<RECORD 1>
Accession number:20154301434115
Title:Extraction of biological electric shock signal instantaneous amplitude and frequency based on local mean decomposition
Authors:Han, Xiaohui (1); Du, Songhuai (1); Su, Juan (1); Liu, Guangeng (1)
Author affiliation:(1) College of Information and Electrical Engineering of China Agricultural University, Beijing, China
Corresponding author:Du, Songhuai
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:221-227
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to quickly and accurately extract the electrical parameters in the transient signal of the electric shock caused by organisms, an instantaneous amplitude and frequency extraction method based on local mean decomposition (LMD) for the total leakage current signal of biological electric shock was proposed. The de-noising total leakage current signal was decomposed into a linear combination of a finite set of product functions (PF) and the amplitude modulated (AM) signal, and frequency modulated (FM) signal of each PF also could be obtained. The amplitude modulated signal was utilized to calculate the instantaneous amplitude and damping, while the frequency modulated signal was used to determine the instantaneous frequency. By using the method, compared with the Hilbert-Huang Transformation (HHT), the curves of the instantaneous amplitude had less distortion in wave head and the instantaneous frequency had shorter swings. The method of HHT consisted of separation of the series data to components with different time scale (e.g. intrinsic mode function (IMF)), and empirical mode decomposition (EMD), and application of the Hilbert Transformation to obtain the instantaneous amplitude and frequency of the signal from the IMF. The results of simulation signal showed that LMD and EMD were carried out on the test signal which was three PF components and five IMF components, respectively. The energy change values of LMD and EMD before and after decomposition was 0.2851, 0.5633, and the decomposition time of LMD was shorter than the EMD. Moreover, the instantaneous amplitude frequency based on the calculation of HT and integrated algorithm of PF appear the phenomenon of flying wings, but compared with the Hilbert transform, the proposed method to calculate the result was more smooth which can restrain endpoint effect to a certain extent and extract the instantaneous amplitude and frequency better. Experimental signal analysis results showed that LMD and EMD were carried out on the de-noising total leakage current signal which received five PF components and six IMF components, respectively, and the energy change values of LMD and EMD before and after decomposition were 0.5574, 0.8896, and the use of decomposition time were 0.0835s, 0.2479s, respectively. In calculating the instantaneous frequency aspects, the moment of electric shock can be determined by the LMD, while the instantaneous frequency was calculated by using the Hilbert transform not only unable to determine the electric shock time, but also the negative frequency values appeared, which had no physical meaning. In calculating the instantaneous amplitude aspects, the average instantaneous amplitude of the total leakage current signal before the electric shock was 11.3240 mA, compared with the real amplitude, the absolute error was 0.0298 mA, while the error was obtained by using Hilbert transform was 1.0190 mA. In addition, the absolute errors between the average instantaneous amplitude of total leakage current signal after electric shock was computed by LMD and Hilbert Transform methods and real amplitude were 0.4340 mA, 0.6643 mA, respectively. Therefore, it can be seen that the simulation and experimental results prove the feasibility and effectiveness of the proposed method. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Signal processing
Controlled terms:Amplitude modulation - Electric fault currents - Errors - Extraction - Fault detection - Frequency modulation - Hilbert spaces - Leakage currents - Mathematical transformations - Metadata - Signal analysis - Signal denoising
Uncontrolled terms:Amplitude modulated signals - Empirical Mode Decomposition - Frequency modulated signal - Hilbert Huang Transformation - Instantaneous parameter - Local mean decomposition (LMD) - Local mean decompositions - Organisms electric-shocking
Classification code:701.1 Electricity: Basic Concepts and Phenomena - 716.1 Information Theory and Signal Processing - 802.3 Chemical Operations - 921 Mathematics - 921.3 Mathematical Transformations
DOI:10.11975/j.issn.1002-6819.2015.17.029
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 2>
Accession number:20154301434094
Title:Influences of bead structure parameters on contact pressure distribution of mechanical elastic wheel
Authors:Fu, Hongxun (1); Zhao, Youqun (1); Lin, Fen (1); Du, Xianbin (1); Wang, Qiang (1); Zhu, Mingmin (1)
Author affiliation:(1) College of Energy and Power Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing, China
Corresponding author:Zhao, Youqun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:57-64
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Non-pneumatic safety tires have been introduced with a new type of elastomer, which functions as the air of the pneumatic tire. It appears to have advantages over the pneumatic tire in terms of flat proof and maintenance free. As the pursuing of consumer on car safety, handling stability and comfort continue to enhance, the study of the non-pneumatic tire is also growing. The mechanical elastic wheel is a kind of non-pneumatic tire. A mechanical elastic wheel with a non-pneumatic elastic outer ring which functions as the air of the pneumatic tire was presented to reduce the risk of puncturing, and its loading mode and contact behaviors were different from the pneumatic tire. In this paper, the influences of bead structure parameters on contact pressure distribution of mechanical elastic wheel were investigated to provide certain guidance for optimizing the mechanical contact characteristics of the mechanical elastic wheel. First of all, the Timoshenko circle curved beam model of the bead was established to describe the deformation characteristics of wheel bearing. Through the theoretical analysis of wheel bearing deformation, the main structural parameters affecting the mechanical elastic wheel contact behaviors were found, which contained bead section ratio, elastic ring section ratio and elastic ring distribution coefficient. Secondly, different bead structure parameters were put forward, and the three-dimensional finite element (FE) models of the corresponding mechanical elastic wheel were developed. The model of mechanical elastic wheel consisted of a thin flexible annular outer ring and hinge units that connected the outer ring with a rigid hub. To establish the FE model, various nonlinear factors, such as the geometrical nonlinearity, the material nonlinearity and the contact nonlinearity, were considered comprehensively. In order to prove the validity of the FE model, the load characteristic test of the mechanical elastic was conducted by tire test-bed. Finally, the commercial FE software ABAQUS was used to conduct static load simulation test for the mechanical elastic wheel, the test results were analyzed and the influence of bead structure parameters on the wheel contact behaviors was revealed. In addition, to scientifically evaluate the contact behaviors of the mechanical elastic wheel, evaluation indices of contact behaviors were introduced. The major findings are obtained as follows: 1) there is a positive correlation between bead section ratio and vertical stiffness of the mechanical elastic wheel, so is elastic ring section ratio; there is a negative correlation between elastic ring distribution coefficient and vertical stiffness. 2) the contact pressure distributions of the wheel with different bead structural parameters are similar, the shape of contact mark is approximately rectangle, the pressure of the center contact region is the largest and the pressure reduces gradually from center to edge, and the minimum appears on the regional edge. 3) reducing bead section ratio, elastic ring section ratio or elastic ring distribution coefficient, the wheel contact length and the contact area increase, and the average value and the skewness of contact pressure decrease, which would improve the performance of contact behaviors of the mechanical elastic wheel at different degrees, thereby improve the wheel gripping, driving and braking performance, the average abrasion performance, and so on. Through the study, we found that on the basis of meeting the requirement of vertical stiffness, the bead structure parameters could be appropriately adjusted when optimizing the structure of mechanical elastic wheel, so as to improve the wheel contact performance. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Wheels
Controlled terms:ABAQUS - Bearings (machine parts) - Braking performance - Computer software - Curved beams and girders - Deformation - Finite element method - Function evaluation - Models - Pneumatics - Pressure distribution - Safety engineering - Software testing - Stiffness - Tires
Uncontrolled terms:Contact behavior - Curved beams - Elastic wheels - Non-pneumatic tires - Structure parameter
Classification code:408.2 Structural Members and Shapes - 601.2 Machine Components - 632.3 Pneumatics - 662.1 Automobiles - 723 Computer Software, Data Handling and Applications - 723.5 Computer Applications - 818.5 Rubber Products - 914 Safety Engineering - 921.6 Numerical Methods - 931.1 Mechanics - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2015.17.008
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 3>
Accession number:20154301434088
Title:Design and experiment of archimedes spiral type stubble breaking ditching device and stubble breaking anti blocking device
Authors:Lin, Jing (1); Li, Baofa (1); Li, Hongzhe (2)
Author affiliation:(1) College of Engineering, Shenyang Agricultural University, Shenyang, China; (2) Agricultural Mechinery Extended Station of Tieling County, Tieling, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:10-19
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Today, ridge tillage method is an effective farming method that can resist the drought and flood in the northeast area of China. Because of the climate and natural conditions, most of the northeast area of China will continue to adopt ridge tillage method. In the case of ridge planting, no-till can improve the ground temperature, and can control the summer flood and drainage. In recent years the strip rotary tillage type no tillage planter has been extended. Because of the rotary tillage, the root stubble is broken and the anti-blocking performance is good. However, the soil tillage intensity is between 6.5 and 7.8, and the tillage destroys the original ridge, and forms the new ditch. At present, the number of no tillage finger clip type precision seeding and fertilizing machine applied in the production, is about 3000 in the northeast area of China, and the soil tillage intensity index is 1, which reduces the soil tillage intensity and produces no new ditch; but the two-row machine has the complete machine weight of 1000 kg, which brings too large compaction on soil, and makes ridge stand almost flat, therefore, wheel rut compaction seriously affects maize root growth. This machine not only loses the advantage of ridge planting, increases soil hardness, but also enhances manufacturing cost, and makes the price per machine high. The cost of the field operation is greatly improved, which does not accord with the requirements of energy saving and emission reduction in agricultural production. For no tillage planter, the current problem is the existence of the problem remains a ridge shape. Aiming at the requirement of researching and developing new no tillage planter for the conservation tillage corn ridge agricultural technology in the northeast area in China, based on the Archimedes spiral theory, this paper analyzes the notched disc knife break crop performance and the technical requirements to stubble breaking cutter for ideal seed bed, optimizes the spiral notched disk break stubble cutter structure and carries out the optimal selection of parameter; and develops the stubble breaking ditching device and stubble breaking anti-blocking device. Through test verification of stubble breaking ditching device, it opens a "V"-shape groove, and 2 pieces of spiral-notch disc cutters have a diameter of 350 mm, when sowing depth is 40 mm, sowing and ditching width is 28 mm. Increasing the weight makes the stubble breaking ditching device achieve a weight of 100 kg, and in the area implementing high stubble conservation tillage mode and with a field coverage rate of 30%, stubble breaking ditching device can be adopted instead of the conventional planter seeding furrow opener, and ordinary seeder can realize no tillage planting. When stubble breaking anti-blocking device's breaking stubble depth is between 70 and 100 mm, ditching width is 40-50 mm, and ridge cleaning width of ridge cleaning parts is 210 mm, which are up to the requirement of agricultural technology. Increasing the weight makes the monolithic disc broken stubble device achieve a weight of 113 kg in the area implementing conservation tillage of high stubble breaking rod cover mode and with covering rate of 1 kg/m<sup>2</sup>, stubble breaking anti-blocking device can be adopted, and ordinary seeder can realize no tillage planting. In this paper, the development of the rolling disc coulter and its edge is Archimedes spiral gap, after test for many times, stubble cutting resistance is small, the weight of machines can be reduced, because it is a passive anti-blocking device, keeping the shape of ridge. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:38
Main heading:Agricultural machinery
Controlled terms:Agriculture - Compaction - Costs - Cultivation - Design - Disks (machine components) - Emission control - Energy conservation - Floods - Machine design - Machinery - Optimization - Seed - Soil conservation - Soils - Structural optimization
Uncontrolled terms:Agriculture machinery - Disc cutter - Spiral of archimedes - Structure optimization - Stubble breaking anti blocking device - Stubble breaking ditching device
Classification code:451.2 Air Pollution Control - 483.1 Soils and Soil Mechanics - 525.2 Energy Conservation - 601 Mechanical Design - 601.2 Machine Components - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 911 Cost and Value Engineering; Industrial Economics - 921.5 Optimization Techniques
DOI:10.11975/j.issn.1002-6819.2015.17.002
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 4>
Accession number:20154301434097
Title:Accelerative effect of fertigation on emitter clogging by muddy water irrigation
Authors:Li, Kangyong (1); Niu, Wenquan (1, 2); Zhang, Ruochan (1); Liu, Lu (2, 3)
Author affiliation:(1) College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, China; (2) Institute of Soil and Water Conservation, Northwest A&F University, Yangling, China; (3) BaojiUniversity of Arts and Sciences, Baoji, China
Corresponding author:Niu, Wenquan
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:81-90
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Integrated drip irrigation and fertilizer technology develops rapidly due to its advantages of high efficiency, water saving, ability to adapt to the terrain and so on, but fertilizer may cause the clogging of drip emitter, which draws much attention. In order to explore the influence of fertilizer on emitter clogging in the process of fertigation, a periodic intermittent experiment was carried out. Three particle gradations and four fertilizer concentrations (0, 0.4, 0.6, and 1.2 g/L) were desgined. The drip irrigation with fertilizer and muddy water of different particle gradations as conducted for 30 min each time under working pressure of 40 kPa. After 4 hours, the irrigation was redone. Then the relative flow rate of emitter and its uniformity were determined. After the experiment, the clogging positions of emitters were recorded. The drip tape was air-dried for 4 months for measurements of clogging status. The complete clogged emitters were used for observation by field emission scanning electron microscopy (FESEM) to analyze the structure and composition of the blockage. The results demonstrated that fertigation had an obvious acceleration effect on emitter clogging, and effect was more obvious in fertilizer solution with high concentration. When the application rate of fertilizer was 1.2 g/L, the effective irrigation times of muddy water with 3 different particle gradations decreased by 36.4%, 77.8% and 78.8% respectively; when the application rate of fertilizer was 0.4 g/L, the effective irrigation times of muddy water with 3 different particle gradations decreased by 9.1%, 33.3% and 14.3% respectively. The acceleration effect of fertilizer application on emitter was most non-obvious when the concentration of fertilizer solution was less than 0.4 g/L. The acceleration effect of fertilizer on emitter clogging was influenced by particle gradation. As for the drip tap selected in the test, the acceleration effect was more obvious in particles with dominated by 0.034-0.067 mm. Without fertilization, the particle gradation B with content of 0.034-0.067 mm particles higher than 50% was the easiest to cause clogging, followed by particle gradation A with content of 0-0.034 mm particles larger than 50%, and the particle gradation C with content of 0.067-0.1 mm particles larger than 50% was the least to cause clogging. Complete clogging was mainly in A and B particle gradation, while partial clogging was mainly in C. Fertilizer enhanced the flocculation of particles in muddy water and promoted the formation of stable and compact aggregates, which was the major cause of acceleration effect of emitter clogging. After fertigation, the surface structure of blockage was more complicated, the gap of aggregates decreased. Fertigation had little effects on clogging location and composition of blockage. The effect of fertilizer on clogging position and the main ingredient of the blockage were not obvious. After fertigation, the ratio of complete clogging to partial clogging in the 3 particle gradation increased. Compared to no fertilization, fertigation caused that the ratio of complete clogging to total clogging of emitters increased from 54% to 86.11%, and the ratio of complete clogging emitters to total tested emitters also increased from 26.67% to 34.44%. Fertigation did not change the gathering position of the blockage in emitters. The ratio of emitter import clogging to emitter channel clogging was 2.10 with fertigation, and 2.20 without fertigation. This research provides valuble information for the application and promotion of integrated drip irrigation and fertilizer technology. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:35
Main heading:Agglomeration
Controlled terms:Acceleration - Aggregates - Fertilizers - Field emission microscopes - Irrigation - Scanning electron microscopy - Sediments - Water conservation
Uncontrolled terms:Acceleration effects - Application rates - Clogging - Clogging type - Emitter clogging - Fertilizer applications - Field emission scanning electron microscopy - Working pressures
Classification code:406 Highway Engineering - 444 Water Resources - 483 Soil Mechanics and Foundations - 741.3 Optical Devices and Systems - 802.3 Chemical Operations - 804 Chemical Products Generally - 821.3 Agricultural Methods
DOI:10.11975/j.issn.1002-6819.2015.17.011
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 5>
Accession number:20154301434121
Title:Response of grain yield in Tibet to climate and cultivated land change during 1985-2010
Authors:Yang, Chunyan (1, 2); Shen, Weishou (3); Li, Haidong (3)
Author affiliation:(1) School of Information & Control, Nanjing University of Information Science & Technology, Nanjing, China; (2) Jiangsu Engineering Research Center on Meteorological Energy Using and Control, Nanjing, China; (3) Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing, China
Corresponding author:Shen, Weishou
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:261-269
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With less cultivated land, and sensitive to climate change, grain yield of Tibet is low and unstable, which has become an important factor to affect the social and economic development. In this study, the relationship between Tibet's grain yield and cultivated land during 1985-2010 were analyzed to find the main factors affecting grain yield in the background of climate warming, and the countermeasures and suggestions were put forward to guarantee of grain production in Tibet. Meteorological data were from 38 weather stations in Tibet, grain yield was from 2011 Tibet Automatic Yellow Book, and cultivated land area was from the remote sensing images from multi spectral scanner in 1980, thematic mapper in 1990, enhanced thematic mapper in 2000, and HJ-satellite in 2010. The four series of remote sensing data were corrected before use. In order to reveal the changes and influencing factors of grain yield, the crop climatic potential productivity was calculated by using Thornth waite model, and the crop trend production and climate production were separated by exponential curve based on the grain production and the meteorological data and four series of remote sensing data. The trend of climate change was analyzed using climatic trend rate and accumulative anomaly method. With the aid of visual interpretation and land change rate, changes of cultivated land were also discussed. The relationship between grain yield and climate change and the change of cultivated land was explored systematically using grey correlation analysis method. The results showed that: 1) From 1985 to 2010 in Tibet, the average total grain production was 77.83×107 kg, while average climatic potential productivity and grain production per unit area was 7419.58 kg/(hm<sup>2</sup>·a) and 1948.93 kg/hm<sup>2</sup>respectively; Tibet's total grain production, climatic potential productivity and grain production per unit area demonstrated a fluctuating growing trend during the period of 1985-2010; Grain production potential was achieved in an average rate of 25.86%, presenting a gradually increasing trend; Grain production was approaching climatic potential productivity and there was much space for improvement in it; 2) The ratio of climate production to grain production per unit area fluctuated between -10.74% and 8.03% and its variation range showed a decreasing trend while the influence on grain production by climate continued to decline; 3) The average accumulated temperature ≥0 in Tibet was 2224.53 , mean temperature in growing season and precipitation changes were 11.41 and 387.48 mm, respectively, which showed an increasing trend, while average sunshine hours of growing season was 1095.45 h, which tended to decrease; Besides, the turning change of those climate factors appeared in 1994; and 4) Correlation degree between grain production and cultivated land, accumulated temperature ≥0 and precipitation changed from 0.633 to 1.321; Correlation degree between grain production and mean temperature in growing season and precipitation was 0.595 and 0.641. Cultivated land, accumulated temperature ≥0 and precipitation in growing season were the most important factors affecting food production. The research can provide valuble information for identification of grain yield and its influencing factors, and to further improve the grain yield and to ensure the sustainable development of social economy in Tibet. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Climate change
Controlled terms:Climate models - Correlation methods - Crops - Cultivation - Economic and social effects - Economics - Grain (agricultural product) - Image reconstruction - Land use - Meteorology - Productivity - Remote sensing - Space optics
Uncontrolled terms:Accumulated temperatures - Changes of cultivated lands - Cultivated lands - Enhanced thematic mappers - Grey correlation analysis - Grey correlation analysis methods - Social and economic development - Tibet Plateau
Classification code:403 Urban and Regional Planning and Development - 443 Meteorology - 443.1 Atmospheric Properties - 656.1 Space Flight - 821.3 Agricultural Methods - 821.4 Agricultural Products - 921 Mathematics - 922.2 Mathematical Statistics - 971 Social Sciences
DOI:10.11975/j.issn.1002-6819.2015.17.035
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 6>
Accession number:20154301434091
Title:Optimal operation for large pumping station system based on water transferring losses of river
Authors:Feng, Xiaoli (1); Qiu, Baoyun (1)
Author affiliation:(1) School of Hydraulic, Energy and Power Engineering, Yangzhou University, Yangzhou, China
Corresponding author:Qiu, Baoyun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:35-41
