible magnetic domain conversion under alternating excitation, which resulted in the increase of hysteresis loss with the increase of magnetic density. The research results can provide reference for the design and optimization of agricultural electrical equipment. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 33

Main heading: Electric losses

Controlled terms: Agriculture  -  Coremaking  -  Eddy currents  -  Electric machine theory  -  Electric machinery  -  Energy efficiency  -  Energy utilization  -  Experiments  -  Fourier analysis  -  Fourier series   -  Hysteresis  -  Hysteresis loops  -  Magnetic anisotropy  -  Magnetic cores  -  Magnetic domains  -  Magnetic fields  -  Magnetic flux  -  Models  -  Rotating machinery  -  Separation   -  Silicon steel  -  Skin effect

Uncontrolled terms: Core loss  -  Dynamic hysteresis loops  -  Magnetic-field intensity  -  Orthogonal decomposition  -  Reduce energy consumption  -  Rotating electrical machines  -  Rotating magnetic fields  -  Static hysteresis loops

Classification code: 525.2 Energy Conservation  -  525.3 Energy Utilization  -  534.2 Foundry Practice  -  545.3 Steel  -  601.1 Mechanical Devices  -  701.1 Electricity: Basic Concepts and Phenomena  -  701.2 Magnetism: Basic Concepts and Phenomena  -  802.3 Chemical Operations  -  821 Agricultural Equipment and Methods; Vegetation and Pest Control  -  901.3 Engineering Research  -  921 Mathematics  -  921.3 Mathematical Transformations  -  961 Systems Science

Numerical data indexing: Frequency 2.00e+02Hz, Frequency 5.00e+01Hz, Percentage 2.53e+01%, Percentage 3.98e+01%, Percentage 9.16e+00%, Percentage 9.21e+00%

DOI: 10.11975/j.issn.1002-6819.2019.06.009

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

5. Yield increasing effect of precision automatic fertilization and micro-spray irrigation for winter wheat-summer maize in large-scale

Accession number: 20192307005274

Title of translation: -

Authors: Xing, Suli (1); Du, Jinzhong (2); Liu, Mengchao (1); Jia, Liangliang (1); Liu, Xuetong (1); Zhao, Shicheng (3)

Author affiliation: (1) Institute of Agro-resources and Environment, Hebei Academy of Agricultural and Forestry Sciences, Shijiazhuang; 050051, China; (2) Gaocheng District Agricultural Bureau of Shijiazhuang City, Shijiazhuang; Hebei Province; 050000, China; (3) Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing; 100081, China

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 100-106

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: To illustrate the agronomic and economic effects of precision automatic fertilization and micro-spray irrigation technology on the winter wheat and summer maize, 3 field experiments were conducted in Beimeng village(38°14’24.87’’N, 114°46’56.41’’E), Fengshang village(38°13’ 21.6’’N, 114°46’48’’E) and Wangxia village(38°2’44.17’’N, 115°25’32.98’’E) in Xinji City Gaocheng District from October 2016 to June 2018. Each experiments including 2 treatments of CK and precision automatic fertilization and micro-spray irrigation treatment, the plot area is 6.67 hm2 for each treatment with 3 replication at random arrangement. The study areas belongs to the typical winter wheat and summer maize rotation in the northern North China Plain, and belongs to the semi-humid climate in warm temperate zone. The average annual temperature is 12.4-12.6 , the accumulated temperature is 4 181-4 863 , the annual precipitation is 488.2-498 mm, and the frost-free period is 190-209 days. The winter wheat sown in mid-October, and harvested in next mid-June, the maize sown in mid-June and harvested from the end of September to the beginning of October. Totally 2 winter wheat-summer maize rotation seasons were included in this experiments. For CK treatment, the fertilization rates and allocation budgets were based on farmers’ survey in the experiments areas. The winter wheat fertilization rates was N 216, 231 and 268.5 kg/hm2, P2O5 112.5, 120 and 105 kg/hm2, and K2O 112.5, 37.5 and 75 kg/hm2 respectively for each teat sites. All the P and K fertilizer applied before sowing, 52%-61% N as basal fertilizer applied before sowing and 39%-48% applied at shooting stage as topdressing. The summer maize fertilization rates were N 306, 318 and 294 kg/hm2, P2O5 36, 48 and 60 kg/hm2, K2O 36, 24 and 48 kg/hm2 respectively for each teat sites, all the P and K fertilizers applied as basal fertilizer, 53%-57% N as basal fertilizer applied before sowing and 43%-47% applied at 10 leaf stage as topdressing. The irrigation strategy for CK treatment was flooding irrigation. For precision automatic fertilization and micro-spray irrigation, fertilization rates and allocation budgets were based on agriculture experts knowledge. The winter wheat fertilization rates were N 157,180 and 180 kg/hm2, P2O5 90, 90 and 101.5 kg/hm2, K2O 52.5, 75 and 75 kg/hm2 for each teat site. The allocation proportion for N as basal fertilizer, jointing stage topdressing and booting stage topdressing was 42.5%, 42.5% and 15%, respectively. P2O5 was 65%, 5%, 30%, respectively. K2O was 60%, 20%, 20%, respectively. The summer maize fertilization rates were N 210, 240 and 270 kg/hm2, P2O5 37.5, 43.5 and 45 kg/hm2, K2O 52.5, 60 and 67.5 kg/hm2 for each teat sites. The allocation proportion for N as basal fertilizer, 10 leaf stage topdressing and flowering stage topdressing was 50%, 45% and 5% respectively, P2O5 was 60%, 20% and 20% respectively, K2O was 50%, 30% and 20% respectively. For this treatment, the precision automatic fertilization and micro-spray irrigation was used in the whole growth seasons, fertilizers were accompanied with the irrigation water through the automatic irrigation channel system. The results showed that large scale the precision automatic fertilization and micro-spray irrigation technology used on winter wheat and summer maize could increase the crop yield, decrease the N, P fertilizer application and irrigation water amount, improve the net benefit. Compared with CK, the precision automatic fertilization and micro-spray irrigation technology significantly increased winter wheat yield by 10.6%, increased net income by 43.77%, significantly reduced the production cost by 26.17%, reduced the amount of nitrogen and phosphorus by 24.20%, decreased the irrigation water by 57.45%. Correspondingly, precision automatic fertilization and micro-spray irrigation technology significantly increased summer maize yield by 13.73%, maize net benefits increased by 13.73%, reduced the production cost by17.09%, reduced the amount of nitrogen and phosphorus by 20.34%, decreased the irrigation water by 36.94% than the CK treatment. For the whole winter wheat and summer maize rotation season, the precision automatic fertilization and micro-spray irrigation technology significantly increased the crop yield by 12.26%, increased the net benefits by 37.39%, reduced the production cost by 21.85%, reduced the amount of nitrogen and phosphorus by 22.26%, reduced the irrigation water by 46.51%. This study confirmed the effect of precision automatic fertilization and micro-spray irrigation technology on winter wheat and summer maize, which can provides reference basis for the promotion of this new technology, thus promoting productivity and agricultural sustainable development. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 32

Main heading: Irrigation

Controlled terms: Budget control  -  Cost reduction  -  Crops  -  Economic and social effects  -  Fertilizers  -  Phosphorus  -  Plants (botany)  -  Rural areas  -  Water  -  Water management

Uncontrolled terms: Accumulated temperatures  -  Annual precipitation  -  Automatic irrigation  -  Nitrogen and phosphorus  -  Precision automatic fertilization  -  Summer maize  -  Winter wheat  -  Yield-increasing

Classification code: 804 Chemical Products Generally  -  821.3 Agricultural Methods  -  821.4 Agricultural Products  -  971 Social Sciences

Numerical data indexing: Age 5.21e-01yr to 5.73e-01yr, Percentage 1.06e+01%, Percentage 1.23e+01%, Percentage 1.37e+01%, Percentage 1.50e+01%, Percentage 2.00e+01%, Percentage 2.03e+01%, Percentage 2.19e+01%, Percentage 2.23e+01%, Percentage 2.42e+01%, Percentage 2.62e+01%, Percentage 3.00e+01%, Percentage 3.69e+01%, Percentage 3.74e+01%, Percentage 3.90e+01% to 4.80e+01%, Percentage 4.25e+01%, Percentage 4.30e+01% to 4.70e+01%, Percentage 4.38e+01%, Percentage 4.50e+01%, Percentage 4.65e+01%, Percentage 5.00e+00%, Percentage 5.00e+01%, Percentage 5.75e+01%, Percentage 6.00e+01%, Percentage 6.50e+01%, Size 4.88e-01m to 4.98e-01m

DOI: 10.11975/j.issn.1002-6819.2019.06.012

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

6. Design of steering control system for rice transplanter equipped with steering wheel-like motor

Accession number: 20192307005264

Title of translation:

Authors: He, Jie (1); Zhu, Jinguang (2); Luo, Xiwen (1); Zhang, Zhigang (1); Hu, Lian (1); Gao, Yang (2)

Author affiliation: (1) Key Laboratory of Key Technology on Agricultural Machine and Equipment, Ministry of Education, South China Agricultural University, Guangzhou; 510642, China; (2) Lovol Heavy Industry Co., Ltd, Weifang; 261200, China

Corresponding author: Zhu, Jinguang(zhujinguang@lovol.com)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 10-17

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: The steering wheel-like motor has been used as steering control mechanism for agricultural machinery navigation systems integrated in small and medium-sized dryland tractors, but it’s adaptability for large-power paddy agricultural machinery or other agricultural machinery with large steering damping remains to be studied. Taking Iseki PZ-60 rice transplanter as the research objective, the steering control system based on steering wheel-like motor is designed in accordance with the steering control characteristic of the automatic navigation rice transplanter working in paddy field. The steering system is composed of steering wheel-like motor, steering controller and wheel angle sensor. The steering system model based on system in series with first-order inertia and integral system is identified in Matlab. First a step signal is applied to the front wheels while the transplanter is lift and with no-load, then the step responses of the steering angle are obtained for 28° to left and 28° right; Afterwards, the model parametersare identified by the MATLAB System Identification toolbox, which turns out that the best fit coefficient of the model (best fits) are 91.07% and 90.12%. A nested control algorithm with dead zone is designed. The inner loop of the algorithm is a PID speed control loop, and the outer loop is an incremental PID angle control loop. Given the control disturbance generated by the gap, free stroke and other nonlinearity in the steering system, the disturbance is regarded as the control dead zone, whose threshold have been tested and integrated into the control algorithm. Simulation del of the system is constructed by MATLAB/Simulink, and the simulation tests are carried out by using square wave and sine wave signals. The results show that tracking delay and adjustment time of the simulated model are about 0.1 s and 0.1 s respectively which indicates that the control system has a good steady-state performance. In other words, the feasibility of the control algorithm is verified. In order to verify the practical performance and control accuracy of the steering control system, the automatic navigation transplanter (including dual antenna differential GNSS system, the navigation controller and the steering control system mentioned above) is adopted to test in the Zengcheng Experimental Base of South China Agricultural University. Three verification tests are carried out on the developed automatic navigating transplanter. The steering signals to be performed in paddy field are sinusoid with amplitude of 10°, small-angle for testing tracking straight line and wide-angle for testing turning round. The results illustrate that the average absolute error (AAE) of sinusoidal signal tracking is 0.301 5° and average delay is 0.3 s; the AAE of straight-line tracking in paddy field conducted on flat and uneven bottom layer are 0.354° and 0.663° respectively, and maximum error of which are 1.4° and 3.6°, respectively with presence of 0.6 s delay; the delay goes up to 1.4 s when transplanter are driven into area with relatively deep mud; the settling time and steady-state error are 2.5 s and 0.6% respectively during the process of tracking a turning signal with 28° steering angle. Three experiments illustrate that the steering system developed for the rice transplanter based on the steering wheel-like motor has good dynamic response and control stability which can be applied to the automatic steering control of the rice transplanter in paddy fields and satisfies operation requirements of automatic navigation for rice transplanter. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 32

Main heading: Controllers

Controlled terms: Agricultural machinery  -  Agriculture  -  Antennas  -  Control engineering  -  Errors  -  Identification (control systems)  -  MATLAB  -  Navigation  -  Navigation systems  -  Proportional control systems   -  Religious buildings  -  Wheels

Uncontrolled terms: Agriculture machinery  -  Automatic steering control  -  Navigation controllers  -  Rice transplanter  -  Steady state performance  -  Steering control  -  Steering control system  -  Steering wheel

Classification code: 402.2 Public Buildings  -  601.2 Machine Components  -  731.1 Control Systems  -  732.1 Control Equipment  -  821 Agricultural Equipment and Methods; Vegetation and Pest Control  -  821.1 Agricultural Machinery and Equipment  -  921 Mathematics

Numerical data indexing: Percentage 6.00e-01%, Percentage 9.01e+01%, Percentage 9.11e+01%, Time 1.00e-01s, Time 1.40e+00s, Time 2.50e+00s, Time 6.00e-01s

DOI: 10.11975/j.issn.1002-6819.2019.06.002

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

7. Numerical analysis of natural convection cooling effect in closed cavity of electronic equipment

Accession number: 20192307005288

Title of translation:

Authors: Wang, Ye (1, 2); Zhao, Xingjie (1); Lin, Huxiang (1); Song, Rongfei (1); Guan, Guoxiang (1)

Author affiliation: (1) School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou; 730070, China; (2) Key Laboratory of Railway Vehicle Thermal Engineering, Ministry of Education, Lanzhou Jiaotong University, Lanzhou; 730070, China

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 214-221

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Natural convection in closed cavity has been received considerable attention due to its widely applications in industry, such as in solar energy collectors design, cooling of electronic instruments, energy saving of building and nuclear reactor design, the study of natural convection mechanism in enclosed cavity is of great practical significance for improving the comprehensive performance of these systems. With the rapid development of science and technology, more and more heat sources and components are located in the same enclosed cavity, which will lead to large number of heat generation. How to arrange the heat source elements is very important to the cooling and reliability of the system by the natural convection heat transfer. Lots of studies have shown that the fins attached to the vertical walls inside the cavity can enhance the heat transfer rate in the cavity. In order to study the effect of the material and space position of heat radiation in enclosed space on the heat transfer characteristics of natural convection, the RNG k-Ε model of FLUENT14.5 was adopted to analyze the temperature field, flow field, local Nusselt numbers and the average Nusselt numbers of the vertical wall of the air-filled cavity (left side was hot wall, right side was cold wall and the top side was the heat source) with aspect ratio of 1. The results showed that the heat transfer enhancement of the cavity was strongly dependent on the position and material of the fins attached to the vertical walls. The influence of single fin and double fin on the horizontal velocity near the top of the cavity was weak, and the disturbance to the horizontal velocity field near the bottom of the cavity was intense, and the influence trend was very close. This phenomenon was not consistent with that of without heat source. The effect of fins on the horizontal velocity in the core region of the cavity was quite different: the disturbance of single fin on the lower position of the core region of the cavity was more obvious, while the disturbance of double fins on the upper region was more intense. Different number of fins lead to different distribution characteristics of temperature field in the enclosed cavity by changing the flow field structure. When the adiabatic fin was located at 1/6 height above the bottom of the hot wall, the average heat transfer capacity of the hot wall was the strongest. When the heat conducting fin was located at 1/3 height above the bottom of the hot wall, the average heat transfer capacity of the hot wall was the strongest. The combination of 1/3 height above the bottom of the hot wall and 2/3 height above the bottom of the cold wall made the average heat transfer capacity of the hot wall the strongest. The average Nu number of thermal conductive fins arranged at 1/3 height above the bottom of the hot wall was maximum, which was 34.93 and 9.67% higher than that of adiabatic fin arranged at the same location. The average Nu number of thermal conductive fins arranged at 1/3 height above the bottom of the hot wall and 2/3 above the bottom of the cold wall was maximum, which was 14.3% and higher than that of thermal conductive fins arranged only at 1/3 above the bottom of the hot wall. The study has a certain theoretical significance for improving the natural convection cooling effect of electronic components in industrial and agricultural engineering and optimizing the spatial location of heat dissipation components. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 32

Main heading: Walls (structural partitions)

Controlled terms: Aspect ratio  -  Computer simulation  -  Cooling systems  -  Electronic cooling  -  Electronics industry  -  Energy conservation  -  Fins (heat exchange)  -  Flow fields  -  Heat conduction  -  Heat convection   -  Heat radiation  -  Natural convection  -  Nuclear reactors  -  Nusselt number  -  Oscillators (electronic)  -  Solar energy  -  Structural design  -  Temperature  -  Velocity

Uncontrolled terms: Comprehensive performance  -  Development of science and technologies  -  Different distributions  -  Enclosed cavity  -  Heat transfer characteristics  -  Heat Transfer enhancement  -  Natural convection cooling  -  Solar energy collectors

Classification code: 408.1 Structural Design, General  -  408.2 Structural Members and Shapes  -  525.2 Energy Conservation  -  616.1 Heat Exchange Equipment and Components  -  631.1 Fluid Flow, General  -  641.1 Thermodynamics  -  641.2 Heat Transfer  -  657.1 Solar Energy and Phenomena  -  713.2 Oscillators  -  723.5 Computer Applications

Numerical data indexing: Percentage 1.43e+01%, Percentage 3.49e+01%, Percentage 9.67e+00%

DOI: 10.11975/j.issn.1002-6819.2019.06.026

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

8. Evaluation of potential pollution risk and source analysis of heavy metals in paddy soil and rice

Accession number: 20192307005286

Title of translation:

Authors: Ao, Ming (1, 2); Chai, Guanqun (1); Fan, Chengwu (1); Liu, Guihua (1); Qin, Song (1); Wang, Ping (2)

Author affiliation: (1) Institute of Soil and Fertilizer, Guizhou Academy of Agricultural Sciences, Guiyang; 550006, China; (2) The Management Station of Agricultural Resource Environment, Guiyang; 550001, China

Corresponding author: Wang, Ping(45940970@qq.com)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 198-205

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: The characterization and spatial distribution of the content and source of heavy metals in soils are necessary to assess the potential threat of heavy metals to food safety and human health. In order to investigate the origin of heavy metals in paddy soils and rice in the Duyun city, 110 sampling sites were set in this study. The soil samples in arable layer of paddy and rice were collected, the contents of Cd, Hg, As, Pb and Cr were measured, and the data were analyzed by the multivariate statistical technique. A geographic information system (GIS) was used to explore the variety of spatial distributions for 5 heavy metals. Single factor pollution index, Nemero comprehensive pollution index and potential ecological risk index were applied to evaluate the degree of soil heavy metal contamination. Our results showed that the average contents of Cd, Hg, As, Pb and Cr in soils in the Duyun were (0.45±0.48), (0.23±0.29), (11.94±10.86), (36.95±32.98) and (60.80±31.73) mg/kg, respectively. The average contents of Cd, Hg, As, Pb and Cr in rice were (38.91±86.50), (5.82±2.96), (113.26±27.18), (89.42±24.87) and (175.92±82.12) μg/kg, respectively. The proportion of Cd, Hg, As, Pb and Cr contents more than the background values of the Guizhou province were 14.55%, 40.00%, 16.36%, 22.72%, 13.64%, respectively. Anthropic activities caused the enrichment of Hg in paddy soils. Only 3.64% of all rice samples exhibited Cd content exceeding the threshold level (20 μg/kg) in the Chinese national guidelines for cereals, and the other elements were below the national limit. Distribution maps of heavy metal content were generated using the Kriging interpolation method to identify their distribution trends. The results show that the influence of smelting activities, transport services and coal combustion on the spatial distribution. These suggested that the impacts of human activities on soil heavy metals in Duyun had exceeded the impact of natural source. Multivariate and geostatistical analysis suggested that soil Cr had a lithogenic origin. The correlation analysis and principal component analysis suggested that Cd, Hg, As and Pb could be attributed to anthropogenic inputs. The accumulation of Cd, Hg and As in soils was mostly affected by lead-zinc smelting, coal combustion and agronomic practices, and the main sources of Pb were lead-zinc smelting, industrial fume, coal burning exhausts. The current study confirmed that the environmental quality could be seriously threatened by heavy metal contaminants from the smelter and industrial activity. Therefore, the use of fossil fuels (coal and oil), fertilizers and the “three wastes” emissions from the key industrial enterprises in this area should be strictly controlled. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 43

