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Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at upgrading the regional industrial structure and achieving efficient use of water resources, this paper used relevant analysis theory and grey system theory to study the relationship between industrial structure and water consumption. On the basis of determination of the direction of industrial structure optimization, an industrial structure optimization model considering water carrying capacity was constructed, optimized the regional industrial structure under different level years, determined the industrial optimization scheme and analyzed them. The proportion of industrial structure in 2025 and 2030 will be 1.28:36.78:61.94 and 1.13:35.88:62.99, respectively. The model optimization results show that the optimized industrial structure of Zhengzhou in the future level years will improve the efficiency of water resources utilization. [ABSTRACT FROM AUTHOR]

Copyright of Study on Optical Communications / Guangtongxin Yanjiu is the property of Study on Optical Communications Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to improve the performance of greenhouse control system and figure out the multi-time scale variable problem between plant growth and environment elements in greenhouses, the ensemble empirical mode decomposition (EEMD) and Elman neural network were used to predict cayenne pepper height in this paper. Taking the cayenne pepper 8819 and its plant height and environment elements (temperature, relative humidity, total inner radiation) as research object, plant height and environment elements were decomposed by the method of EEMD. The cayenne pepper plants sampled were irrigated with the nutrient solution with electricity conductivity of 2.0 and pH value of 6.5 from Shandong Agricultural University. Five intrinsic mode functions (imfs) were obtained by the EEMD, named imf1, imf2, imf3, imf4 and imf5. Oscillations of cayenne pepper plant height and environment elements at different frequency were shown by imf1, imf2, imf3 and imf4, while variation trend of cayenne pepper plant height and environment elements were shown in imf5. All imfs were reconstructed by reconstruction of the EEMD with approximate values of 1, 0 and 0 respectively for correlation coefficient, standard error and mean absolute error to original time series. The imfs obtained by EEMD decomposition were used to build plant height prediction model at different time-scale frequencies based on EEMD method and Elman neural network. All the plants of cayenne pepper 8819 sampled were divided into 2 sets, which were training set and testing set. Average values of sampled plants and environment elements were used in neural network building. In this paper, the environment elements (temperature, relative humidity and inner total radiation) formed the input layer of EEMD-Elman network, and the prediction of cayenne pepper plant height was the output layer of EEMD-Elman network. Double-layer feedback structure method was used in this paper, in which there were 10 nodes in the first layer and 3 nodes in the second layer. The function ‘transig’ was used as transfer function in the feedback layer, while the function ‘purelin’ was used in the output layer. Sample data were divided into training set, validation set and testing set in proportion of 0.7:0.15:0.15. Five sub-neural networks were established by imf1, imf2, imf3, imf4 and imf5 of samples’ plant height and environment elements. Final predicted value of sampled plant height was reconstructed by EEMD reconstruction, using the results of 5 sub-neural networks. Results of EEMD-Elman prediction model showed the mean absolute error for plant height was 1.69 cm, with the correlation coefficient of 0.996 and the standard error of 1.104, which meant the prediction value was significantly correlated to the real value. Otherwise, 2 different prediction models were built by the method of EEMD-BP (back propagation) neural network and Elman neural network. Results of EEMD-BP prediction model showed the mean absolute error of 5.40 cm for plant height, with the correlation coefficient of 0.812 and the standard error of 7.012, while results of Elman model showed the mean absolute error of 8.87 cm, with the correlation coefficient of 0.908 and the standard error of 5.032. The results of 3 different prediction models were compared. The prediction of EEMD-Elman neural network was the best among the 3 neural networks. The results of the models with EEMD were better than that of the Elman model without EEMD. So, EEMD could decompose time series into different time scales according to its own features without the disturbance of noises and singular wave signals. Details of original time series were demonstrated decently by EEMD. Fluctuation of original time series could be explained better at different time scales by EEMD. Precision of prediction could be improved by Elman neural network with double-layer feedback structure construction. In conclusion, the combination of EEMD and Elman neural network can be used to figure out the issue of the prediction of multi-time scale between plant growth and environment variation in greenhouses, in order to provide effective references for control objectives optimization in greenhouse control system. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Harbour Engineering is the property of Editorial Office of China Harbour Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Due to the short technical research period in the early stage, many single or special designs issues for Sanhekou Hydro-Junction have limited the process of constructing, such as the insufficient depth, unreality and environmental barriers. In the bidding and constructing stage, the proprietor unit standard from the overall situation and optimized the whole design in time. The optimization indicates that they have shortened the construction duration for 13 months and saved the investor for more than 70 millions Yuan, meanwhile it have improved the construction management efficiency dramatically. This paper analyzed and summarized the construction organization and design optimization results of Sanhekou water Conservancy project from the aspects of concrete mixing system, traffic scheme, slag field, raw material dam foundation excavation, etc. which provided useful reference for similar- engineering constructions. [ABSTRACT FROM AUTHOR]