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:A large amount of energy is consumed during the pumping station operation, especially for the pumping station that water level of the forebay varied frequently in a wide range, pump units often run deviating from the high efficient area of pump, this results in energy waste. In order to lift water, some energy dissipation devices and flow facilities are used such as main pump unit, inlet and outlet passages, forebay and outlet sump, auxiliary equipments, power transmission and substation facilities, etc. Usually, the source water should be transported in a certain distance by the river or channel to the destination. Hydraulic loss and water loss of the river are integrated into power losses of the water. Further more, the operation performance of the pumping station is influenced. In this paper, hydraulic loss, evaporation loss and leakage loss were all considered. Based on variations of source water level, under certain water level of water transfer destination, the unknown water level, flow rate and river parameters could be obtained by the given parameter data based on energy conservation equation in fluid mechanics. Then, the relationships were determined respectively between demanding discharge of destination and pumping head, and between demanding discharge of destination and pumping discharge. The results showed that the relationships were nearly linear. Applying the linear relationships to the later optimization process in the algorithm, the repeated water level iteration was avoided. Also, the calculating amount and calculating time were reduced greatly. Taking three typical tidal level differences of maximum, mean, and minimum at Sanjisngying Intake of Yangtze River as a case, under certain water level and demanding discharge of Huai'an pumping station downstream, the model was built based on the system concluding main pump units, auxiliary equipments, power transmission and substation facilities, and water transferring facilities. The optimizing goal was the least daily operation cost, and the constraints included source water level, water level and flow rate of destination and each cross section of the river, single machine flow rate, the number of running pumps, and the balance of hydraulic loss and water loss. Also, the model was solved by Simulated Annealing-Particle Swarm Optimization Algorithm (SA-PSO), which had better global and local searching ability. Pump blade angles and the number of running pumps were defined as variables, and the objective function was chosen as the fitness function in the algorithm. The pump assembly performance at some blade angles could be got by fitting or interpolation. The results indicated that when the daily varied range of Sangjiangying water level was small, the operation cost was low because of high Sangjiangying water level and low head of Jiangdu pumping stations. When the daily varied range of Sangjiangying water level was large, it turned out the opposite. The cost could be saved by 0.62%~2.26%, 0.33%~3.26% and 0.22%~0.83%, respectively by adjusting pump blade angles than that of design blade angles. If the water-conveyance performance was considered, the optimal operation schemes were more reasonable. The methods could be applied in optimal operation for other pumping station system. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:20
Main heading:Rivers
Controlled terms:Algorithms - Auxiliary equipment - Costs - Energy dissipation - Fluid mechanics - Hydraulic machinery - Iterative methods - Losses - Operating costs - Optimization - Particle swarm optimization (PSO) - Power transmission - Pumping plants - Pumps - Simulated annealing - Turbomachine blades - Water - Water distribution systems - Water levels - Water resources
Uncontrolled terms:Energy conservation equations - Energy dissipation devices - Large pumping stations - Operation - Operation performance - Pumping station operation - Simulated annealing particle swarm optimization algorithms - Water transfers
Classification code:444 Water Resources - 446 Waterworks - 446.1 Water Supply Systems - 525.4 Energy Losses (industrial and residential) - 537.1 Heat Treatment Processes - 602.2 Mechanical Transmissions - 618.2 Pumps - 632.2 Hydraulic Equipment and Machinery - 901 Engineering Profession - 911 Cost and Value Engineering; Industrial Economics - 911.2 Industrial Economics - 921.5 Optimization Techniques - 921.6 Numerical Methods - 931.1 Mechanics
DOI:10.11975/j.issn.1002-6819.2015.17.005
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 7>
Accession number:20154301434119
Title:Calculation method of thermal response radius for vertical borehole heat exchangers
Authors:Li, Xiaoxing (1, 2); Hu, Xiamin (2); Zhang, Zhengwei (1, 2)
Author affiliation:(1) The College of Landscape Architecture, Zhejiang Agriculture and Forestry University, Hangzhou, China; (2) The College of Civil Engineering, Nanjing University of Technology, Nanjing, China
Corresponding author:Zhang, Zhengwei
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:248-253
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:At present, energy and environmental issues have become one of the most principal factors affecting the development of modern society. Energy conservation, exploitation of green renewable energy and environment protection has become urgent tasks in China. With the utilization of renewable energy sources and protection of environment, more and more researchers in the world pay attentions to the thermal environment of the geotechnical engineering. Some environment protection and energy saving technologies can cause the changes of soil temperature or even chemical contaminants diffusion, such as the development and utilization of shallow geothermal energy, nuclear waste disposal, landfill construction, thermal storage. Changes in the mechanical properties of the soil that caused by soil temperature field may lead to soil deformation, falling of ground stability and bearing capacity. Therefore, the research on heat transfer characteristics of rock and soil media has important theoretical values and practical significance in the development of geothermal resources, nuclear waste disposal, energy storage, landfill, heating pipe design and other aspects. The ground-source heat pump (GCHP) technology, as a clean and efficient renewable energy, has developed rapidly in recent decade. The distribution characteristics of the excess temperature in the soil medium were studied with the infinite line source heat transfer model in this paper. The results showed that the temperatures response at the surface of the borehole wall was the biggest in the soil medium around the ground, and heat exchanger which decayed exponentially with distance from the wall of the borehole, increased with operating time of the system. The heat transfer area also increased along with the thermal diffusion of medium and running time of the system. For the group of ground heat exchangers in the engineering, the temperature on the borehole wall of the group buried pipe was calculated according to the superposition principle, it was defined that the thermal response radius of the ground heat exchangers was the vertical distance between the adjacent borehole center when the excess temperature impact factor caused by other boreholes was less than or equal to 5%. With numerical analysis, the calculation method of the thermal response radius of the vertical ground heat exchangers was proposed. The calculating results showed that this method had better precision. The thermal response radius of the vertical ground heat exchanger increased along with the growth of the thermal diffusivity of the ground, duration of working time, borehole row numbers and borehole diameter, and was influenced significantly by the layout of the ground heat exchangers, and less by the borehole diameter under the same layout of the ground heat exchangers. In the case of common borehole diameter in the engineering, such as 115 and 135 mm, the graph of thermal response radius along with running time could be presented with different soil media of a single row, double rows and more than three rows drilling layout in this paper. The engineering examples showed that the method was simple and convenient for engineering design. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Heat exchangers
Controlled terms:Bearings (machine parts) - Boreholes - Calculations - Energy conservation - Environmental protection - Geotechnical engineering - Geothermal energy - Geothermal fields - Geothermal heat pumps - Heat pump systems - Heat storage - Heat transfer - Land fill - Numerical methods - Radioactive waste disposal - Radioactive wastes - Renewable energy resources - Soils - Temperature - Waste disposal
Uncontrolled terms:Development and utilizations - Distribution characteristics - Heat transfer characteristics - Shallow geothermal energies - Theoretical modeling - Thermal response - Vertical borehole - Vertical ground heat exchangers
Classification code:409 Civil Engineering, General - 452 Municipal and Industrial Wastes; Waste Treatment and Disposal - 452.4 Industrial Wastes Treatment and Disposal - 454.2 Environmental Impact and Protection - 481 Geology and Geophysics - 481.3.1 Geothermal Phenomena - 483.1 Soils and Soil Mechanics - 525.1 Energy Resources and Renewable Energy Issues - 525.2 Energy Conservation - 601.2 Machine Components - 616.1 Heat Exchange Equipment and Components - 622.5 Radioactive Wastes - 641.1 Thermodynamics - 641.2 Heat Transfer - 921 Mathematics - 921.6 Numerical Methods
DOI:10.11975/j.issn.1002-6819.2015.17.033
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 8>
Accession number:20154301434117
Title:Application effect of surplus air heat pump heating system in Chinese solar greenhouse
Authors:Sun, Weituo (1, 2); Guo, Wenzhong (1, 2); Xu, Fan (1, 2); Wang, Lichun (1, 2); Xue, Xuzhang (1, 2); Li, Yinkun (1, 2); Chen, Yongping (3)
Author affiliation:(1) Beijing Research Center of Intelligent Equipment for Agriculture, Beijing Academy of Agriculture and Forestry Sciences, Beijing, China; (2) Key Laboratory of Agri-Informatics, Ministry of Agriculture, Beijing, China; (3) Beijing Chongke High Technology Development Co., Ltd, Beijing, China
Corresponding author:Guo, Wenzhong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:235-243
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The Chinese solar greenhouse is a low carbon and energy-saving greenhouse structure, but it has an issue of energy imbalance between daytime and nighttime. Due to the surplus air heat energy, the solar greenhouse has to be ventilated in the daytime which leads to a large heat loss. However, cold damages and plant diseases and insect infection caused by low temperature and high humidity occur during cold winter night. In order to achieve transferring heat energy in terms of time and space inside the solar greenhouse, and then improve the utilization efficiency of surplus air heat energy, finally avoid low temperature in the greenhouses, a solar greenhouse surplus air heat pump heating system (SAHPHS) for the solar greenhouse was designed. In the daytime, air heat energy inside the solar greenhouse was pumped by the SAHPHS and stored in the heat reservoir. When indoor air temperature fell below the optimum range for crops in the nighttime, centrifugal fan and circulating water pump were started and heat energy stored in the heat reservoir was released directly via surface air cooler of the SAHPHS. As water temperature of the heat reservoir decreased to a certain value, the SAHPHS with a reverse operation was used to continue releasing heat energy forcibly. In addition, centrifugal fan and fin type electrical heater were used for emergency heating when encountering overcast weather for several days or extremely low air temperature. Tests for the SAHPHS were carried out from 10 Dec. 2014 to 10 Feb. 2015 and the effectiveness of the system was studied. The results showed that during running period of the SAHPHS, average air temperature inside the greenhouse was 2.8 to 4.4 higher than that in a comparable greenhouse in the nighttime, and the relative humidity decreased by 8% to 11.5%. Meanwhile, compared to the similar greenhouse without such system, average air temperature inside the greenhouse decreased by 3.7 to 5.2 and the relative humidity decreased by 12.3% to 16.5% during the daytime. So the SAHPHS not only had remarkable effects for heating and dehumidification in the nighttime, but also for cooling and dehumidification in the daytime. Air temperature in east-west direction inside the experimental greenhouse was found to be evenly distributed during heat collecting period in the daytime and heat releasing period in the nighttime with heat pump cycles, but have significant differences during heat releasing period with the usage of surface air cooler in the nighttime. Meanwhile the SAHPHS was found to have significant effect on raising daily average soil temperature in a depth of more than 20 centimeters. Heat collecting power of the SAHPHS was 12.5 to 16.4 kW, and coefficient of performance ranged from 3.3 to 4.2 during heat collecting period in the daytime. Heat releasing power of the SAHPHS was 9.3 to 10.3 kW, and coefficient of performance ranged from 6.6 to 7.4 during heat releasing period with the usage of surface air cooler in the nighttime. Coefficient of performance of the SAHPHS ranged from 3.8 to 4.1 with the SAHPHS running in a reverse heat pump cycle during heat releasing period in the nighttime. The SAHPHS was always under heating conditions in both heat collecting and heat releasing period. The coefficient of performance of the overall system in heating cycles reached 2.7, showing energy-saving effect. The SAHPHS had good application effects in heating, dehumidification and energy conservation, and this study would provide a new idea for the Chinese solar greenhouse energy-saving heating in the nighttime. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Greenhouses
Controlled terms:Air - Atmospheric temperature - Carbon - Cooling systems - Energy conservation - Fans - Greenhouse effect - Heat pump systems - Heating - Heating equipment - Humidity control - Pumps - Reservoirs (water) - Solar heating - Temperature - Thermal cycling
Uncontrolled terms:Average air temperature - Chinese solar greenhouse - Coefficient of Performance - Energy-saving effect - Indoor air temperature - Solar greenhouse - Surplus heat - Utilization efficiency
Classification code:441.2 Reservoirs - 443.1 Atmospheric Properties - 525.2 Energy Conservation - 616.1 Heat Exchange Equipment and Components - 618.2 Pumps - 618.3 Blowers and Fans - 641.1 Thermodynamics - 657.1 Solar Energy and Phenomena - 804 Chemical Products Generally - 821.6 Farm Buildings and Other Structures
DOI:10.11975/j.issn.1002-6819.2015.17.031
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 9>
Accession number:20154301434102
Title:Design and experiment of protective blanket for soil salination control
Authors:Mao, Haitao (1, 2); Huang, Qinghao (1); Long, Shunjiang (1); Wang, Zhengcheng (3)
Author affiliation:(1) Civil Engineering Institute of Chongqing Three Gorges College, Chongqing, China; (2) Institute of Water Conservancy and Hydroelectric Power, Wuhan University, Wuhan, China; (3) College of Water and Architecture of Shihezi University, Shihezi, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:121-127
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Soil salinization is a great challenge for Chinese agriculture, severely crippling the development of agricultural production. Soil salinization is often caused because strong evaporation and capillary transport salt ions to soil surface. Probably, the salt removal from soil surface by materials with strong capillary is a way to control salinization. In this study, we investigated the cause of saline-alkali formation of 5 types of soils in droughty areas, and proposed a protection blanket for soil salinization control based on the principle of soil capillary and tested its feasibility of control soil saline in 5 soils. The blanket was composed of sponge (stronger absorbent layer) and endothermic polyethylene weaved cloth (sforzato evaporation layer). The soil salt ions were absorbed by sponge into the outer cloth so that the salt could not accumulate on the surface of the soil. The blanket was used in 5 soils with different textures (gravel, silt/silt sand, silt/fine sand, silt, mild clay). The soils were collected from Fangcao Lake farmland, Hutubi county, Xinjiang (43°16'-45°20'N, 86°05'-87°07'26″E), and air-dried to mix with salt solution made of 36 g/L NaCl, 34 g/L KCl, and deionized water. The soils were filled into a box with area of 1 m<sup>2</sup>(30 cm depth to simulate tillage layer). The initial soil moisture was 12% and soil compactness was 0.8. The salt content of soils at 5 cm was determined destructively at 4, 12 and 20 d. The salt accumulation on soil surface was photographed. Meanwhile, another soil samples with salt water were placed in columns in 40-cm length and 20-cm diameter and 30-cm depth with blanket covered for measurements of salt-absorption dynamics and depth of the blanket. The results showed that: 1) The salt distribution on soil surface varied with soil texture and the salt crystals were much more in the coarse-grained soil (gravel sand and sand) with about 3-4 mm depth in 3-4 days than the fine granular soil (clay and silt) with salt accumulation at a comparatively low rate so that crystal salt could not observed in 10-12 days; 2) The salt accumulation was obvious in early stage of experiment in the coarse soil particles but in the later stage of experiment in the fine soil particles; 3) The blanket could reduce salt content in 0-10 cm soil layer by more than 80% (P<0.05), and reduce in 10-20 cm by more than 50% (P<0.05) after 4 days under the condition with the outdoor temperature of 25 and dry ventilation allowed; Using the blanket, the salt content in 20-30 cm depth could be reduced by more than 50%, and more than 20%-30% (P<0.05) for sandy soils, clay and loam soil, respectively. For practical application, the salt content reduction of 30% can greatly improve soil fertility and cultivability, and effectively alleviate the impact of salinity on the growth of crops. The results above indicate that the protective blanket is an effective measure for saline-alkali land amelioration. Theoretically, its effect should be best when soil capillary is strongest. However, its feasibility still need to be validated in more studies and in fields. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:11
Main heading:Soils
Controlled terms:Agriculture - Capillarity - Deionized water - Evaporation - Gravel - Particles (particulate matter) - Salt removal - Sand - Silt - Soil moisture - Soil surveys - Water absorption
Uncontrolled terms:Absorption dynamics - Agricultural productions - Capillary transport - Coarse-grained soils - Initial soil moisture - Protective blanket - Saline-alkali land amelioration - Sponge
Classification code:445.1 Water Treatment Techniques - 483.1 Soils and Soil Mechanics - 631.1 Fluid Flow, General - 802.3 Chemical Operations - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2015.17.016
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 10>
Accession number:20154301434111
Title:Flood monitoring in Hainan Island based on HJ-CCD data
Authors:Li, Hailiang (1); Wang, Xiuhua (2); Dai, Shengpei (1); Tian, Guanghui (3)
Author affiliation:(1) Institute of Scientific and Technical Information, Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Practical Research on Tropical Crops Information Technology In Hainan, Danzhou, China; (2) Science and Technology Department, Chinese Academy of Tropical Agricultural Sciences, Haikou, China; (3) Hainan Institute of Meteorological Sciences, Haikou, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:191-198
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Flood monitoring is one of the main tasks of agricultural monitoring. For surface observation, it consumes many manpower, resources as well as delayed information, all of those can be overcome by use of remote sensing monitoring flood disaster. The spatial and temporal resolution of HJ-1A/1B-CCD data is 30 m and 2 d. HJ-1A/1B-CCD data are desired remote sensing data of flood monitoring. We chose Hainan Island as research area and selected 400 training samples. Of them, 100 samples were from surface waters and wetlands, respectively, and 50 samples were respectively for forest lands, cultivated lands, roads and settlement places. In this paper, we analyzed and compared three water indexes: normalized difference water index (NDWI), normalized difference water index based on blue light (NDWI-B) and combined index of NDVI and NIR for water body identification (CIWI) by using the division degree (DD). Result showed that when NDWI-B was used to extract pure water, the division degrees of pure water to forest land, cultivated land, road and habitation were all between NDWI and CIWI. The division degrees of NDWI-B in these aspects were obviously higher than NDWI and CIWI when extracting wetland, which meant that when applying HJ-1A/1B CCD data to extract lack branch, small water bodies and wetland, the NDWI-B was better than NDWI and CIWI. The comprehensive discriminations of NDWI-B model were 31.30% and 28.13%, respectively. Thus, NDWI-B model was the optimal model when carrying out flood monitoring in Hainan Island. Based on the error matrix theory in combination with the actual measurement of sample data, the precision of water (pure water and wetland) in Hainan Island extracted by the NDWI-B was verified. Result showed that the user accuracy of water and non-water were 90.29% and 92.78%, respectively, and the overall accuracy was 91.50%. Through repeated comparison between the water index value and the surface feature type in the sampling point, when using NDWI-B model to extract water, the water scope of threshold value -0.015 was the largest, the broken figure spot was relatively less, and it was easy to exclude road and habitation. As such, the water identification's threshold value of NDWI-B was ensured, which was -0.015. Remote sensing images with better data qualities during the monitoring period (Sep. 26th, Oct. 6th, Oct. 12th, Oct. 20th, 2010, time series data) were chosen and the flood disaster conditions in Hainan Island from Sep. 25th, 2010 to Oct. 25th, 2010 were monitored by the NDWI-B. Result showed that the disastrous situation on Oct. 12th was the severest. The inundated area of the whole island reached 120.22 km<sup>2</sup>, the ceiling value during the monitoring period. Newly-emerged water bodies, mainly spreading over villages, farmlands and roads, were in all cities and counties except Dongfang, Changjiang and Ledong. Regionally, Wenchang, Qionghai, Haikou and Ding'an in the east were severely flood affected areas; Dongfang, Changjiang and Ledong in the west were less affected. The most affected land-use type by the flood in Hainan Island was the paddy field, whose inundated areas were 54.31 km<sup>2</sup>, 61.46 km<sup>2</sup>, and 42.58 km<sup>2</sup>on Oct. 6th, Oct. 12th and Oct. 20th, respectively. The secondly affected land-use type was the dry land. Its inundated areas were 22.56 km<sup>2</sup>, 29.59 km<sup>2</sup>and 18.36 km<sup>2</sup>on Oct. 6th, Oct. 12th and Oct. 20th, respectively; the inundated areas accounted for 73.13%, 75.73% and 71.37%, respectively in the whole inundated area. Besides, taking Sanjiang farm in Meilan District, Haikou City as an example, we calculated the drowned water depth in the farm at October 6th, 2010. The result showed the drowned water depth of some fishpond and cultivated lands in Sanjiang farm was more than three meters. The flooding and water logging disaster situation was quite serious. Study showed that when recognizing the pure water the distinction degree of NDWI-B was a little lower than that of the CIWI, but high when recognizing the wetland. Besides advantages of larger land and water distinction degree and higher extracting precision of water area, the NDWI-B can also identify the water and wetland in small area. It was a relatively ideal model in monitoring flood disasters in Hainan Island. This paper provided references for the water resource management, the dynamic monitoring of flood disaster and disasters prevention as well as damages reduction in Hainan Island. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Extraction
Controlled terms:Accidents - Disaster prevention - Disasters - Floods - Forestry - Image reconstruction - Land use - Landforms - Monitoring - Remote sensing - Roads and streets - Satellites - Surface waters - Transportation - Water management - Water resources - Wetlands
Uncontrolled terms:Agricultural monitoring - Blue light - Hainan island - HJ satellites - Normalized difference water index - Remote sensing monitoring - Spatial and temporal resolutions - Waterresource management