Main heading: Soil pollution

Controlled terms: Chemical contamination  -  Coal  -  Coal combustion  -  Health risks  -  Heavy metals  -  Industrial emissions  -  Interpolation  -  Lead smelting  -  Metal analysis  -  Multivariant analysis   -  Oils and fats  -  Principal component analysis  -  Risk assessment  -  Soil surveys  -  Soils  -  Spatial distribution  -  Waste incineration  -  Zinc smelting

Uncontrolled terms: Environmental quality  -  Geostatistical analysis  -  Industrial activities  -  Kriging interpolation methods  -  Multivariate statistical techniques  -  Potential ecological risk  -  Rice  -  Source analysis

Classification code: 451.1 Air Pollution Sources  -  452.4 Industrial Wastes Treatment and Disposal  -  461.7 Health Care  -  483.1 Soils and Soil Mechanics  -  524 Solid Fuels  -  531 Metallurgy and Metallography  -  533.2 Metal Refining  -  804.1 Organic Compounds  -  822.3 Food Products  -  914.1 Accidents and Accident Prevention  -  921 Mathematics  -  921.6 Numerical Methods  -  922 Statistical Methods  -  922.2 Mathematical Statistics

Numerical data indexing: Percentage 1.36e+01%, Percentage 1.46e+01%, Percentage 1.64e+01%, Percentage 2.27e+01%, Percentage 3.64e+00%, Percentage 4.00e+01%

DOI: 10.11975/j.issn.1002-6819.2019.06.024

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

9. Early prediction of winter wheat yield with long time series meteorological data and random forest method

Accession number: 20192307005281

Title of translation:

Authors: Liu, Junming (1, 3); He, Xiaotong (1, 3); Wang, Pengxin (2, 3); Huang, Jianxi (1)

Author affiliation: (1) College of Land Science and Technology, China Agricultural University, Beijing; 100083, China; (2) College of Information and Electrical Engineering, China Agricultural University, Beijing; 100083, China; (3) Key Laboratory of Remote Sensing for Agri-Hazards, Ministry of Agriculture, Beijing; 100083, China

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 158-166

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Early prediction of winter wheat yield is of great significance for the formulation of precise management decisions for the whole growth period of winter wheat. The yield of winter wheat is affected by production technology level and climatic conditions. This study analyzed the feasibility of early prediction of winter wheat yield with long time series meteorological data and random forest method in Henan Province. Winter wheat was planted in a total of 106 counties (cities) in Henan province. Based on the ground observation meteorological data and the winter wheat statistical yield data from the year of 1990 to 2015, we extracted 47 climatic factors such as temperature, humidity and precipitation in different growth stages from wheat jointing to heading stage, and 3 spatial factors of latitude, longitude and elevation. A total of 50 parameters were used as a set of feature variables. The actual yield, meteorological yield and relative meteorological yield were used as the target variables respectively, and a random forest yield prediction model with multiple variables was constructed. The data from the year of 1990 to 2009 were used as training samples to construct the model and the forests constructed were validated with data from the year of 2010 to 2015. The yield impact factors were analyzed by combining the data importance results outside the bag. The results showed that: 1) The prediction results by using meteorological yield and relative meteorological yield as the target variables were better than the yield model. For the meteorological yield and relative meteorological yield models, the values of determination coefficient R2 were both above 0.8, the values of mean absolute error (MAE) and root mean square error (RMSE) of meteorological yield were 415 and 558 kg/hm2, respectively, and the values of MAE and RMSE of relative meteorological yield were 0.07 and 0.09, respectively; 2) The spatial characteristics played an important role in the improving the random forest yield model. However, if the model included only spatial parameters, the predicted values were horizontally distributed along 1:1 line and the different yields in the same region by using random forest algorithm were predicted as the same values. The values far from 1:1 line might be affected by meteorological factors. Therefore, on this basis, adding meteorological features improved the prediction accuracy with smaller deviations, higher R2 (0.88), and smaller MAE and RMSE (0.06 and 0.08). 3) The model prediction was also affected by crop growing stages. The accuracy based on the meteorological features of winter wheat florets differentiation and heading and flowering stage was higher than the other spike differentiation periods, indicating that the environmental changes during this period have a greater impact on the final yield; The predicted results at the late drug interval had the larger deviation from the actual yield. It was because the meteorological factors had strong correlation and it weakened the impacts of spatial characteristics. 4) Based on the importance of outside the bag data, In the meteorological features, the average temperature and minimum temperature of winter wheat floret differentiation period, the spatial characteristics parameters were important. In addition, the negative accumulated temperature from the jointing to heading stage, and the maximum temperature at heading and flowering stage had great influence on yield. During the model establishment, we didn’t differentiate disaster from non-disaster year because the sample sizes were small. However, during the model validation, the data were from both normal and disaster years, which could ensure the reliability of the prediction model. Thus, the winter wheat yield prediction based on random forest should consider both spatial and meteorological characteristics parameters. The results of this study provide new ideas and methods for early prediction of winter wheat yield. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 33

Main heading: Weather forecasting

Controlled terms: Atmospheric temperature  -  Crops  -  Cultivation  -  Decision trees  -  Disasters  -  Mean square error  -  Meteorology  -  Models  -  Temperature  -  Time series

Uncontrolled terms: Accumulated temperatures  -  Characteristics parameters  -  Determination coefficients  -  Different growth stages  -  Random forests  -  Spatial characteristics  -  Winter wheat  -  Yield prediction

Classification code: 443 Meteorology  -  443.1 Atmospheric Properties  -  641.1 Thermodynamics  -  821.3 Agricultural Methods  -  821.4 Agricultural Products  -  922.2 Mathematical Statistics  -  961 Systems Science

DOI: 10.11975/j.issn.1002-6819.2019.06.019

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

10. Effect of temperature and particle size on thermophysical properties of different energy feedstuffs material

Accession number: 20192307005298

Title of translation:

Authors: Kong, Dandan (1); Fang, Peng (1); Jin, Nan (1); Duan, Enze (1); Chen, Jiyuan (1); Wang, Hongying (1)

Author affiliation: (1) National R&D Center for Agro-processing Equipment, College of Engineering, China Agricultural University, Beijing; 100083, China

Corresponding author: Wang, Hongying(hongyingw@cau.edu.cn)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 296-306

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Energy feedstuffs, the most important and indispensable components in the pelleted complete feeds, provide energy in the form of soluble carbohydrate, oil and fat. Energy feedstuffs mainly includes cereals, cereal brans, molasses, oil, tuber and tuberous root, among which corn, wheat, barley, sorghum, wheat/rice bran, pelleted cassava residue and beet pulp are widely utilized in diets for livestock and poultry. Knowledge of the thermal properties of different feedstuffs is required for designing and parameter optimization of thermal process such as conditioning and pelleting processing, especially when energy costs, pellet quality and uniformity are the main consideration. The specific heat, thermal conductivity and thermal diffusivity are the most important thermal properties. In this paper, eight energy feed ingredients (4 cereal grains: corn, wheat, barley, sorghum; 4 processed by-products: wheat bran, pelleted cassava residue, pelleted beet pulp, rice bran) were obtained from a feed mill in the suburb of Beijing, and ground in a mini-mill equipped with screens having a aperture size of 1.5, 2.0 or 2.5 mm to obtain feed meals with 3 particle sizes (except rice bran, which could pass through the 1.5 mm screen completely without being ground). The moisture content of all feed meal samples was conditioned to 12% wet basis in order to eliminate the effect of moisture content difference on thermal properties. The specific heat, thermal conductivity of feed meals at the temperature range of 25-100 were determined by DSC (differential scanning calorimetry) and KD2 Pro (thermal properties analyzer), respectively. Thermal diffusivity of feed meals was calculated using measured thermal conductivity, specific heat, and bulk density. Based on the experimental data, prediction models of three thermal properties as a function of temperature were established. The effects of particle size on thermal properties of feedstuffs were analyzed. The particle size of 8 feedstuffs grinding through screens with aperture size of 1.5, 2.0 and 2.5 mm ranged from 257.61 to 511.79 μm, 325.65 to 594.83 μm and 335.28 to 671.05 μm, respectively, which increased significantly with the increase in mesh size. There were significant differences between the values of particle size of 8 feedstuffs through the same mesh size. The values of specific heat of 4 grain meals (passing a screen with aperture size of 1.5 mm) increased with temperature (25-100) and ranged from 1.678 to 2.421, 1.644 to 2.402, 1.642 to 2.385, and 1.649 to 2.441 kJ/(kg•K), respectively. For wheat bran, cassava residue and beet pulp, the values were found to range from 1.621 to 2.540, 1.580 to 2.195, 1.746 to 2.351 kJ/(kg•K). The specific heat of rice bran raised from 1.966 kJ/(kg•K) at 25 to 1.985 kJ/(kg•K) at peak temperature (28.0), then declined to 1.868 kJ/(kg•K) at end-set temperature (33.5), and finally increased to 2.671 kJ/(kg•K) at 100. There was no significant effect of particle size on the specific heat of all feedstuffs (P>0.05). The specific heat followed linear relationships with temperature at the range of 25-100 for 4 grains, and cubic polynomial relationships for wheat bran, cassava residue and rice bran, and a second order polynomial relationship for beet pulp. The values of thermal conductivity of 4 grain meals (passing a 1.5 mm screen) increased nonlinearly with temperature (25-100) and varied from 0.089 to 0.299, 0.078 to 0.336, 0.088 to 0.276 and 0.082 to 0.288 W/(m•K), respectively. For 4 processed by-products, the thermal conductivity was found to raise from 0.054 to 0.190, 0.092 to 0.362, 0.085 to 0.263, and 0.064 to 0.202 W/(m•K), respectively. Significant differences were observed between the thermal conductivity of 8 feed mills (passing a 1.5 mm screen) at a higher temperature (85 or 100), and the thermal conductivity of cassava residue was the highest, followed by wheat, wheat bran with the lowest value. For the same feedstuffs, the thermal conductivity of feed mills, at the same temperature, decreased generally with the increase in particle size, and the higher temperature, the stronger decrease. Cubic polynomial relationships of thermal conductivity with temperature (25-100) were established for 4 grains and beet pulp with different particle sizes, and quadratic polynomial relationships were obtained for wheat bran, cassava residue and rice bran. The values of thermal diffusivity of 4 grain meals (passing a 1.5 mm screen) varied from 7.459×10-8 to 17.320×10-8, 6.694×10-8 to 19.195×10-8, 7.878×10-8 to 17.045×10-8, and 6.857×10-8 to 16.109 ×10-8 m2/s at temperature range of 25-100, respectively. The values was observed to ascend from 9.543×10-8 to 20.892×10-8, 8.217×10-8 to 23.254×10-8, 7.258×10-8 to 16.646×10-8 and 8.092×10-8 to 18.718 ×10-8 m2/s for 4 processed by-products, respectively. In general, the thermal diffusivity of the 8 energy feedstuffs had a slow increase with temperature at the range of 25-55, and a sharply raise with temperature at the range of 55-100. The thermal diffusivity of all 8 feedstuffs tended to decline with increasing particle size. The thermal diffusivity displayed second order polynomial relationship with temperature at the range of 25-100 for wheat bran and rice bran, and cubic polynomial relationships for the other 6 feedstuffs. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 40

Main heading: Thermal conductivity

Controlled terms: Cereal products  -  Differential scanning calorimetry  -  Diffusion  -  Feeding  -  Grain (agricultural product)  -  Mesh generation  -  Moisture  -  Moisture determination  -  Particle size  -  Pelletizing   -  Plants (botany)  -  Polynomials  -  Specific heat  -  Temperature  -  Thermal diffusivity

Uncontrolled terms: Different particle sizes  -  Dsc(differential scanning calorimetry)  -  Effect of temperature  -  Linear relationships  -  Parameter optimization  -  Quadratic polynomial  -  Second-order polynomial  -  Soluble carbohydrates

Classification code: 641 Heat and Mass Transfer; Thermodynamics  -  641.1 Thermodynamics  -  691.2 Materials Handling Methods  -  821.4 Agricultural Products  -  822.3 Food Products  -  921.1 Algebra  -  921.4 Combinatorial Mathematics, Includes Graph Theory, Set Theory  -  944.2 Moisture Measurements  -  944.6 Temperature Measurements

Numerical data indexing: Size 2.00e-03m, Size 2.50e-03m, Size 2.58e-04m to 5.12e-04m, Size 3.26e-04m to 5.95e-04m, Size 3.35e-04m to 6.71e-04m, Thermal_Conductivity 6.40e-02W/m*K to 2.02e-01W/m*K, Thermal_Conductivity 8.20e-02W/m*K to 2.88e-01W/m*K, Percentage 1.20e+01%, Size 1.50e-03m

DOI: 10.11975/j.issn.1002-6819.2019.06.036

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

11. Pore characteristics of straw interlayer based on computed tomography images and its influence on soil water infiltration

Accession number: 20192307005276

Title of translation: CT

Authors: Zhang, Hongyuan (1); Pang, Huancheng (1); Lu, Chuang (1); Liu, Na (1); Zhang, Xiaoli (1); Li, Yuyi (1)

Author affiliation: (1) Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing; 100081, China

Corresponding author: Li, Yuyi(liyuyi@caas.cn)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 114-122

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: In order to clarify mechanisms behind the influence of interlayer established by different physical forms of corn straw in saline-alkali soil on soil infiltration characteristics, the indoor simulation experiment method was adopted. A total of 4 treatments of different straw forms buried with the equal thickness of 5 cm at 40-45 cm under topsoil as an interlayer were designed, including no straw interlayer (CK), segmented straw with 5 cm length (SL), straw pellet (SK), and straw powder (SF). The computed tomography (CT) images were used to quantitatively analyze the pore parameters such as porosity and pore size distribution of the straw interlayer and its relationship with the infiltration rate of irrigation water. The results showed that compared to CK, the corn straw interlayer with different physical forms significantly increased the total porosity of the 40-45 cm layer, with SF as the highest, which was significantly higher than that of CK, SL and SK by 29.25, 12.09 and 12.61 percentage points (P 0.05). The porosity with pore diameter ≤ 1 mm in the SF treatment significantly increased at each stage of irrigation water infiltration (P 1 mm in the SL treatment was 1.04 percentage points higher than that of SK before infiltration, but that in the SK treatment was significantly higher than SL after infiltration. This transformation of macropores with pore diameter > 1 mm resulted that the wetting front of SK had taken longer time than SL through the straw layer, while the wetting front had taken less time than SL after passing through straw layer to the bottom of the soil column. Correlation analysis showed that there was a significant positive correlation between the time of wetting front through the straw layer and the total porosity, the porosity of pore diameter ≤ 1 mm before and after the infiltration, but there was a significant negative correlation with the porosity of pore diameter > 1 mm porosity before infiltration (P © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 36

Main heading: Infiltration

Controlled terms: Computerized tomography  -  Irrigation  -  Pore size  -  Pore structure  -  Saline water  -  Soil moisture  -  Straw  -  Wetting

Uncontrolled terms: Computed tomography images  -  Correlation analysis  -  Infiltration characteristic  -  Pore characteristics  -  Pores  -  Porosity and pore size  -  Positive correlations  -  Saline-alkali soils

Classification code: 444 Water Resources  -  483.1 Soils and Soil Mechanics  -  723.5 Computer Applications  -  821.3 Agricultural Methods  -  821.5 Agricultural Wastes  -  931.2 Physical Properties of Gases, Liquids and Solids

Numerical data indexing: Size 4.00e-01m to 4.50e-01m, Size 5.00e-02m, Size 1.00e-03m

DOI: 10.11975/j.issn.1002-6819.2019.06.014

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

12. Pig continuous cough sound recognition based on continuous speech recognition technology

Accession number: 20192307005283

Title of translation:

Authors: Li, Xuan (1, 2); Zhao, Jian (1, 2); Gao, Yun (1, 2); Liu, Wanghong (2, 3); Lei, Minggang (2, 3); Tan, Hequn (1, 2)

Author affiliation: (1) College of Engineering, Huazhong Agricultural University, Wuhan; 430070, China; (2) Cooperative Innovation Center for Sustainable Pig Production, Wuhan; 430070, China; (3) College of Animal Science and Technology, College of Animal Medicine, Huazhong Agricultural University, Wuhan; 430070, China

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 174-180

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Cough is one of the most frequent symptoms in the early stage of pig respiratory diseases. So it is possible to monitor and diagnose the diseases of pigs by detecting their coughs. The existing methods for pig cough recognition are based on key word recognition technology, which cannot recognize the samples that have not been trained or learned by itself, another drawback is that the methods are for isolated coughs while the coughs of sick pigs are usually continuous. This paper intends to realize the recognition of pig continuous cough sound based on continuous speech recognition technology. Ten Landrace pigs, with a body weight of about 75 kg, were used as sound collection objects, and pig sounds were collected in pig farms during late winter and early spring when the respiratory diseases of pigs were prevalent. The sound collection devices were working continuously all day. By selecting the frequent coughing phases in the collected signal, a total of 30 h pig farm sound signals were obtained as the experimental corpus. Firstly, the sound signals were denoised by the speech enhancement algorithm based on a psychoacoustical model. Then the time-domain characteristics, including duration and energy of individual cough, were studied, and it was found that the duration of pig cough ranged from 0.24 to 0.74 s and the energy ranged from 40.15 to 822.87 V2•s. So threshold of the sound samples was set with the duration and the lower energy value of individual coughs. Based on the threshold range, the speech endpoint detection algorithm based on short-time energy was used to detect the 30 h pig field sound signals which had been preprocessed by the speech enhancement algorithm, and 222 experimental sentences were obtained. The longest was 9.14 s and the shortest was 3.91 s. All 222 corpus contained a total of 1 145 sound samples, including 751 pig coughs and 394 non-pig coughs. Sounds in the pig farm environment, including cough, sneeze, eating, scream, hum, shaking ears sounds of pigs and sounds of dogs, metal clanging and some other background noise, were divided into pig cough and non-pig cough, which were chosen as the acoustic modeling units. The labels of the experimental sentences were obtained with the help of experts. Then the 13-dimensional Mel frequency cepstrum coefficients (MFCC) reflecting the static characteristics of pig sound were extracted, and the first-order differential coefficients reflecting the dynamic characteristics of pig sound were added to obtain the 26-dimensional MFCC, which were used as the characteristic parameter of the experimental sentence. Finally, the bidirectional Long Short-term Memory-Connectionist temporal classification(BLSTM-CTC) model was selected to recognize the pig continuous sounds, specifically, the BLSTM network had excellent feature learning ability of continuous pig sounds, and the CTC could directly model the alignment of the input continuous pig sound sequence and its labels. Through the 5-fold cross-validation experiment and analysis, the number of hidden layer neurons in the BLSTM forward propagation process, the backward propagation process, and the fully connected layer, were all set to 300, and the learning rate was set to 0.001. The average recognition rate, error recognition rate and total recognition rate of the results of 5 groups were 92.40%, 3.55% and 93.77%, respectively. Furthermore, the algorithm application test was carried out with another 1 h data, and the recognition rate reached to 94.23%, the error recognition rate was 9.09% with the total recognition rate of 93.24%. It is indicated that the pig cough sound recognition model based on continuous speech recognition technology is stable and reliable. This paper provides a reference for the recognition and disease judgment of pig continuous cough sound during the healthy breeding of pigs. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 33

Main heading: Mammals

Controlled terms: Brain  -  Continuous speech recognition  -  Long short-term memory  -  Pulmonary diseases  -  Signal processing  -  Speech enhancement  -  Temperature measurement  -  Time domain analysis

Uncontrolled terms: Acoustic model  -  Acoustic signals  -  Continuous cough  -  Pig industry  -  Recognition  -  Temporal classification