China is rich in crop straw resources, but straw burning is serious and resource utilization is not high. To solved the ecological pollution and resource waste caused by straw burning, and let straw carbonization equipment market promotion. The orthogonal experiment of carbonization process was designed according to the literature and the results of preliminary experiment. The straw biochar produced by process test was analyzed. The thermal characteristic parameters and combustion characteristic parameters were calculated. Straw biochar yield, fuel ratio, hydrocarbon atomic ratio, alkalinity index, high calorific value and dimensionless comprehensive combustion index Z were used as quality evaluation indexes for high quality straw biochar. Grey correlation analysis method and comprehensive quality score method were used to analyze the evaluation indexes and influencing factors, and the response surface method designed by CCD experiment was used to optimize the production process of straw biochar directional regulation. The experiment provides a theoretical basis for improving the energy utilization rate of straw and provides a large number of data support for the popularization and application of continuous straw carbonization equipment. The results showed that temperature was the primary factor affecting the quality of straw biochar. The five evaluation indexes of straw biochar quality except the yield of straw biochar were ranked as follows: Z > H/C >FR >AI >HHV, the quality of straw biochar produced by the equipment is stable and close to the burning quality of bituminous coal. In the orthogonal experiment, the experiment in group 16 and group 12 obtained a higher comprehensive score, and the optimal process parameter combination was A3B4C1. CCD test results after response surface optimization, in the balance of the two response values to meet the maximum, the predicted optimal process parameters are: cut after the corn straw, after 600 ℃ thermal carbonization for 50 min, the production of straw biochar output is 53.05%, its combustion index Z is 0.726 6. The empirical test showed that the difference between the experimental value and the predicted value was less than 0.2%, the fitting model and the response surface optimization method were accurate and feasible, and the combustion quality of straw biochar produced by the optimal carbonization process was greatly improved. The C content and H/C of straw biochar produced under the best technological conditions are increased by nearly 2 times, which is closed to the combustion quality of bituminous coal and anthracite, and far better than the barbecue biochar purchased in the market. Through the carbonization process in this study, the utilization quality of straw biochar can be controlled directionally, forming a reproducible and generalized quasi-directional regulation method of high quality fuelized straw biochar. The analysis methods greatly reduce the experiment times, choose the appropriate fuel straw biochar quality evaluation index, and on the premise of saving the cost of raw materials and energy, quick understanding of high quality energy straw biochar production process parameters, facilitate continuous piecewise uniform crop straw carbonization market-oriented all-round production system of rapid popularization and application.In addition, the experimental design and data analysis method in this paper can also provide data support for the production of straw carbonization process using straw as raw material for adsorption and fertilizer carbon. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mechanical precision seed metering device is widely used in precision seeding technology because of its simple structure and uniform seed metering. Seed filling process is the key link of the whole operation process of seed metering device. The precision metering device is mainly divided into internal filling, side filling, external filling, and the combination of side filling and external filling according to the seed filling mode. In the operation process, the internal filling mode mainly completes the seeding operation through the process of type-hole filling and gravity clearing, and the seed motion parameters close to the type-hole directly affect the seeding quality of the machine. The rotary type-hole cotton precision seed metering device is a kind of mechanical precision seed metering device. In order to solve the problem of missing seed in the process of filling, the influence of the motion parameters of rotary type-hole cotton precision seed metering device on the filling performance by establishing the kinematic model of the seed filling process in this paper. Using the discrete element simulation software to analyze the speed change trend of cotton seed falling into the type-hole and the influence of seed wheel vibration frequency on seed group disturbance. Taking the vibration frequency of seed wheel, vibration offset angle of seed wheel and rotating speed of metering device as the test factors, and taking the qualified rate of seed spacing, replaying rate and missing rate as the test indexes, three factors and five levels of positive traffic rotation combined test are carried out to explore