Classification code:403 Urban and Regional Planning and Development - 406.2 Roads and Streets - 444 Water Resources - 444.1 Surface Water - 481.1 Geology - 655.2 Satellites - 802.3 Chemical Operations - 914.1 Accidents and Accident Prevention
DOI:10.11975/j.issn.1002-6819.2015.17.025
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 11>
Accession number:20154301434100
Title:Improvement of interpolation methods for surface micro-topography spatial distribution in border irrigation simulation
Authors:Liu, Shanshan (1); Bai, Meijian (1); Xu, Di (1); Zhang, Shaohui (1)
Author affiliation:(1) National Center of Efficient Irrigation Engineering and Technology Research, Beijing, China
Corresponding author:Bai, Meijian
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:108-114
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Surface micro-topography is one of the most important factors affecting irrigation process and performances. In view of the interpolation problem of surface micro-topography in irrigation model, using observed data on surface relative elevation of 4 different size ridge field, this study firstly compared the interpolation accuracy and program running time of Kriging interpolation, cubic spline interpolation and inverse distance weighted interpolation (IDW), and then analyzed the trend of Kriging interpolation program running time with the change of interpolation grid numbers under different sizes of ridged field. Furthermore, the combination interpolation methods of Kriging interpolation and cubic spline interpolation, and Kriging interpolation and inverse distance weighted interpolation were proposed, and the surface flow advance processes simulated based on data on surface relative elevation interpolated by the combination method and kriging interpolation were compared with observed surface flow advance process. The results showed that compared to the cubic spline interpolation and IDW, the interpolation accuracy of Kriging interpolation was the highest and Kriging interpolation could truthfully reflect the spatial distribution of micro-topography but the program running time was the longest, which had a great impact on the computational efficiency of irrigation model, while the program running time of cubic spline interpolation and IDW was relatively short, but their accuracies were low, which affected greatly the simulation accuracy of irrigation model. The running time of Kriging interpolating program increased with the size of ridge field and the number of interpolation grid. The reason of that might be there was an increase trend of equations and equations number in Kriging interpolation with the increase of ridge field size and interpolation gird numbers. The program running time of the combination interpolation method of Kriging interpolation and cubic spline interpolation and that of combination interpolation method Kriging interpolation and inverse distance weighted interpolation was the same, but the interpolation accuracy of the former was higher. In order to both meet the requirements of interpolation accuracy and computational efficiency of irrigation model, it was feasible to use the combination method of Kriging interpolation and cubic spline interpolation for surface elevation interpolation in irrigation model. For those ridge fields with their area less than 2700 m<sup>2</sup>, the combination interpolation could satisfy the requirements of mean absolute error less than 0.5 mm and program running time less than 10 s. For those ridge fields with their area more than 2700 m<sup>2</sup>, the combination interpolation could satisfy the requirements of mean absolute error less than 0.5 mm and program running time less than 20 s when the intermediate interpolation grid number was 1/4 of irrigation model grid number and meet the requirements of mean absolute error less than 1 mm and program running time less than 10 s when the intermediate interpolation grid number was 1/8 of irrigation model grid number. The surface flow advance processes simulated based on the surface elevation data interpolated by the combination method with the 1/4 and 1/8 irrigation model grid numbers and Kriging interpolation were similar with the observed data. Therefore, the intermediate interpolation grid number could be selected between 1/4 and 1/8 of irrigation model grid number depending on the requirements of interpolation accuracy and running time. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:23
Main heading:Interpolation
Controlled terms:Computational efficiency - Efficiency - Errors - Inverse problems - Irrigation - Models - Spatial distribution - Surface topography - Topography
Uncontrolled terms:Cubic spline - Cubic-spline interpolation - Interpolation problems - Inverse distance-weighted interpolation - Kriging - Kriging interpolation - Surface elevation data - Surface elevations
Classification code:821.3 Agricultural Methods - 913.1 Production Engineering - 921 Mathematics - 921.6 Numerical Methods - 931.2 Physical Properties of Gases, Liquids and Solids - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2015.17.014
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 12>
Accession number:20154301434095
Title:Acoustic analysis and structural optimization of dual-chamber reactive muffler
Authors:Xiang, Longyang (1); Zuo, Shuguang (1); Wu, Xudong (1); Zhang, Jun (1); Liu, Jingfang (1)
Author affiliation:(1) Clean Energy Automotive Engineering Center, Tongji University, Shanghai, China
Corresponding author:Zuo, Shuguang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:65-71
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The existing studies of the acoustic performance of reactive mufflers are mainly based on the numerical method or the transfer matrix method. But the numerical methods like the finite element method or the boundary element method mean plenty of time needed, and the transfer matrix method is only useful below the cutoff frequency of the expansion chamber. This paper use two-dimensional analytical method to study the acoustic behaviors of dual-chamber reactive muffler. This method is based on the sound wave equations in the muffler. Firstly the sound pressure and particle velocity in the air domains of the dual-chamber reactive muffler are expressed according to the Helmholtz equation, in which there are some unknown variables to be solved. Secondly the expressions are used to construct an equation set according to the boundary conditions at the interfaces of different domains of the muffler. The conditions are that the sound pressure and particle velocity are continuous at the interfaces. That means the sound pressures expressed in adjacent domains are equal at the interface, which is the same way for the particle velocity. At last the amplitudes of the sound pressure of all domains are solved according to the equation set. Then the transmission loss can be calculated based on the sound pressure amplitudes of the inlet and outlet of the muffler. A dual-chamber reactive muffler is manufactured for the experiment. The transmission loss of the muffler was measured by the two-load method. The impedance tube is used for the experiment. The result shows that the calculated transmission loss agrees well with the measured one below 3000 Hz. On the contrary, the transfer matrix method is accurate only below 1299 Hz for this muffler. This means the two-dimensional analytical model is effective for the analysis and design of dual-chamber reactive muffler. Then the effects of several parameters on the transmission loss of the dual-chamber reactive muffler are analyzed. The analysis shows that the dual-chamber reactive muffler performs better than the one-chamber reactive muffler with the same outer dimensions. The muffler with two chambers attenuates much more noise on a wider frequency band than that with only one chamber. It also shows that the clapboard hole radius and its position in the baffle have an obvious influence on the acoustic behavior of the dual-chamber reactive muffler. As the radius of the clapboard hole increases, the acoustic behavior becomes worse. Then the paper uses the genetic algorithm for the optimal design of the dual-chamber reactive muffler. The variables of the optimization include the clapboard radius, the radii of inlet/outlet and expansion chambers and the lengths of the expansion chambers. The denoising objective is the noise between 1000 and 3000 Hz. The constraint condition is that the outer dimension of the muffler could not become larger. The optimization leads to a wonderful result. After optimization, the average value of transmission loss between 1000 and 3000 Hz increases from 17.2 to 39.5 dB, with a growth of 130%. The study in this paper demonstrates that the proposed theoretical model of dual-chamber reactive muffler can be used for the analysis and design of the muffler effectively and efficiently, which is really helpful in the industrial application. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Transfer matrix method
Controlled terms:Acoustic impedance - Acoustic noise - Acoustic properties - Acoustics - Air - Boundary element method - Cerenkov counters - Cutoff frequency - Finite element method - Frequency bands - Genetic algorithms - Mufflers - Numerical methods - Optimization - Sailing vessels - Structural optimization - Velocity control - Wave equations - Wave transmission
Uncontrolled terms:Acoustic analysis - Acoustic performance - Analytical method - Constraint conditions - Particle velocities - Theoretical analysis - Theoretical modeling - Transmission loss
Classification code:612.1.1 Internal Combustion Engine Components - 674.1 Small Marine Craft - 731.3 Specific Variables Control - 751 Acoustics, Noise. Sound - 804 Chemical Products Generally - 921 Mathematics - 944.7 Radiation Measuring Instruments
DOI:10.11975/j.issn.1002-6819.2015.17.009
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 13>
Accession number:20154301434118
Title:Design and test of LED surface light source used in plant factory with water-cooling system
Authors:Liu, Xiaoying (1); Jiao, Xuelei (1); Yao, Xuyang (1); Xu, Zhigang (1)
Author affiliation:(1) Agricultural College of Nanjing Agricultural University, Nanjing, China
Corresponding author:Xu, Zhigang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:244-247
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The luminous efficiency and energy consumption of LED (light emitting diode) are affected by heat dissipation of high power LED. In the study, LED surface light source used in plant factory with water-cooled cooling system was designed, and the purpose was to take away the heat generated by the LED using water cycle, to reduce the junction temperature and delay light attenuation of the LED, to distribute the heat according to requirement for heat of plant factory, and thus to reduce energy consumption for controlling temperature. The system was mainly made of LED surface light source, radiator and water circulation system. LED surface light source was made of the high-power LED, with 28 identical array units which were arrayed in 4 rows and 7 columns, and each array unit consisted of 44 LEDs. LED surface light source could give out red, blue, white, green and yellow light or any combination light made by above-mentioned light. Supplying voltage of light source was 220 V, and power of LED was provided by the conversion from 220V AC (alternating current) signal to 0-48V DC (direct current) signal. Electrical energy of the light with different colors was respectively supplied by independent power. Dimmer was used to adjust output DC voltage of the power, to regulate current of the LED and realize the aim of adjusting light intensity. Light intensity of LED surface light source could be adjusted in the range of 0-2000 μmol/(m<sup>2</sup>·s). The radiator of LED surface light source (length×width×height, 500 mm×400 mm×20 mm) was made of hot galvanized Q235 steel, which was composed of bottom plate, hanging lug, cover plate, etc. Water path of bottom plate was S type. The function of water circulation system was to transfer the heat produced by LED surface light source to water. After giving out heat, water was recycled into the radiator to maintain the temperature of the radiator at a low level. The water circulation system mainly consisted of supplying water tank, constant-flow pump, recycling water tank, valves, radiators, sensors and pipelines, etc. The waterway was divided into 2 parts; in the heating season, the heat was input into plant factory for raising indoor temperature, while in the non heating season, the heat was output to the outdoor, and then water was cooled by air before entering the water circulation system. During the time from 2 to 6 a.m. of November 2, 3 and 4, 2014, the effect of the cooling system of LED surface light source was tested in 13 m<sup>2</sup>plant factory in the Life Science Building of Nanjing Agricultural University. Under water cooled and non-water cooled conditions, radiator temperatures of 4 corners on the radiator were measured, and average value for each measurement was recorded. The results showed that water-cooled system had obvious effect of reducing temperature of LED surface light source. Compared with non-water cooled system, plate temperature was lower, which was decreased by at least 5.3 and up to 19.3. Water-cooled system directly reduces the temperature of the radiator, and indirectly reduces the junction temperature of the LED. And thus it can prolong the service life of LED surface light source. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:13
Main heading:Light emitting diodes
Controlled terms:Cooling - Cooling systems - Cooling water - Energy utilization - Light sources - Radiators - Recycling - Tanks (containers) - Thermoelectric equipment - Water cooling systems - Water recycling - Water tanks
Uncontrolled terms:Junction temperatures - Plant factory - Radiator temperature - Reduce energy consumption - Reducing temperature - Water circulation system - Water cooled cooling systems - Water-cooled system
Classification code:452.3 Industrial Wastes - 525.3 Energy Utilization - 615.4 Thermoelectric Energy - 616.1 Heat Exchange Equipment and Components - 619.2 Tanks - 641.2 Heat Transfer - 714.2 Semiconductor Devices and Integrated Circuits
DOI:10.11975/j.issn.1002-6819.2015.17.032
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 14>
Accession number:20154301434124
Title:Effect of thawing methods on processing quality of Antarctic krill
Authors:Cao, Rong (1); Chen, Yan (1); Zhao, Yuran (2); Liu, Qi (1); Huang, Xianbin (1)
Author affiliation:(1) Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, China; (2) Shandong Entry-Exit Inspection and Quarantine Bureau, Qingdao, China
Corresponding author:Liu, Qi
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:289-294
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Antarctic krill (Euphausia superba) is widely distributed in Antarctic waters. The resource of Antarctic krill is rich, whose fishable amount is up to 100 million tons each year. In China, considerable amount of Antarctic krill is frozen and stored in boats before transported to the land for processing. Therefore, thawing is indispensable in Antarctic krill industry. The thawing way has great effect on the quality of fishery materials. In order to explore how thawing process influenced the quality of Antarctic krill as raw material, 3 ways including natural air thawing, static water thawing and low-temperature air thawing were designed in this study. The consumption of time, sensory evaluation and biochemical indices such as non-protein nitrogen (NPN), total volatile basic nitrogen (TVB-N) and thiobarbituric acid reactive substance (TBARS) were determined for each kind of thawing method. The results showed that the thawing time taken by natural air way, static water way and low-temperature air way was 220, 51 and 826 min respectively. The sensory score of Antarctic krill with static water thawing was the highest, followed by natural air way and low-temperature air way. The NPN values of Antarctic krill thawed by the 3 ways were 6.89, 8.55 and 12.13 mg/g respectively for static water thawing, natural air thawing and low-temperature air thawing, with the highest value of low-temperature air way, followed by natural air way and static water way in sequence. The TVB-N values of Antarctic krill thawed by the 3 ways were 9.60, 10.33 and 22.47 mg/100 g, respectively. The TVB-N value of low-temperature air way was significantly higher than the other 2 ways, but those of the static water way and natural air way had no significant difference (P>0.05). The TBARS values of Antarctic krill thawed by the 3 ways were 6.77, 4.78 and 2.17 mg/kg, respectively. The differences were significant (P<0.01), with the highest value of static water way, followed by natural air way and low-temperature air way. The proportion of polyunsaturated fatty acids of total fat from Antarctic krill was more than 30%. Low-temperature air thawing had a certain effect on the protection of polyunsaturated fatty acids. In conclusion, in the process of production, choosing the way to thaw Antarctic krill material should fully consider the type of products. The way of static water thawing is suitable for general food processing. The ways of static water thawing and natural air thawing are suitable for fishmeal production. The way of low-temperature air thawing is suitable for shrimp oil extraction. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:18
Main heading:Thawing
Controlled terms:Agricultural products - Blood - Fatty acids - Food processing - Nitrogen - Oils and fats - Polyunsaturated fatty acids - Proteins - Quality control - Temperature - Water quality
Uncontrolled terms:Antarctic krill - Biochemical indices - Euphausia superba - Fatty acid profiles - Low temperatures - Processing quality - Thiobarbituric acid reactive substances - Total volatile basic nitrogens
Classification code:445.2 Water Analysis - 461.2 Biological Materials and Tissue Engineering - 641.1 Thermodynamics - 804 Chemical Products Generally - 804.1 Organic Compounds - 821.4 Agricultural Products - 822.2 Food Processing Operations - 913.3 Quality Assurance and Control
DOI:10.11975/j.issn.1002-6819.2015.17.038
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 15>
Accession number:20154301434103
Title:Effects of saline improvement and leaching of desulphurized gypsum combined with furfural residue in newly reclaimed farmland crack alkaline soil
Authors:Yang, Jun (1, 2); Sun, Zhaojun (3); Liu, Jili (3); Ma, Fei (3)
Author affiliation:(1) College of Civil and Hydraulic Engineering, Ningxia University, Yinchuan, China; (2) Yinchuan College of Energy Resources, Yinchuan, China; (3) Development Center of Application Research on New Technology, Ningxia University, Yinchuan, China
Corresponding author:Sun, Zhaojun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:128-135
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Takyric solonetz land, a typical subclass of alkali soil, is widely distributed in the North of Yinchuan Plain of Ningxia province, West Hetao Plain and north Xinjiang desert steppe in China. Due to the hard texture and poor permeability, it has become the main factor severely affecting the development of local agriculture, and is expected to bring threat to the regional food security in the future. More and more improvement techniques have been developed to achieve a sustainable utilization of saline-alkali waste land, but the effect of leaching, gypsum, furfural residue and their interaction on soil properties and yield of oil sunflower in newly reclaimed crack alkaline land remains unknown. In order to investigate the effect of leaching, gypsum and furfural residue on soil properties and yield of oil sunflower planted in newly reclaimed takyric solonetz land, a comparative field experiment in 2012 was conducted at the farmland of Ningxia Xi Da Tan of China (106°24'209"E, 38°50'289"N). Three leaching amount (3600, 4500 and 4800 m<sup>3</sup>/hm<sup>2</sup>) and four application rate of furfural residue (0, 15, 22.5 and 30 t/hm<sup>2</sup>) were designed. Besides, the desurlphurized gypsum (28 t<sup>3</sup>/hm<sup>2</sup>) was applied in combination with furfural residue. Then, measurements were made for soil physical and chemical properties, soil salt ions and yield of oil sunflower of different treatments. The test items were soil pH, total salinity, alkalinity, total alkalinity, salt ions, water holding capacity of soil, water permeability of soil and germination days, germination rate, survival rate, height, stem diameter, head diameter and yield of oil sunflower. The results showed that soil pH, total salinity, alkalinity, total alkalinity and salt ions were significantly reduced in the soil of layer 0-20 cm (P<0.05) under the leaching water volume of 4500 m<sup>3</sup>/hm<sup>2</sup>and furfural residue (22.5 t/hm<sup>2</sup>). The pH, alkalinity, total alkalinity and salinity of soils were decreased from 9.65, 38.4%, 0.51 cmol/kg and 5.38 g/kg before experiment to 7.6, 15.3%, 0.31 cmol/kg and 1.66 g/kg after experiment, respectively. They were decreased by 21.2%, 60.2%, 39.2% and 69.1%, respectively in the soil of layer 0-20 cm. These changes facilitated the germination and growth of oil sunflower, thereby increasing yield. Among all the treatments, the combination of leaching water volume of 4500 m<sup>3</sup>/hm<sup>2</sup>and furfural residue 22.5 t/hm<sup>2</sup>was best with the highest oil sunflower yield of 3195.8 kg/hm<sup>2</sup>. In addition, after application of furfural residue and desurlphurized gypsum, the Na<sup>+</sup>in 0-20 cm decreased greatly but increased in 40-60 cm. Similarily, Ca<sup>2+</sup>also was accumulated in 20-60 cm. Mg<sup>2+</sup>, K<sup>+</sup>, Cl<sup>-</sup>, SO<inf>4</inf><sup>2-</sup>were also increased in the soil layer of 0-60, 0-60, 60-80, and 40-60 cm, respectively. It was highly likely due to low water permeability of takyric solonetz land. In order to improve the effect of leaching over a field, the clay layer deep in soil profile should be loosened at lease to 80 cm, which could increase soil water infiltration rate and depth and discharge soil salt ions to avoid salt accumulation in deep soil and then returning to the soil surface by evaporation. The findings of this study will provide technical support for improving the newly reclaimed takyric solonetz farmlands and controlling water and salt, and provide data support for the development of irrigation systems. In sum, it suggests that gypsum (28 t<sup>3</sup>/hm<sup>2</sup>) combined with furfural residue (22.5 t/hm<sup>2</sup>) and leaching (4500 m<sup>3</sup>/hm<sup>2</sup>) and soil loosened to 80 cm is the better way to improve newly reclaimed farmland takyric solonetz soil. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Soil surveys
Controlled terms:Aldehydes - Alkalinity - Cracks - Cultivation - Farms - Food processing - Food supply - Furfural - Gypsum - Infiltration - Ions - Irrigation - Landforms - Leaching - Oils and fats - pH - Reclamation - Soil moisture - Soil testing - Soils - Sunflower oil
Uncontrolled terms:Alkaline soils - Different treatments - Improvement technique - Salt control - Salt ions - Soil physical and chemical properties - Sustainable utilization - Water holding capacity
Classification code:481.1 Geology - 482.2 Minerals - 483.1 Soils and Soil Mechanics - 801.1 Chemistry, General - 802.3 Chemical Operations - 804.1 Organic Compounds - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.3 Agricultural Methods - 822.2 Food Processing Operations - 822.3 Food Products
DOI:10.11975/j.issn.1002-6819.2015.17.017
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 16>
Accession number:20154301434122
Title:Calculation method of cultivated land consolidation ecological potential in China
Authors:Tang, Xiumei (1); Pan, Yuchun (1); Hao, Xingyao (1); Liu, Yu (1)
Author affiliation:(1) Beijing Research Center for Information Technology in Agriculture, Beijing Academy of Agriculture and Forestry Sciences, Beijing, China
Corresponding author:Pan, Yuchun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:270-277