Classification code: 461.1 Biomedical Engineering  -  461.6 Medicine and Pharmacology  -  716.1 Information Theory and Signal Processing  -  751.5 Speech  -  921 Mathematics  -  944.6 Temperature Measurements

Numerical data indexing: Mass 7.50e+01kg, Percentage 3.55e+00%, Percentage 9.09e+00%, Percentage 9.24e+01%, Percentage 9.32e+01%, Percentage 9.38e+01%, Percentage 9.42e+01%, Time 1.08e+05s, Time 2.40e-01s to 7.40e-01s, Time 3.60e+03s, Time 3.91e+00s, Time 9.14e+00s

DOI: 10.11975/j.issn.1002-6819.2019.06.021

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

13. Design of screw-pneumatic coupling conveying device for crushed corn straw

Accession number: 20192307005266

Title of translation: -

Authors: Wulantuya (1); Qing, Lin (1); Wang, Chunguang (1)

Author affiliation: (1) College of Mechanical and Electrical Engineering of Inner Mongolia Agricultural University, Hohhot; 010018, China

Corresponding author: Wang, Chunguang(jdwcg@imau.edu.cn)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 29-38

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: The main ways of crushed corn straw conveying are pneumatic conveying, screw conveying, belt conveying, scraper conveying, bucket lifting and chain conveying. Screw conveyor is widely used in the processing of rubbing and breaking corn straw due to its advantages of compact structure, flexible arrangement, good sealing and controllable feeding amount. However, due to the small density, viscosity and poor fluidity of crushed corn straw, the conveying performance is difficult to be guaranteed. There are some problems such as low productivity, high power consumption, easy jammed and serious abrasion in the process of conveying the agricultural fiber materials. In order to solve these problems, the theoretical analysis of conveying process about screw-pneumatic conveying device was carried out in this paper. The force of crushed corn straw during the conveying was analyzed. On this basis, the productivity model, power consumption model and specific power consumption were built. The screw flow transmission principle was considered, and the screw-pneumatic coupling conveying device was designed. The experimental platform was mainly composed of screw conveying device and pneumatic auxiliary conveying system. The parameters of the experimental platform were as follows: the conveying gap length was 2 500 mm, the diameter of the screw blade was 250 mm, the diameter of the center shaft was 60 mm, the screw pitch was 335 mm respectively, and the space between the screw blade and the shell was 5 to 8 mm. The pneumatic auxiliary conveying system was mainly composed of Y-shape nozzle holder with adjustable injection angle, nozzle, air compressor with maximum outlet pressure of 1.6 MPa, polypropylene random straight pipe with 10 mm diameter, 15° bending pipe and pressure gauge. The experiment materials were the corn straw after crushing through 9R-60 rubber and with less than 100 mm long, 2 to 8 mm wide, and 38% moisture content. Based on the performance index of specific power consumption, axial thrust, pressure on the screw blade and shell, the impacts of airflow velocity on transportation performance were analysed. The results showed that: When the screw pitch was 335 mm, the rotation speed was 100 r/min, and the feeding amount was 70 kg/min, within the range of airflow velocity 10~50 m/s, the greater the pressure on the outer edge, the greater the pressure on the screw blade. the pressure was different at different points of screw blade, the closer to the outlet, the greater the pressure was on all parts of the blade. On the same area of the shell, the pressure on the arc segment was greater than that of the vertical section. For different area of the shell, the pressure on the arc segment and vertical section of areawas greater than that of the area. The pressure was different at different points of shell, the closer to the outlet, the greater the pressure was on all parts of the shell. The specific power consumption of the screw-pneumatic coupling conveying device first decreased and then increased with the increase of airflow velocity, when the airflow velocity was 20 m/s, the specific power consumption was the minimum, which was 10.78 W/kg, which was 8.3% lower than that of without airflow. The axial thrust, pressure on blade and shell decreased with the increase of airflow velocity, and was all less than that of without airflow. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 28

Main heading: Screws

Controlled terms: Agricultural machinery  -  Agriculture  -  Air  -  Belt conveyors  -  Chain conveyors  -  Conveying  -  Design  -  Electric power utilization  -  Gas compressors  -  Machine design   -  Nozzles  -  Pneumatic conveyors  -  Pneumatics  -  Polypropylenes  -  Productivity  -  Shells (structures)  -  Straw  -  Velocity

Uncontrolled terms: Agricultural fibers  -  Experimental platform  -  Flow transmissions  -  High power consumption  -  Performance indices  -  Pneumatic conveying  -  Power consumption model  -  Specific power consumption

Classification code: 408.2 Structural Members and Shapes  -  601 Mechanical Design  -  605 Small Tools and Hardware  -  618.1 Compressors  -  632.3 Pneumatics  -  692.1 Conveyors  -  706.1 Electric Power Systems  -  804 Chemical Products Generally  -  815.1.1 Organic Polymers  -  821 Agricultural Equipment and Methods; Vegetation and Pest Control

Numerical data indexing: Mass_Flow_Rate 1.17e+00kg/s, Percentage 3.80e+01%, Percentage 8.30e+00%, Pressure 1.60e+06Pa, Rotational_Speed 1.00e+02RPM, Size 1.00e-01m, Size 1.00e-02m, Size 2.00e-03m to 8.00e-03m, Size 2.50e+00m, Size 2.50e-01m, Size 3.35e-01m, Size 5.00e-03m to 8.00e-03m, Size 6.00e-02m, Velocity 1.00e+01m/s to 5.00e+01m/s, Velocity 2.00e+01m/s

DOI: 10.11975/j.issn.1002-6819.2019.06.004

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

14. Design and no-load performance test of GU-PCM2 temperature controlled phase change storage refrigerator

Accession number: 20192307005297

Title of translation: GU-PCM2

Authors: Liu, Guanghai (1); Wu, Junzhang (1); Foster, Alan (2); Xie, Ruhe (1); Tang, Haiyang (1); Zou, Yifeng (1); Qu, Ruigui (3, 4)

Author affiliation: (1) Research Center for Cold Chain & Standardization, Guangzhou University, Guangzhou; 510006, China; (2) School of Engineering, London South Bank University, Bristol; BS40 5DU, United Kingdom; (3) Guangzhou City Polytechnic, Guangzhou; 510405, China; (4) School of Traffic and Transportation Engineering, Central South University, Changsha; 410075, China

Corresponding author: Qu, Ruigui(64855316@qq.com)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 288-295

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: The existing phase change material (PCM) devices of PCM refrigerated truck are mostly arranged on the top of the carriage, which has the problems of high gravity center and uncontrollable temperature and so on. In view of the above problems, a new type refrigerated truck was designed in this paper, which integrated phase change thermal storage unit, refrigeration system, heat-insulated carriage, air supply system and so on. The cold storage device was set independently in the front of the truck and was insulated. PCM mass required for phase change thermal storage unit was 360 kg (the phase transition temperature is -30 and the latent heat of phase change is 175.3 kJ/kg), which used cheap electricity at night to store energy, when working, the temperature in carriage could be adjusted between -25-10. The simulation and tests of 2 working modes were carried out with the setting temperature of 0 and -18 in a refrigerated prototype. A computational fluid dynamics (CFD) simulation model of PCM refrigerated truck was built and the temperature field in carriage was simulated, the root mean square error and maximum absolute error between simulations and measurements of 2 working modes were 0.7 and 0.8, 1.1 and 1.2 respectively, the simulated temperature calculated by the simulation model agreed well with the measured temperature, and the measured temperature near the air outlet in the carriage was slightly lower than the simulation temperature, while the measured temperature near the rear section was slightly higher than the simulation temperature, this was due to the fact that the simulation data were generally in an ideal state, but the cold leak was unavoidable at the return air outlet of the actual refrigerated truck and the heat leak (air leak) at the door. The test results showed that the new type of PCM refrigerated truck proposed in this paper could effectively control the temperature more than 10 h on the basis of sufficient cold storage. The average temperature fluctuated between 1.1-2.9 and -14.8--16.9 and the fluctuation ranges were 1.8 and 2.1 under the 2 working modes. The lowest temperature in the carriage was located at the front of the carriage and close to both sides of the air outlet, the high temperature area was located at the top of the middle of the carriage and near the air inlet. The coefficient of temperature non-uniformity was less than 1.0 when the setting temperature in carriage was 0 and was less than 0.4 when the setting temperature in carriage was -18. In terms of cooling time, it took 60 minutes when the carriage was set to 0 and 90 minutes when the carriage was set to -18. The tested results showed that the average temperature fluctuation of the new type temperature controlled PCM refrigerated truck was 48.7% lower than that of the traditional PCM refrigeration truck, the coefficient of temperature non-uniformity was 50% lower, and the center of gravity was 25.9% lower than that of the overhead traditional PCM refrigeration truck. In addition, the temperature stability of the new type PCM refrigerated truck was better than that of the similar mechanical refrigerated truck because it didn’t need to defrost the evaporator during long-term operation. The new type PCM refrigerated truck can effectively reduce the transportation energy consumption and cost while guaranteeing the quality and safety of goods, and the research provided the basis for the optimization and application of the PCM refrigerated truck. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 31

Main heading: Trucks

Controlled terms: Air  -  Automobile testing  -  Cold storage  -  Cold working  -  Computational fluid dynamics  -  Design  -  Energy utilization  -  Experiments  -  Heat storage  -  Mean square error   -  Numerical analysis  -  Phase change materials  -  Refrigeration  -  Temperature  -  Temperature control  -  Truck transportation  -  Virtual storage

Uncontrolled terms: Computational fluid dynamics simulations  -  Distribution of temperature  -  Phase Change  -  Phase-change thermal storages  -  Root mean square errors  -  Simulations and measurements  -  Temperature fluctuation  -  Transportation energy consumption

Classification code: 432.3 Cargo Highway Transportation  -  525.3 Energy Utilization  -  535.2 Metal Forming  -  641.1 Thermodynamics  -  644.1 Refrigeration Methods  -  644.3 Refrigeration Equipment and Components  -  662 Automobiles and Smaller Vehicles  -  663.1 Heavy Duty Motor Vehicles  -  722.1 Data Storage, Equipment and Techniques  -  723.5 Computer Applications  -  731.3 Specific Variables Control  -  804 Chemical Products Generally  -  901.3 Engineering Research  -  921.6 Numerical Methods  -  922.2 Mathematical Statistics

Numerical data indexing: Time 3.60e+04s, Time 5.40e+03s, Mass 3.60e+02kg, Percentage 2.59e+01%, Percentage 4.87e+01%, Percentage 5.00e+01%, Specific_Energy 1.75e+05J/kg, Time 3.60e+03s

DOI: 10.11975/j.issn.1002-6819.2019.06.035

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

15. Layout optimization of soil moisture sensor in tea plantation based on affinity propagation clustering algorithm

Accession number: 20192307005275

Title of translation:

Authors: Zhang, Wu (1); Zhang, Manman (1); Hong, Xun (1); Jiang, Zhaohui (1); Jiang, Yuelin (2)

Author affiliation: (1) School of Information & Computer, Anhui Agricultural University, Hefei; 230036, China; (2) School of Resources and Environment, Anhui Agricultural University, Hefei; 230036, China

Corresponding author: Jiang, Zhaohui(jiangzh@ahau.edu.cn)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 107-113

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Aiming at the layout problem of soil moisture sensors for water-saving irrigation, we proposed an optimal layout strategy of soil moisture sensors based on affinity propagation (AP) clustering algorithm. The soil moisture of tea plantation was as the research object. The tea plantation had 84-m width and 190-m length. Following the conventional method, 25 sensor nodes were evenly arranged in rectangular mode in tea plantation experimental area in order to guarantee full coverage of tea plantation sensor network. Soil moisture data of each sensor node in the test area was collected in real time for 3 days. The optimization of sensors was conducted based on soil water content and relative water content by AP clustering algorithm. Different clustering parameters were selected. The AP clustering algorithm was used to construct similarity matrix of node soil water content, to iteratively calculate the responsibility and availability of each node, and to form the clustering number and clustering center. When the clustering parameters were 10, 15, 20 and 25 times of preference, the AP clustering algorithm was used to calculate the soil moisture data in the experimental area for 3 days, the stable and consistent clustering results were obtained. Results showed that soil water content in the tested plantation presented an increasing trend from southwest to northeast and the largest difference of relative water content was 15%. The change is related to the topography of the tested area. For AP clustering, the maximum iterative times was designed as 1 000. Based on the results, the clustering result in the 3 days was 2. The number of sensors optimized by AP clustering algorithm was reduced from 25 to 2. The class mean of the relative water content of the soil in the experimental area was calculated, and compared with the relative water content of soil in the collection points of the cluster center, and the relative bias between them was less than 5%. The relative water content of the collection points in the cluster center was close to the average value of the experimental area, which indicated that the data collected by the cluster center can represent soil moisture situation in the experimental tea plantation. In order to verify the validity of this method, soil moisture data were collected randomly at 13 locations in the experimental area on January 2019. Results showed that the soil average relative water content of tea plantation in the experimental area based on 13 sampling points was 32.7%, the relative water content of soil in the cluster center based on 2 sensors was respectively 27.9% and 37% with an average in the cluster center of 32.45%. Compared with the average relative moisture in the experimental area, the relative bias was only 0.76%. It means that the AP clustering algorithm can optimize the distribution of soil moisture sensors in the experimental tea plantation. The relative soil moisture collected by the cluster center could reflect the overall situation of soil moisture in the tea plantation as long as using only 2 sensors arranged in the cluster center node determined by the optimization calculation. Thus, the AP clustering algorithm is suggested to use in optimization of the sensor layout, which can reduce the redundancy of data and accordingly realize cost saving in agricultural production system. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 31

Main heading: Clustering algorithms

Controlled terms: Agriculture  -  Iterative methods  -  Moisture control  -  Moisture meters  -  Sensor networks  -  Sensor nodes  -  Sensors  -  Soil moisture  -  Soil surveys  -  Topography   -  Water conservation  -  Water content

Uncontrolled terms: Affinity propagation clustering  -  Agricultural production system  -  Layout optimization  -  Optimization calculation  -  Relative soil moistures  -  Relative water content  -  Soil moisture sensors  -  Water-saving irrigation

Classification code: 444 Water Resources  -  483.1 Soils and Soil Mechanics  -  722 Computer Systems and Equipment  -  821 Agricultural Equipment and Methods; Vegetation and Pest Control  -  903.1 Information Sources and Analysis  -  921.6 Numerical Methods  -  944.1 Moisture Measuring Instruments  -  944.2 Moisture Measurements  -  951 Materials Science

Numerical data indexing: Age 8.22e-03yr, Percentage 1.50e+01%, Percentage 2.79e+01%, Percentage 3.25e+01%, Percentage 3.27e+01%, Percentage 3.70e+01%, Percentage 5.00e+00%, Percentage 7.60e-01%, Size 1.90e+02m, Size 8.40e+01m

DOI: 10.11975/j.issn.1002-6819.2019.06.013

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

16. Establishment and optimization of comprehensive evaluation model for seed and seed oil traits of Handeliodendron bodinieri

Accession number: 20192307005300

Title of translation:

Authors: Guo, Song (1, 2); Li, Zailiu (2); Xue, Jianhui (1, 3)

Author affiliation: (1) Jiangsu Key Laboratory of Forestry Ecological Engineering, Nanjing Forestry University, Nanjing; 210037, China; (2) College of Forestry, Guangxi University, Nanning; 530004, China; (3) Institute of Botany Jiangsu Province and Chinese Academy of Sciences, Nanjing; 210014, China

Corresponding author: Xue, Jianhui(jhxue@njfu.com.cn)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 314-322

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Handeliodendron bodinieri was a rare and endangered endemic single species genus plant only in karst areas of southwestern China, and it was also an excellent species of rocky desertification control, furthermore, its seed oil had higher value in nutrition, health care and industry. However, due to the lack of recognition of the related traits of H. bodinieri germplasm resources, the planting and popularization of H. bodinieri was restricted to some extent. Therefore, it was necessary to scientifically evaluate seed and seed oil traits of H. bodinieri from different provenances in order to guide the selection of good provenance and breeding. To improve the accuracy of evaluation results and optimum selection evaluation method, a new comprehensive evaluation model was constructed in this study. Fourteen indices related to seed and seed oil of H. bodinieri including seed length, seed diameter, single seed weight, 1 000- grain weight of seed, seed kernel rate, seed oil content, unsaturated fatty acid compositions of seed oil and so on were selected and determined. Five provenances of Leye of Guangxi, Tianlin of Guangxi, Fengshan of Guangxi, Huanjiang of Guangxi and Dushan of Guizhou were evaluated and sorted by four single evaluation methods of principal component analysis, factor analysis, maximizing deviation method, entropy weight method. The evaluation results of four single methods above were evaluated and sorted by three combination evaluation methods of mean, Borda and Copeland. Final evaluation rank was determined after all these methods had passed the Kendall’s coefficient of concordance test. Spearman rank correlation coefficient was used to analyze the correlation between the final evaluation rank and four single methods evaluation ranking, and the best single evaluation method was selected at last. The results are showed following: Although there are some differences in the ranking of provenance evaluation in four single evaluation methods, they have passed the Kendall’s coefficient of concordance test; all the three combination methods evaluation rank values are the same. Final evaluation ranking of provenance from high to low is Fengshan of Guangxi, Leye of Guangxi, Dushan of Guizhou, Huanjiang of Guangxi and Tianlin of Guangxi. Spearman rank correlation coefficient between final evaluation ranking and evaluation ranking of principal component analysis, factor analysis, maximum deviation method and entropy weight method are 1.00, 0.90, 1.00 and 0.90 respectively, and all correlations have reached a significant level (P © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 42

Main heading: Oils and fats

Controlled terms: Conservation  -  Entropy  -  Factor analysis  -  Multivariant analysis  -  Oil fields  -  Principal component analysis  -  Seed  -  Unsaturated fatty acids

Uncontrolled terms: Combination evaluation  -  Comprehensive evaluation  -  Comprehensive evaluation model  -  Handeliodendron bodinieri  -  Kendall’s coefficient of concordance  -  Rocky desertification controls  -  Seed oil  -  Spearman rank correlation

Classification code: 512.1.1 Oil Fields  -  641.1 Thermodynamics  -  804.1 Organic Compounds  -  821.4 Agricultural Products  -  922 Statistical Methods  -  922.2 Mathematical Statistics

DOI: 10.11975/j.issn.1002-6819.2019.06.038

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

17. Measurement of shear strength and its change in unsaturated soils modified by hydrophobic agent

Accession number: 20192307005277

Title of translation:

Authors: Wu, Junhua (1); Lin, Hui (1); Zhou, Xiaoyu (1); Deng, Yichao (1); Yang, Song (2)

Author affiliation: (1) College of Civil Engineering and Architecture, Nanchang Hangkong University, Nanchang; 330063, China; (2) College of Water Conservancy, Yunnan Agricultural University, Kunming; 650201, China

Corresponding author: Yang, Song(yscliff007@126.com)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 123-129