the influence of each factor on seed metering performance. Design expert 8.0.6 software is used to analyze the test results and optimize the regression model. Single factor simulation test results show that the instantaneous speed of cotton seed increases with the increase of the rotating speed of the seed wheel, the instantaneous speed of the cotton seed is less than that of the seed wheel when it is filled into the type-hole, the cotton seeds with lower relative speed have better filling effect. When the vibration frequency of the seed wheel is 7 Hz, the average value of the normal force of the seed group is the smallest, which is 0.75 N, at this time, the internal friction of the seed goup is the smallest, the cotton seed is easy to be taken by the type-hole, and the seed filling performance of the seed metering device is improved. The simulation results of quadratic regression general rotation combination show that when the rotating speed of the seed metering device is 12.59 r/min, the vibration offset angle of seed wheel is 8.06° and the vibration frequency of seed wheel is 6.08 Hz, the qualified rate of seed spacing reaches the maximum of 94.5%, and the leak seeding rate is 2.9%, the repaly rate is 3.3%. On this basis, the platform validation test was carried out with Xinluzao No.61 cotton seed as the test object. The test results showed that when the rotating speed of the seed metering device was 12 r/min, the maximum qualified rate of the seed spacing was 94.65%, the error between the rotating speed of the seed metering device and the simulation test is 5.4%, which verifies the accuracy of the simulation results. This study can provide a reference for the structural optimization of the key components of the rotary type-hole cotton precision metering device. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Computational Mechanics / Jisuan Lixue Xuebao is the property of Chinese Journal of Computational Mechanics Editorial Office, Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Policy & Complex Systems is the property of Policy Studies Organization and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Natural Gas & Oil is the property of Editorial Department of Natural Gas & Oil and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nonferrous Metals (Mineral Processing Section) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Secretary (16742354) is the property of Secretary Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mountain Research (10082786) is the property of Mountain Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to further strengthen the construction of experimental technical team, and to provide a strong support for teaching, scientific research and personnel training in colleges and universities, according to the existing problems in the construction of experimental technical teams in colleges and universities, such as the status of the team is not high, the position is unclear, the management system is backward, and the post responsibility is not clear and so on, this paper combines the experimental technical team of Guangdong University of Technology with the demand of the “high level university” to the experimental technical team, puts forward a precise calculation method and the fine post setting scheme to solve the problem of the experimental technical team in time, and establishes the incentive mechanism of the experimental technical team. At the same time, after more than two years of practice, facing on the shortcomings of the calculation scheme model, the article puts forward the scientific optimization strategy and solution to effectively crack the difficult problems of the experimental technical team. It may provide a reference basis for the reform path of the experimental technology in the science and engineering colleges. [ABSTRACT FROM AUTHOR]

This paper establishes an intelligent big data storage system IHDFS, based on the existing open source distributed file storage system HDFS. The system proposes and implements big data de-duplication module, big data placement module, big data intelligent migration module, and big data encoding module, which improves the efficiency of user visits and saves the storage space of the cluster. Experimental results show that the data de-duplication module can save the storage space. The data placement module provides a reasonable distribution of file upload storage layer, which twice the uploading speed; the data intelligent migration module improves the hit rate of files on the upper storage layer, which improves the efficiency of obtaining data; the data encoding module saves the storage space of the cluster about one third of the original. [ABSTRACT FROM AUTHOR]

Aiming at the problems of the poor quality of the hole shape formed by the transplanter will cause the seeding to tilt, when watermelon seedlings raised on pie-shaped compression substrate for transplanting. Opener parameters of hole-forming device in semi-automatic transplanter for watermelon seedlings raised on compression substrate is optimized to meet the agronomic requirements of transplanting compression substrate watermelon seedling and combining the characteristics of dryland transplanting machinery. Through analyzing the movement mechanism of the opener, this paper established the parameter equation of the planting hole. It was concluded that the depth of the hole-forming was the main factor affecting the longitudinal length of the upper part of the hole mouth. The Edinburgh Elasto-Plastic Cohesion Model, which can reflect the elastoplasticity and cohesiveness of soil. The simulation analysis of the hole-forming process of the opener was carried out by using the discrete element method. The rationality of the structure parameters and motion parameters of the opener was verified, and the hole-forming