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Cultivated land consolidation (CLC) is the key component of agricultural land consolidation and the potential of CLC has great significance for the planning of land consolidation and major projects. Based on the evaluation of quantitative and qualitative potential of CLC, in this study, we explored the ecological potential of CLC in China at county scale using the ecosystem services value (ESV) to characterize the ecological potential. First, the national basic average ESV of cultivated land was determined by the existing research. Then, the reference ESV of each county in China was calculated after the spatial correction and time scale correction. Combined with the original area of cultivated land, the total ESV of each county in China was calculated. Second, the qualitative potential of CLC was calculated by pre-evaluation of farmland classification, and then the ESV of cultivated land after CLC was obtained by combining the farmland classification, production capacity and ESV. The total ecological potential included the added ESV of original cultivated land after CLC and the ESV of added cultivated land. The added ESV of original cultivated land was equal to the product of the basic ESV after CLC and the area of original cultivated land. The ESV of added cultivated land was equal to the product of the basic ESV before CLC and the area of new cultivated land. Finally, the ecological potential of each county was calculated with the ESV before and after CLC. Based on the result on county-scale, we got the total ecological potential of CLC on provincial-scale and, national scale. The results proved that there were considerable and concentrated potential capacities of the CLC in China. The total ecological potential was 6.14×10<sup>11</sup>Yuan. The counties with high ecological potential were mainly distributed in Heilongjiang and Jinlin in Northeast China, Henan, Anhui and Hubei in the east, Sichuan in the southwest, Xinjiang in the northwest; and the counties with low ecological potential were distributed in the southwest, Fujian-Canton-Hainan and Qinghai-Tibet area. The provinces with high ecological potential were mainly distributed in the middle east region, and the highest number was Sichuan province with the ecological potential of 8.02×10<sup>10</sup>Yuan. This had a great relationship with the large area of cultivated land area and high basic average ESV of cultivated land in Sichuan province. In nine major land use areas in China, the region with highest ecological potential was the Hunan-Hubei-Anhui-Jiangxi region, reached to 1.59×10<sup>11</sup>Yuan. The ecological potential of the Southwest region and the Beijing-Tianjin-Hebei-Shandong region were more than 9.00×10<sup>10</sup>Yuan, and the Jiangsu-Zhejiang-Shanghai region, the Northeast region and the Shanxi-Henan region achieved to 5.00×10<sup>10</sup>Yuan. The regions with low ecological potential were the Southwest region and the Fujian-Canton-Hainan region, especially the Qinghai-Tibet region, only 1.16×10<sup>8</sup>Yuan. In this study, we explored the new ideas and methods of ecological potential of cultivated land. The result provided guidance for the planning and ecological construction of CLC, the ecological protection in key areas. The ecological potential of CLC was represented by added characterization of ESV in this study. Owing to the limitation of data availability, the calculation of ecological potential in this study neglected the ESV reduction caused by the adjustment of other land use types. The future study should focus on the calculation of overall value of ecological potential on the CLC project regions with the consideration of ecological environment, social effect, and human development. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Ecology
Controlled terms:Calculations - Consolidation - Ecosystems - Farms - Land use
Uncontrolled terms:Cultivated lands - Ecological construction - Ecological environments - Ecological protection - Ecosystem services value - Potential - Production capacity - Spatial corrections
Classification code:403 Urban and Regional Planning and Development - 454.3 Ecology and Ecosystems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921 Mathematics
DOI:10.11975/j.issn.1002-6819.2015.17.036
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 17>
Accession number:20154301434090
Title:Water distribution test system of sprinkler based on wireless transmission technology
Authors:Tang, Yue (1); Li, Chen (1)
Author affiliation:(1) Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:27-34
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In sprinkling irrigation, evaluation of spraying quality mainly depends on water distribution test systems. Commonly, there are at least dozens of test points needed in the water distribution test, and sometimes hundreds of them are used in some particular cases. The space between rain gauges ranges from 0.5 m to 2 m by the coverage diameter of sprinkler which commonly requires high mobility and convenient reading functions. Traditionally, the test requires measurements of hundreds of points by use of standard measuring cup. Following that, a great deal of data from the test cups are collected for the calculation of sprinkler irrigation uniformity, and then water distribution map were manually drawn. All of those bring problems like heavy workload or low precision of the measured results. The water distribution testing software implemented can be used to draw the map of water distribution or the calculation, but it may not realize the function of real-time plot with the separation of water collecting apparatus. Moreover, the data downloaded into computer from the measuring apparatus cannot be exported to Excel, which may cause errors. Moreover, the drawings of water distribution map can only be printed in a specified angle and the outline of the water distribution cannot be viewed in a time. In order to improve the sprinkler performance and optimize the water distribution, a new approach of using wireless to test water distribution of sprinkler was proposed based on ZigBee technology, a new short-distance wireless network standard for sensor network with the distinct advantages of low energy consumption, low latency, and long battery lives, and Matlab in the double tipping bucket rain gauge, in which a wireless module ZigBee, and a hall sensor were installed to receive and store signal generated by the tipping bucket rain acquisition parts by CC2530 module. The rain gauges were arranged in the test field in a rectangular and radial direction and each one was numbered uniquely in the entire network. The frequency of communication between receiver and upper computer was 2.4GHz. In order to avoid signal congestion, the number of routing nodes was enlarged and tree type networks were used in the rain gauges. Terminal nodes were responsible for collecting signal and delivering it to the routing nodes during working conditions and the routing nodes transmitted the signal to the coordinators. The ZigBee coordinator node received signal and delivered it to the upper computer in which a real-time analytic software was developed by graphical user interfaces (GUI) of Matlab. The software allowed us to analyze data precisely with intuitive three-dimension image. The new developed test system had distinct advantage like improved generality, easy expansibility, high reliability and interoperability compared to the traditional one. A water distribution test was conducted as to the S800 rotating sprinkler produced by the Toro Company. The error of this system and manual measurement was less than 0.1 mm/h. It can bear at least 2940 reversal per hour without leak. The software system calculated 11 combination sprinkler irrigation Christiansen uniformity coefficients with the combination spacing coefficient ranged from 1.0 to 2.0. The test results showed that the Christiansen uniformity coefficients of sprinkler reached 70.6%. The Christiansen uniformity coefficients corresponding to the combination spacing coefficient of rectangle ranged from 1.0 to 1.6 and that of triangle range from 1.0 to 1.2 or 1.5 to 1.7 were up to 75%, which met the expected requirements. The entire system provided reliable data collection method and functional data analysis software for researcher to develop new sprinklers. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:16
Main heading:Interoperability
Controlled terms:Computer software - Energy utilization - Gages - Graphical user interfaces - Hall effect transducers - Hose - Irrigation - Low power electronics - MATLAB - Nozzles - Quality control - Rain - Rain gages - Sensor nodes - Software testing - Sprinkler systems (irrigation) - Testing - User interfaces - Water - Water supply systems - Wireless sensor networks - Zigbee
Uncontrolled terms:Functional data analysis - Graphical user interfaces (GUI) - Low energy consumption - Reliable data collections - Sprinkling irrigation - Tipping bucket rain gauge - Water distributions - Wireless transmissions
Classification code:443.3 Precipitation - 446.1 Water Supply Systems - 525.3 Energy Utilization - 619.1 Pipe, Piping and Pipelines - 722 Computer Systems and Equipment - 723 Computer Software, Data Handling and Applications - 723.5 Computer Applications - 821.1 Agricultural Machinery and Equipment - 821.3 Agricultural Methods - 913.3 Quality Assurance and Control - 943.3 Special Purpose Instruments
DOI:10.11975/j.issn.1002-6819.2015.17.004
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 18>
Accession number:20154301434096
Title:Simulated experiment on drainage and fine sediment retention effects of geotextiles in land reclamation with Yellow River sediments
Authors:Wang, Peijun (1, 2); Shao, Fang (1); Liu, Junting (1); Li, Xingyu (1); Hu, Zhenqi (1); Yost, Russell S. (2)
Author affiliation:(1) Institute of Land Reclamation and Ecological Restoration, China University of Mining and Technology (Beijing), Beijing, China; (2) Department of Tropical Plant and Soil Sciences, University of Hawai'i at Mnoa, Honolulu; HI, United States
Corresponding author:Hu, Zhenqi
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:72-80
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Yellow River sediments have been used as filler for land reclamation in mining subsidence land nearby Yellow River. During the reclamation, water is often drained directly and rapidly from outlet excavated in the center of the cofferdam, leading to fine sediments (clay and most of silt) lost with drainage and deposited in ditch, poor lateral drainage of saturated sediments, low drainage efficiency by only vertical infiltration in reclamation strip. In this study, we tested the feasibility of geotextiles used in the Yellow River sediments to increase the lateral drainage velocity and reduce the sediment loss in drainage in a laboratory experiment. The Yellow River sediments were filed in glass tanks to simulate the land reclamation process. Two kinds of geotextiles including 250 (ZW-250) and 300 g (ZW-300) a piece were selected. In the treatments with geotextiles, the whole cross section was opened for drainage. A control without geotextile (CK) was designed with narrow outlet in the center of the cross section for drainage. Similarly, glass holder and wire netting were used for supporting in all the three treatments. Sediment content in the drainage, grain size distribution of sediments in the drainage, grain size distribution of surface sediments (0-2 cm) in the glass tank and water content of filled surface sediments (0-15 cm) and bottom sediments (15-30 cm) in the glass tank of the three treatments were measured by laser grain size analyzer and other conventional methods. The results showed that there was little difference on sediment content in drainage of the three treatments. In the first stage (10 min after drainage stabilization), the sediment content in drainage of ZT-250 and ZT-300 treatments was higher than that of CK, which was opposite for the medium and later stages. In the later stage (10 min before ending experiment), the sediment content in drainage of CK was 3.1 and 4.2 times as high as that of ZT-250 and ZT-300, respectively. During the experiment, the sediment content in drainage of the geotextiles treatments revealed a downward trend, but the CK had an upward trend. In the first and medium stages, the characteristic grain sizes of sediments in drainage of the treatments using geotextiles were higher than those of CK, while the clay content was lower than that of CK. In the later stage, the characteristic grain sizes of sediments in drainage of the treatments using geotextiles were comparable with those of CK, while the clay content of CK was between that of ZT-250 and ZT-300. Same as the trend of sediment content in drainage, the clay content of sediments in drainage of the geotextiles treatments increased, while CK decrased. The coefficient of variation of the clay content in drainage of the treatments using geotextiles was lower than that of CK, indicating that the geotextiles had stable effects on retaining sediments in glass tank. There was little difference in grain size distribution of filled surface sediments in the glass tank, but there was higher content of very fine sediments in ZT-250 and ZT-300 than that of CK. The geotextiles could increase the lateral drainage velocity of the saturated sediments and the treatment of ZT-250 had the best performance. However, the effectiveness of geotextiles on reducing sediment content in the drainage and increasing the lateral drainage velocity of the saturated sediments still need to be verified before used in the field. The research could provide valuble information for the innovation of quick drainage technology of filled Yellow River sediments in mining subsidence land located in the plain mining area with high groundwater level in Eastern China. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Infiltration
Controlled terms:Cutting machines (mining) - Drainage - Geotextiles - Glass - Grain size and shape - Groundwater - Land reclamation - Land use - Reclamation - Rivers - Sediments - Size distribution - Subsidence - Surficial sediments - Tanks (containers) - Water content
Uncontrolled terms:Coefficient of variation - Grain size - Grain size distribution - Laboratory experiments - Mining subsidence - Simulated experiments - Vertical infiltration - Yellow river
Classification code:403 Urban and Regional Planning and Development - 442.2 Land Reclamation - 444.2 Groundwater - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 502.2 Mine and Quarry Equipment - 619.2 Tanks - 812.3 Glass - 819.5 Textile Products and Processing - 922.2 Mathematical Statistics
DOI:10.11975/j.issn.1002-6819.2015.17.010
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 19>
Accession number:20154301434107
Title:Sediment, runoff, nitrogen and phosphorus losses of sloping cropland of quaternary red soil in northern Jiangxi
Authors:Chen, Xiaoan (1); Yang, Jie (1); Zheng, Taihui (1); Zhang, Jie (1)
Author affiliation:(1) Jiangxi Research Institute of Soil and Water Conservation, Nanchang, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:162-167
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In soil and water losses, 30% is from sloping cropland in China. Nutrients losses with soil losses cause poor soil productivity, especially in red soils. This study aimed to investigate the sediment and runoff losses of sloping cropland of quaternary red soil and the N and P losses in the sediments and runoff. Site-specific long-term observations have been conducted during June-October 2011 in the plots of quaternary red soil in Soil and Water Conservation Eco-technology Garden of Jiangxi (E15°42'38″-115°43'06″E, N29°16'37″-29°17'40″) located in De'an county, Jiujiang city, northern Jiangxi province. Four treatments such as bare land, downslope tillage, downslope tillage combined with hedgerow and transversal slope tillage were designed. Runoff, sediments and N and P contents were determined by collecting samples during every rainfall. The results showed that the surface runoff of bare land (15.96 mm) was highest, followed by downslope tillage (7.91 mm) and downslope tillage+ hedgerow (6.64 mm) and transversal slope tillage (2.95 mm) was lowest. Compared with downslope tillage, runoff was reduced by 62.71% by transversal slope tillage. Sediment yields of bare land (2205.5 t/km<sup>2</sup>) was highest, followed by downslope tillage (584.6 t/km<sup>2</sup>) and downslope tillage+ hedgerow (410.7 t/km<sup>2</sup>), and the sediment yields of transversal slope tillage (99.96 t/km<sup>2</sup>) was lowest. Compared with downslope tillage, sediment yields of transversal slope tillage was reduced by 82.9%. The soluble N, ammonia nitrogen, nitrate nitrogen and soluble P losses in runoff were highest for bare land, and lowest for transversal slope tillage. They in the transversal slope tillage were reduced by 53.69%, 50.84%, 46.15% and 57.47%, respectively than those in downslope tillage. The total N, total P, alkali-hydro N and available P losses in sediments were highest in the bare land but lowest in sediments of the transversal slope tillage. The organic N losses from the sloping cropland were dominated by the soluble N; while inorganic N losses were dominated by ammonia N. Moreover, the P losses in sediments accounted for most of total P losses. The study is helpful for better understanding of nutrient losses from the sloping cropland of quaternary red soil, and provide data support for protection and regulation of soil and water losses and non-point pollution from sloping cropland. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:17
Main heading:Soils
Controlled terms:Agricultural machinery - Agriculture - Ammonia - Erosion - Nitrogen - Nutrients - Phosphorus - Rain - Runoff - Sediments - Soil conservation - Water conservation - Water pollution - Wooden fences
Uncontrolled terms:Jiangxi - Long term observations - Nitrogen and phosphorus loss - Nonpoint pollutions - Red soils - Sloping croplands - Soil and water conservation - Soil and water loss
Classification code:415.3 Wood Structural Materials - 443.3 Precipitation - 444 Water Resources - 444.1 Surface Water - 453 Water Pollution - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 804 Chemical Products Generally - 804.2 Inorganic Compounds - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.1 Agricultural Machinery and Equipment
DOI:10.11975/j.issn.1002-6819.2015.17.021
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 20>
Accession number:20154301434120
Title:Ecological characteristics of Festuca arundinacea L. turf cultivated by solid residues from anaerobic digestion project
Authors:Song, Chengjun (1); Tian, Yishui (1); Luo, Juan (1); Qi, Yue (1); Zhao, Lixin (1); Zhao, Xuelan (2); Tian, Xi (3)
Author affiliation:(1) Key Laboratory of Energy Resource Utilization from Agricultural Residues (MOA), Institute of Energy and Environmental Protection, Chinese Academy of Agriculture Engineering, Beijing, China; (2) Tianjin Vocaltional College of Bioengineering, Tianjin, China; (3) Tianshui National Agricultural Science and Technology Park, Tianshui, China
Corresponding author:Zhao, Lixin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:254-260
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Biogas residue is a kind of high quality medium, being with comprehensive nutrition and rich in organic matter. In order to select new type of non-soil culture substrate, in this paper, the experiment for single factor randomized block design was carried out to study the effects of the mass fraction of biogas residue on physicochemical properties of compound organic substrate, growth characteristics of seedlings and grass turf traits of Festuca Arundinacea. In this experiment, biogas residue was used as raw material to compound organic substrate to plant tall fescue turf. The results were as follows: 1) For the T60 matrix (volume fraction of biogas residue was 60%), the total nitrogen, total phosphorus, total potassium, available nitrogen, available phosphorus, available potassium and organic matter content were the highest, and more than the other 3 matrices, which were CK, T30 and T90 (volume fractions of biogas residue were zero, 30% and 90%, respectively); with the increase of mass fraction of biogas residue in compound organic substrate, pH value of the compound matrix decreased significantly, both dry and wet bulk density decreased, both infiltration rate and total porosity increased, water retention increased, and this amelioration effect of biogas residue decreased with the increasing of mass fraction of biogas residue; 2) All 3 compound organic substrates had significant promoting effect on the seedling growth of F. Arundinacea. The seedling number per unit area growing on T90 substrate was 22242, 30616, and 31990 for the 10<sup>th</sup>, 20<sup>th</sup>, and 40<sup>th</sup>day after germination, which was increased by 54.77%, 92.01% and 91.09%, respectively, compared with CK. For the 10<sup>th</sup>day after germination, seedling height on T90 substrate was the highest, 86.36% higher than that on CK substrate. For the 20<sup>th</sup>day after germination, seedling heights on T60 and T90 substrate were the same, which were both 8 cm, 83.10% higher than that of seedling with CK substrate. In the 40<sup>th</sup>day after germination, seedling heights with T60 and T90 substrate were both 10 cm, 85.71% higher than that of seedling with CK substrate. Seedling leaf width on T90 substrate was respectively 1.34, 1.81 and 1.87cm for the 10<sup>th</sup>, 20<sup>th</sup>and 40<sup>th</sup>day after germination, and it respectively increased by 50.56%, 67.59% and 94.79% compared with that of seedling on CK substrate. From the point of view of seedling growth, both T60 and T90 substrate were suitable for the cultivation of tall fescue turf; 3) For the 10<sup>th</sup>day after germination, turf coverage on 3 compound organic substrates was higher than that of CK substrate; for the 20<sup>th</sup>and 40<sup>th</sup>day after germination, turf coverages with T60 substrate were respectively 81% and 100%, which were the highest and increased by 13.47% and 53.85% respectively compared with that of the CK substrate; the turf color and uniformity with T60 substrate was higher than that of the CK substrate; 4) For the 40<sup>th</sup>day after germination, total biomass, aboveground and underground biomass and root thickness of turf under T60 substrate were significantly greater than the other 3 substrates; root shoot ratio of turf was 3.94 on T60 substrate, which was only 28.10%, 14.53% and 7.94% of that under CK, T30 and T90 substrate, respectively. T60 substrate significantly changed the distribution of aboveground and underground biomass pattern of F. Arundinacea, and significantly promoted the biomass allocation to the aboveground. Therefore, T60 substrate was the most suitable compound organic substrate for the establishment of tall fescue turf. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Substrates
Controlled terms:Anaerobic digestion - Biogas - Biogeochemistry - Biological materials - Biomass - Chemical properties - Cultivation - Design of experiments - Ecology - Growth (materials) - Infiltration - Nitrogen - Organic compounds - Phosphorus - Physical properties - Plants (botany) - Potassium - Volume fraction
Uncontrolled terms:Available phosphorus - Available potassiums - Biogas residues - Ecological characteristics - Growth characteristic - Organic matter content - Physicochemical property - Turf-grasses
Classification code:454.3 Ecology and Ecosystems - 461.2 Biological Materials and Tissue Engineering - 522 Gas Fuels - 549.1 Alkali Metals - 641.1 Thermodynamics - 801 Chemistry - 801.2 Biochemistry - 804 Chemical Products Generally - 804.1 Organic Compounds - 821.3 Agricultural Methods - 901.3 Engineering Research - 931.2 Physical Properties of Gases, Liquids and Solids - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2015.17.034
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 21>
Accession number:20154301434123
Title:Ecological risk assessment of land destruction in large open-pit mine
Authors:Sun, Qi (1); Bai, Zhongke (1, 2); Cao, Yingui (1, 2); Xie, Miaomiao (1, 2); Hu, Xingding (1); Jiang, Yanzhu (1); Lu, Yuanqing (1)
Author affiliation:(1) School of Land Science and Technology, China University of Geosciences, Beijing, China; (2) Key Laboratory of Land Consolidation and Rehabilitation, Ministry of Land and Resources, Beijing, China
Corresponding author:Bai, Zhongke
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:278-288