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: In order to study how shear strength and its change in unsaturated soils modified by hydrophobic agent, sandy soils hydrophobized by dimethyldichlorosilane (DMDCS) were prepared. The hydrophobic soils with different DMDCS volume by soil mass, water content and clay content were obtained respectively. Mixtures of sandy soils (DMDCS volume by soil mass were 2 mL:100 g and 3 mL:100 g, i.e., 2% and 3%, the same below) with 3%, 5%, 7%, 11% and 13% water content were prepared respectively. Meanwhile, the mixtures of clay and sandy soils (3% DMDCS) according to the clay mass fraction of 0, 5%, 10%, 15%, 20%, 25%, 30%, 40% and 50% were prepared respectively. Then the unsaturated direct shear tests were carried out by unsaturated direct shear apparatus. Four samples in each group were prepared under the normal pressure in 100, 200, 300 and 400 kPa, respectively. The horizontal shearing ratio was 0.8 mm/min and the shearing test lasted 6 min. The results showed that: 1) The mixtures of sandy soils and DMDCS presented extreme hydrophobicity. 2) The water repelling of mixtures of clay and sandy soils was affected by both DMDCS and clay content. The water repelling of mixtures was degraded with the increasing of clay content, and improved with the increasing of DMDCS volume by soil mass. 3) The Mohr-Coulomb strength criterion could be adopted to describe the shear strength of hydrophobic sandy soils with different DMDCS and water content. With the increasing of DMDCS volume by soil mass, the shear strength index of the hydrophobic soil was decreased to different extents. The cohesive force showed a steep-drop shape from soil without DMDCS addition to that with 1% DMDCS and a slow decline up to stabilize finally. The effect of DMDCS on the cohesive force of modified sandy soils was much greater than on the internal friction angle. The hydrophobic soils’ cohesion with the increasing of water content was decreased gradually, while the internal friction angle was increased firstly and decreased finally. The water content had a much effect on the shear strength of the hydrophobic sandy soils. The shear strength index were decreased with the increasing of DMDCS volume by soil mass: the cohesion was declined rapidly from 19.6 kPa (no DMDCS) to 10.4 kPa (1% DMDCS) and slowly from 10.4 kPa (1% DMDCS) to 9.3 kPa (3% DMDCS). The internal friction angle was declined slowly from 16.2° (no DMDCS) to 11.8° (3% DMDCS). The cohesion was decreased with the increasing of water content: the cohesion was declined from 15.5 kPa (3% water content) to 7.5 kPa (13% water content) with 2% DMDCS and from 15 kPa (3% water content) to 5.2 kPa (13% water content) with 3% DMDCS respectively; the internal friction angle was increased from 12.7° (3% water content) to 15.2° (11% water content) with 2% DMDCS and from 11.7° (3% water content) to 14.6° (7% water content) with 3% DMDCS, then decreased to 13.9° (13% water content) with 2% DMDCS and 11.9° (13% water content) with 3% DMDCS respectively. 4) The Mohr-Coulomb strength criterion could also be adopted to describe the shear strength of hydrophobic mixed soils with different clay content. The cohesion was increased remarkably with the increasing of clay content. The cohesion of sandy soils without clay was 9.3 kPa, then suddenly increased to 27.2 kPa and 55.1 kPa mixed with 5% and 50% clay mass fraction, respectively. The internal friction angle was increased from 12.1° (5% clay mass fraction) to 16.2° (15% clay mass fraction), and then decreased to 9.7° (50% clay mass fraction). All the analysis could be beneficial to analyze the shear strength of hydrophobized soils and apply in engineering. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 44

Main heading: Shear strength

Controlled terms: Hydrophobicity  -  Internal friction  -  Mixtures  -  Sand  -  Shear flow  -  Shearing  -  Shearing machines  -  Soils  -  Water content

Uncontrolled terms: Dimethyldichlorosilane  -  Direct shear apparatus  -  Direct shear test  -  Hydrophobized  -  Internal friction angle  -  Mohr-Coulomb strength criterion  -  Shear strength indexes  -  Unsaturated soil

Classification code: 483.1 Soils and Soil Mechanics  -  603.1 Machine Tools, General  -  604.1 Metal Cutting  -  631.1 Fluid Flow, General  -  931.2 Physical Properties of Gases, Liquids and Solids

Numerical data indexing: Mass 1.00e-01kg, Percentage 1.00e+00%, Percentage 1.00e+01%, Percentage 1.10e+01%, Percentage 1.30e+01%, Percentage 1.50e+01%, Percentage 2.00e+00%, Percentage 2.00e+01%, Percentage 2.50e+01%, Percentage 3.00e+00%, Percentage 3.00e+01%, Percentage 4.00e+01%, Percentage 5.00e+00%, Percentage 5.00e+01%, Percentage 7.00e+00%, Pressure 2.72e+04Pa, Pressure 3.00e+05Pa, Pressure 4.00e+05Pa, Pressure 5.51e+04Pa, Pressure 9.30e+03Pa, Time 3.60e+02s

DOI: 10.11975/j.issn.1002-6819.2019.06.015

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

18. Endmember extraction of farmland hyperspectral image using deep learning autoencoder and shuffled frog leaping algorithm

Accession number: 20192307005282

Title of translation:

Authors: Han, Liqin (1, 2); Zhang, Yaonan (1); Qin, Qiming (3)

Author affiliation: (1) Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou; 730000, China; (2) University of Chinese Academy of Sciences, Beijing; 100049, China; (3) School of Earth and Space Sciences, Peking University, Beijing; 100871, China

Corresponding author: Zhang, Yaonan(yaonan@lzb.ac.cn)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 167-173

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Hyperspectral remote sensing image includes hundreds of narrow contiguous spectral bands with high spectral resolution, and can provides a contiguous spectral curve for each pixel, which is an important tool for the cropland monitoring in rapid and large-scale way. However, due to the contradiction between spectral resolution and spatial resolution, hyperspectral remote sensing image usually possesses relative low spatial resolution. Therefore, it is very important to mix various vegetation and soil at one pixel point for spectral decomposition in hyperspectral image and spectral unmixing of farmland. The first step in spectral unmixing is usually endmember extraction. Endmember extraction from a hyperspectral remote sensing image is to find some pixels (endmembers) and regard them as pure spectral reflectance of the vegetation and soil in the image to get the best accuracy of spectral unmixing results. So endmember extraction from hyperspectral remote sensing image can be regarded as a typical discrete optimization problem, which can be solved by swarm intelligence optimization algorithm. Before optimization, the spectral dimension of the image should be reduced by deep learning. In order to solve the problem of spectral unmixing of hyperspectral images, a method of extracting farmland endmember based on deep learning and shuffled frog leaping algorithm (SFLA) is proposed in this paper. Firstly, deep learning model named stacked auto encoders (SAE) was used to extract spectral features. SAE performs a non-linear transfer from the original spectral signals to a form with significant features and less dimensions. In the low-dimension space, the candidate endmembers were selected as the input of the SFLA. The purpose of extracting the candidate endmembers is to simplified the computational complexity in the next step. Secondly, the endmember extraction of hyperspectral image was transferred into the combinatorial optimization and the objective function was constructed, then the SFLA was used to optimize the objective functionto get the best combination of endmembers. The objective function in study was designed as the RMSE (root mean square error) between the real hyperspectral remote sensing image and the simulated hyperspectral remote sensing image using the endmembers and abundance after endmember extraction and spectral unmixing. Thirdly, 2 groups experiments were carried out on the synthetic hyperspectral datasets with 3 different SNR (signal to noise ratio, 20, 30 and 40 dB) and the real AVIRIS hyperspectral remote sensing dataset in Salinas region, respectively. In experiments, the experimental results of the proposed method was compared with that of 3 traditional methods for endmember extraction including the sequential maximum angle convex cone (SMACC), N-FINDR, Vertex Component Analysis (VCA). The results were evaluated by RMSE and spectral angle. The results showed that the RMSE was 0.050 8, 0.015 9, 0.005 1, 0.006 7 for 20, 30 and 40 dB dataset, and the real dataset, respectively. The average spectral angle was 0.106 88, 0.030 32, 0.009 94 for 20, 30 and 40 dB dataset respectively. The proposed method was better than traditional methods in terms of extraction accuracy, which had wide potential applications on cropland monitoring using hyperspectral remote sensing. The method proposed in this paper reduced the influence of the non-linear factors and the noise, better endmember extraction and spectral unmixing results (both less spectral angle and less RMSE) could be obtained, and the proposed method was robust when the noise of the image increased sharply. In conclusion, the endmember extraction method proposed by this study is of significant importance for the cropland monitoring using hyperspectral remote sensing and has a prosperous future for the application on the remote sensing of agriculture. © 2019, 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: Combinatorial optimization  -  Cones  -  Crops  -  Deep learning  -  Extraction  -  Farms  -  Image processing  -  Image resolution  -  Learning algorithms  -  Mean square error   -  Optimization  -  Pixels  -  Signal to noise ratio  -  Space optics  -  Spectral resolution  -  Spectroscopy  -  Vegetation

Uncontrolled terms: Autoencoders  -  Discrete optimization problems  -  Endmember extraction  -  HyperSpectral  -  Hyperspectral Remote Sensing Image  -  RMSE (root mean square error)  -  Shuffled frog leaping algorithm (SFLA)  -  Swarm intelligence optimization algorithm

Classification code: 716.1 Information Theory and Signal Processing  -  741.1 Light/Optics  -  802.3 Chemical Operations  -  821 Agricultural Equipment and Methods; Vegetation and Pest Control  -  821.4 Agricultural Products  -  921.5 Optimization Techniques  -  922.2 Mathematical Statistics

Numerical data indexing: Decibel 3.00e+01dB, Decibel 4.00e+01dB

DOI: 10.11975/j.issn.1002-6819.2019.06.020

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

19. Calibration of parameters of interaction between clayey black soil with different moisture content and soil-engaging component in northeast China

Accession number: 20192307005278

Title of translation:

Authors: Li, Junwei (1, 2, 3, 4); Tong, Jin (1, 3); Hu, Bin (2, 4); Wang, Hubiao (1, 3); Mao, Chunyu (1, 3, 5); Ma, Yunhai (1, 3)

Author affiliation: (1) Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun; 130022, China; (2) College of Mechanical and Electrical Engineering, Shihezi University, Shihezi; 832003, China; (3) College of Biological and Agricultural Engineering, Jilin University, Changchun; 130022, China; (4) Key Laboratory of Northwest Agricultural Equipment, Ministry of Agriculture, Shihezi University, Shihezi; 832003, China; (5) Jilin Engineering Normal University, Changchun; 130022, China

Corresponding author: Ma, Yunhai(myh@jlu.edu.cn)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 130-140

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: In order to obtain the interaction parameters which can be used for discrete element simulation between the soil-engaging components and clayey black soil in northeast China, the Hertz-Mindlin with JKR Cohesion contact model in EDEM2.7 was used to simulate the clayey black soil. Aiming at the actual working environment with moisture content of 10%-20%, 2 kinds of clayey black soil with moisture content of 12.46%±1% and 17.15%±1% were prepared respectively. The rolling friction coefficient, recovery coefficient, JKR surface energy parameter and the static friction coefficient between the soil particles were used as the model calibrated parameters. The soil repose angle simulated under the simulation parameters was set as the response value. The regression model of the soil repose angle was established based on the Box-Behnken response surface method, and the regression model was optimized by using the soil repose angles under 2 moisture contents obtained by physical experiments. The optimal solution of the contact model parameters of the clayey black soil particles with 2 moisture contents was obtained. The parameter range of the discrete element contact model of clayey black soil with moisture content between 10%-20% were given. The soil repose angle and stacked shape obtained by the simulation experiment with the optimized solution had a high similarity with that of the physical test. At the same time, the static friction coefficients of 3 kinds of soil contact materials such as 65Mn plate, UHMW-PE plate and PTFE plate were tested under the conditions of 4 kinds of moisture content, which were 0, 12.46%, 17.15% and 23.5% respectively. Then for the 2 typical soil contact materials such as 65Mn and PTFE, the slope physical test bench were constructed for the clayey black soil with moisture content of 17.15%±1%. The slope simulation models of 65Mn and PTFE materials were established under the EDEM2.7 software platform. Based on the critical simulation parameters such as JKR surface energy parameter, static friction coefficient, rolling friction coefficient and recovery coefficient between soil particle and soil contact material, the simulated rolling distance of the soil ball on different soil contact materials was set as the response value. The excellent fit regression model of rolling distance for the 2 kinds of typical soil contact materials were established based on the response surface optimization method of Box-Behnkende. The 2 regression models were optimized by the sliding distance obtained by the physical experiment. Then the optimized solution of the contact model parameters of different materials was obtained. The simulation results showed that when the surface energy of JKR between soil and 65Mn was 5.5 J/m2, the recovery coefficient was 0.61, the static friction coefficient was 0.57 and the rolling friction coefficient was 0.056, the rolling distance simulation result was 153.56 mm, which was close to the average rolling distance obtained from physical experiments of 155.93 mm, and the relative error was 1.52%; When the surface energy of JKR between soil and PTFE was 4.08 J/m2, the recovery coefficient was 0.6, the static friction coefficient was 0.52 and the rolling friction coefficient was 0.045, the simulation result of rolling distance was 269.35 mm, which was close to the average rolling distance of 269.55 mm obtained from physical experiment, and the relative error was 0.07%. And the optimized parameters can be used to simulate the discrete parameters between the clayey black soil and the soil-engaging components. The study provides credible basic data for the design and simulation of agricultural machinery under clayey black soil conditions. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 30

Main heading: Soils

Controlled terms: Calibration  -  Computer software  -  Electric contacts  -  End effectors  -  Finite difference method  -  Interfacial energy  -  Machine design  -  Moisture  -  Moisture determination  -  Recovery   -  Regression analysis  -  Simulation platform  -  Stiction  -  Surface properties  -  Water content

Uncontrolled terms: Black soil  -  Different moisture contents  -  Discrete element simulation  -  Response surface optimization  -  Simulation parameters  -  Soil-engaging components  -  Static friction coefficient  -  Surface energy parameters

Classification code: 483.1 Soils and Soil Mechanics  -  601 Mechanical Design  -  704.1 Electric Components  -  723 Computer Software, Data Handling and Applications  -  731.5 Robotics  -  921.6 Numerical Methods  -  922.2 Mathematical Statistics  -  944.2 Moisture Measurements  -  951 Materials Science

Numerical data indexing: Percentage 1.00e+01% to 2.00e+01%, Percentage 1.25e+01%, Percentage 1.71e+01%, Percentage 2.35e+01%, Percentage 7.00e-02%, Size 1.54e-01m, Size 1.56e-01m, Size 2.69e-01m, Size 2.70e-01m

DOI: 10.11975/j.issn.1002-6819.2019.06.016

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

20. Spatial-temporal variations and driving factor analysis of paddy fields in typical regions of Sanjiang Plain

Accession number: 20192307005292

Title of translation:

Authors: Zhang, Wenqi (1); Song, Ge (1)

Author affiliation: (1) Institute of Land Management, Northeast University, Shenyang; 110169, China

Corresponding author: Song, Ge(songgelaoshi@163.com)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 244-252

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Over the last three decades, paddy fields on the Sanjiang Plain have experienced rapid expansion. It has an important impact on regional food security, ecological environment and socio-economic development. Fujin is a typical area of Sanjiang Plain, with both common agricultural area and reclamation area, and the land use pattern is the epitome of Sanjiang Plain. In our study, used 1 000 m×1 000 m grid cell to scientifically analyze the spatial-temporal variation and driving factors of paddy fields, in Fujin from 1989 to 2002 and from 2002 to 2015. And elevation, slope, soil type, distance to railway, distance to river, distance to town and policy factors were selected as driving factors in this paper. With the help of GeoDetector, we analyzed the role of these seven factors in paddy field change and their relationship. The results indicated that such paddy fields have increased by approximately 349 900 hm2 from 1989 to 2015, and the paddy field process of reclamation area was earlier than that of common agricultural area. In the early 1990s, in order to adjust the agricultural planting structure, the local government began to encourage farmers to plant paddy rice in large areas. During this period, paddy rice planting area increased rapidly. From 1989 to 2002, the areas with the high proportion of paddy field expansion were mainly located in the reclamation areas in the northeast and southeast of Fujin County, and some other agricultural areas. From 2002 to 2015, the project of cultivated land development and improvement was implemented, and the cultivated land in Fujin reached a high level of agricultural development, and all the conditional areas were basically converted to paddy fields. The areas with higher proportion of paddy field expansion were mainly located in the southwestern common agricultural area and the northern reclamation area of Fujin City. In addition, the main driving factors of paddy field expansion in 1989-2002 were policy factors and soil types. The interaction between these factors was mostly enhanced by two factors. It showed that in the 1990s, under the guidance of the policy of agricultural structure adjustment, Fujin took the lead in reforming the soil types suitable for paddy fields and the land with superior location conditions. As a result, a large number of cultivated land resources with superior development conditions in the eastern reclamation area of Fujin were reclaimed into paddy fields. From 2002 to 2015, the influence of natural factors on paddy field change becomes weaker. The main driving factors of paddy field expansion are the distance from rivers to railways, and the interaction among these factors is mostly non-linear. Natural factors are no longer the key to restrict the development of paddy fields. Driven by market interests, dryland that meets the conditions of paddy field transformation is converted to paddy fields. The spatial difference of paddy field change in Sanjiang Plain is the result of the interaction of various driving factors. The driving factors and their relationships are different in different periods. Geographic detectors can make a more comprehensive analysis of various influencing factors. The results can provide theoretical basis for the protection of cultivated land and the rational utilization of cultivated land resources in Sanjiang Plain. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 31

Main heading: Factor analysis

Controlled terms: Agriculture  -  Expansion  -  Food supply  -  Land reclamation  -  Land use  -  Landforms  -  Natural resources  -  Railroads  -  Reclamation  -  Remote sensing   -  Soils

Uncontrolled terms: Cultivated lands  -  Driving factors  -  GeoDetector  -  Paddy fields  -  Sanjiang plain  -  Spatial-temporal changes

Classification code: 403 Urban and Regional Planning and Development  -  442.2 Land Reclamation  -  481.1 Geology  -  483.1 Soils and Soil Mechanics  -  821 Agricultural Equipment and Methods; Vegetation and Pest Control  -  822.3 Food Products  -  922.2 Mathematical Statistics  -  951 Materials Science

DOI: 10.11975/j.issn.1002-6819.2019.06.030

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

21. Optimal hydraulic section of horizontal-bottom catenary channel

Accession number: 20192307005273

Title of translation:

Authors: Han, Yancheng (1); Liang, Mengyuan (1); Easa, Said M (2); Tang, Wei (1); Chu, Pingping (1); Gao, Xueping (3)

Author affiliation: (1) School of Water Conservancy and Environment, University of Jinan, Jinan; 250022, China; (2) Department of Civil Engineering, Ryerson University, Toronto; M5B 2K3, Canada; (3) State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin; 300072, China

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 90-99

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: A suitable channel section cannot only increase flow capacity of channel, improve efficiency of water resources, and reduce water leakage loss, but also decrease construction cost. This paper proposed a channel section with a horizontal bottom and catenary sides (HBC). The HBC section, on one hand, provided a larger flow capacity, lesser-sharp angles of stress concentration, less leakage, better slope stability and frost heave resistance than trapezoids and rectangles sections. On the other hand, it had lots of advantages of horizontal bottom sections, such as simpler construction, easier leveling and compaction of the foundation, and lesser construction cost. The most important advantage of this section was that the horizontal bottom and sides could be built with different materials or thickness for decreasing the construction cost or other purposes. The shape function for HBC was defined. The formulas for the flow area, wetted perimeter, and water surface width were presented. A simpler iterative algorithm for calculation of the normal depth was developed. The iterative convergence by this algorithm was evidenced. Comparisons showed that this simpler iterative algorithm was better than classic Newton iterative algorithm. The optimal model of the best hydraulic section of HBC was built. The general differential equations for all the sections having horizontal bottomed and curve sides were derived. The best hydraulic section of HBC channel was obtained according to Lagrange multiplier method and its characteristics were presented including shape factor, ratio of horizontal bottom width to shape factor etc. The results showed that the following optimum parameters were constant for the best hydraulic HBC section: bottom width to water depth, water surface width to depth, bottom width to shape factor, water surface width to shape factor, shape factor to water depth equals. The ratio of water surface width for catenary part to shape factor equaled 3.602, the ratio of bottom width to shape factor equaled 0.855, the ratio of bottom width to water depth equaled 0.405, and the ratio of shape factor to water depth equaled 0.474, and the ratio of total water surface width to water depth equaled 2.112. Various explicit formulae to calculate the normal depth, critical depth, shape factor, flow area, wetted perimeter and water surface width of the HBC section were derived for the best hydraulic section for HBC channel. These formulas should make the design of the HBC section easier and promote its practical applications. The optimum parameters of the best hydraulic section for existing horizontal bottom (HB) sections, such as trapezoidal, rectangle, horizontal bottomed parabolic, and horizontal bottomed semi-cubic parabolic were derived. The comparison results showed that the HBC section had larger discharge than those of existing horizontal bottom (HB) sections under the same conditions. In addition, the flow area, wetted perimeter, and water surface of the HBC section were the smallest, which means that earthwork cost, lining cost and land expropriation cost are all decreased, which means HBC section is more economical. Comparison with classic catenary section showed that the discharge of the HBC was larger than that of the classic catenary section under the same conditions. The flow area, wetted perimeter and water surface of the HBC were smaller than these of the classic catenary section, which means the HBC section has better hydraulic characteristics. Its economy was also superior to the traditional catenary section. The results were verified by examples. The proposed section should enrich existing types of open channel sections. The research provides a new practical and flexible channel section for channel design and theoretical support for horizontal-bottom catenary channel design and applications. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 35