effect of different diameters of the small end of opener was explored at different theoretical depth of hole-forming. According to the simulation results, the diameter of the small end of opener was 60 mm and the theoretical depth of hole-forming was 65 mm. The bottom of the hole was relatively flat, effective depth of hole-forming was 51 mm. The upper longitudinal length of hole and the upper width of hole were relatively small. It was conducive to the growth of coated transplanted crops. In order to verify the accuracy of the above design method and the reliability of the operation of the hole-forming device, a prototype and 3 sets of opener with different small end diameters were trial-manufactured to carry out field experiments, and the upper longitudinal length of hole, upper width of hole and effective depth of hole-forming were measured. The results of the experiment combined with the simulation analysis showed that the upper longitudinal length of hole and the upper width of hole were increased with the increase of the theoretical depth of hole-forming. The upper longitudinal length of hole and the upper width of hole increased with the increase of the diameter of the small end of the opener. The influence of the diameter change of the small end of the opener on the upper longitudinal length of hole was weaker than the change of theoretical depth of hole-forming. The theoretical depth of hole-forming had a significant effect on the upper longitudinal length of hole. The larger the diameter of the small end of the opener, the more the upper width of hole increased as the theoretical depth of hole-forming. The minimum error between simulation result and the test result of upper longitudinal length of hole was 0.34%, the maximum was 12.78%, and the average error was 6.7%. The minimum error between the simulation result and test result of the upper width of hole was 7.23%, maximum was 20.87%, and average error was 12.33%. The minimum error between effective depth of hole-forming simulation results and test results was 1.79%, the maximum was 17.92%, and the average error was 10.46%. The research can provide a reference for the optimization and improvement of the opener. [ABSTRACT FROM AUTHOR]

The lunar surface topography mapping is the basic work of the lunar exploration and plays an important role in the three-phase (“around-fall-back”) lunar exploration program. In the “around” phase, it is necessary to use the camera carried by the spacecraft to acquire high-resolution image of area around the drop-off point. Due to the low orbit altitude and the limited field of view of camera, the width of the imagery obtained by the lunar satellite is relatively small compared to the range of the required drop-off area. Multiple strips stitching is an effective and practical way to solve large regional imaging problem. In a given multiple strips stitching task planning, it is required to optimize the sideswing angle of each orbit within a given mission duration to meet the regional coverage demand. To meet the requirements of region multiple strip stitched imaging task,an lateral swing optimization of method is proposed in this paper. Firstly, a fast algorithm based on vector polygon logical operation is proposed. Coverage polygons of each imaging strip are calculated based on the lateral swing angle, satellite orbit and the field of view of the sensor, then the coverage ratio can he computed via a Boolean operation between target polygon and strip coverage polygons. The proposed method of coverage ratio calculation can not only ensure the accuracy of calculation, hut also can dramatically reduce its computation complexity. Secondly, a lateral swing angle optimization model for multiple strip stitching imaging task is introduced, which uses swing angle as decision valuables, coverage ration maxi-mization as objective function respectively , and an improved adaptive genetic algorithm based on sigmoid function is proposed to solve the optimization model. Finally, two simulation experiments are executed to validate the validity of proposed method. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Computational Mechanics / Jisuan Lixue Xuebao is the property of Chinese Journal of Computational Mechanics Editorial Office, Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Harbin University of Science & Technology is the property of Journal of Harbin University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Natural Gas & Oil is the property of Editorial Department of Natural Gas & Oil and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Astragalus smicus, also known as Chinese milk vetch, Zi yunying and so on, is one of the main winter green manure crops in paddy fields of central and southern China, it has the advantages of reducing fertilizer input, improving soil fertility, increasing crop yield and quality, and protecting ecological environment, and has strong nitrogen fixation ability and high utilization efficiency. In recent years, the production machinery of Astragalus smicus has been developed and applied rapidly in terms of capacity and utilization efficiency, but its development still lags behind. Ditching and sowing are important links in the production of Astragalus smicus. The yield of Astragalus smicus is largely determined by the quality of sowing, and ditching operation can make Astragalus smicus grow well in low-humid field with poor drainage or sandy soil with poor fertilizer and water retention. Astragalus smicus is often used as green manure in paddy field, but high stubble retention, large amount of straw, insufficient in sowing height of existing other sowing equipments, working parts easily clogged, etc., bring difficulties for mechanized production of Astragalus smicus. In order to solve the influence of machine-harvested rice