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Integration management model for mining includes five steps: stripping, mining, transportation, dump piled up and reclamation. There is immediate and indirect impact on ecosystem from land destruction in mining area. In this paper, a comprehensive assessment model was used to explore the ecological risk value as exemplified by Antaibao open-pit mine of Shanxi province, China. In recent years, most researches are done for ecological risk assessment from the perspective of landscape ecology and the risk of heavy metal contamination. However less attention has been paid to the comprehensive risk assessment in the coal mining area. The mining area ecological system is easy to be disturbed and more complicated than general regions. The establishment of the ecological risk assessment model of land destruction ecological risk value (ERV) mainly includes two aspects: the effect of Antaibao opencast coal mining exploitation and ecological sensitivity of mining area. The larger environment influence of mining area by mining exploitation, the higher risk the ecological system would have. On the other hand, if the ecological system is more sensitive and fragile, the resistance and the ability to recover are lower. In this paper, we divided the study area into 30 m by 30 m grid unit and evaluated each unit to realize the mapping and classification of eco-risk in mining area. First, mining area ecological risks were identified from two aspects, production process of the mining and land destruction type in mine area. A typical open-pit mine ecological risk causal chain in Loess Plateau Region was constructed. Second, ecological index based on remote sensing and land-use type was developed specially for assessing mining area ecological sensitivity. The index was combined with six indicators which were adjusted by the important ecological indicators frequently used in assessing regional ecology and special ecological situation in mining area. Third, the data of the cumulative effect evaluation of land destruction and GIS-based ecological sensitivity evaluation were applied to quantify the comprehensive value of ecological risk. The results showed that un-reclaimed dump was the highest risk area (32.91% of the total area). Due to the reclamation measures and management for many years, reclaimed dump and industrial site were stable (9.66% of the total area). However, the unmanaged dump process and weak supervision caused soil and vegetation degradation. Therefore, some part of reclaimed dump showed a higher risk (26.46% of the total area). The open pit was the lowest risk area (30.97% of the total area). It was helpful to take the corresponding management level and constructing the preventive measures according to the risk value of different area. The occurrence of the mining area ecological risk was a dynamic process. The potential risk of disclosure may delay. This meant that we should take preventive in the process of production. If the risk occurred, it would take great harm in the mining area fragile ecosystems. Ecological risk assessment in mining area needed to be from the original single risk evaluation to the multi-level risk assessment so that we can fully embody the application value of the risk assessment as an important means mining area compound ecosystem management. This study made ecological risk assessment on the land destruction of mining area in order to realize ecological quantification and spatial visualization of the open mining and put forward the risk prevention measures for the subsequent production management. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:42
Main heading:Risk assessment
Controlled terms:Coal - Coal mines - Coal reclamation - Ecology - Ecosystems - Geographic information systems - Heavy metals - Land reclamation - Land use - Open pit mining - Reclamation - Remote sensing
Uncontrolled terms:Comprehensive assessment model - Ecological indicators - Ecological risk assessment - Ecological sensitivity - Heavy metal contamination - Opencast coal minings - Production management - Vegetation degradation
Classification code:403 Urban and Regional Planning and Development - 442.2 Land Reclamation - 454.3 Ecology and Ecosystems - 502.1 Mine and Quarry Operations - 503.1 Coal Mines - 524 Solid Fuels - 531 Metallurgy and Metallography - 903.3 Information Retrieval and Use - 914.1 Accidents and Accident Prevention
DOI:10.11975/j.issn.1002-6819.2015.17.037
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 22>
Accession number:20154301434093
Title:Effects of guide cone configuration on hydraulic performance of axial-flow pump impeller
Authors:Meng, Yu (1); Yang, Minguan (1); Li, Zhong (2); Gao, Bo (1); Ni, Dan (1)
Author affiliation:(1) Department of Energy and Power Engineering, Jiangsu University, Zhenjiang, China; (2) Eindhoven University of Technology, Eindhoven, Netherlands
Corresponding author:Yang, Minguan
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:50-56
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Axial-flow pump is widely used in Chinese agricultural production. Guide cone as an important component of impeller for axial-flow pump can enhance the flow quality of pump inlet. To find feasible design method of guide cone, investigate the influence between flow field of guide cone and that of impeller and make a preliminary exploration about rounding way of guide cone, the flow passages about six different types of guide cone with impellers were numerically simulated. The numerical simulation was based on the three dimensional incompressible Navier-Stokes equation and k-Ε turbulent model. SIMPLEC algorithm was applied to solve a discretization governing equation. Velocity of the calculation model was 2.92 m/s, and pressure of outlet was 101325 Pa. The design parameters of impeller included 5 blades, design flow of 330 m<sup>3</sup>/h, head of 5.1 m, rotating speed of 1450 r/min, diameter of impeller of 200 mm, and hub diameter of 118 mm. Based on a laboratory test performed on a DN200 test bench to measure the pumping head, discharge, and other parameters for calculation of head and efficiency, we found that the simulated and measured head and efficiency had relative error less than 4%, indicating the feasibility of the simulation method for flow field simulation of guide cones. After cooperating with the impeller, the flow field simulation results of guide cone showed that the Witozinsky guide cone was best with the highest impeller hydraulic efficiency but the circular guide cone was worst with the lowest impeller hydraulic efficiency. It indicated that the better exit flow field the guide cone flow passage had, the higher hydraulic efficiency of axial-flow pump impeller was. The rotating of impeller had effects on the uniformity of axial velocity distribution in the export section of cone flow field, but the effect of head loss and velocity weighted average drift angle was very small. The rotating of impeller also had effects on the axial-velocity distribution of outlet flow field, and little influence on radial-velocity distribution. The short distance between export section of cone with the impeller tended to increase the influence of the impeller rotating on the cross section. Appropriate increase of guide water cone length could improve the hydraulic efficiency of the impeller and the uniformity of axial velocity distribution, reduce the velocity weighted average drift angle and turbulence intensity of the export section of guide cone flow field. However, with increasing the length of guide cone, the hydraulic loss of guide cone would increase. Based on the results above in combination with practical application, we suggested that the optimal length of the guide cone with impeller was 0.5-0.7 times as impeller diameter. Meanwhile, the study showed that the adverse pressure gradient caused by the water cone sharp head could decrease the velocity of guide cone flow, which could induce the flow separation and flow disturbance. So the roundness of the water cone sharp head was necessary. After investigating the rounding coefficient, we found that the increase of water cone round length was able to reduce the hydraulic loss of guide cone and improve the impeller hydraulic efficiency. After tentative exploration, we suggested that the optimal round length of guide cone was 1/8-1/7 times as length of guide cone. The study has very important significance for the optimal design of axial-flow pump hydraulic model and the large-scale pumping station renovation. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:21
Main heading:Impellers
Controlled terms:Agriculture - Axial flow - Cyclone separators - Design - Efficiency - Flow fields - Flow separation - Hydraulic models - Navier Stokes equations - Pumps - Statistical methods - Velocity - Velocity distribution
Uncontrolled terms:Adverse pressure gradient - Agricultural productions - Axial-velocity distribution - Flow field simulation - Hydraulic efficiency - Hydraulic performance - Incompressible Navier Stokes equations - Simulation
Classification code:601.2 Machine Components - 618.2 Pumps - 631 Fluid Flow - 631.1 Fluid Flow, General - 632.1 Hydraulics - 802.1 Chemical Plants and Equipment - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 913.1 Production Engineering - 921.2 Calculus - 922.2 Mathematical Statistics
DOI:10.11975/j.issn.1002-6819.2015.17.007
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 23>
Accession number:20154301434092
Title:Numerical simulation of dynamic and similarity model test of tank in biogas fertilizer transport truck
Authors:Liu, Hongxin (1); Meng, Yongchao (1); Li, Yanlong (1); Fu, Lulu (1)
Author affiliation:(1) College of Engineering, Northeast Agricultural University, Harbin, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:42-49
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Along with China methane industry development, processing and utilization of biogas residue is an urgent need. Past studies show that biogas residue fertilizer is a high quality liquid organic fertilizer and biological pesticide. Biogas residue fertilizer transportation and fertilization in the field need biogas residue fertilizer transport tank truck. While the acres of the fertilizer application rate in the field are as high as 50 t/hm<sup>2</sup>, thus in order to improve the shipments and using efficiency of tank truck, development of a large-scale biogas residue tank truck is essential. During transportation of biogas residue fertilizer, tankers will experience starting, acceleration, constant speed, the emergency brakes driving conditions. When the tanker driving state changed, biogas residue fertilizer is forced by inertial to cause rock, which has the impact to the storage tank wall surface, and the oversized impulse causes the storage tank structure to be damaged, resulting to biogas fertilizer leakage, which brings the danger for the safe transportation. However in the driving conditions, emergency brake driving conditions will lead to the biggest damage to the tank. When a large tanker for carrying biogas residue fertilizer suffers emergency braking in its transportation of biogas fertilizer, the huge attack on the wall from biogas fertilizer's violent sway may result in damage on tank and its structure, which causes potential crisis on safety in transportation. In this paper, our results showed that the best transportation filling ratio for a tanker was in the range of 0.8~0.9 by making an analysis and numerical simulation of biogas fertilizer's sway in the tank in different filling ratios when tanker was emergently braked using VOF multiphase flow model. We established a finite element model in which there was a link-up and force delivery among components on a 3D model using CATIA finite element analysis module. We calculated the basis of tanker's actual working condition, restriction implemented and the maximum loading limit of the attack that the tanker's front seal and front washboards can support. Then we adjust tank's design and refined structure according to the computation result, and concluded that the deformation and string of tank was 6.25 mm and 136 MPa respectively. After that, we defined the geometry size and experiment parameters of tank model using dimensional analysis method of the similar theory. When the parameter design was finished, we carried out the prototypical tank trial manufacturing. After that, a high-speed camera was used to shoot biogas residue flow state in different filling ratio of the tank and at the same time high-frequency dynamic response of the pressure sensor was used to test wave proof plate. In the experiment, it was calculated that the ratio of attack from the peak surface of front washboard and the numerical simulation result in prototype was nearly 1: 64, which meant that the experiment result can be applied on prototype. This paper provided accessible solution for design of large tanker's tank which carried biogas residue fertilizer and provided reference for design of tank of similar transportation tankers. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:15
Main heading:Finite element method
Controlled terms:Agricultural machinery - Automobile testing - Biogas - Brakes - Computation theory - Computer simulation - Design - Dynamics - Fertilizers - Filling - Gas industry - High speed cameras - Numerical models - Structural analysis - Structural design - Tank trucks - Tanks (containers) - Transportation - Truck transportation - Trucks
Uncontrolled terms:Dimensional analysis methods - Experiment parameters - Fertilizer applications - High frequency dynamics - Industry development - Model tests - Multi-phase flow models - Similarity model test
Classification code:408.1 Structural Design, General - 432.3 Cargo Highway Transportation - 522 Gas Fuels - 602 Mechanical Drives and Transmissions - 619.2 Tanks - 662 Automobiles and Smaller Vehicles - 663.1 Heavy Duty Motor Vehicles - 691.2 Materials Handling Methods - 721.1 Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory - 723.5 Computer Applications - 742.2 Photographic Equipment - 804 Chemical Products Generally - 821.1 Agricultural Machinery and Equipment - 921 Mathematics - 921.6 Numerical Methods
DOI:10.11975/j.issn.1002-6819.2015.17.006
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 24>
Accession number:20154301434126
Title:Effects of phenolic xylans from wheat bran on fermented dough properties and qualities of steamed bread
Authors:Wang, Xiaoxi (1); Fan, Ling (1); Ma, Sen (1); Wang, Rui (1); Chen, Cheng (1)
Author affiliation:(1) College of Grain and Food, Henan University of Technology, Zhengzhou, China
Corresponding author:Ma, Sen
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:302-307
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to develop a natural, safe improver of steamed bread and nutrition fortifier, as well as increase the added value of wheat bran, phenolic xylans from wheat bran with different addition level (0.25%, 0.5%, 1.0%, 2.0%) and molecular weight (82°, 581kD) were chosen and their effects on fermented dough properties and qualities of steamed bread were investigated. Low molecular weight phenolic xylans were obtained by ultrasonic degradation of phenolic xylans. The rheometer and low-field nuclear resonance (NMR) were used to observe the changes of fermented dough properties with phenolic xylans. The texture profile analyzer was used to observe the changes of qualities of steamed bread with phenolic xylans. The viscoelasticity, water distribution and mobility of fermented dough, color, texture, sensory evaluation score of steamed bread were evaluated in the experiment. The results showed that along with the increase of phenolic xylans from wheat bran, the elastic modulus and proton density A<inf>22</inf>increased then decreased, viscous modulus and proton density A<inf>23</inf>increased, relaxation time T<inf>22</inf>of fermented dough decreased. The lightness and adhesiveness decreased, redness and yellowness increased, specific volume, cohesiveness, resilience and sensory score of steamed bread increased and then decreased, hardness and chewiness of steamed bread decreased and then increased with increasing addition level of phenolic xylans from wheat bran. The higher molecular weight of wheat bran phenolic xylans was, the larger quantitative change of the elastic modulus and viscous modulus would be. The high molecular weight wheat bran phenolic xylans had long relaxation time T<inf>22</inf>and small proton density A<inf>21</inf>of fermented dough. When the molecular weight of wheat bran phenolic xylans was low, the specific volume and springiness of steamed bread were large, but the hardness and chewiness of steamed bread were relatively large. Compared with the control group, the addition of phenolic xylans from wheat bran could improve the rheological properties and water properties of fermented dough and quality of steamed bread. When the content of wheat bran phenolic xylans was 0.5%, the improvement effect of fermented dough and steamed bread qualities was best. When the addition level of wheat bran phenolic xylans was lower than 1.0%, the properties of fermented dough and qualities of steamed bread were improved. However, the properties of fermented dough and qualities of steamed bread deteriorated when phenolic xylans content was 2.0%. The improvement effect of properties of fermented dough and qualities of steamed bread with high molecular weight wheat bran phenolic xylans was better than low molecular weight wheat bran phenolic xylans. The method and data stated in this study were useful and valuable to the industry and can provide the theoretical basis for phenolic xylans widely application to the flour products. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:18
Main heading:Polysaccharides
Controlled terms:Elastic moduli - Fermentation - Food products - Hardness - Molecular weight - Nuclear magnetic resonance - Quality control - Relaxation time - Viscoelasticity - Water - Water quality - Water supply systems
Uncontrolled terms:Fermented dough - High molecular weight - Low molecular weight - Phenolic xylans - Quantitative changes - Rheological property - Ultrasonic degradation - Water distributions
Classification code:445.2 Water Analysis - 446.1 Water Supply Systems - 804.1 Organic Compounds - 822.3 Food Products - 913.3 Quality Assurance and Control - 931 Classical Physics; Quantum Theory; Relativity - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2015.17.040
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 25>
Accession number:20154301434098
Title:Optimal nitrogen application rate to ensure cucumber and tomato yield with drip irrigation in greenhouse and to reduce soil salinity and nitrate residue
Authors:Wang, Liying (1, 2); Wu, Xueping (3); Zhang, Yancai (2); Li, Ruonan (2); Chen, Lili (2); Chen, Qing (1)
Author affiliation:(1) College of Resources and Environmental Sciences, China Agricultural University, Beijing, China; (2) Institute of Agricultural Resource and Environment, Hebei Academy of Agricultural and Forestry Sciences, Shijiazhuang, China; (3) Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
Corresponding author:Chen, Qing
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:91-98
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In traditional irrigation and fertilization practices, excessive water and fertilizers often cause soil salinity accumulation in greenhouse vegetable production. Drip irrigation is one of methods to accurately supply water and nutrient in root zone to meet crop needs. To determine effects of N application rate on soil NO<inf>3</inf><sup>-</sup>-N, soil electrical conductivity (EC), yield and root dry matter in greenhouse cucumber and tomato rotation, six-season experiments were conducted with drip irrigation under plastic film in greenhouse from 2008 to 2010. The experiment site was Mazhuang Experiment Station (37°18' N, 115°28' E) in Xinji city, Hebei province, China. Five treatments of no N fertilizer (NN), manure N (MN), optimal N (RN), high N (HN) and traditional N (CN) with 3 replicates each were designed. Chicken manure application rate (30 t/hm<sup>2</sup>) was applied only before cucumber season in 2008. The chemical N application rate was 0, 300, 600, 900 kg/hm<sup>2</sup>in winter-spring cucumber season and 0, 225, 450, 675 kg/hm<sup>2</sup>in fall-winter tomato season for NN, RN, HN, and CN, respectively. The yield, root dry matter, soil NO<inf>3</inf><sup>-</sup>-N, and EC were measured. The results showed that soil NO<inf>3</inf><sup>-</sup>-N and EC were significantly increased with the increase of N rate. The CN treatment accelerated and increased the soil NO<inf>3</inf><sup>-</sup>-N accumulation and soil salinity. During the 3 cucumber and tomato rotations, the average soil NO<inf>3</inf><sup>-</sup>-N content of RN, HN, and CN treatments was 176.9, 346.6, and 500.8 kg/hm<sup>2</sup>, respectively. The content of CN treatment was 2.83 times as high as RN (P<0.05). In cucumber season, soil NO<inf>3</inf><sup>-</sup>-N accumulation of RN, HN and CN treatments were -1.87, -49.61, and -3.52 kg/hm<sup>2</sup>, respectively, but 74.89, 225.23, 343.15 kg/hm<sup>2</sup>in tomato season, respectively. The CN treatment was 4.58 times as high as RN (P<0.05). After 3 rotations, soil NO<inf>3</inf><sup>-</sup>-N residual of RN, HN, and CN treatment was 219.1, 526.9, 1028.9 kg/hm<sup>2</sup>higher than before experiment, and increased by 73.0, 175.6, 339.6 kg·hm<sup>-2</sup>in each rotation. The CN treatment was 4.65 times as high as RN (P<0.05). After 3 rotations, soil EC of NN, MN, RN, HN, and CN treatment were 433.8, 681.5, 824.5, 927.5, 1120 μS/cm, respectively. Soil EC of RN, HN, and CN treatment was significantly higher than MN and NN treatment (P<0.05). Soil EC of CN treatment was 1.15, 1.29, 1.40, 1.36 (P<0.05) times as that of RN after season of tomato in 2008, cucumber in 2009, tomato in 2009 and 2010, respectively. Soil EC was decreased significantly in RN treatment compared to CN treatment, indicating optimal N management decreased the risks of soil secondary salinizaton. During each rotation, there were 2 key periods for soil NO<inf>3</inf><sup>-</sup>-N and soil EC rapid accumulation: 1) in the summer from early July to early August, and 2) early September to middle November in fruiting period of Fall-winter tomato. In sum, the optimal N rate reduced N application rate by 66.7%, decreased soil nitrate residue and soil electrical conductivity significantly, but kept the tomato and cucumber yields as high as the other high and traditional N application rate treatments. These results provide valuble information for fertigation regime in cucumber and tomato rotation of greenhouse. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Soils
Controlled terms:Electric conductivity - Fertilizers - Fruits - Greenhouses - Irrigation - Manures - Nitrates - Nitrogen - Nitrogen fertilizers - Rotation
Uncontrolled terms:Drip irrigation under plastic films - Electrical conductivity - Greenhouse vegetables - Nitrate nitrogen - Nitrogen application rates - Root dry matter - Soil electrical conductivity - Traditional irrigation
Classification code:483.1 Soils and Soil Mechanics - 701.1 Electricity: Basic Concepts and Phenomena - 804 Chemical Products Generally - 804.2 Inorganic Compounds - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 931.1 Mechanics
DOI:10.11975/j.issn.1002-6819.2015.17.012
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 26>
Accession number:20154301434127
Title:Construction and evaluation of production engineering mode for modern genuine traditional Chinese medicinal material
Authors:Sun, Junshe (1); Zheng, Zhian (2); Wang, Minjing (1); Zhang, Xiuqing (3); Luo, Jiangqing (4); Guo, Ailing (4)
Author affiliation:(1) Chinese Academy of Agricultural Engineering, Beijing, China; (2) College of Engineering, China Agricultural University, Beijing, China; (3) College of Food Science & Nutritional Engineering, China Agricultural University, Beijing, China; (4) Tianfangjian (China) Pharmacy Company Ltd., Guangzhou, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:308-314
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Traditional Chinese medicinal material is not only the material basis for the inheritance and development of Chinese medicine cause, but also a strategic resource in the national economy and people's livelihood. China is a large traditional Chinese medicinal material producer in the world, however, the issues of the planting of traditional Chinese medicinal material are becoming increasingly acute, including the lack of planting standard, imperfect management and quality and safety monitoring difficultly. Constructing scientific and systemic engineering mode for traditional Chinese medicinal material planting is more and more important for the development of Chinese herbal medicine industry. This paper involved traditional Chinese medicinal material production processes, including breeding, cultivation, harvesting and processing, storage and other links. Based on the three factors (biological factor, environmental factor and artificial factor) of genuine traditional Chinese medicinal material production, this paper put forward the hypothesis of 6 attributes of modern genuine Chinese medicinal material production, including biological nature attribute, ecological environment attribute, processing and storage attribute, character merchandise attribute, planting management attribute and quality security attribute. Based on this, through the theory, tools and methods of systematics, a new set of methodologies of 3 systems were established, including production standard system, planting management system and quality and safety system. Based on the 3 systems, the production engineering mode for modern genuine traditional Chinese medicinal material was constructed. According to the principles of science, practicality and simplicity, the realized degree evaluation index system of production engineering mode for modern genuine traditional Chinese medicinal material was established. The weights of these indices were reckoned by the use of the comparison matrix of analytic hierarchy process built in the software of MATLAB 7.6. The realized degree of traditional Chinese medicinal material planting engineering mode was evaluated by the fuzzy comprehensive evaluation method. The wood-log Ganoderma lucidum planting was used as a case study. The framework of comprehensive evaluation index system for production engineering mode of traditional Chinese medicinal material was made up of 3 grades and 19 indices. The comprehensive evaluation score of the realized degree of the wood-log Ganoderma lucidum planting was 0.71, which indicated that the engineering mode of this production presented a good level. This result was in accord with the field investigation result. The study will lay methodological foundation for the construction of production engineering mode for modern genuine traditional Chinese medicinal material and effectively guide the relative research and industry development. The result will not only has high reference value for Chinese herbal medicine production, but also provide theoretical support for the research of engineering mode of modern agricultural production. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:10