Main heading: Iterative methods

Controlled terms: Differential equations  -  Hydraulics  -  Lagrange multipliers  -  Leakage (fluid)  -  Open channel flow  -  Overhead lines  -  Slope stability  -  Water resources  -  Wetting

Uncontrolled terms: Best hydraulic section  -  Catenary  -  Channels  -  Horizontal bottom  -  Shapes

Classification code: 406.2 Roads and Streets  -  444 Water Resources  -  631.1 Fluid Flow, General  -  632.1 Hydraulics  -  706.2 Electric Power Lines and Equipment  -  921.2 Calculus  -  921.6 Numerical Methods

DOI: 10.11975/j.issn.1002-6819.2019.06.011

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

22. Suitable dissolved gas improving atomization quality of biodiesel/diesel mixed fuel

Accession number: 20192307005289

Title of translation: /

Authors: Ye, Lihua (1); Liu, Tianyu (1); Shi, Aiping (2)

Author affiliation: (1) School of Automotive and Traffic Engineering, Jiangsu University, Zhenjiang; 212013, China; (2) School of agricultural equipment engineering, Jiangsu University, Zhenjiang; 212013, China

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 222-228

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: In order to improve the atomization quality of biodiesel and diesel-biodiesel blends containing dissolved gas, the Phase doppler particle analyzer(PDPA, a device that can accurately measures the diameter and velocity of droplets in a spray field)was used to analyse the atomization quality of diesel-biodiesel with and without dissolved gas in this paper. The PDPA measurement system was used to test mixed fuel with different volume ratios(B0, B30, B50, B70, B100) at nozzle diameters of 0.24 and 0.30 mm. The axial velocity and particle size distribution were measured and analyzed. Further, based on the mixed fuel, different volumes of CO2 were dissolved therein, and the percentage of dissolved gas in volume was 5.74%, 12.73% and 26.42%, respectively, and the atomization quality of the fuel containing CO2 was measured at nozzle diameters of 0.24 and 0.30 mm. The results showed that at a nozzle diameter of 0.24 mm and 0.30 mm, the sauter mean diameter(SMD) of the biodiesel was greater than that of diesel, the average diameter of diesel fuel was 25 μm lower than that of biodiesel at the axial length of 70 mm, the atomization quality of the mixed fuel was obviously improved compared with that of biodiesel, with the decrease of nozzle diameter, the atomization quality was greatly improved. When the volume content of CO2 was 26.42%(C26.42), the droplet size at the axial length of 70 mm was 13.1 μm smaller than that of B50. The droplet size of the B50 with dissolved gas volume ratio of 5.74%(C5.74) and 12.73%(C12.73) was 5.3 and 12.2 μm higher than that of B50 at the axial length of 70 mm, respectively. When the nozzle diameter was reduced from 0.30 mm to 0.26 mm, C5.74 and C12.73 had a greater inhibitory effect on atomization and the SMD increased by 8.43% and 6.82%, respectively. The atomization quality of C26.42 was enhanced as the nozzle diameter reduced and the SMD was decreased by 26.5%. The fuel that contains a small amount of CO2 had a larger SMD than that of the fuel without dissolved gas, and the inhibition effect on atomization was more obvious with the decrease of nozzle diameter. When the amount of dissolved gas was high, the atomization quality was promoted, and with the decrease of nozzle diameter, the promotion effect was enhanced. This study showed that dissolved gas can improve the atomization quality of biodiesel under certain conditions, dissolved gas in mixed fuel can overcome the disadvantages of high viscosity and density of biodiesel, improve the atomization quality of biodiesel and improve its combustion effect, biodiesel can be better used in internal combustion engines. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 28

Main heading: Biodiesel

Controlled terms: Atomization  -  Carbon dioxide  -  Combustion  -  Diesel engines  -  Dissolution  -  Drops  -  Emission control  -  Gases  -  Nozzles  -  Particle size   -  Particle size analysis  -  Two phase flow

Uncontrolled terms: Atomization quality  -  Dissolved gas  -  High speed photographs  -  Inhibition effect  -  Measurement system  -  Phase Doppler particle analyzer  -  Sauter mean diameter (SMD)  -  Sauter mean diamter

Classification code: 451.2 Air Pollution Control  -  523 Liquid Fuels  -  612.2 Diesel Engines  -  631.1 Fluid Flow, General  -  802.3 Chemical Operations  -  804.2 Inorganic Compounds  -  951 Materials Science

Numerical data indexing: Percentage 1.27e+01%, Percentage 2.64e+01%, Percentage 2.65e+01%, Percentage 5.74e+00%, Percentage 6.82e+00%, Percentage 8.43e+00%, Size 1.22e-05m, Size 1.31e-05m, Size 2.40e-04m, Size 2.50e-05m, Size 3.00e-04m to 2.60e-04m, Size 3.00e-04m, Size 5.30e-06m, Size 7.00e-02m

DOI: 10.11975/j.issn.1002-6819.2019.06.027

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

23. Temporal and spatial distribution and hazard assessment of hail disasters during crop growth period in Xinjiang

Accession number: 20192307005280

Title of translation:

Authors: Wang, Yun (1); Wang, Shigong (2); Wang, Xu (3); Ma, Yu (4)

Author affiliation: (1) College of Atmospheric Science of Lanzhou University, Key Laboratory of Arid Climatic Change and Reducing Disaster of Gansu Province, Lanzhou; 730000, China; (2) College of Atmospheric Science of Chengdu University of Information Technology, Plateau Atmosphere and Environment Key Laboratory of Sichuan Province, Chengdu; 610225, China; (3) Weather Modification Office of Xinjiang Uygur Autonomous Region, Urumqi; 830002, China; (4) Climate Center of Xinjiang Uygur Autonomous Region, Urumqi; 830002, China

Corresponding author: Ma, Yu(wangxu2323@vip.163.com)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 149-157

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Hail is a serious meteorological disaster that occurs frequently in the growing period of crops in Xinjiang. Based on 2 629 records of 3 major disaster elements: the occurrence times, disaster area and economic loss of hail disaster in 1951-2017, the temporal and spatial distribution of hail disaster in Xinjiang was analyzed. Based on the entropy weight method (EWM), the disaster loss index which can comprehensively express the 3 disaster information was constructed. According to the gamma distribution function of the disaster loss index, the classification criteria of the damage grade of hail disaster were given objectively and quantitatively. Then the harm of hail disaster was classified and evaluated. The reasons for the regional, seasonal and interannual variation of hail disasters in Xinjiang were explained with water vapor pressure and air mass index. Air mass forecast model of hail disasters was established based on the logical regression. The results showed that: 1) The annual number of occurrences, the area and the economic losses of hail disasters in Xinjiang were 39 times, 75 485 hm2, and 109.96 million yuan. The hail disasters concentrated from May to August, i.e. in the crop growth period, and mostly in June; Bozhou, Kuitun-Manas Valley, Zhaosu County, Aksu Prefecture and Kashgar Prefecture on both sides of the Tianshan Mountains and adjacent areas had the most occurrences of hail disasters, large area and heavy economic losses; the largest areas affected by the single hail were Manas River Basin and Aksu Prefecture. The area that suffered the most economic losses by the single hail was the northern part of Bazhou and Kashgar Prefecture. The 3 major disaster factors all showed a linear increase trend. The propensity rates were 1.2 times/year, 2 589 hm2/year, and 3.36 million yuan/year. All of them showed abrupt changes in 1983, 1981, and 1979, respectively. The mean values were significantly different before and after the abrupt changes, and the mean value after the abrupt changes was 3.9 times, 5.7 times and 3.6 times of that before the abrupt changes, respectively. 2) Using the disaster loss index, the hail disaster was classified into 4 hazard levels: general, heavier, serious and extra serious. The extra serious disaster area was located in Tacheng, Bozhou, Kuitun-Manas Valley, Zhaosu County, Aksu Prefeccture, and Jashi. Aksu Prefecture ranked first, followed by Bozhou. In recent years, the hail disasters in the extra serious disaster-hit areas have been on the rise, requiring major defense. Multi defense lines should be added to the moving path of hail cloud, and the density of anti-aircraft guns and rocket launchers should be increased to carry out large-scale anti-hail catalytic operation for the continuous moving and developing hail clouds in order to minimize the harm of hail disaster to the maximum extent. 3) Vapor pressure and air mass index were good indications of the water vapor conditions and atmospheric stability when the hail disaster happened. In the areas, seasons and years where or when water vapor pressure and air mass index were high, more hail disasters occurred, and vice versa. Vapor pressure and air mass index were the main reasons for the impact of disasters. The number of occurrences of disaster and the area planted with crops both had an impact on the affected area. The contribution rates of the former 2 to the linear growth trend of the latter were 93% and 7%, respectively. The water vapor pressure, air mass index and planting area were used as the factors, and an annual forecasting model forecasting high or low frequency of the occurrence times of hail disaster was established. The fitting accuracy of the model was 73% and the fitting effect was good. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 32

Main heading: Disasters

Controlled terms: Aircraft accidents  -  Catapults (aircraft launchers)  -  Crops  -  Distribution functions  -  Forecasting  -  Hazards  -  Hydrostatic pressure  -  Landforms  -  Losses  -  Models   -  Network security  -  Precipitation (meteorology)  -  Rockets  -  Spatial distribution  -  Vapor pressure  -  Water vapor

Uncontrolled terms: Atmospheric stability  -  Classification criterion  -  Gamma distribution function  -  Influencing factor  -  Meteorological disasters  -  Seasonal and interannual variations  -  Temporal and spatial distribution  -  Water vapor conditions

Classification code: 443.3 Precipitation  -  481.1 Geology  -  631.1.1 Liquid Dynamics  -  641.1 Thermodynamics  -  654.1 Rockets and Missiles  -  672.2 Noncombat Naval Vessels  -  723 Computer Software, Data Handling and Applications  -  821.4 Agricultural Products  -  911.2 Industrial Economics  -  914.1 Accidents and Accident Prevention  -  921 Mathematics  -  922.1 Probability Theory

Numerical data indexing: Percentage 7.00e+00%, Percentage 7.30e+01%, Percentage 9.30e+01%

DOI: 10.11975/j.issn.1002-6819.2019.06.018

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

24. End-loss and compensation for small linear Fresnel collectors in severe cold area

Accession number: 20192307005287

Title of translation:

Authors: Yan, Suying (1, 2); Chen, Zhuang (1); Zhao, Xiaoyan (1); Ma, Jing (1); Wu, Yuting (3); Tian, Rui (1, 2)

Author affiliation: (1) College of Energy and Power Engineering, Inner Mongolia University of Technology, Hohhot; 010051, China; (2) Inner Mongolia Renewable Energy Key Laboratories, Inner Mongolia University of Technology, Hohhot; 010051, China; (3) College of Environmental and Energy Engineering, Beijing University of Technology, Beijing; 100124, China

Corresponding author: Zhao, Xiaoyan(NGZXY@imut.edu.cn)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 206-213

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: The linear Fresnel solar concentrating collector has been widely used in the field of solar heat source utilization due to its compact structure, easy manufacture and low price. Because there is a certain distance between the primary mirror and the collector, the position of the sunlight after reaching the collector changes with the incident angle of the sun, and a part of the reflected light will run out of the collector end to form the end-loss. For the large linear Fresnel collector systems, the end-loss length accounts for a small proportion of the length of the collector, while for the small linear Fresnel systems, the end-loss length accounts for a large proportion of the length of the collector, it has a great influence on the heat collection performance of the collector, so it is particularly important to reduce the end loss. According to the geographical location, the end-loss length of a north-south linear Fresnel mirror field is difference. Based on this, aiming at the serious end- loss of linear Fresnel collector in severe cold area, taking the small linear Fresnel collector system in Hohhot area(north latitude 40.87°) as the research object, the end-loss of linear Fresnel collector placed along the horizontal north-south axis and its adjustment and compensation method were studied and verified by experiments in this paper. The experiment bench was developed on a building roof. The linear Fresnel experimental system was mainly composed of a primary mirror, a compound parabolic secondary mirror and a glass-metal vacuum heat collecting tube. After the light reflected by the plane mirror, part of the light was directly absorbed by the vacuum heat collecting tube, and the other part was absorbed by the vacuum heat collecting tube after the secondary reflection of CPC(compound parabolic collector). The change of end-loss in different seasons and different collector heights was analyzed and calculated theoretically, a method of adjusting reflectors to compensate end-loss was proposed. The focal spot length of collector at different time before and after end-loss compensation was captured by infrared thermal imager, and the change of instantaneous heat collection efficiency before and after reflectors adjustment was analyzed. The results showed that the end-loss length was mainly caused by the horizontal distance from the mirror field to the collector, the height of the collector, the solar azimuth angle and height angle. The end-loss length could be reduced by raise the height of the collector under the premise of avoiding the occlusion and shadow loss between the mirror elements. Meanwhile, the end loss could be reduced by increasing the angle between the mirror and the north-south horizontal plane according to the seasonal variation, and the angle should be kept within the theoretical range. The length of the end-loss decrease to about 1/10 of the collector length after the northern end of the mirror field was raised to 20°at summer solstice afternoon, and the instantaneous heat collecting efficiency increased to 65.9% at noon, which was 54.5% higher than that of before compensation. The change trend of the end-loss with time was the same as that of the sun altitude angle in the middle of the day, contrary to the change trend of the sun azimuth angle, the end-loss at noon was the largest, and the en-loss at morning and evening was the smallest. In the same period of time, the end-loss was the largest in winter, the smallest in summer, and almost the same in spring and autumn. The study provided a theoretical reference for reducing the loss-end length of small linear Fresnel concentrating collectors in severe cold area. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 25

Main heading: Collector efficiency

Controlled terms: Heat transfer  -  Mirrors  -  Reflection  -  Solar energy

Uncontrolled terms: Collecting efficiency  -  Compound parabolic collector  -  Concentrating collector  -  Geographical locations  -  Infrared thermal imager  -  Linear Fresnel collectors (LFC)  -  Reflector adjustment  -  Severe cold areas

Classification code: 641.2 Heat Transfer  -  657.1 Solar Energy and Phenomena  -  702.3 Solar Cells  -  741.3 Optical Devices and Systems

Numerical data indexing: Percentage 5.45e+01%, Percentage 6.59e+01%

DOI: 10.11975/j.issn.1002-6819.2019.06.025

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

25. Multi-scale spatial distribution analysis of leisure agriculture in Beijing based on kernel density estimation

Accession number: 20192307005295

Title of translation:

Authors: Han, Chunmeng (1, 2); Liu, Huiping (1, 2); Zhang, Yanghua (1, 2); Wang, Juan (1, 2)

Author affiliation: (1) Faculty of Geographical Science, Beijing Normal University, Beijing; 100875, China; (2) Beijing Key Lab of Environmental Remote Sensing and Digital City, Beijing; 100875, China

Corresponding author: Liu, Huiping(hpliu@bnu.edu.cn)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 271-278

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: With the improvement of urban economic development, leisure agriculture becomes one of the important forms of the integration development of rural and urban region. The distributions pattern of the leisure agriculture could be studied in multi-scale (from local scale to regional scale). Based on regional economic statistical data, recent researches exploring the spatial distribution pattern of leisure agriculture were difficult to accurately describe because the analyzing scale was too large. Recently, point of interest (POI) data has been widely applied to analyze features of the urban to show the spatial distribution patterns with advantages of large data volume, high position accuracy and the clear classification of the leisure agriculture format. While the researches on the distribution pattern of the leisure agriculture based on POI were rather inadequate. The key to apply kernel density estimation(KDE) for spatial distribution pattern of urban point element was exploring the suitable bandwidth. So far, most of researches on bandwidth determination of KDE were based on mathematical or visual interpretation methods. Considering the scale features of spatial distribution pattern, basing on POI data, applying the method of spatial autocorrelation to determine different bandwidths of KDE which suited to analyze the regional-scale and local-scale spatial distribution patterns, this paper has recognized and analyzed the multi-scale features of spatial distribution patterns on Beijing leisure agriculture. The spatial autocorrelation method contained 2 indices, Moran’I and Local Moran’I. With increasing of KDE bandwidth, the value of the normalized Moran’I gradually increased from 0 to 1 and the value of the normalized number of HH (a statistically significant cluster of high values) region from the result of local Moran’I decreased from 1 to 0. At this time, the result of KDE could express the regional scale distribution pattern of leisure agriculture and the detail features were covered. On the contrary, the result of KDE could express the small scale pattern of Beijing leisure agriculture and the detail features were obvious. Considering the variable characteristics of Moran’I, the number of HH and comprehensive I curves, this paper determined different bandwidths of KDE which suited to analyze the regional-scale and local-scale spatial distribution pattern of the leisure agriculture were 9 km and 3 km. Using the method of natural breaks, the results of KDE with 9 km or 3 km bandwidths were divided into three levels, high value, middle value and low value respectively. Then spatial distribution patterns with different scales were identified. Under the regional-scale, the spatial distribution pattern showed two rings and multi-centers. The interior ring away from the city center from 30 km to 50 km was one day tour zone. The exterior ring away from the city center from 50 km to 90 km was two days and up tour zone. It was found that a primary distribution center was lied in the sub-montane area in the east of Changping County, the southeast of Huairou County, the southwest of Miyun County. Two sub-centers were lied in the northeast of Miyun County and the southwest of Fangshan County. Under the local-scale, the spatial distribution pattern showed 26 centers divided into 3 classes by area size. Most centers lied in the sub-montane area in the north to the middle part of Beijing. Fewer lied in the rural-urban fringe area in the southeast and hills in the west of Beijing. The least lied in the central city area. Finally the literature analysis method was applied to certificate the multi-scale features of the spatial distribution pattern on Beijing leisure agriculture. The method proposed in this paper is effective to express the different scales of spatial distribution pattern on Beijing leisure agriculture. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 35

Main heading: Spatial distribution

Controlled terms: Agriculture  -  Autocorrelation  -  Bandwidth  -  Economics  -  Estimation  -  Regional planning  -  Rural areas  -  Spatial variables measurement  -  Statistics

Uncontrolled terms: Distribution  -  Kernel Density Estimation  -  Multi-scales  -  Pattern  -  Spatial autocorrelations  -  Suitable bandwidth determination

Classification code: 403.2 Regional Planning and Development  -  716.1 Information Theory and Signal Processing  -  821 Agricultural Equipment and Methods; Vegetation and Pest Control  -  921 Mathematics  -  922.2 Mathematical Statistics  -  943.2 Mechanical Variables Measurements  -  971 Social Sciences

Numerical data indexing: Size 3.00e+03m, Size 3.00e+04m to 5.00e+04m, Size 5.00e+04m to 9.00e+04m, Size 9.00e+03m

DOI: 10.11975/j.issn.1002-6819.2019.06.033

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

26. Analysis on soil nutrient influencing factors of winter wheat yield gaps of basic soil productivity by boundary line method in central and southern Hebei province

Accession number: 20192307005279

Title of translation:

Authors: Huang, Shaohui (1, 3); Jia, Liangliang (1); Yang, Yunma (1); Liu, Ketong (2)

Author affiliation: (1) Institute of Agricultural Resources and Environment, Hebei Academy of Agriculture and Forestry Sciences, Shijiazhuang; 050051, China; (2) Soil and Fertility Station of Hebei Province, Shijiazhuang; 050021, China; (3) Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing; 100081, China

Corresponding author: Jia, Liangliang(jiall@cau.edu.cn)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 141-148

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Basic soil productivity is an important indicator of soil production ability and it can ensure wheat yield stabilization for food security. The improvement of basic soil productivity can increase the production potential of farmland, increase the yield, control the amount of fertilizer in the appropriate range, reduce agricultural environmental pollution, and establish an environmental-friendly cropping pattern. Basic soil productivity can be characterized by crop yield without fertilization and has significant correlation with soil nutrients. Central and southern Hebei province is one of the main wheat producing areas in China. The analysis of yield nutrient influencing factors will benefit the soil fertility improvement and yield increasing in Hebei Province. Using 876 winter wheat demonstration field trails’ data, which come from the national soil testing and fertilizer formulation project in Hebei province from 2006 to 2013, we studied the basic wheat yield and basic yield gaps distributions and analyzed the basic yield contribution rates. Soil fertility index including soil organic matter, available nitrogen, available phosphorus, available potassium and soil pH were selected as influencing factors of yield in this study. We quantified the contribution rates of each soil nutrient factor to the basic yield gap of soil productivity by using the boundary line analysis method. The result showed that the yield of basic soil productivity was between 1 080 and 7 404 kg/hm2 with an average of 4 573 kg/hm2. Compared with the maximum yield, the yield gap was from 69 to 6 324 kg/hm2 with the mean value of 2 831 kg/hm2. The average contribution rate of basic soil productivity was 71.1%. There was great potential to increase grain yield. The contribution rates of basic soil productivity were significantly positively correlated with the increase of basic yield. When the basic yield increased by 1 000 kg/hm2, the soil contribution rates increased by 8%. The increase of soil basic soil productivity led to the increase of contribution rates of basic soil productivity. Models were constructed by boundary line analysis to fit the relationships between soil nutrient factors and basic soil productivity. We found that the yield boundary point of the soil nutrient factors all had good fitting relationships. The pH simulation was quadratic curve, and soil organic matter, available nitrogen, available phosphorus and available potassium were quadratic platform curve. The soil organic matter had the highest contribution rate to the basis soil productivity yield gaps, which was 16.6%, followed by pH and available nitrogen with the contribution rate of 10.9% and 10.5%, respectively. The contribution rates of available potassium and available phosphorus were 4.1% and 2.9%, respectively. The results suggest that the soil organic matter, pH and available nitrogen may be the primary factors improving fertility in Hebei province. The boundary line analysis also showed that the soil nutrient factors of pH value 8.1, organic matter 24.6 g/kg, available nitrogen 120.6 mg/kg, available phosphorus 12.4 mg/kg and available potassium 89 mg/kg were suitable for obtaining high yield of winter wheat. The boundary line analysis can be used to analyze regional scale soil nutrient factors for yield limiting, and guide the direction of soil fertility improvement for increasing basic yield productivity. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 35

Main heading: Soil pollution control

Controlled terms: Biogeochemistry  -  Biological materials  -  Crops  -  Factor analysis  -  Fertilizers  -  Food supply  -  Nitrogen  -  Nutrients  -  Organic compounds  -  Phosphorus   -  Potassium  -  Productivity  -  Simulation platform  -  Soil testing  -  Soils  -  Stabilization

Uncontrolled terms: Boundary lines  -  Fertility  -  Influencing factors  -  Soil productivity  -  Yield

Classification code: 461.2 Biological Materials and Tissue Engineering  -  481.2 Geochemistry  -  483.1 Soils and Soil Mechanics  -  549.1 Alkali Metals  -  804 Chemical Products Generally  -  804.1 Organic Compounds  -  821.4 Agricultural Products  -  822.3 Food Products  -  922.2 Mathematical Statistics

Numerical data indexing: Percentage 1.05e+01%, Percentage 1.09e+01%, Percentage 1.66e+01%, Percentage 2.90e+00%, Percentage 4.10e+00%, Percentage 7.11e+01%, Percentage 8.00e+00%

DOI: 10.11975/j.issn.1002-6819.2019.06.017

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

27. Effect of pasteurization and ultra-pasteurization on structure and thermal stability of fresh milk whey protein

Accession number: 20192307005299

Title of translation:

Authors: Wang, Xibo (1); Zhang, Anqi (1); Wang, Yuying (1); Cui, Qiang (1); Zhou, Guowei (1); Wang, Lin (1)

Author affiliation: (1) College of Food Science, 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: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 307-313

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Milk is rich in nutrition, and it is a good medium for microorganisms, therefore, heat treatment are commonly used to sterilize in the process of liquid milk processing. Although the heat treatment can kill microorganisms in milk, it is possible to change the nutritional value and functional properties of milk, so it is essential to study the effects of heat treatment on the structural and properties of milk proteins, especially on whey protein monomers and casein monomers. The heat treatment of milk is generally carried out by pasteurized, and the ultra-pasteurized milk is also very popular recently. At present, there are few reports on the effects of heat treatment on the structural properties of milk whey protein. In this paper, defatted milk obtained by centrifugation through fresh milk as raw material. Then, the skim milk is subjected to low temperature long-term and high-temperature pasteurization and ultra-pasteurization treatment, and the casein are extracted by isoelectric precipitation, and finally whey protein was detected by different detection methods and techniques. So the effects of pasteurization and ultra-pasteurization on the structure and thermal stability of whey protein were discussed. The results of the protein concentration and SDS-PAGE gel electrophoresis showed that the whey protein content extracted by the isoelectric point method after heat treatment was high and the casein content was substantially absent. The results of infrared spectroscopy showed that pasteurization had little effect on the secondary structure of whey protein, while the content of α-helix in whey protein was significantly reduced after ultra-pasteurization treatment, and the random curl content increased significantly, it indicated that there was no significant change in the secondary structure of whey protein after pasteurization treatment, and the development of disordered structure changed from ordered structure to disordered structure after superpasteurization treatment, thereby improving the thermal stability of whey protein. Fluorescence analysis showed the whey protein sample heat-treated at 121 for 5 s was red-shifted, indicating that super-pasteurization greatly changed the secondary and tertiary structure of whey protein, it is shown that too high temperature will destroy the tertiary structure of whey protein and increase the polarity of the protein microenvironment. DSC analysis showed thermal denaturation of whey protein sample treated at 121 for 5 s, the peak temperature was 99.9, which was higher than that of the pasteurized whey protein sample, indicating that the stability of the whey protein sample after the ultra-pasteurization treatment was significantly improved. This may be due to the ultra-high temperature treatment to fully denature the whey protein and increase the disordered structure in the protein, which also indicates that the whey protein aggregate formed by ultra-high temperature was heat stable and the degree of denaturation was irreversible. The production and demand of dairy products in China are very large and the consumer groups are extensive. Therefore, it is very important to carry out research on the related technology of dairy processing to ensure the quality and safety of dairy products and promote the healthy and rapid development of China’s dairy industry. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 30

Main heading: After-heat treatment

Controlled terms: Accident prevention  -  Casein  -  Dairies  -  Dairy products  -  Denaturation  -  Electrophoresis  -  Fluorescence  -  Heat treatment  -  Infrared spectroscopy  -  Microorganisms   -  Monomers  -  Nutrition  -  Pasteurization  -  Proteins  -  Red Shift  -  Stability  -  Structural analysis  -  Structural properties  -  Temperature  -  Thermodynamic properties   -  Thermodynamic stability

Uncontrolled terms: Effects of heat treatment  -  Isoelectric precipitation  -  Medium for microorganism  -  Protein concentrations  -  Secondary and tertiary structures  -  Thermal denaturations  -  Ultrahigh temperature  -  Whey proteins

Classification code: 408 Structural Design  -  408.1 Structural Design, General  -  461.7 Health Care  -  461.9 Biology  -  537.1 Heat Treatment Processes  -  641.1 Thermodynamics  -  701.1 Electricity: Basic Concepts and Phenomena  -  741.1 Light/Optics  -  804 Chemical Products Generally  -  804.1 Organic Compounds  -  822 Food Technology  -  914.1 Accidents and Accident Prevention  -  951 Materials Science

Numerical data indexing: Time 5.00e+00s

DOI: 10.11975/j.issn.1002-6819.2019.06.037

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

28. Design of double disc ditching and sowing combined working machine of Astragalus smicus for machine-harvested rice stubble field

Accession number: 20192307005265

Title of translation:

Authors: You, Zhaoyan (1); Wu, Huichang (1); Peng, Baoliang (1); Gao, Xuemei (1); Hu, Zhichao (1); Zhang, Yulan (1)

Author affiliation: (1) Nanjing Research Institute for Agricultural Mechanization, Ministry of Agriculture and Rural Affairs, Nanjing; 210014, China

Corresponding author: Wu, Huichang(huichangwu@126.com)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 18-28

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Astragalus smicus, also known as Chinese milk vetch, Zi yunying and so on, is one of the main winter green manure crops in paddy fields of central and southern China, it has the advantages of reducing fertilizer input, improving soil fertility, increasing crop yield and quality, and protecting ecological environment, and has strong nitrogen fixation ability and high utilization efficiency. In recent years, the production machinery of Astragalus smicus has been developed and applied rapidly in terms of capacity and utilization efficiency, but its development still lags behind. Ditching and sowing are important links in the production of Astragalus smicus. The yield of Astragalus smicus is largely determined by the quality of sowing, and ditching operation can make Astragalus smicus grow well in low-humid field with poor drainage or sandy soil with poor fertilizer and water retention. Astragalus smicus is often used as green manure in paddy field, but high stubble retention, large amount of straw, insufficient in sowing height of existing other sowing equipments, working parts easily clogged, etc., bring difficulties for mechanized production of Astragalus smicus. In order to solve the influence of machine-harvested rice stubble on mechanized production of Astragalus smicus, aiming at the problems of low quality and low production efficiency in independent ditching and sowing links at present, a Astragalus smicus ditching and sowing machine which suitable for machine-harvested rice stubble field was developed. A height adjustable sowing device was designed, by which the sowing components could be lifted to a proper position according to the residual straw situation in the field. The special seed-metering wheel and quantitative evenly-sowed device for Astragalus smicus were developed to achieve precision sowing and improve the sowing uniformity. The structure and working parameters of the double-disk ditching components were determined. The variation coefficients of ditching width and depth determined by field experiments were less than 6%, which met the drainage requirements of Astragalus smicus growth process. The multiple factor experiments and regression analysis of the test data were carried out by Design-expert software, the results showed that forward speed of machine, rotation speed of seed-metering wheel, seed-uniforming cylinder diameter significantly affected the sowing performance, the results of variance analysis showed that the rotation speed of seed-metering wheel had the greatest influence on the emergence rate and coefficient of variation of sowing uniformity, while the forward speed of machine had the least influence on the emergence rate and coefficient of variation of seed-metering quantity consistency, regarding the coefficient of variation of sowing uniformity, the most influential factor was seed-uniforming cylinder diameter, and the minimum impact factor was the rotation speed of seed-metering wheel, the optimal factor parameters combination which affected the sowing quality of Astragalus smicus ditching and sowing machine was as follows: forward speed of machine was 4.6 km/h, rotation speed of seed-metering wheel was 44 r/min, seed-uniforming cylinder diameter was 6 mm. Verified by field experiments, the Astragalus smicus emergence rate was 95.87%, quantity consistency was 12.7%, coefficient of variation of sowing uniformity was 8.07% in the condition of optimal parameter combination, the relative error was below 3% compared with optimal values predicted by the model. Compared with the existing sowing methods of Astragalus smicus, working efficiency of the designed ditching and sowing machine was 1 hm2/h, which was superior to the artificial sowding working efficiency of 0.1 to 0.125 hm2/h, the hand-shaking working efficiency of 0.2 to 0.3 hm2/h and the motorized sowing working efficiency of 0.5 to 0.8 hm2/h, and was lower than the UAV sowing working efficiency of 3 to 4 hm2/h. In addition, the coefficient of variation of sowing uniformity and the combination type of ditching and sowing machine were also significantly superior to that of other methods. The Astragalus smicus ditching and sowing machine developed in the paper integrated ditching and sowing links in one operation, the working efficiency was greatly improved, the research provided a new method for Astragalus smicus ditching and sowing machine for machine-harvested rice stubble field. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 33

Main heading: Efficiency

Controlled terms: Agricultural machinery  -  Crops  -  Cylinders (shapes)  -  Design  -  Harvesting  -  Machine design  -  Manures  -  Nitrogen fertilizers  -  Nitrogen fixation  -  Optimization   -  Quality control  -  Regression analysis  -  Rotation  -  Software testing  -  Speed  -  Wheels

Uncontrolled terms: Astragalus smicus  -  Coefficient of variation  -  Ecological environments  -  Optimal parameter combinations  -  Rice stubble field  -  Sowing machines  -  Structure and working parameters  -  Utilization efficiency

Classification code: 601 Mechanical Design  -  601.2 Machine Components  -  723.5 Computer Applications  -  802.2 Chemical Reactions  -  804 Chemical Products Generally  -  821 Agricultural Equipment and Methods; Vegetation and Pest Control  -  913.1 Production Engineering  -  913.3 Quality Assurance and Control  -  921.5 Optimization Techniques  -  922.2 Mathematical Statistics  -  931.1 Mechanics

Numerical data indexing: Percentage 1.27e+01%, Percentage 3.00e+00%, Percentage 6.00e+00%, Percentage 8.07e+00%, Percentage 9.59e+01%, Rotational_Speed 4.40e+01RPM, Size 6.00e-03m, Velocity 1.28e+00m/s

DOI: 10.11975/j.issn.1002-6819.2019.06.003

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

29. City water-saving green space system planning based on GIS technology

Accession number: 20192307005296

Title of translation: GIS

Authors: Liu, Huimin (1); Gong, Siyu (1); Zou, Tiean (2); Pei, Yingxin (3); Pu, Jie (1); Jiang, Shan (1); Wang, Xuena (1); Fu, Xingyuan (1)

Author affiliation: (1) College of Horticulture and Gardening, Northeast Agricultural University, Harbin; 150030, China; (2) College of Resources and Environment, Northeast Agricultural University, Harbin; 150030, China; (3) Zhicheng Patent Agency Firm in Dalian, Dalian; 116000, China

Corresponding author: Fu, Xingyuan(1292676240@qq.com)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 279-287

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: In city green space planning, plant evapotranspiration (ET) and rainwater supply haven’t considered. In this study, city water-saving green space system was planned based on GIS technology by considering the plant ET and rainwater supply. We would take full advantage of rainwater resources and plan ecological green space system with water-saving function for the core area of Songbei in Harbin. The GIS technology was used for extraction of underlying subsurface of collectable rainwater for calculation of utilizable rainwater. Plant ET was calculated by Penman-Monteith formula. The results showed that the rainfall in the study area was concentrated in a range of 485-671 mm. The average rainfall of 30 years was 524.5 mm. The rainfall maximized in the year of 1994 (524.5 mm) and minimized in the year of 1989(345.5 mm). The rainfall from June to August accounted for 66.4% of the annual rainfall. Among 5 levels, light and moderate rain were the main levels of rainfall and total of them accounted for 69.3% of the total rainfall. Rainwater resources utilization was annually 5 126 800 m3. The total of the plant ET was annually 6 397 100 m3 from May to October while in the same time the total amount of rainwater could be collected 4 561 700 m3. The rainwater resource could reach 71.31% of plant ET. Water demand of plants was mostly consistent with rainfall period. The rainwater harvesting amount in July and August could fully meet the requirement of water by plants, however, the rainwater was less than the required water by plants in the other months especially in May. The rainwater harvested in May only accounted for 28.35% of plant ET. The distribution map of water-saving green space of study area was built up. The green space with the slope between 3° and 15° was designed as the infiltration type greenbelt, and the slope less than 3° was as the water-collecting green space, and by the DEM model, the area of potential water-saving green space could reach 1 664.19 hm2, which was 37.10% of the research area. By using the theory of hydraulic engineering and geographic information science, and taking the water-saving green space as the main body, the water-saving green space system with using rainwater resource was planned for the study area. The system structure was one green ring, three green belts, three vertical and three horizontal green belts, one green isolation belt, one green core, one green region, two green spaces and multiple green points. Five basic types of green space were planned for the study area with park green space (19%), production green space (2%), protective green space (8%), affiliated green space (10%) and the other green space (4%). So the green coverage rate could reach 48% and park coverage rate would reach more than 85%, and the long-term green space rate would reach 43%. This paper showed a method for planning urban green space system with water-saving ecological function so that the water resources in urban could be fully utilized. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 35

Main heading: Water conservation

Controlled terms: Ecology  -  Evapotranspiration  -  Fluid mechanics  -  Geographic information systems  -  Planning  -  Rain  -  Shore protection

Uncontrolled terms: Geographic information science  -  Green space system planning  -  Green spaces  -  Harbin  -  Penman-Monteith formula  -  Rainwater resources  -  Urban green space systems  -  Water - savings

Classification code: 407.1 Maritime Structures  -  443.3 Precipitation  -  444 Water Resources  -  454.3 Ecology and Ecosystems  -  903.3 Information Retrieval and Use  -  912.2 Management  -  931.1 Mechanics

Numerical data indexing: Age 3.00e+01yr, Percentage 1.00e+01%, Percentage 1.90e+01%, Percentage 2.00e+00%, Percentage 2.84e+01%, Percentage 3.71e+01%, Percentage 4.00e+00%, Percentage 4.30e+01%, Percentage 4.80e+01%, Percentage 6.64e+01%, Percentage 6.93e+01%, Percentage 7.13e+01%, Percentage 8.00e+00%, Percentage 8.50e+01%, Size 3.46e-01m, Size 4.85e-01m to 6.71e-01m, Size 5.24e-01m, Volume 1.27e+05m3, Volume 3.97e+05m3, Volume 5.62e+05m3

DOI: 10.11975/j.issn.1002-6819.2019.06.034

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

30. Methane production performance of semi-continuous alcoholization/acidification type two-phase anaerobic digestion

Accession number: 20192307005290

Title of translation:

Authors: Yu, Miao (1); Gao, Ming (1, 2); Wu, Chuanfu (1, 2); Ren, Yuanyuan (1); Ma, Xinxin (1); Wang, Qunhui (1, 2)

Author affiliation: (1) Department of Environmental Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing; 100083, China; (2) Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, Beijing; 100083, China

Corresponding author: Wu, Chuanfu(wuchuanfu83@163.com)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 229-234

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: A novel semi-continuous two-phase anaerobic digestion(AD) system characterized by methanogenesis from alcoholization was constructed, and the organic loading rate of the system was gradually increased from 2.0 to 6.0 g/ (L•d). According to the previous research results, the HRT(hydrodynamic retention time) of the first phase of the alcoholization/acidification type semi-continuous two-phase AD system was set for 2 d. Compared to the first phase of the traditional two-phase anaerobic digestion, the HRT was set for 2, 5, and 8 days, respectively. After 25 days of continuous operation, the change tendencies of acetic acid, propionic acid, butyric acid, etc. in the first phase hydrolysis products were analyzed under a certain OLR (organic loading rate). The results showed that when the acidification phase residence time was 5 and 8 days, the hydrolysis acidification effect of the system was better than that at 2 days, which may be due to the stable state of the acidified bacteria microbial community in the system. Therefore, in this experiment, 5 days was selected as the hydraulic retention time of the acidified phase. The methanogenic phase volume of the two systems was 8 L and the hydraulic retention time was 25 d. The results showed that 5.0 g/(L•d) was the maximum OLR for stable operation of the two systems in the study. By comparing the alcoholization/acidification type system with the traditional two-phase anaerobic digestion system, when the maximum OLR of the system reached 5.0 g/(L•d), the methane yield of the alcoholization/acidification type system reached 421.52 mL/g, which was 6.8% higher than that of the traditional system (394.48 mL/g). In this study, the TVFA (total volatile fatty acid)/alkalinity ratio was a more sensitive indicator than the pH value to detect the operating state of the methanogenic phase. The ethanol concentration in the first phase of the alcoholization/acidification type system accounted for 33.4%, which was beneficial to maintain the pH value and the stable operation of anaerobic digestion after the materials in the first phase entered to the second phase. Compared with the traditional two-phase anaerobic digestion system, the alcoholization/acidification type system had a shorter first phase hydraulic retention time of 2 days. Moreover, comparing with the traditional two-phase system, the volume methanogenesis rate of alcoholization/acidification type system was increased by 18.3%. All of the results showed that the alcoholization/acidification type system had obvious advantages in the methanogenic performance compared with the traditional system. And it also had the potential to improve system stability and reduce the scale of the plant and save the energy required for hydrolysis acidification in industrial applications. By comparing the first phase of the two systems, it could be found that the total amount of hydrolyzed products in the two groups was close when the OLR was 3.0 and 4.0 g/(L•d). When the OLR increased to 5.0 g/(L•d), the ethanol proportion in the first phase of the alcoholization/acidification type system was higher than that in the traditional two-phase system. Meanwhile, the propionic acid concentration was lower than that of the traditional two-phase system. Propionic acid was a substance which was more difficult to be degraded by methanogens in all volatile fatty acids, and its accumulation in the methanogenic phase inhibited the activity of methanogens. These results showed that it was beneficial to keep a stable pH value and alkalinity environment for the methanogenic phase, which ensured the advantage to improve the stability of the anaerobic system. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 27