Main heading:Production
Controlled terms:Agriculture - Biological materials - Cultivation - Industrial research - MATLAB - Medical applications - Medicine - Plant extracts - Plants (botany) - Production engineering - Safety engineering - Security systems - Standardization
Uncontrolled terms:Agricultural productions - Chinese herbal medicines - Comprehensive evaluation - Comprehensive evaluation index system - Evaluation - Fuzzy comprehensive evaluation method - Medicinal materials - Mode
Classification code:461 Bioengineering and Biology - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.3 Agricultural Methods - 901.3 Engineering Research - 902.2 Codes and Standards - 913.1 Production Engineering - 914 Safety Engineering - 914.1 Accidents and Accident Prevention - 921 Mathematics
DOI:10.11975/j.issn.1002-6819.2015.17.041
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 27>
Accession number:20154301434114
Title:Estimation model of cotton yield with time series Landsat images
Authors:Liu, Huanjun (1); Meng, Linghua (1); Zhang, Xinle (1); Ustin, Susan (2); Ning, Donghao (1); Sun, Siyu (1)
Author affiliation:(1) College of Resources and Environmental Sciences, Northeast Agricultural University, Harbin, China; (2) Center for Spatial Technologies and Remote Sensing (CSTARS), Department of Land, Air, and Water Resources, University of California, Davis, United States
Corresponding author:Zhang, Xinle
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:215-220
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:At present, based on the research of crop yield, estimation of time series of MODIS_NDVI is widely used, but the MODIS data by the spatial resolution of the sensor and features of complex types of limitations has a great influence on the monitoring effect. In this paper, we used Landsat_5_TM and Landsat_7_ETM images of 30 m spatial resolution, constructed a multi day synthetic vegetation index time series data. Two cotton plots in San Joaquin Valley of California were studied to predict cotton yield with the vegetation index. San Joaquin Valley is the Mediterranean climate that belongs to the high yield region of cotton. Landsat_5 and Landsat_7 images combined with the field measured data were used to establish cotton yield prediction model. The tendency of the normalized difference vegetation index (NDVI) and the enhanced vegetation index (EVI) time series and the correlation between vegetation index and cotton yield were analyzed to acquire the optimal cotton yield estimation phase. Then the optimal yield prediction model of cotton was built. Through comparison of the two vegetation indexes respectively as independent variable, the precision of the model can be found. With NDVI as input variable, the decision coefficient and root mean square error were slightly better than EVI. So in this paper, we selected NDVI as yield estimation factor. The results showed that the time series of NDVI based on pure pixels of Landsat images can reveal the period of cotton growing exactly. NDVI of different stages of cotton growth showed differences with time changing, especially in cotton flowering and boll-setting period with 30 m spatial resolution. The correlation coefficient between the flowering and boll-setting period of NDVI and cotton yield was larger than 0.80, and the maximum correlation coefficient was 0.90. During flowering and boll-setting period, NDVI average value determination coefficient of model was 0.82, RMSE was 463.69, thus using flowering and boll-setting stages was more suitable for cotton yield prediction than other growth stages. The NDVI on July 25th was the optimal model input variable for single period, and the average of three growth stage NDVI value before the maximum NDVI was the optimal model input variable for multiple growth stages, and we used the average of NDVI value in the whole flowering and boll-setting stages as input variable for the model. The determination coefficient (R<sup>2</sup>) reached 0.82; and the R<sup>2</sup>was 0.81, RMSE was 477.82 with the model of taking the maximum NDVI value as input variable. The correlation coefficient was large between NDVI of any time in the flowering and boll-setting growth stage and the cotton yield. Thus any growth stage during the flowering and boll-setting period can be used to predict cotton yield. In addition, in the study area, we chose the model of the plot A to verify the plot B model. We concluded that RMSE was 387.53, compared with the common modeling RMSE value, and the test result was ideal. The research results of this paper provided the theoretical basis for the research on the maximum synthesis of MODIS_NDVI. It provided a reference for other crops to establish the yield estimation model. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:18
Main heading:Cultivation
Controlled terms:Cotton - Crops - Forecasting - Image resolution - Mean square error - Models - Remote sensing - Time series - Vegetation
Uncontrolled terms:Correlation coefficient - Determination coefficients - Enhanced vegetation index - Flowering and boll-setting period - LANDSAT - Maximum correlation coefficient - NDVI - Normalized difference vegetation index
Classification code:821.3 Agricultural Methods - 821.4 Agricultural Products - 922.2 Mathematical Statistics
DOI:10.11975/j.issn.1002-6819.2015.17.028
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 28>
Accession number:20154301434089
Title:Calculation and modification by experiment of driving force for vertical impact sprinkler
Authors:Tang, Pan (1); Li, Hong (1); Chen, Chao (1); Zou, Chenhai (1)
Author affiliation:(1) Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang, China
Corresponding author:Li, Hong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:20-26
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:At present, the most representative and most widely used sprinkler is high pressure vertical impact sprinkler. The magnitude of driving force, an important evaluation indicator, influences not only the stress distribution and service life of the sprinkler but also the stability of the running sprinkler. In order to improve the accuracy of calculated driving force of vertical impact sprinkler, in this paper, we modified the theoretical calculation equations of driving force through the experimental test results, and presented the correction coefficient transformation equations on the basis of the theoretical equations for calculating horizontal driving force and vertical driving force, and verified the amended equations of calculating the driving forces. Moreover, the advanced testing system was used to measure the driving force of vertical impact sprinkler. Our research results showed that the assumed conditions had a relatively significant impact on the calculation of the driving force in the process of theoretical derivation, which caused a large deviation in theoretical values. The maximum deviation was about 20% between the driving force of horizontal direction and that of vertical direction especially under low working pressure. The deviation of the theoretical calculation decreased with the increase of working pressure both in the horizontal and vertical directions. Meanwhile, this also showed that the correction coefficient of theoretical equation was not a constant, and it changed with the working pressure of the sprinkler. The horizontal calculation deviation decreased considerably with the increase of working pressure and the calculation values of horizontal driving force had better accuracy under high pressure, while the vertical calculation deviation was less than the horizontal calculation deviation as the working pressure increased. The overall calculation deviation was relatively large. Subsequently, on the basis of the theoretical equations for calculating horizontal and vertical driving forces, the correction coefficient transformation equations were obtained through the regression analysis of experimental data and were relatively higher in accuracy. The determination coefficient R<sup>2</sup>was 0.9799 and 0.9289 for horizontal and vertical, respectively. In addition, the correction coefficients were in an exponential and logarithmic relationship respectively with the working pressure in its calculation equations of the horizontal driving force and the vertical driving force. In the theoretical calculation, the deviation of the driving force presented a reverse relationship with the working pressure as the diameters of sprinkles varied. Within the variation range of measuring parameters, the maximum deviations were 23.99% and 31.08% in the theoretical calculation of vertical driving force and horizontal driving force, respectively. It showed that the theoretical calculation equation of the vertical driving force was higher than that of the horizontal driving force in accuracy before the amendment of the theoretical calculation equations. After the amendment, the obtained values of the vertical driving force and the horizontal driving force were approximate to the experimental values with the deviation less than 5%, showing that the amended equations for calculating driving forces were higher in accuracy. This study provided reference for designing and optimizing the rocker arm and the drive vane of the vertical impact sprinkler. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:17
Main heading:Metadata
Controlled terms:Calculations - Digital storage - Nozzles - Pressure - Regression analysis
Uncontrolled terms:Correction coefficients - Correction factors - Determination coefficients - Driving forces - Impact sprinklers - Logarithmic relationship - Theoretical calculations - Transformation equationss
Classification code:722.1 Data Storage, Equipment and Techniques - 921 Mathematics - 922.2 Mathematical Statistics - 931.1 Mechanics
DOI:10.11975/j.issn.1002-6819.2015.17.003
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 29>
Accession number:20154301434125
Title:Partition coefficient model of papain in PEG/PEG-IDA-Fe<sup>3+</sup>/(NH<inf>4</inf>)<inf>2</inf>SO<inf>4</inf>affinity aqueous two-phase system
Authors:Peng, Jian (1); Zhang, Haide (1); Jiang, Mengshi (1); Xu, Yinghao (1); Cai, Tao (1); He, Yuqin (1); Wen, Nana (1)
Author affiliation:(1) Department of Food College, Hai Nan University, Haikou, China
Corresponding author:Zhang, Haide
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:295-301
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Aqueous two-phase systems (ATPSs) are formed by 2 materials with different structures, such as polyethylene glycol (PEG) and dextran or a polymer and a salt. Possessing many important advantages such as short processing time, low energy consumption, relative reliability in scale-up and biocompatibility in environment, ATPSs are widely used for separation and purification of various proteins and nucleic acids. Based on this theory, the metal affinity aqueous two-phase systems have been reported which introduced the metal ion to PEG to enhance the efficiency of the extraction. Papain (EC3.4.22.2) is an endolytic cysteine protease obtained from the latex of papaya (Carica papaya), which can catalyze the hydrolysis of peptide bonds composed by basic amino acids. As its wide pH span for optimum activity, high sensitivity, temperature stability, low price and short response time, papain has been extensively used in medicine, cell, detergents, leather, textiles, cosmetic and food fields, and played an important role in our daily life. With the development of purification technology, more and more novel ATPSs have been used for the extraction of papain. However, most researchers have focused on the optimization of partitioning conditions and scarcely concentrated on the papain's partition model, especially the partition model in affinity aqueous two-phase systems. Overall, the papain partition behavior in ATPSs is affected by the type and concentration of polymer and salt, the environment temperature, the pH value and the substance for separation. The effect of pH value on papain activity and the effect of PEG-IDA-Fe<sup>3+</sup>on enzyme activity were investigated in this paper. Results showed that the pH value of 4.0-9.0 had little effect on enzyme activity and the papain activity could reach the highest (3478 U/mg) at the pH value of 7.0, while PEG-IDA-Fe<sup>3+</sup>would restrain papain activity slightly. To ensure the partition behavior of papain in PEG/PEG-IDA-Fe<sup>3+</sup>/(NH<inf>4</inf>)<inf>2</inf>SO<inf>4</inf>affinity ATPS was selective and predictable, the triangular phase diagrams of ATPSs were measured by means of cloud point under 298.15 K. Two kinds of triangular phase diagrams showed that 10% PEG-IDA-Fe<sup>3+</sup>replacement had little effect on the phase diagram. Experiments can be conducted according to the 2 kinds of phase diagrams. Based on the correlation between the logarithm of the partition coefficient and the concentration difference of each component, the partition model of papain in PEG/(NH<inf>4</inf>)<inf>2</inf>SO<inf>4</inf>ATPS was established. The mean relative deviation of the equation model was 7.02% which was less than other similar models. In addition, the impact factor was introduced to PEG/PEG-IDA-Fe<sup>3+</sup>/(NH<inf>4</inf>)<inf>2</inf>SO<inf>4</inf>system to establish affinity partition model of papain. The relative errors between the experimental and predicted values of the partition coefficient were less than 15%, which could represent the affinity partition behavior of papain in PEG/PEG-IDA-Fe<sup>3+</sup>/(NH<inf>4</inf>)<inf>2</inf>SO<inf>4</inf>system. The results in this paper indicate that the new model is potential for predicting papain's partition coefficient in metal chelated ATPSs. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Papain
Controlled terms:Amino acids - Biocompatibility - Energy utilization - Enzyme activity - Enzymes - Extraction - Metal ions - Metals - Models - Nucleic acids - pH - pH effects - Phase diagrams - Polyethylenes - Purification - Soaps (detergents) - Solvent extraction
Uncontrolled terms:Aqueous two phase system - Environment temperature - Low energy consumption - Partition coefficient - Separation and purification - Short processing time - Temperature stability - Triangular phase diagram
Classification code:461.9 Biology - 461.9.1 Immunology - 525.3 Energy Utilization - 531.1 Metallurgy - 801.1 Chemistry, General - 802.3 Chemical Operations - 804.1 Organic Compounds - 815.1.1 Organic Polymers
DOI:10.11975/j.issn.1002-6819.2015.17.039
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 30>
Accession number:20154301434099
Title:Effects of alternative irrigation with brackish and fresh water on cotton yields and solute transport in soil
Authors:Huang, Jinou (1, 2); Jin, Menggui (1, 2); Li, Xianwen (2, 3)
Author affiliation:(1) State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China; (2) School of Environment Studies, China University of Geosciences, Wuhan, China; (3) Department of Hydraulic Engineering, Tongji University, Shanghai, China
Corresponding author:Jin, Menggui
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:99-107
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In arid or semi-arid areas, brackish water is often used for irrigation because of water shortage and soil nutrient deficiency. However, irrational irrigation with brackish water may lead to the accumulation of saline ions such as sodium, which might inhibit plant growth or even crop failure. In this study, we investigated the relationship between different irrigation methods and crop growth and yield in order to find a proper method of irrigation and fertilization. In order to achieve this objective, 2 years of field experiments in 2012 and 2013 were conducted at the experimental station in Korla, Xinjiang, China. Three irrigation treatments with brackish water, fresh water and alternative irrigation (20% of fresh water at bud and early boll stages, 80% of brackish water at late boll and boll opening stages) in the whole growing season were designed. Cotton and soil samples (from 0-100 cm depth) were collected in 4 days after the last irrigation. Cotton root were sampled with square monolith method in the space of 70 cm×20 cm×50 cm. Root length density was estimated with DT-SCAN software. Available content of copper, iron, magnesium, calcium, potassium, and sodium in soil samples were extracted with Mehlich 3 reagent. Element content of cotton bolls were extracted after wet acid digestion (HNO<inf>3</inf>-HClO<inf>4</inf>-HF). Then, they were determined in triplicate by inductively coupled plasma optical emission spectrometer (ICP-OES). Accumulation coefficient was defined as the ratio of nutrient content in soil layers of 0-10 cm or 0-20 cm to that in 0-100 cm, representing the element aggregation capability in topsoil. The results showed that when sodium did not accumulate in 2012, irrigation with brackish water significantly enlarge (compared to results in fresh water) the aboveground dry matter, numbers of bolls per unit area, and seed cotton yields by 32%, 20%, and 22%, respectively. Nevertheless, continuous irrigation using brackish water under heavy application of nitrogen fertilizer resulted in the surface aggregation of sodium, which significantly inhibited the root growth as well as aboveground dry matter and the yields. From 2012 to 2013, the total root length density decreased significantly under the brackish water treatment, which led to a sharp reduction of the aboveground dry matter, the numbers of bolls per unit area, and the seed cotton yields (P<0.05). In this case, the root length density, the aboveground dry matter, the numbers of bolls per unit area, and the seed cotton yields were improved by 12%-24% compared to the results for the brackish water treatment under the alternative irrigation. Moreover, the alternative irrigation did not essentially solve the problem of nutrient deficiency under the traditional cultivation pattern, thus a sustainable scheme of irrigation and fertilization should be made according to the solute variation in the soil. The average copper, iron, and magnesium in the soil profile reduced by 40% from 2012-2013 and the accumulation coefficients varied from 0.14-0.17 to over 0.20; however, the average calcium, potassium, and sodium increased by 33%-45% in the soil profile. For all treatments, calcium and potassium did not gather in the topsoil, whereas sodium under the brackish water treatment changed from weak to strong aggregation in the surface. This result provides valuble information for the rational irrigation and fertilization with brackish water in cotton cultivation. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Water treatment
Controlled terms:Agglomeration - Calcium - Copper - Cotton - Crops - Cultivation - Forestry - Inductively coupled plasma - Irrigation - Magnesium - Nitric acid - Nitrogen fertilizers - Nutrients - Pollution detection - Saline water - Soil pollution - Soil surveys - Soils - Solute transport - Water
Uncontrolled terms:Brackish water - Root - Salinity - Temporal and spatial variation - Yield
Classification code:444 Water Resources - 445.1 Water Treatment Techniques - 483.1 Soils and Soil Mechanics - 544.1 Copper - 549.2 Alkaline Earth Metals - 802.3 Chemical Operations - 804 Chemical Products Generally - 804.2 Inorganic Compounds - 821.3 Agricultural Methods - 821.4 Agricultural Products - 931 Classical Physics; Quantum Theory; Relativity - 932.3 Plasma Physics
DOI:10.11975/j.issn.1002-6819.2015.17.013
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 31>
Accession number:20154301434112
Title:Hyperspectral mixed pixel decomposition policy merging simple linear iterative clustering
Authors:Zhang, Feifei (1, 2); Sun, Xu (2); Xue, Liangyong (3); Gao, Lianru (2); Liu, Changxing (1)
Author affiliation:(1) Surveying Science and Technology, Xi'an University of Science and Technology, Xi'an, China; (2) Institute of Remote Sensing and Digital Earth, Computer Science and Technology, Chinese Academy of Sciences, Beijing, China; (3) Computer Science and Technology, China University of Mining and Technology, Xuzhou, China
Corresponding author:Sun, Xu
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:199-206
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The decomposition efficiency of mixed pixels is an important subject in the research of remote sensing application. Current mature extraction algorithms of the endmember are pure pixel index (PPI), N-FINDR, vertex component analysis (VCA), sequential maximum angle convex cone (SMACC), alternating volume maximization (AVMAX), minimum volume enclosing simplex (MVES), etc. Extracting pure spectra from all pixels of an image by those algorithms has relatively slow processing and low accuracy. Therefore, in this paper, we introduced an integration of simple linear iterative clustering (SLIC) super pixel segmentation of hyperspectral mixed pixel decomposition algorithm. The number of pixels in a hyperspectral image was one of the main reasons that affected pixel unmixing (especially endmember extraction). Super pixel segmentation techniques can compose adjacent pixels with similar characteristics into image blocks, and retain useful information for further image processing, thus significantly reducing the number of pixels involved in endmember extraction and solving the problems of low processing and low accuracy in an effective way. In this paper, endmember extraction method was modified. We used Simple Linear Iterative Clustering (SLIC) algorithm to segment hyperspectral image pixels into super pixel sets, and conducted experimental comparisons on impact of different dimension reduction methods such as principal components analysis (PCA), minimum noise fraction (MNF), correspondence between different RGB (six kinds), different color spaces (RGB, LAB), different data formats(JPG, BIN)and different algorithms' parameters K on hyperspectral image super pixel segmentation results. Furthermore, the impact of SLIC super pixel segmentation results on two typical endmember extraction algorithms was analyzed. The results showed that, with the increase of K value, the decomposition of mixed pixels gradually increased. The reason for such change was that as the K value increased, the number of pixels increased, and the size of the image was reduced and was close to a normal pixel. The JPG (lossy compression) data format of time was shorter than BIN (lossless compression) data format because a lossy compression can reduce the image size occupied in memory or disk space. The root-mean-square error (RMSE) of SLIC+MVES was slightly higher than that of MVES, and lower than that of AVMAX, with the time much less than actual MVES. In other words, relative to MVES, SLIC+MVES greatly increased processing speed, at the expense of a small amount of sacrifice in accuracy. AVMAX consumed little time itself because it did not need to solve linear programming problems repeatedly. So after adding super pixel segmentation, the time shortened for AVMAX was not significant, but the time for SLIC computing had increased. When increasing K, the computation time increased gradually, and the RMSE was flat or deceasing. When K was large enough, the results of SLIC+MVES was approximate to that of MVES. The difference in the RGB color space and Lab color space was not obvious. SLIC algorithm used Lab color space because it did not rely on the advantages of the device, but also had its own advantages, i.e., a wide color gamut. In most cases, dimensionality reduction by MNF was better than that of PCA. As to the MNF dimensionality reduction method, the data in JPG format, with Lab color space were more favorable for unmixing results. In addition, the value of SLIC parameters from 5 to 10 was more appropriate. The SLIC super pixel segmentation algorithm was simple and improved the efficiency of unmixing, with a great practical value. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Pixels
Controlled terms:Algorithms - Bins - Clustering algorithms - Color - Cones - Data compression - Efficiency - Extraction - Image analysis - Image compression - Image processing - Image segmentation - Iterative methods - Laboratories - Linear programming - Mean square error - Principal component analysis - Reduction - Remote sensing - Spectroscopy - Spectrum analysis
Uncontrolled terms:Decomposition of mixed pixels - Dimensionality reduction method - Endmember extraction algorithms - Iterative clustering - Linear programming problem - Principal components analysis - Remote sensing applications - Super pixels
Classification code:694.4 Storage - 741.1 Light/Optics - 802.2 Chemical Reactions - 802.3 Chemical Operations - 903.1 Information Sources and Analysis - 913.1 Production Engineering - 921.6 Numerical Methods - 922.2 Mathematical Statistics
DOI:10.11975/j.issn.1002-6819.2015.17.026
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 32>
Accession number:20154301434087
Title:Simulation of cultivated land conversion trend and its effect on carbon budget in China
Authors:Jiang, Dongmei (1); Li, Xiaoshun (1, 2, 3); Qu, Futian (2); Yan, Jinming (3); Wang, Yunjia (1); Zhang, Shaoliang (1); Shi, Xiaoping (2); He, Guancong (1)
Author affiliation:(1) Key Laboratory for Land Environment and Disaster Monitoring of SBSM, China University of Mining & Technology, Xuzhou, China; (2) China Land Problem Research Center, Nanjing Agricultural University, Nanjing, China; (3) Department of Land Management, Renmin University of China, Beijing, China
Corresponding author:Li, Xiaoshun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:1-9
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Along with the rapid industrialization and urbanization, China is undergoing increasingly aggravated cultivated land conversion. Consequently, it causes great damage to environment and the worsening of the greenhouse effect. Therefore, this paper puts the cultivated land conversion and carbon budget into a unified framework, and uses the system dynamics method to simulate and measure the carbon budget change caused by the farmland conversion from 1996 to 2020. Using the system dynamics software Vensim, the carbon budget system model based on cultivated land conversion is built, which emphasizes the population subsystem, economic subsystem, cultivated land subsystem and construction land subsystem. Then the dynamic behavior of each system is simulated and the change law is revealed. Firstly, through simulating and comparing the data of the cultivated land and construction land from 1996 to 2020, it is found that the cultivated land conversion is concentrated in the eastern region, and the area of China's cultivated land is decreasing while the construction land is increasing. The simulation results indicate that the area of cultivated land has reduced from 1.293×10<sup>8</sup>hm<sup>2</sup>in 1996 to 1.204×10<sup>8</sup>hm<sup>2</sup>in 2020, and the construction land has increased from 2.407×10<sup>7</sup>to 3.073×10<sup>7</sup>hm<sup>2</sup>. Secondly, in the process of simulating the national carbon budget, the paper mainly selects the 4 variables which are construction land green area, ecological restoration, cultivated land and construction land. And their carbon sink/source correlation coefficients are obtained from previous research. The carbon budget measurement shows that from 1996 to 2020, the carbon sink based on national cultivated land conversion reduces from 7.90×10<sup>8</sup>to 7.48×10<sup>8</sup>t, the carbon source increases from 9.34×10<sup>9</sup>to 1.17×10<sup>10</sup>t, and the national carbon budget of the cultivated land conversion generally presents that the carbon expenditure increases from 8.55×10<sup>9</sup>to 1.10×10<sup>10</sup>t. Thirdly, the paper divides China into 4 regions (northeast, east, center and west) and makes regional comparison. The selection and estimation of parameters are similar to the whole country. The regional simulation results show that the carbon expenditure in the east is 3.569×10<sup>9</sup>t, in the west is 2.065×10<sup>9</sup>t, in the central is 1.991×10<sup>9</sup>t, and in the northeast is 8.99×10<sup>8</sup>t in 1996; and in the year 2020, the carbon expenditure in the east is 5.029×10<sup>9</sup>t, in the west is 2.261×10<sup>9</sup>t, and in the central is 2.216×10<sup>9</sup>t, and in the northeast is 1.084×10<sup>9</sup>t. And the capacity of carbon sink will be decreasing in 4 regions, the carbon source will be increasing significantly in future, and the carbon budget will present carbon expenditure which is predicted to increase but the increase is not huge. By comparison, the carbon source and carbon budget in east will increase mostly. The carbon sink, carbon source and carbon budget will be stable in northeast. So, the imbalance status of carbon budget in China is mainly caused by the eastern region. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:35
Main heading:Budget control
Controlled terms:Carbon - Emission control - Greenhouse effect - Land use - System theory
Uncontrolled terms:Carbon sink - Carbon source - China - Correlation coefficient - Cultivated lands - Dynamic behaviors - Ecological restoration - Estimation of parameters
Classification code:403 Urban and Regional Planning and Development - 451 Air Pollution - 451.2 Air Pollution Control - 804 Chemical Products Generally - 961 Systems Science
DOI:10.11975/j.issn.1002-6819.2015.17.001
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 33>
Accession number:20154301434105
Title:Spatial-temporal stability distribution characteristics of soil moisture in gravel-sand mulched field in northwestern arid area
Authors:Zhao, Wenju (1); Li, Xiaoping (1); Fan, Yanwei (1); Yu, Wen (1); Tang, Xuefen (1)
Author affiliation:(1) School of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:144-151
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Gravel-sand mulched field in northwestern arid area has a history of more than 300 years, but little is known about spatial-temporal dynamics of soil moisture, which is important for prediction of soil moisture. Therefore, in this study, we designed a field experiment to investigate dynamics of soil moisture in Experiment Station of Lanzhou University of Technology, Lanzhou, China. The experiment started from May 18 to August 3 in 2013. A field in width and length of 32 m was meshed by 4-m for soil sampling in each mesh grid. A total of 64 sampling points was designed. Soil samples were collected from the points at 0-10, 10-20, 20-30, and 30-50 cm for 12 times during the experiment. Based on the data, models were established for soil moisture prediction. Then, a similar experiment was conducted to collect samples to validate the model established in 2013. The results showed that the variability of surface soil moisture was largest and soil moisture distribution was in small patch-like pattern. The variability of soil moisture decreased with the increase of soil depth. Variation trend of mean soil moisture and coefficient of variation kept consistent over time in different soil layers. Mean soil moisture was 11.70% in 0-10 cm, 14.99% in 10-20 cm, 13.26% in 20-30 cm and 12.49% in 30-50 cm, respectively, indicating a upward trend with soil depth. However, the coefficient of variation was 0.2068 in 0-10 cm, 0.1821 in 10-20 cm, 0.1483 in 20-30 cm and 0.1241 in 30-50 cm, respectively, showing a downward trend with soil depth. The variation of soil moisture was largest in 0-10 cm. In addition, the study found that fragmentation degree of soil moisture distribution under dry condition was higher than wet condition, and temporal stability was high with the increase of soil depth. The relative deviation of soil moisture lied between -26.94% and 21.89% in 0-10 cm, between -23.40% and 17.26% in 10-20 cm, between -18.24% and 13.33% in 20-30 cm, between -15.73% and 11.60% in 30-50 cm. The standard deviation of the average relative deviation lied between 11.71% and 23.15% in 0-10 cm, between 10.85% and 22.18% in 10-20 cm, between 8.77% and 21.27% in 20-30 cm, between 6.96% and 17.35% in 30-50 cm. Spatial-temporal stability of soil moisture increased with the increase of soil depth. Based on information above, the representative measuring points of point 1, point 1, point 44, point 36 were selected for soil moisture estimation for 0-10, 10-20, 20-30 and 30-50 cm. The correlation coefficient between the estimated by representative measuring points and measured values was 0.877-0.968, and standard error and average deviation were small. Linear regression models were established based on the representative measuring points and validated by data obtained from 2014. The relative error between measured value and predicted value lied between 5.18% and 0.59% in 0-10 cm, between 15.42% and 0.55% in 10-20cm, between 1.07% and 10.33% in 20-30 cm, between -12.87% and 0.07% in 30-50 cm. It suggested that the prediction accuracy of models was high and the representative measuring points could be used for soil moisture estimation in the study area. The results provide valuble information for measuring point layout for soil moisture and accurate prediction of soil moisture in the study area. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:23
Main heading:Soil surveys
Controlled terms:Arid regions - Drought - Forecasting - Gravel - Moisture - Moisture meters - Regression analysis - Sampling - Soil moisture - Soils - Stability
Uncontrolled terms:Dynamics of soil moistures - Gravel sands - Lanzhou University of Technology - Relative deviations - Soil moisture distribution - Soil moisture estimation - Soil moisture predictions - Spatial temporals
Classification code:443 Meteorology - 444 Water Resources - 483.1 Soils and Soil Mechanics - 922.2 Mathematical Statistics - 944.1 Moisture Measuring Instruments
DOI:10.11975/j.issn.1002-6819.2015.17.019
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 34>
Accession number:20154301434116
Title:Copper loss-minimized remedial control algorithm of fault-tolerant flux-switching permanent-magnet motor
Authors:Zhao, Wenxiang (1); Zhang, Bufeng (1); Ji, Jinghua (1); Tang, Jianxun (1); Liu, Guohai (1)
Author affiliation:(1) School of Electrical and Information Engineering, Jiangsu University, Zhenjiang, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:228-234
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:For agricultural motor drive applications, reliability and continuity are very significant, and even under fault condition, continuing the drive operation is essential. Multiphase motors can keep on operating with the remaining healthy phases when open-circuit fault occurs in one or two phases and operating without any other hardware under fault condition. Fault-tolerant flux-switching permanent-magnet (FT-FSPM) motor is a new multiphase stator permanent-magnet fault-tolerant machine which incorporates the merits of high fault-tolerant capability. In this paper, a new remedial control is proposed for a five-phase FT-FSPM motor under open-circuit fault of stator windings to improve efficiency and reliability of the motor drives. Based on the principle of copper loss minimization, the aim of this strategy is to keep output torque unchanged and minimize output torque ripple. A field-circuit co-simulation model is developed and an experimental platform is set up, which are used to evaluate torque performances of 10/19-pole FT-FSPM motor drive under various conditions. Simulated and experimental results will be used for verifying the proposed remedial control method. First, based on the analysis of the structure characteristics of FT-FSPM motor, the fault-tolerant current equations are proposed, in which copper loss is minimized and torque capability is maintained. Second, aiming at the performances of motor current, speed and torque response, the simulation of FT-FSPM motor has been carried out on the basis of Maxwell/Simplorer. In order to assess the normal and faulty operations of the FT-FSPM motor drive, the co-simulation technique is adopted in which the magnetic circuit and the electric circuit are coupled in the time domain, thus providing the convenience of system-level simulation. The modeling tools for the co-simulation are composed of 2 separate packages, namely, the magnetic solver Maxwell 2-D and the circuit solver Simplorer. The magnetic solver performs finite-element analysis (FEA) of the FT-FSPM motor, while the circuit solver performs electric circuit analysis of the power converter. At each time step of co-simulation, the magnetic and circuit solvers exchange the calculated data, and the results produced by one solver will be exported to the other solver in the next step. Consequently, the system performances can be accurately predicted. The simulated results show that the torque can be kept the same as normal and the torque ripple decreases to 13.7% under fault condition when adopting the presented control strategy, while the torque ripple is 33.3% without adopting the strategy. Third, a digital signal processing is used to implement the control for this experiment. A separately excited DC (direct current) generator is used as the variable load. To measure the torque of the proposed motor drive, a transient torque transducer is mounted between the five-phase FT-FSPM machine and the DC generator. Moreover, the currents are sensed by the Hall-effect sensors and the position signal is obtained by the optical encoder with an accuracy of 2048 counts per revolution. It can be found that the torque performance is very good under fault-tolerant condition from the experimental results. Also, it verifies that the FT-FSPM motor drive can successfully perform self-starting capability under the open-circuit fault. From the comparison between simulated and experimental results, it shows that the proposed control strategy can reduce the copper losses, maintain the torque performance and minimize the torque ripple during the open-circuit fault. The correctness and effectiveness of the proposed remedial control strategy are verified. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Electric machine theory
Controlled terms:Agricultural machinery - Algorithms - Control - Copper - Coupled circuits - Digital storage - Electric drives - Electric generators - Electric motors - Electric network analysis - Electric windings - Fault tolerance - Finite element method - Magnetism - Magnets - Motors - Networks (circuits) - Permanent magnets - Signal processing - Stators - Time domain analysis - Torque
Uncontrolled terms:Copper loss-minimization - Efficiency and reliability - Fault tolerant control - Fault-tolerant capability - Fault-tolerant machines - Flux switching motors - Motor drive applications - Structure characteristic
Classification code:544.1 Copper - 701.2 Magnetism: Basic Concepts and Phenomena - 703.1 Electric Networks - 703.1.1 Electric Network Analysis - 704.1 Electric Components - 705 Electric Generators and Motors - 716.1 Information Theory and Signal Processing - 722.1 Data Storage, Equipment and Techniques - 821.1 Agricultural Machinery and Equipment - 921 Mathematics - 921.6 Numerical Methods - 931.2 Physical Properties of Gases, Liquids and Solids
DOI:10.11975/j.issn.1002-6819.2015.17.030
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 35>
Accession number:20154301434106
Title:Runoff erosion process on slope of engineering accumulation with different soil-rock ratio
Authors:Shi, Dongmei (1); Jiang, Guangyi (2); Peng, Xudong (1); Wang, Sanshu (3); Li, Yexin (1); Jiang, Ping (1)
Author affiliation:(1) College of Resources and Environment, Southwest University, Chongqing, China; (2) Chongqing Eco-Environment Monitoring Station of Soil and Water Conservation, Chongqing, China; (3) Chongqing Surveying and Design Institute of Water Resources, Electric Power and Architecture, Chongqing, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:152-161
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Engineering accumulation, a kind of loose soil-sock mixture consisted of soil, parent rock and stone caused by various artificial engineering during producing and constructing process, is the most serious erosion-landform in production and construction areas because it can greatly change the terrain, soil and vegetation conditions of original landform in a very short term, thereby causing great soil and water loss under a certain rainfall-runoff condition, and making more difficult for ecological restoration in these project areas. In order to revel the runoff erosion mechanism and its process for engineering accumulations with different slopes and soil-rock ratios, we carried out field scouring experiments from August to November 2012 at the Soil Erosion Experiment Site for production and construction projects in Southwestern University, Chongqing (29° 48'50.2"N, 106° 24'48.8"E). The field scouring experiments were conducted under the simulated runoff conditions according to the regional rainstorm occurrence frequency with the 5, 10, 15, 20, 25 L/min for purple soil deposits and 5, 7.5, 10, 12.5, 15 L/min for yellow sand deposits, respectively. In the experiment, some physical properties, hydraulic properties and runoff erosion process on underlying surfaces of engineering accumulations with different producing sources and soil-rock ratios were all comparatively studied. The results indicated that material composition and infiltration capacity of the two loose engineering accumulations were remarkably different from original landform. The yellow sand deposit was dominated by ≤0.25 mm particles with particles variation coefficient as high as 1.2-2.0 times than its original landform and its stable infiltration rate was 1.70-4.07 times than original landforms, respectively; while purple soil deposit was well-distributed, its' variation coefficient of particles was 2.2 times than original landform and the stable infiltration rate was 7.02-11.59 times than original landforms. The experiments also showed that soil-rock ratio change could influence the slope infiltration performance for the two engineering accumulations and the effects of engineering construction on the purple soil deposits were more powerful than that of the yellow sand deposits. Some dynamic parameters on underlying surfaces of engineering accumulations increased with increasing flow discharge, in which flow velocity of yellow sand deposits ranged from 0.155 to 0.318 m/s, flow shear stress varied between 27.632 and 57.154 N/m<sup>2</sup>, and soil detachment rate changed from 0.337 to 77.071 g/(m<sup>2</sup>·s); while the flow velocity, flow shear stress and soil detachment rate of purple soil deposits were 0.184-0.281 m/s, 35.525-53.600 N/m<sup>2</sup>and 1.445-61.910 g/(m<sup>2</sup>·s), respectively. For rocky underlying surfaces, runoff yield rate had continuously waving variations within 9 min after runoff yielded. When flow discharge increased gradually from 5 to 25 L/min, the average runoff yield rate of rock underlying surface from yellow sand deposit increased by 510.38%, 531.96 % and that of purple soil deposit increased by 73.20% and 57.61%, respectively; for same conditions, the cumulative runoff of underlying surfaces showed the similar trend of partial soil deposits larger than rocky deposits, and that of yellow sand deposit higher than purple soil deposit. For rocky underlying surfaces, sediment yield rate presented continuously multi-peak multi-valleys. When flow discharge increased from 5 to 25 L/min gradually, the average sediment production rate of rock underlying surface from yellow sand deposit were 0.001, 0.03, 0.542 kg/(m<sup>2</sup>·min), respectively, while that of purple soil deposit were 0.0003, 0.012, 0.034 kg/(m<sup>2</sup>·min), respectively. The collapse on gully wall caused by gravity from underlying surfaces was an important cause for the fluctuating variations of the sediment yield rate. These results provide essential parameters and technical supports for predicting soil water loss caused by production and construction projects and for selecting vegetation measures for soil and water conservation in similar areas. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Infiltration
Controlled terms:Deposits - Erosion - Flow velocity - Flowmeters - Geomorphology - Hydrodynamics - Landforms - Rocks - Runoff - Sand - Sediments - Shear flow - Shear stress - Soil conservation - Soil moisture - Soils - Storms - Surface properties - Vegetation - Water conservation
Uncontrolled terms:Construction projects - Ecological restoration - Engineering constructions - Infiltration capacity - Material compositions - Sediment production rate - Soil and water conservation - Variation coefficient
Classification code:443.3 Precipitation - 444 Water Resources - 444.1 Surface Water - 481.1 Geology - 481.1.1 Geomorphology - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 631 Fluid Flow - 631.1 Fluid Flow, General - 943.1 Mechanical Instruments - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2015.17.020
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 36>
Accession number:20154301434113
Title:Rape plant NDVI 3D distribution based on structure from motion
Authors:Zhang, Yanchao (1); Zhuang, Zaichun (1); Xiao, Yuzhao (1); He, Yong (1)
Author affiliation:(1) College of Biosystem Engineering and Food Science, Zhejiang University, Hangzhou, China
Corresponding author:He, Yong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:207-214
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Plants' morphology changes in their growing process. There is a great need of plant's morphology study for future use like biomass estimation, illness and insect infestation, genotype and other agricultural applications. For now, 3D reconstruction methods can get plants' morphology information. It is meaningful to integrate organic matte distribution information in 3D model. NDVI has been proved to an important index in remote sensing and has a close relationship with chlorophyll density. In this work, Tetracam ADC multispectral camera was used. It is a broadband multispectral camera which has 3.2 million pixels in Bayer filter layout on CMOS photosensitive unit. Thirty one multispectral images of a rapeseed plant were collected at three different angles under indoor conditions for 3D reconstruction. The rapeseed plant must remain stationary and background must keep unchanged. A chessboard was added to the scene for control length comparison and to increase background texture detail. The photos equally surrounded rapeseed plant and covered every corner of the scene. Computer vision method, i.e. Structure from motion (SFM) was used to process plant's 3D model. Visual SFM was used for 3D reconstruction and the generated dense point cloud contains 120089 3D points. It worked in the following four steps: 1) extraction of SIFT points, an average of 2490 SIFT points of image were found; 2) motion estimation; 3) bundle adjustment, 3D sparse point cloud contained 3345 points with color were built; 4) dense point cloud generation, point cloud contained 120089 points with R-G-NIR information were built. The point cloud had a lot of outliers, so a statistical outlier removal method was used for filtering. The removed outliers were 2682 points. Control length from chess board was used to measure 3D model accuracy. The RMSE of spatial uniformity was 0.052599, and the maximum error was 0.1023 cm. The result showed that this 3D model precisely represented rapeseed plant's morphology. The last step was to extract xyz and r-g-nir data from point cloud, to calculate every point's NDVI and to visualize plants' NDVI spatial distribution. The result generated from Visual SFM was a ply format file which contained 10 fields not only xyz-rgb. So six fields of x-y-z-r-g-nir were extracted from original data and NDVI index of every point was calculated. The histogram of rape 3D model's NDVI showed the amount of point distributed on every NDVI value. As the NDVI value of background chessboard paper and desktop were below 0, their NDVI were set 0. To visualize the NDVI spatial distribution, a pseudo-color transform was performed according to color transformation theory. After pseudo color transformation, NDVI values were transformed into RGB color and the result ply file containing six field x-y-z-r-g-b. The results showed that the attempts to integrate multispectral image information into plant 3D reconstruction worked out well and had a potential for plants' organic matters spatial distribution research. Compare to other 3D reconstruction method like structure-light 3D reconstruction and laser scanning, SFM had less limitations including no need for special instrument and accessory; good reconstruction result; and being able to integrate NIR information in the point cloud. In the future, this method can be used for insects and illness positioning, plant stress reaction and some similar study. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Image reconstruction