Main heading: Anaerobic digestion

Controlled terms: Acidification  -  Alkalinity  -  Butyric acid  -  Digestive system  -  Ethanol  -  Fermentation  -  Hydrolysis  -  Methane  -  Methanogens  -  pH   -  Propionic acid  -  Saturated fatty acids  -  System stability  -  Volatile fatty acids  -  Wastes

Uncontrolled terms: Alcoholizable/acidogenic phase  -  Ethanol concentrations  -  Hydraulic retention time  -  Hydrolysis acidification  -  Microbial communities  -  Organic loading rates  -  Total volatile fatty acids  -  Two phase anaerobic digestion

Classification code: 461.2 Biological Materials and Tissue Engineering  -  461.9 Biology  -  801.1 Chemistry, General  -  802.2 Chemical Reactions  -  804.1 Organic Compounds  -  822.2 Food Processing Operations  -  961 Systems Science

Numerical data indexing: Age 1.37e-02yr, Age 2.19e-02yr, Age 5.48e-03yr, Age 6.85e-02yr, Percentage 1.83e+01%, Percentage 3.34e+01%, Percentage 6.80e+00%, Specific_Volume 3.94e-01m3/kg, Specific_Volume 4.22e-01m3/kg, Volume 8.00e-03m3

DOI: 10.11975/j.issn.1002-6819.2019.06.028

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

31. Land cultivation suitability evaluation of agro-pastoral ecotone in northern China based on aspects of ecology, production and life

Accession number: 20192307005293

Title of translation:

Authors: Zhou, Jian (1); Zhang, Fengrong (2); Xu, Yan (2); Qiu, Menglong (1)

Author affiliation: (1) Northwest Land and Resources Research Center, Shaanxi Normal University, Xi’an; 710119, China; (2) College of Land Science and Technology, China Agricultural University, Beijing; 100193, China

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 253-260

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Agro-pastoral ecotone in northern China is fragile in ecology. Desertification is the prominent eco-environmental problem which is mainly induced by unreasonable land use in this area. In the background of ecological civilization construction in China, it is significant to study land suitability for cultivation in the agro-pastoral ecotone in northern China to prompt ecological protection and scientific utilization of land resource. Taking Horqin Left Back Banner as a case study, from the aspects of ecology, production and life, this paper constructed the evaluation index system to evaluate land suitability for cultivation. The results showed that the unsuitable cultivation area in cultivated land in Horqin Left Back Banner was 15 996.87 hm2 accounting for 5.339% of total cultivated land area. Owing to ecological, production and living factors, the unsuitable cultivation area of cultivated land were 7 519.23, 9 337.23 and 6 039.99 hm2 and their proportions were 40.78%, 32.84% and 26.38%, respectively. There were 6 unsuitable cultivation types including ecology; production; ecology and production; ecology and life; production and life; ecology, production and life. We reckon that unsuitable cultivation land should be de-farmed firstly in Grain for Green Project. The grass land suitable for cultivation was 197 195.94 hm2 accounting for 32.18% in total grass land area. Namely, about a third of the grass land could be reclaimed into cultivated land in Horqin Left Back Banner. However, it was found that the proportion of high quality grass land suitable for cultivation was very small from perspectives of soil suitability and topographic conditions. From the perspective of soil suitability, the most suitable, the moderate suitable and the low suitable were 26 058.42, 34 347.78, 136 789.74 hm2, accounting for 13.214%, 17.418%, 69.367% of the total grass land suitable for cultivation, respectively. From the perspective of topography condition, when the micro topography index were [1.5, 1.6), [1.6, 1.7), [1.7, 1.8) and [1.8, 1.9),the grass land areas were 0.18, 0, 8.1 and 277.29 hm2, accounting for 0, 0, 0.004% and 0.141% of the total grass land area suitable for cultivation, respectively. However, when the micro topography index were [1.9, 2.0), [2.0, 2.1), [2.1, 2.2), the grass land area were 82 389.24, 112 996 and 1 525.05 hm2 respectively, accounting for 41.780%, 57.301% and 0.773% of the total grass land area suitable for cultivation. From two aspects of soil suitability and topography condition, the grass land area proportion of soil suitability for most grade and micro topographic index for [1.5, 1.9) was only 0.039% to the total grass land area suitable for cultivation. And the grass land area proportion of soil suitability for most and moderate grade and micro topographic index for [1.5, 1.9) was only 0.085% to the total grass land area suitable for cultivation. In order to avoid the destruction of ecological environment and the expansion of desertification caused by the reclamation of low quality grass land, it is suggested that priority should be given to the high quality reserved cultivated land resource in reclamation and the national coordination should be maintained in cultivated land balance across provincial region. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 32

Main heading: Land reclamation

Controlled terms: Climatology  -  Ecology  -  Land use  -  Natural resources  -  Production  -  Reclamation  -  Soils  -  Topography

Uncontrolled terms: Agro-pastoral ecotones  -  Ecological environments  -  Evaluation index system  -  Grain for green projects  -  Horqin Left Back Banner  -  Land suitability  -  Life  -  Northern China

Classification code: 403 Urban and Regional Planning and Development  -  442.2 Land Reclamation  -  443 Meteorology  -  454.3 Ecology and Ecosystems  -  483.1 Soils and Soil Mechanics  -  951 Materials Science

Numerical data indexing: Percentage 1.32e+01%, Percentage 1.41e-01%, Percentage 1.74e+01%, Percentage 2.64e+01%, Percentage 3.22e+01%, Percentage 3.28e+01%, Percentage 4.00e-03%, Percentage 4.08e+01%, Percentage 4.18e+01%, Percentage 5.34e+00%, Percentage 5.73e+01%, Percentage 6.94e+01%, Percentage 7.73e-01%

DOI: 10.11975/j.issn.1002-6819.2019.06.031

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

32. Vector control optimization of bearingless induction motor considering skin effect of cage rotor

Accession number: 20192307005270

Title of translation:

Authors: Yang, Zebin (1); Bao, Chunfeng (1); Sun, Xiaodong (2); Lu, Jiang (1); Chen, Xi (1)

Author affiliation: (1) College of Electrical and Information Engineering, Jiangsu University, Zhenjiang; 212013, China; (2) Automotive Engineering Research Institute, 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: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 65-73

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: The bearingless induction motor (BIM) is a new type motor without contact and friction and has the function of rotation and suspension. The rotor parameters are important factors that affect the accuracy of the field orientation control strategy of BIM, however, they are easily affected by the skin effect during the process of starting and high speed running, which result in the changes of rotor resistance and leakage inductance. The variations of the rotor parameters will cause the deviation of field orientation and reduce the motor control performance. Aiming at these problems, a parameter identification method based on finite element calculation and least square method was proposed in this paper. Firstly, based on the analysis of suspension force generation principle of BIM, the 2 D finite element model of the motor was constructed and values of the rotor resistance and leakage inductance at different frequencies were calculated by the finite element simulation. Then, by reasoning on the mathematical model, the influence of skin effect on the rotor field orientation and suspension control of BIM was analyzed in detail. The results showed that the variations of rotor parameters caused by the skin effect would affect rotor flux field orientation and made the actual suspension force deviate from the given value. Next, the least square method was used to realize fast identification of the rotor parameters, and the function relationship between rotor parameters and current frequency was obtained. Based on this, a parameters identification model was presented and a BIM field-oriented control system with considering rotor skin effect was proposed. The real-time value of the rotor resistance was obtained through the identification module to correct the phase angle deviation of rotor flux linkage so as to completely decouple torque component and exciting component. Finally, in order to verify the accuracy and effectiveness of the proposed control strategy based on curve fitting identification by the least square method, the simulation of BIM vector control system was established by MATLAB Simulink toolbox. Simulation results showed the motor took about 0.12 s arriving at the given speed after considering the skin effect, the response speed increased by 20% and the overshoot of speed response was very small. The maximum displacement in the x direction was reduced from about 12 μm to 8 μm and the maximum displacement in the y direction was reduced from about 24 μm to 18 μm after considering the skin effect. That means the motor could enter stable suspension state quickly and had a good suspension performance. To further validate the feasibility and effectiveness of the proposed control method, a BIM prototype was taken as experimental object, and a digital control system based on DSP TMS320F2812 was constructed. In the process of experiment, the rotor speed was measured by photoelectric encoder so as to calculate the slip frequency. The displacement of the BIM was measured by the eddy current displacement sensor to determine the required suspension force. The experimental results showed the speed rise time reduced from 0.2 s to 0.15 s with considering the skin effect, the response speed increased by 25%. This indicated the motor had a good start performance. And the peak to peak values of the rotor radial displacement decreased from 40 μm to 20 μm, reduced by about 50%. The proposed control strategy of the BIM can effectively improve speed response and reduce the radial displacement, and achieve good torque and suspension performance. This study can provide a reference for the performance optimization of BIM control system. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 30

Main heading: Vector control (Electric machinery)

Controlled terms: Architectural design  -  Automobile seats  -  Control engineering  -  Curve fitting  -  Digital control systems  -  Finite element method  -  Inductance  -  Induction motors  -  Least squares approximations  -  MATLAB   -  Motors  -  Optimization  -  Parameter estimation  -  Skin effect  -  Speed

Uncontrolled terms: Bearingless induction motor  -  Eddy current displacement sensors  -  Finite element simulations  -  Infinite element  -  Least square methods  -  Parameter identification methods  -  Performance optimizations  -  Suspension force

Classification code: 402 Buildings and Towers  -  662.4 Automobile and Smaller Vehicle Components  -  701.1 Electricity: Basic Concepts and Phenomena  -  705.3.1 AC Motors  -  731.1 Control Systems  -  731.2 Control System Applications  -  921 Mathematics

Numerical data indexing: Percentage 2.00e+01%, Percentage 2.50e+01%, Percentage 5.00e+01%, Size 1.20e-05m to 8.00e-06m, Size 2.40e-05m to 1.80e-05m, Size 4.00e-05m to 2.00e-05m, Time 1.20e-01s, Time 2.00e-01s to 1.50e-01s

DOI: 10.11975/j.issn.1002-6819.2019.06.008

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

33. Impact of different rural land consolidation modes on farmers’ dependence on ecosystem services

Accession number: 20192307005294

Title of translation:

Authors: Zhang, Chaozheng (1); Yang, Gangqiao (1); Wen, Gaohui (2)

Author affiliation: (1) College of Public Administration, Huazhong Agricultural University, Wuhan; 430070, China; (2) College of Resources and Environmental Science, Hunan Normal University, Changsha; 410081, China

Corresponding author: Yang, Gangqiao(ygq@mail.hzau.edu.cn)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 261-270

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Implementing rural land consolidation projects (RLCP) is believed to be an intervention that is effective at alleviating the problem of “agriculture, rural areas and farmers”, as well as optimizing the spatial pattern and service functions of ecosystem. Evaluation on ecological benefits of RLCP depends on the value of ecosystem services, as well as the effective assessment of farmers well-being change caused by policy choices or farmers’ activities, integrating and quantifying farmers’ net income from ecosystem services is the key to providing scientific and effective decision-making for the relationship balance between farmers well-being and ecosystem services. In recent years, some places carried out RLCP in new agricultural business entities-dominant mode, which was different from local government-dominant mode. This study aimed to analyze the impact of different RLCP modes on the dependence on ecosystem services from the micro-perspective of farmers. Based on the construction of index system of farmer dependence on ecosystem services (IDES), we investigated 483 farmers of 4 counties and cities in Hubei Province for livelihood data of 2014 and 2017, and then integrated and quantified the net income from ecosystem services and dependence on ecosystem services of farmers. Difference-in-differences model was employed to analyze the difference of farmers’ net income from ecosystem services and dependence on ecosystem services between consolidated areas and unconsolidated areas, and that between new agricultural business entities-dominant mode areas and local government-dominant mode areas. The results indicate that: 1) The income from provisioning service, regulating services, cultural services, ecosystem services and other social-economic activities increased by 33.20%, 5.34%, 35.09%, 32.12% and 33.23% respectively in consolidated areas after consolidation. The income increased by 53.06%, 5.40%, 33.33%, 49.33% and 42.40% respectively in new agricultural business entities-dominant mode areas. The income increased by 6.46%, 5.25%, 38.89%, 8.24% and 27.02% respectively in local government-dominant mode areas, while they increased by 17.01%, 4.66%, 22.34%, 16.85% and 22.98% respectively in unconsolidated areas at the same time; 2) The index of provisioning service, regulating services, cultural services and ecosystem services changed by -28.60%, -21.05%, -6.45% and -26.91% in consolidated areas after consolidation, they changed by -36.57%, -24.69%, -16.24% and -34.52% respectively in new agricultural business entities-dominant mode areas, they changed by -18.97%, -17.27%, +16.42% and -17.59% respectively in local government-dominant mode areas, while they changed by -8.34%, -13.39%, -4.10% and -8.36% respectively in unconsolidated areas at the same time. Implementing RLCP is an effective way to optimize farmers’ income structure and reduce farmers’ dependence on ecosystem services, which increases the share of socio-economy income and reduces the share of ecosystem-service income, and the effect of new agricultural business entities-dominant mode is more obvious than that of government-dominant mode. There is still much room for improvement in local government-dominant mode to optimize farmers’ income structure and reduce farmers’ dependence on ecosystem services. This study provides approach and method for linking ecosystem services and farmers well-being at micro-scale, as well as policy implication for reasonable and continuous promotion of RLCP. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 39

Main heading: Ecosystems

Controlled terms: Agriculture  -  Decision making  -  Economics  -  Land use  -  Petroleum reservoir evaluation  -  Public policy  -  Rural areas

Uncontrolled terms: Agricultural business  -  Difference-in-differences models  -  Ecological benefits  -  Ecosystem services  -  Land consolidations  -  Mode  -  Value of ecosystem services  -  Well being

Classification code: 403 Urban and Regional Planning and Development  -  454.3 Ecology and Ecosystems  -  512.1.2 Petroleum Deposits : Development Operations  -  821 Agricultural Equipment and Methods; Vegetation and Pest Control  -  912.2 Management  -  971 Social Sciences

Numerical data indexing: Percentage -1.34e+01%, Percentage -1.62e+01%, Percentage -1.73e+01%, Percentage -1.76e+01%, Percentage -1.90e+01%, Percentage -2.11e+01%, Percentage -2.47e+01%, Percentage -2.69e+01%, Percentage -2.86e+01%, Percentage -3.45e+01%, Percentage -3.66e+01%, Percentage 4.24e+01%, Percentage 4.66e+00%, Percentage 4.93e+01%, Percentage 5.25e+00%, Percentage 5.31e+01%, Percentage 5.34e+00%, Percentage 5.40e+00%, Percentage 6.46e+00%, Percentage 8.24e+00%, Percentage -4.10e+00%, Percentage -6.45e+00%, Percentage -8.34e+00%, Percentage -8.36e+00%, Percentage 1.69e+01%, Percentage 1.70e+01%, Percentage 2.23e+01%, Percentage 2.30e+01%, Percentage 2.70e+01%, Percentage 3.21e+01%, Percentage 3.32e+01%, Percentage 3.33e+01%, Percentage 3.51e+01%, Percentage 3.89e+01%

DOI: 10.11975/j.issn.1002-6819.2019.06.032

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

34. Analysis and verification of terminal position error of leg parallel mechanism of quadruped robot

Accession number: 20192307005267

Title of translation:

Authors: Wang, Xiaolei (1, 2); Jin, Zhenlin (1, 3); Li, Xiaodan (2)

Author affiliation: (1) College of Mechanical Engineering, Yanshan University, Qinhuangdao; 066004, China; (2) College of Mechanical Engineer and Automation, Liaoning University of Technology, Jinzhou; 121001, China; (3) State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, Shanghai; 200240, China

Corresponding author: Jin, Zhenlin(zljin@ysu.edu.cn)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 39-46

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: In order to reasonably determine the manufacturing tolerance range of 2-DOF planar parallel mechanism parts on quadruped robot, the error sensitivity analysis of the leg parallel mechanism and the position precision estimation in the working space were proposed in this paper. The leg mechanism of the quadruped robot analyzed in the paper was composed of a 2-DOF planar parallel mechanism and a RPR mechanism in series. The planar parallel mechanism realized the forward direction of leg lifting and stepping, and the RPR mechanism realized the lateral pendulum movement of leg mechanism, and the coordinate movement of the 2 mechanisms realized the spatial movement of leg mechanism. The advantage of the leg structure was that the planar parallel mechanism could enlarge the stroke of the end position to achieve rapid leg lifting and stride, and the RPR mechanism could achieve lateral swing decoupling motion. In the manufacturing process of the leg mechanism, due to the relatively simple structure of RPR mechanism and the coupling and complexity of parallel mechanism, the manufacturing of 2-DOF planar parallel mechanism was emphatically analyzed. Firstly, the composition of the leg mechanism was introduced, the position equation of 2-DOF planar parallel mechanism was established, an error model of 2-DOF planar parallel mechanism was established by using the full differential theory, the mapping relation of each error source to the end position error was obtained. Secondly, the position error sensitivity model and evaluation index of the mechanism were established. The histogram of each geometric error source on the end position precision under the significance of generalization was drawn according the sensitivity evaluation index, and the influence degree of each error source on the end position precision was revealed. The result showed that the angle error sources had a great influence on the position precision of leg mechanism, the angle error between the rod BC and the X axis was the most sensitive, other angle errors were more sensitive, while the influence of other manufacturing error sources was relatively small. Then, according to the 3σ principle and sensitivity evaluation index, the allowable manufacturing tolerances of the parts of each error source were determined. Finally, according to the allowable manufacturing tolerance range, the actual parts were designed and processed. The manufacturing error values of each part were measured by using the three coordinate measuring instrument, and the actual manufacturing errors of each part were obtained. According to the error transfer model and the sensitivity evaluation index, the distribution of the end position precise in the workspace was estimated. At the same time, the representative 6 pose points in the working space of the experimental prototype were measured with the three coordinate measuring instrument, and the end precision estimation was verified by some examples. The result of precision estimation showed that the error value of the lower part of the working space was within the range of 0.18-0.3 mm, and the precision was higher; the error value of the upper part of the working space was within the range of 0.4-1 mm, and the precision was poor; and the precision of the upper part of the working space was worse, and the error of the left upper and top part was up to 1 mm. Therefore, when performing more precise tasks, the trajectory of the foot contacting to ground could be planned in the lower part of the workspace to improve the foot positioning precision. The experiments results showed that the maximum error absolute value between the actual position precision value and the theoretical position precision estimation was 0.003 8 mm, and the minimum error absolute value was 0.001 5 mm, which verifies the correctness of the error transfer model and the position precision estimation, and the validity of the method to determine the manufacturing tolerance of components. The results laid a foundation for the kinematics calibration, error compensation and trajectory planning of the leg mechanism of the quadruped robot. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 26