Controlled terms:Algorithms - Cameras - Color - Computer vision - Image processing - Infrared devices - Morphology - Motion estimation - Oilseeds - Remote sensing - Spatial distribution - Statistics
Uncontrolled terms:3D reconstruction - Background textures - Color transformation - Images - Multi-spectral cameras - Multispectral images - Rape plant - Structure from motion
Classification code:741.1 Light/Optics - 741.2 Vision - 742.2 Photographic Equipment - 821.4 Agricultural Products - 921 Mathematics - 922.2 Mathematical Statistics - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2015.17.027
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 37>
Accession number:20154301434104
Title:Effects of biochar on hydraulic parameters and shrinkage-swelling rate of silty clay
Authors:Zhao, Di (1); Huang, Shuang (1); Huang, Jiesheng (1)
Author affiliation:(1) State Key Laboratory of Water Resources and Hydropower Engineering Science, School of Water Resources and Hydroelectric Engineering, Wuhan University, Wuhan, China
Corresponding author:Huang, Shuang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:136-143
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Biochar is an effective soil amendment. Its effects on soil chemical properties have been widely studied but little is known about its influence on soil hydraulic properties. In this study, we aimed to investigate sizes and addition proportion of biochar on silty clay loam. The loam was collected from 0-10 cm paddy field in Qujialing research base of State Key Laboratory of Water Resources and Hydropower Engineering Science (which located on Jingzhou City, Hubei province). Two kinds of biochar sizes were designed including fine biochar with size of 0.013-0.048 mm and coarse biochar with size of 0.3-0.7 mm. They were added to loam in two ratios of 3% and 6%, respectively. The hydraulic parameters and shrinkage-swelling rate of silty clay loam were determined. The centrifugal method was used to measure soil water characteristic curves, and vernier caliper was used to measure shrinkage properties in the process of the centrifugation. Results showed that: 1) Both fine and coarse biochar addition could decrease water retention ability of tested soil, but the effects of biochar sizes and addition ratios were not significantly different; Biochar addition increased the proportion of very fine (<0.3 μm) and middle-large (>30 μm) pores in total pores, but increased that of minor and small pores (≥0.3-30 μm); Fine biochar addition could enhance development of pores ≥0.3-5 μm while coarse biochar addition facilitated pore development of ≥5-30 μm; In general, addition ratios did not significantly affect pore distribution; 2) Biochar application decreased the saturated moisture content and wilting coefficient of tested soil but increased effective moisture content in soil; Fine biochar had the highest capacity to increase soil effective moisture, and the effects were not affected by biochar addition ratios; Soil water holding capacity was greatly affected by coarse biochar addition but not by fine biochar addition, and coarse biochar could decrease water holding capacity; 3) Both fine and coarse biochar decreased the soil shrinkage rate during centrifugal process, and the effect of fine biochar on shrinkage rate of soil was more significant than that of coarse biochar; 4) Fine biochar had no effect on swelling rate of soil, and coarse biochar decreased swelling rate of soil; 5) Biochar application decreased saturated hydraulic conductivity of soil; 6) The treatments of 3% and 6% biochar addition rates both for fine biochar and coarse biochar didn't show significant difference in most of the parameters studied here. Therefore, 3% biochar addition rate was recommended for practical application. In conclusion, biochar addition shows positive and negative influences on soil. For example, it could decrease saturated hydraulic conductivity of soil, thereby affecting rice production. It is necessary to alleviate the adverse effects by other drainage measures in field. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:35
Main heading:Soils
Controlled terms:Centrifugation - Hydraulic conductivity - Moisture - Moisture determination - Shrinkage - Soil moisture - Swelling - Water resources
Uncontrolled terms:Bio chars - Saturated hydraulic conductivity - Silty clay - Soil hydraulic properties - Soil-water characteristic curve - Water characteristics - Water resources and hydropower engineering - Water retention ability
Classification code:444 Water Resources - 483.1 Soils and Soil Mechanics - 632.1 Hydraulics - 802.3 Chemical Operations - 944.2 Moisture Measurements - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2015.17.018
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 38>
Accession number:20154301434101
Title:Prediction model of saline of soil and its validation based on thermal infrared emissivity spectrum
Authors:Kelimu, Ardak (1, 2); Tiyip, Tashpolat (1, 2); Zhang, Fei (1, 2); Lei, Lei (1, 2); Zhang, Dong (1, 2)
Author affiliation:(1) College of Resources and Environment Science, Xinjiang University, Urumqi, China; (2) Key Laboratory of Oasis Ecology under Ministry of Education, Xinjiang University, Urumqi, China
Corresponding author:Tiyip, Tashpolat
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:115-120
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In arid and semi-arid inland areas, due to high evapotranspiration, the minerals in the soil water accumulation in the soil surface, soil salinization becomes a serious threat to the local agricultural production, ecological stability and economic development. At present, most research on remote sensing technology to monitor the saline soil is focused on quantifying the relationship between the saline soil salt content and its associated, environmental factors or human factors and visible-near infrared, thermal infrared, or microwave remote sensing data. In this paper, we took the Ebinur Lake in the northeast of Junggar Basin Xinjiang as the study area. Thermal infrared emissivity spectra unique characteristics were used to determine the degree of soil salinization. First, we used the platform of FTIR (Fourier Transform Infrared Spectrometer) temperature and emissivity separation processing software to separate temperature and emissivity in order to obtain the original soil emissivity spectral data. Then, the spectrum smoothing iterative method was used to separate the soil emissivity and thermometers for elimination of environmental and human-caused errors when collecting spectral emissivity data in order to get the real soil emissivity spectral information. After that, we used Gaussian filter smoothing method to filter noise spectral data. In addition, we mixed the pure soil with salt to achieve five different soil salt contents: 0.1, 2.3, 9.7, 26.22, 49.8 g/kg soil and a pure soil with no salt addition, and analyzed the thermal infrared emissivity spectral characteristics of them. The raw spectral data from them were de-noised by square root transformation, logarithmic transformation, the first derivative, and the second derivative. The four transformations were compared in their normalized ratio, and we determined the relationship between spectral data and soil salinity. We also used stepwise multiple regression equation to establish six different forms of forecasting models. By comparing the models of analysis, the establishment of the square root transformation had the highest prediction accuracy and R<sup>2</sup>was greater than 0.82. By use of stepwise multiple regression model for each data set, the modeling results very stable, and test sample coefficient of determination R<sup>2</sup>=0.82, the root mean square error(RMS) is 0.92. Prediction model had performed very well, between the Ebinur basin of thermal emissivity spectra of soil salinizaiton in square root transformation and salt content has exist a function form. In this study, we discussed the hyperspectral remote sensing monitoring technology that can be used to predict the soil salt in Ebinur Lake basin, it provided the technical methods for the large-scale, low-cost and real-time monitoring the soil salinity. Such variation of emissivity method would promote the development and application of hyperspectral remote sensing technology monitoring on the space-time dynamic of arid land saline soil for future regional ecological restoration. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:20
Main heading:Soils
Controlled terms:Agriculture - Data flow analysis - Ecology - Electromagnetic wave emission - Environmental technology - Filtration - Forecasting - Fourier transform infrared spectroscopy - Infrared devices - Infrared radiation - Iterative methods - Lakes - Mean square error - Metadata - Regression analysis - Remote sensing - Salts - Separation - Soil moisture - Space optics - Spectrum analysis - Statistical tests
Uncontrolled terms:Emissivity spectra - Salinization - Soil salinity - Stepwise multiple regression - Thermal infrared
Classification code:454 Environmental Engineering - 454.3 Ecology and Ecosystems - 483.1 Soils and Soil Mechanics - 711 Electromagnetic Waves - 741.1 Light/Optics - 801 Chemistry - 802.3 Chemical Operations - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921.6 Numerical Methods - 922.2 Mathematical Statistics
DOI:10.11975/j.issn.1002-6819.2015.17.015
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 39>
Accession number:20154301434110
Title:Energy-efficient aquaculture environmental monitoring system based on ZigBee
Authors:Yang, Xuhui (1, 2); Zhou, Qingguo (2); Han, Genliang (1); Zheng, Bo (1); Zhang, Hongxia (1); Bu, Shijie (1); Xu, Wude (1)
Author affiliation:(1) Gansu Province Key Laboratory of Sensors and Sensing Technology, Institute of Sensor Technology, Gansu Academy of Sciences, Lanzhou, China; (2) School of Information Science & Engineering, Lanzhou University, Lanzhou, China
Corresponding author:Zhou, Qingguo
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:183-190
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:China's aquaculture industry develops rapidly in recent years, but most of the aquaculture environmental monitoring is still in the level of traditionally relying on artificial experience, and its cost is high and efficiency is low, and has been unable to meet the demand of the current development of aquaculture. This paper, based on ZigBee wireless sensor network technology, designed a kind of energy-efficient aquaculture environmental monitoring system to monitor the water temperature, pH value, dissolved oxygen concentration and turbidity parameters. The paper designed the wireless sensor node using CC2530 as the core processor, designed the A/D conversion module and RF (radio frequency) module by using A/D conversion function and RF function of CC2530, and designed the signal conditioning circuit based on electrochemical sensor. The system supplied electricity for wireless sensor nodes using the 9 V lithium battery to realize the wireless system, developed the node application program using the open source protocol stack Z-stack to improve the system stability and reliability, developed the local user monitoring interface and remote monitoring site using the mixed programming mode of C/S and B/S, constructed the dynamic self-organizing network based on the mesh topology, prolonged the survival time of node using time-sharing and subarea power supply mode and data fusion technology. The paper established the mathematical model from the power of the node modules, and then put forward a kind of energy-saving technology from the 2 aspects of hardware and software. After the design of the node, the paper verified the theoretical calculation through laboratory experiment and field experiment. In laboratory, the comparison experiment of 4 types of schemes of the system energy consumption was carried out. Laboratory tests showed that it doubled the life of nodes when using the time-sharing and subarea power supply for each module of the node. It prolonged the life of node by about 50 h when reducing the amount of data transmission to sink node. The result showed that the electrochemical sensor and signal conditioning circuit used in the system have become the dominant factors of the sensor node power consumption, and the data transmission capacity has become the secondary factor. In order to improve the accuracy of the measurement of the aquaculture parameters, and not lose the useful information, after the analysis of laboratory test data, the best plan was chosen and the experiment was carried out in the field. In the field, system worked for 3 months. Then, the discharge test of the lithium battery of the nodes was carried out. The result showed that the remaining energy of the 12 sensor nodes was about 66% of the total energy, that of the 3 routing nodes was about 47% of the total energy and that of the 1 routing node was about 33% of the total energy. The results of the field test were consistent with the laboratory, and the energy-saving technology was practicable. Therefore, the system has the advantages of low power consumption, stable operation, long network lifetime, and so on. It can realize the real-time monitoring of aquaculture environment, and has the very good market prospect and promotion value. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:19
Main heading:Monitoring
Controlled terms:Analog to digital conversion - Application programs - Aquaculture - C (programming language) - Computer systems programming - Data communication systems - Data fusion - Data transfer - Dissolved oxygen - Electric batteries - Electric discharges - Electric power systems - Electric power utilization - Electrochemical sensors - Energy conservation - Energy efficiency - Energy utilization - Environmental engineering - Environmental technology - Laboratories - Lithium batteries - Low power electronics - Open source software - Open systems - Power management (telecommunication) - Sensor data fusion - Sensor nodes - Sensors - Signal conditioning circuits - Strain measurement - System stability - Wireless sensor networks - Zigbee
Uncontrolled terms:Dissolved oxygen concentrations - Energy efficient - Energy-saving technologies - Environmental Monitoring - Environmental monitoring system - Stability and reliabilities - System energy consumption - Theoretical calculations
Classification code:454 Environmental Engineering - 525.2 Energy Conservation - 525.3 Energy Utilization - 701.1 Electricity: Basic Concepts and Phenomena - 702.1 Electric Batteries - 702.1.1 Primary Batteries - 706.1 Electric Power Systems - 722 Computer Systems and Equipment - 723 Computer Software, Data Handling and Applications - 801 Chemistry - 821.3 Agricultural Methods - 943.2 Mechanical Variables Measurements - 961 Systems Science
DOI:10.11975/j.issn.1002-6819.2015.17.024
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 40>
Accession number:20154301434109
Title:Agricultural environment monitor system based on UAV and wireless sensor networks
Authors:Zhang, Bo (1, 2); Luo, Xiwen (1); Lan, Yubin (1); Huang, Zhihong (2); Zeng, Ming (2); Li, Jiyu (1)
Author affiliation:(1) Engineering Research Center for Agricultural Aviation Application, Guangzhou; Guangdong, China; (2) Modern Education and Technology Center, South China Agricultural University, Guangzhou, China
Corresponding author:Luo, Xiwen
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:176-182
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The wireless sensor network (WSN) technology has been evolving very quickly in recent years. Sensors are constantly improved in their sensing, processing, storage, and communication capabilities. In a larger scale hilly land agricultural environment monitor WSN, a pure multi-hop approach to route the data all the way along the network, which can extend for hundreds or even thousands of kilometers, can be very costly from an energy dissipation point of view. In order to significantly reduce the energy consumption used in data transmission and extend the network lifetime, we presented a three-tier framework for monitoring agricultural environment using TUFSN(Three-tire Unmanned aerial vehicle Farmland Sensor Network)where data collection and transmission were done using Unmanned Aerial Vehicles (UAVs) in South China. In the system, we defined three types of nodes, which included: sensor nodes, relay nodes, UAVs. In the sensor nodes, a classic WSN one-hop or multi-hop routing approach to transmit their data to the nearest RN was used, which acted as a cluster head for its surrounding sensor nodes. Then, an UAV was moved along the pre-defined route or optimizing route that transported the data collected by the RNs to the data center. The TUFSN was divided into three layers, which included: the lower layer for acquisition data based on relay node and sensor node, the middle layer of relay transmission based on sensor node and UAV, and the upper layer for moving aggregation based on UAV and data center. This architecture led to considerable savings in node energy consumption, due to a significant reduction of the transmission ranges by use of a one-hop or the least hop between sensor node and relay nodes and the transmission to communicate the data by use of a one-hop from the relay nodes to the UAV. Furthermore, the strategy provided reduced interference between the relay nodes that can be caused by hidden terminal and collision problems, which would be expected if a pure multi-hop approach was used at the relay node level. We evaluated the performance of the architecture by some simulation. Our simulation of investigating the impacts on some parameters included: flying speed, flying height, flying time, relay node buffer size, UAV buffer size and relay node communication radius. Simulation and test results showed that, 1) when flying at the speed of 1 m/s, UAV should fly much lower to get enough time for communication with relay node; 2) when the communication radius of relay node was higher than 30 m, UAV could have more than 45s for communication; 3) when the buffer size of each relay node increased, UAV needed to fly more slow or fly more lower; 4) when relay node communication radius increased, UAV could fly more high or fly more quickly; and 5) when the transition ratio was 2000 bps, the range of relay node's cache was 3-13kB. We hoped that our simulation provided some guidelines on large scale hilly country farmland data collecting systems. A set of experiments were carried out in the Teaching and Research Farm of South China Agricultural University in April 2015, with the purpose of demonstrating the effectiveness of the proposed system. The experiments were limited to eight relay nodes which were separated from each other at a distance of 150 m. There were two or three sensor nodes surround every relay node. It should be highlighted that sensor nodes can only communicate with the closest relay node. The eight rotors of the UAV attached mobile node flied at a speed of 1 m/s and 15 meters altitude in the experiment. Statistical results indicated that the average communication time for UAV and each relay nodes were 26 seconds. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Sensor nodes
Controlled terms:Agriculture - Crashworthiness - Data acquisition - Digital storage - Energy dissipation - Energy utilization - Farms - Interference suppression - Monitoring - Network architecture - Unmanned aerial vehicles (UAV) - Vehicle transmissions - Vehicles - Wireless sensor networks
Uncontrolled terms:Agricultural environments - Communication capabilities - Communication radius - Communication with relays - Data collecting system - Farmland - Teaching and researches - Three-tier framework
Classification code:525.3 Energy Utilization - 525.4 Energy Losses (industrial and residential) - 602.2 Mechanical Transmissions - 652.1 Aircraft, General - 722 Computer Systems and Equipment - 723.2 Data Processing and Image Processing - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 914.1 Accidents and Accident Prevention
DOI:10.11975/j.issn.1002-6819.2015.17.023
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 41>
Accession number:20154301434108
Title:Simulation and validation of critical nitrogen dilution curve for summer maize in Guanzhong Plain during different rainfall years
Authors:Qiang, Shengcai (1); Zhang, Fucang (1); Xiang, Youzhen (1); Zhang, Yan (1); Yan, Shicheng (1); Xing, Yingying (1)
Author affiliation:(1) Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education, Institute of Water-Saving Agriculture in Arid Areas of China, Northwest A&F University, Yangling, China
Corresponding author:Zhang, Fucang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:17
Issue date:September 1, 2015
Publication year:2015
Pages:168-175
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Guanzhong plain of Shaanxi Province is one of the main productions of summer maize, and faces 2 problems: 1) Annual and seasonal large rainfall variability can significantly affect dry matter accumulation of summer maize and growth; and 2) Nitrogen fertilizer is excessively applied because the increase of nitrogen rate application does not synchronize with the increase of maize yield, but lead to a series of environmental problems. The existing crop nitrogen diagnostic tool is time-consuming and costly, so exploring simple and practical techniques for scientific nitrogen application is necessary such as nitrogen dilution curve. In this study, we constructed nitrogen dilution curves and validated its feasibility to diagnose nutrient status in Guanzhong plain. Six summer maize varieties and four nitrogen levels N<inf>0</inf>(0), N<inf>1</inf>(86 kg/hm<sup>2</sup>), N<inf>2</inf>(172 kg/hm<sup>2</sup>) and N<inf>3</inf>(258 kg/hm<sup>2</sup>) were applied to the study. The study was carried out in College of Water Resources and Architectural Engineering, Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education Northwest A&F University, Yangling, Shaanxi China (108°24'E, 34°20'N) in 2013 and 2014. These two years were different with normal rainfall at early stage and drought at late stage in 2013 but drought in early stage and flooding in late stage in 2014. Aboveground biomass, nitrogen content and yield of summer maize were determined. Based on dry matter, the critical nitrogen dilution curves for summer maize were developed and validated. Results showed that exponential function with two parameters including critical N concentration for 1 ton dry matter (CC) and changes of critical N concentration (CR) could be used to describe relationships between the nitrogen concentration and the aboveground biomass in 2 years. In 2013, CC values were 21.91 and 22.3 for dry matter larger and lower than 1.5 t/hm<sup>2</sup>; in 2014, CC values were 21.91 and 26.5 for dry matter larger and lower than 0.63 t/hm<sup>2</sup>, respectively; The CR values were 0.31 and 0.14 for the year of 2013 and 2014, respectively. The models were validated using data of another maize variety. The standardized root mean square error was 8.8% and 14.1% for the year of 2013 and 2014, indicating that the model fitness was well. The model parameter CC was not affected by years with different rainfall conditions. However, the parameter CR was greatly affected by years in that the value was higher in 2013 than 2014. Based on the critical N dilution curves, nitrogen nutrition index (NNI) was calculated to quantify the nitrogen nutrition status in main growth period of summer maize. The diagnostic results showed that NNI increased with N application rate and it was higher in 2014 than in 2013. The NNI was less than 1 for N<inf>0</inf>treatment, indicating N deficiencies, but greater than 1 in N<inf>3</inf>treatment, indicating excess N application. By analyzing relationship between NNI and relative yield, it was found that the optimal N application rate was 172 kg/hm<sup>2</sup>in 2013. The results can be used for the diagnosis of N nutrition in maize. It also can provide a key technical approach to precise N fertilization management in summer maize production in Guanzhong Plain. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:42
Main heading:Nitrogen fertilizers
Controlled terms:Diagnosis - Dilution - Drought - Ecology - Exponential functions - Fertilizers - Grain (agricultural product) - Mean square error - Nitrogen - Nutrition - Precipitation (chemical) - Rain - Water resources
Uncontrolled terms:Architectural engineering - Arid and semi-arid areas - Guanzhong Plain - Nitrogen concentrations - Nitrogen dilution curves - Nitrogen nutrition - Simulation and validation - Summer maize
Classification code:443.3 Precipitation - 444 Water Resources - 454.3 Ecology and Ecosystems - 461.6 Medicine and Pharmacology - 461.7 Health Care - 802.3 Chemical Operations - 804 Chemical Products Generally - 821.4 Agricultural Products - 921 Mathematics - 922.2 Mathematical Statistics
DOI:10.11975/j.issn.1002-6819.2015.17.022
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.