Main heading: Error compensation

Controlled terms: Fits and tolerances  -  Instrument errors  -  Manufacture  -  Mechanisms  -  Models  -  Multipurpose robots  -  Robot programming  -  Robots  -  Sensitivity analysis

Uncontrolled terms: Analysis and verifications  -  Error sensitivity  -  Error sensitivity analysis  -  Experimental prototype  -  Manufacturing tolerances  -  Planar parallel mechanisms  -  Positional accuracy  -  Sensitivity evaluation

Classification code: 537.1 Heat Treatment Processes  -  601.3 Mechanisms  -  731.5 Robotics  -  921 Mathematics

Numerical data indexing: Size 1.00e-03m, Size 1.80e-04m to 3.00e-04m, Size 4.00e-04m to 1.00e-03m

DOI: 10.11975/j.issn.1002-6819.2019.06.005

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

35. Design and test of single row sweet potato vine recycling machine

Accession number: 20192307005263

Title of translation:

Authors: Zheng, Wenxiu (1); Lü, Zhaoqin (1, 2); Zhang, Wanzhi (1); Liu, Zhengduo (1); Lu, Yao (1); Li, Yudao (1)

Author affiliation: (1) College of Mechanical and 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: Lü, Zhaoqin(lzqsdau2003@126.com)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 1-9

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Sweet potato is an important raw material for food, feed, industrial, it also is a high quality anti-cancer health food and new energy material. It is widely cultivated in the world, and China is the largest producer of sweet potato in the world, the average perennial planting area of sweet potato is more than 3 million hm2, accounting for about 45% of the global planting area of sweet potato. The yield of sweet potato vine is generally more than 2×104 kg/hm2, and the sweet potato vines is rich in nutrients and is an ideal feed material. The sweet potato vines grow vigorously along the ground surface, and the vines are intertwined between the ridges, it is difficult to collect the vines mechanically. Sweet potato harvest mainly includes cleaning the vines and breaking the ridge to harvest, the treatment of vines before harvest has great influence on its harvest efficiency, labor intensity and yield. At present, the collecting mechanization of sweet potato vine in China is almost blank, which seriously restricts the development of sweet potato industry. Cleaning up the vines by hand is a labor intensive and low work efficiency work, which seriously restricts the enthusiasm of farmers in production. At present, the main problem of sweet potato vine treatment machinery at home and abroad is that the vines are crushed and scattered in the field, so the sweet potato vines cannot be collected and used as feed or energy, thus causing greater economic losses and easily aggravating the spread of diseases and insect pests. Aiming at the difficulty that the sweet potato vines can only be harvested by hand, a kind of single row sweet potato vine recycling machine matched with a small four-wheeled tractor was designed. Through theoretical analysis and experiment, the structure and working principle of the recycling machine were analyzed, and key components such as cutting device, vine picking device and feeding device were design. Using Box-Behnken experimental design method, quadratic regression models with the vine collected rate, the vine stubble height, the sweet potato injury rate as the response indexes were established. Through the analysis of model interaction and response surface, the change laws of the influence of cutter roller speed, the forward speed of machine and the ground clearance on the response indexes were obtained. The regression model was optimized by Design-Expert8.0 software, and the accuracy of the predicted results was verified by experiments. The relative error between the measured value and the predicted value was less than 5%, indicating that the model was high reliability. The order of significance of each factor on the vine collected rate was the forward speed of machine, cutter roller speed and ground clearance, the order of significance of each factor on the vine stubble height was the ground clearance, cutter roller speed and forward speed of machine, the order of significance of each factor on the sweet potato injury rate was the ground clearance, cutter roller speed and forward speed of machine. The optimal working parameters were that the cutter roller speed was 2 000 r/min, the forward speed of machine was 2.5 km/h and the ground clearance was 15 mm. Under the condition of optimum working parametersthe vine collected rate was 93.16%, the vine stubble height was 33.8 mm, and the sweet potato injury rate was 0.26%, the working effect was better. The research results are of great significance in promoting the development of light and simplified production of sweet potato industry. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 31

Main heading: Design of experiments

Controlled terms: Agricultural machinery  -  Design  -  Diseases  -  Experiments  -  Harvesting  -  Losses  -  Machine design  -  Recycling  -  Regression analysis  -  Rollers (machine components)   -  Speed

Uncontrolled terms: Box-Behnken experimental design  -  Design and tests  -  Ground clearance  -  Model interaction  -  Quadratic regression  -  Spread of disease  -  Sweet potato  -  Working parameters

Classification code: 452.3 Industrial Wastes  -  601 Mechanical Design  -  601.2 Machine Components  -  821.1 Agricultural Machinery and Equipment  -  821.3 Agricultural Methods  -  901.3 Engineering Research  -  911.2 Industrial Economics  -  922.2 Mathematical Statistics

Numerical data indexing: Percentage 2.60e-01%, Percentage 4.50e+01%, Percentage 5.00e+00%, Percentage 9.32e+01%, Rotational_Speed 2.00e+03RPM, Size 1.50e-02m, Size 3.38e-02m, Velocity 6.95e-01m/s

DOI: 10.11975/j.issn.1002-6819.2019.06.001

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

36. Evaluation of production efficiency and sustainability for straw-sheep-cropland recycling agroecosystems based on emergy analysis

Accession number: 20192307005291

Title of translation: --

Authors: Zhu, Bingying (1); Dong, Jia (1); Shen, Mingxing (2); Zheng, Jianchu (3)

Author affiliation: (1) College of Humanity and Development, Nanjing Agricultural University, Nanjing; 210095, China; (2) Institute of Agricultural Sciences in Taihu Lake Regions of Jiangsu Province, Suzhou; 215155, China; (3) Center of Circular Agriculture, Jiangsu Academy of Agricultural Sciences, Nanjing; 210095, China

Corresponding author: Zheng, Jianchu(zjc@jaas.ac.cn)

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 235-243

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Ecological recycling agriculture is an effective practice to solve the pollution from large-scale livestock farming. This study evaluated the production efficiency and sustainability of the straw-sheep-cropland integrated agroecosystem. This integrated system included four subsystems, as the sheep raising subsystem, the organic composting subsystem, the cropping subsystem and the feed producing subsystem. For the sheep raising subsystem, the emergy input of renewable resources was 2.33×1012 Sej, accounting for 15 Sej, accounting for 0.24%; the purchased economic resource emergy was 4.03×1018 Sej, accounting for 99.76%, in which feed and labor were two main components, with a proportion of 84.22% and 10.06% respectively. The emergy output of the sheep husbandary subsystem was 2.65×1019 Sej, including the sheep and manure, accounting for 17.70% and 82.30% respectively. For the organic composting subsystem, the emergy input of renewable resources was 7.69×1012 Sej, accounting for 19 Sej, accounting for >99.90%; in which the raw materials for producing organic fertilizers accounted for the most, including the manure and straw residues with a proportion of 89.31% and 8.81% respectively. The emergy output for the organic compost subsystem was 2.06×1019 Sej, including two sections with equal proportion, one for inside using and the other for outside selling. For the cropping subsystem, the emergy input of renewable resources was 1.12×1017 Sej, accounting for 6.16%; the non-renewable resource emergy input was 7.06×1015 Sej, accounting for 0.38%; the purchased economic emergy was 1.46×1018 Sej, accounting for 93.46%, in which the chemical fertilizer, labor, electricity, machinery and diesel were the main components with a proportion of 33.60%, 26.86%, 15.99%, 12.78% and 8.61%, respectively. The emergy output was 2.57×1018 Sej, including two parts, grain accounted for 54.08% and straw residues accounted with 45.91%. For the feed-production subsystem, the renewable resource emergy input was 1.95×1013 Sej, accounting for 19 Sej, accounting for >99.99%, in which the soybean meal and straw residues were two main components, with a proportion of 20.31% and 50.32%, respectively. The only emergy output was feed of 2.11×1019 Sej, with two parts with the inside using of 16.13% and outside selling of 83.87%. Results of evaluation for the integrated system showed that the unit emergy value (UEV) was reduced by 96.09%, which was suggested that the emergy use efficiency was greatly increased comparing to the single sheep husbandry. The emergy investment ratio (EIR) and environment loading ratio (ELR) were decreased by >67.66%, respectively, while the emergy sustainability index (ESI) was evidently enhanced, suggesting that the integrated agroecosystem has a good sustainable potential with low environmental pressure. However, the net emergy yield ratio (EYR) and emergy yield-investment ratio were decreased by 70.32% and 70.43%, respectively, suggesting that the production efficiency and economic benefit were reduced in the integrated agroecosystem. This was caused by increasing cost from raw materials (i.e. bean dregs or straw residues), buildings and equipment. Therefore, the ecological compensation is needed for the positive externality of ecosystem services from the integrated agroecosystem. The compensation standard was estimated as 380.76/sheep per year based on the net emergy benefit difference. Nonetheless, once the current integrated system is optimized, EYR will be increased in theory and the integrated system can achieve self-compensation for its positive environmental benefits. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 29

Main heading: Ecosystems

Controlled terms: Agriculture  -  Composting  -  Economics  -  Efficiency  -  Fertilizers  -  Integrated control  -  Machinery  -  Manures  -  Recycling  -  Sales   -  Straw  -  Sustainable development

Uncontrolled terms: Agro ecosystems  -  Compensation standards  -  Ecological compensation  -  Emergy evaluation  -  Emergy investment ratio  -  Environmental benefits  -  Environmental pressures  -  Production efficiency

Classification code: 452.3 Industrial Wastes  -  454.3 Ecology and Ecosystems  -  731.1 Control Systems  -  804 Chemical Products Generally  -  821 Agricultural Equipment and Methods; Vegetation and Pest Control  -  821.5 Agricultural Wastes  -  913.1 Production Engineering  -  971 Social Sciences

Numerical data indexing: Percentage 1.01e+01%, Percentage 1.28e+01%, Percentage 1.60e+01%, Percentage 1.61e+01%, Percentage 1.77e+01%, Percentage 2.03e+01%, Percentage 2.69e+01%, Percentage 3.36e+01%, Percentage 4.59e+01%, Percentage 5.03e+01%, Percentage 5.41e+01%, Percentage 7.03e+01%, Percentage 7.04e+01%, Percentage 8.23e+01%, Percentage 8.39e+01%, Percentage 8.42e+01%, Percentage 8.61e+00%, Percentage 8.81e+00%, Percentage 8.93e+01%, Percentage 9.35e+01%, Percentage 9.61e+01%, Percentage 9.98e+01%

DOI: 10.11975/j.issn.1002-6819.2019.06.029

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

37. Soybean field weed recognition based on light sum-product networks and UAV remote sensing images

Accession number: 20192307005272

Title of translation:

Authors: Wang, Shengsheng (1); Wang, Shun (2); Zhang, Hang (2); Wen, Changji (3)

Author affiliation: (1) College of Computer Science and Technology, Jilin University, Changchun; 130012, China; (2) Software Institute, Jilin University, Changchun; 130012, China; (3) College of Information and Technology, Jilin Agricultural University, Changchun; 130118, China

Source title: Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Abbreviated source title: Nongye Gongcheng Xuebao

Volume: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 81-89

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: In weed control, using unmanned aerial vehicle (UAV) to obtain images, spraying specific pesticides according to different weed communities is an effective means of prevention and control. Sum-product networks is suitable for small embedded devices such as UAV. But it has many parameters, long training time, and more redundant nodes and subtrees in the image classification task, so that the recognition accuracy is not high. In response to these problems, this paper improved the learning process of traditional sum-product networks and used a mini-batch learning method to construct a network model through one pass of data. Its lightweight structure required less hardware resources and was more suitable for small embedded devices such as drones. It had reference significance for the subsequent spraying of pesticides by drones. For the input image, the light sum-product networks weed recognition model first used K-means clustering as the low-level feature extractor to obtain the feature dictionary, then downsampled the extracted features, and took the sampling features into mini-batches of data as input to train the light sum-product networks. Each category corresponds to an independent network structure, and the high-level features were extracted by internal nodes in the network structure. The probability values of the corresponding categories were output by the root nodes to identify weeds. The network structure was updated by comparing the correlation coefficients between variables. Bayesian moment matching was used to update the network parameters. To simplify the structure, when a product node had only one child, it was removed from the network, and its child nodes were connected to its parent node. Similarly, if a sum node was the last node of another sum node, then the child node was deleted and all its child nodes were promoted one layer up. This effectively reduced redundant edge branches and made the model structure lighter. Using this method, the average classification accuracy of soybean seedlings, grass weeds, broadleaf weeds and soils in UAV images was 99.5%, and the average sensitivity was 99.6%. And the model parameter quantity was only 33% of the traditional sum-product networks. The parameter quantity would increase with the input of the data flow. The amount of parameters was still much smaller than traditional convolutional neural networks AlexNet when using the larger data sets to construct the light sum-product networks. It showed that the model was suitable for larger data sets. The memory usage was reduced by 549 M compared to the traditional sum-product networks and was reduced by 1 072 M compared to the convolutional neural networks. The maximum average training time was reduced by 688.79 s compared to the traditional sum-product networks, which was much less than the convolutional neural networks. The experimental results showed that using the light sum-product network as the weed recognition model, the model parameters were less, the memory requirements were lower, and the training time was shorter without loss of precision. The shortcoming was that the data acquired by the UAV image in the previous stage needed to be processed in multiple steps. The data set itself relied on manual classification. Some images had different categories of overlap, and the misclassification of such images would increase when the features were extracted. However, by adjusting the classification threshold, the overall classification can achieve the desired results. The research can provide a reference for the use of light sum-product networks in weed recognition of UAV spraying pesticides. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 39

Main heading: Image classification

Controlled terms: Antennas  -  Classification (of information)  -  Convolution  -  Distributed computer systems  -  Drones  -  Image coding  -  Image segmentation  -  K-means clustering  -  Learning systems  -  Neural networks   -  Pesticides  -  Remote sensing  -  Unmanned aerial vehicles (UAV)  -  Weed control

Uncontrolled terms: Parameter learning  -  Recognition  -  Structure-learning  -  Sum product  -  Weed

Classification code: 652.1 Aircraft, General  -  716.1 Information Theory and Signal Processing  -  722.4 Digital Computers and Systems  -  803 Chemical Agents and Basic Industrial Chemicals

Numerical data indexing: Percentage 3.30e+01%, Percentage 9.95e+01%, Percentage 9.96e+01%

DOI: 10.11975/j.issn.1002-6819.2019.06.010

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village

 

38. Dynamic performance coordination control of hydraulic electrical energy-regenerative suspension based on road excitation self-adaptation

Accession number: 20192307005269

Title of translation:

Authors: Wang, Ruochen (1); Ding, Yanshu (1); Sun, Dong (1); Ding, Renkai (1); Meng, Xiangpeng (1)

Author affiliation: (1) School of Automobile and Traffic 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: 35

Issue: 6

Issue date: March 15, 2019

Publication year: 2019

Pages: 55-64

Language: Chinese

ISSN: 10026819

CODEN: NGOXEO

Document type: Journal article (JA)

Publisher: Chinese Society of Agricultural Engineering

Abstract: Compared with the passive suspension, the hydraulic electrical energy-regenerative suspension can not only recycle the energy dissipated by the suspension, but also improve the dynamic performance of vehicle, which has attracted extensive attention of scholars at domestic and abroad. However, the most of research focuses on the analysis of energy-feedback characteristics,without considering how to improve the dynamic performance of vehicles adaptively according to complex road conditions while restoring energy considered. In addition, the ride comfort and handling stability of vehicle are mutually constrained, and the contradiction between them is still prominent under the passive mode. In order to meet the optimal performance of hydraulic electrical energy-regenerative suspension during the global operating condition, a hydraulic electrical energy-regenerative suspension with 3 working modes focusing on comfort, sport and comprehensiveness modes was designed to regenerate vibration energy while improving the ride comfort and handling stability of the vehicle in this paper. The road excitation frequency was chosen as the suspension mode switching threshold. The hydraulic electrical energy-regenerative shock absorber was composed of a hydraulic cylinder, a hydraulic rectifier bridge, a hydraulic motor, 2 accumulators, the hydraulic pipeline, a rotary motor, etc., wherein the hydraulic rectifier bridge consisted of 4 one-way valves. The DC-DC converter was introduced into the suspension energy-regenerative circuit. Based on this, the damping force formula of the shock absorber was derived. The double loop semi-active control scheme consisting of skyhook-groundhook control and fuzzy PID control was designed. The semi-active control of the hydraulic electrical energy-regenerative suspension was achieved based on the energy-regenerative circuit. The DC-DC converter could work in both boost and buck modes. The duty cycle of the MOS tube switching signal in the DC-DC converter was adjusted real time to change the damping force of the damper. Moreover, the Kalman Filter algorithm was introduced to accurately obtain the suspension state variables to track the ideal damping force. The first-order zero-crossing detection method was introduced to identify the main frequency of the road input, which was used as the switching threshold of each suspension working mode. The simulation results showed that the hydraulic electrical energy-regenerative semi-active suspension could switch the working mode adaptively according to the road frequency, and improve the vehicle dynamic performance effectively than the single mode control of semi-active suspension while regenerating energy. The proposed hydraulic electrical energy-regenerative suspension combined with road frequency self-adaption could coordinate suspension dynamic performance with energy-regenerative characteristics. The vehicle body acceleration in the comfort mode was reduced by 13.75% compared with that of the single mode control suspension, and the tire dynamic load was reduced by 17.76% in the sport mode. To verify the effectiveness of the simulation, a bench test was performed. The deviations of the PTP(peak-to-peak) value of test and simulation data of vehicle body acceleration were 1.36%, 15.72%, 4.86%, and 13.6%, respectively, and the ones of the tire dynamic load were 9.34%, 13.62%, 7.82%, and 15.47%, respectively. The errors between the test and simulation results was within 16%, which verified the correctness of the simulation results and the feasibility of the semi-active suspension system. The study provides an important reference for the performance upgrade of the hydraulic electrical energy-regenerative suspension. © 2019, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.

Number of references: 32

Main heading: Suspensions (components)

Controlled terms: Active suspension systems  -  Automobile bodies  -  Automobile suspensions  -  Control engineering  -  Damping  -  DC-DC converters  -  Dynamic loads  -  Electric inverters  -  Electric rectifiers  -  Hydraulic accumulators   -  Hydraulic motors  -  Mechanisms  -  Rectifying circuits  -  Roads and streets  -  Shock absorbers  -  Sports  -  Suspensions (fluids)  -  Switching  -  Three term control systems  -  Vehicle performance   -  Vehicles  -  Vibrations (mechanical)

Uncontrolled terms: Double-loop  -  Electrical energy  -  Kalman filter algorithms  -  Multimodes  -  Self adaption  -  Semi-active suspension systems  -  Vehicle dynamic performance  -  Zero-crossing detection

Classification code: 406.2 Roads and Streets  -  408.1 Structural Design, General  -  461.3 Biomechanics, Bionics and Biomimetics  -  601.2 Machine Components  -  601.3 Mechanisms  -  632.2 Hydraulic Equipment and Machinery  -  662.1 Automobiles  -  662.4 Automobile and Smaller Vehicle Components  -  704.1 Electric Components  -  731.1 Control Systems  -  804 Chemical Products Generally  -  931.1 Mechanics

Numerical data indexing: Percentage 1.36e+00%, Percentage 1.36e+01%, Percentage 1.38e+01%, Percentage 1.55e+01%, Percentage 1.57e+01%, Percentage 1.60e+01%, Percentage 1.78e+01%, Percentage 4.86e+00%, Percentage 7.82e+00%, Percentage 9.34e+00%

DOI: 10.11975/j.issn.1002-6819.2019.06.007

Compendex references: YES

Database: Compendex

Compilation and indexing terms, Copyright 2019 Elsevier Inc.

Data Provider: Engineering Village