stubble on mechanized production of Astragalus smicus, aiming at the problems of low quality and low production efficiency in independent ditching and sowing links at present, a Astragalus smicus ditching and sowing machine which suitable for machine-harvested rice stubble field was developed. A height adjustable sowing device was designed, by which the sowing components could be lifted to a proper position according to the residual straw situation in the field. The special seed-metering wheel and quantitative evenly-sowed device for Astragalus smicus were developed to achieve precision sowing and improve the sowing uniformity. The structure and working parameters of the double-disk ditching components were determined. The variation coefficients of ditching width and depth determined by field experiments were less than 6%, which met the drainage requirements of Astragalus smicus growth process. The multiple factor experiments and regression analysis of the test data were carried out by Design-expert software, the results showed that forward speed of machine, rotation speed of seed-metering wheel, seed-uniforming cylinder diameter significantly affected the sowing performance, the results of variance analysis showed that the rotation speed of seed-metering wheel had the greatest influence on the emergence rate and coefficient of variation of sowing uniformity, while the forward speed of machine had the least influence on the emergence rate and coefficient of variation of seed-metering quantity consistency, regarding the coefficient of variation of sowing uniformity, the most influential factor was seed-uniforming cylinder diameter, and the minimum impact factor was the rotation speed of seed-metering wheel, the optimal factor parameters combination which affected the sowing quality of Astragalus smicus ditching and sowing machine was as follows: forward speed of machine was 4.6 km/h, rotation speed of seed-metering wheel was 44 r/min, seed-uniforming cylinder diameter was 6 mm. Verified by field experiments, the Astragalus smicus emergence rate was 95.87%, quantity consistency was 12.7%, coefficient of variation of sowing uniformity was 8.07% in the condition of optimal parameter combination, the relative error was below 3% compared with optimal values predicted by the model. Compared with the existing sowing methods of Astragalus smicus, working efficiency of the designed ditching and sowing machine was 1 hm2/h, which was superior to the artificial sowding working efficiency of 0.1 to 0.125 hm2/h, the hand-shaking working efficiency of 0.2 to 0.3 hm2/h and the motorized sowing working efficiency of 0.5 to 0. 8 hm2/h, and was lower than the UAV sowing working efficiency of 3 to 4 hm2/h. In addition, the coefficient of variation of sowing uniformity and the combination type of ditching and sowing machine were also significantly superior to that of other methods. The Astragalus smicus ditching and sowing machine developed in the paper integrated ditching and sowing links in one operation, the working efficiency was greatly improved, the research provided a new method for Astragalus smicus ditching and sowing machine for machine-harvested rice stubble field. [ABSTRACT FROM AUTHOR]

Laying duck raising and duck egg processing belong to traditional superior animal husbandry in China. Dirty surface of duck eggs will shorten storage time and increase subsequent cleaning cost. The bottom wire mesh is an important part of the furnished cage and is closely related to duck egg cleanliness. Aiming to solve the problem that the surface of duck egg shell is seriously polluted during the process of raising laying duck in the cascading cage-rearing equipment, the authors optimized the dimension parameters of the bottom wire mesh in this paper. Based on the analysis of duck egg movement on the bottom wire mesh, a kinematics simulation mode was developed to determine the appropriate range of the bottom wire mesh slope using dichotomy depending on whether duck eggs roll out of the furnished cage. The steeper the slope, the easier it was for the duck eggs to roll onto the conveyor belt. But if the slope was too large, the duck eggs might collide with the egg on the conveyor belt to cause damage. Meeting the above conditions, the appropriate slope value was chosen. According to the longitudinal spacing in bottom wire mesh, the lateral spacing in bottom wire mesh, the diameter in bottom wire mesh, the total deformation maximum and the mass of the bottom wire mesh, mathematical optimization model of the bottom wire mesh was established. The authors adopted an analysis method of 3 factors and 4 levels corresponding surface, and the dimension parameters of the bottom wire mesh were optimized based on the total deformation maximum response surface. The optimum solution in the results had the maximum area of the leakage hole in the bottom wire mesh. The finite element software ANSYS Workbench was used as the computing platform in this analysis. After optimization, the slope increased to 8.5°, the area of the leakage hole increased by 29.2%, and the total deformation maximum decreased by 18.1%. The area of the leakage hole bears on the cleanliness of the duck egg, the larger the area, the cleaner they were. This was because that duck dropping passed through the hole and fell onto the manure without sticking to the bottom wire mesh to soil the duck egg. Smaller deformation meant better structural stability. To test the feasibility of the optimization result, this research team experimented on cage-rearing laying duck using the bottom wire mesh optimized in a welfare duck farm of Hubei Shendan Healthy Food Company. The experiment included 384 ducks weighting in (1 350±50) g and lasted for a whole month. Ducks were divided into test group and control group living in the same environment. 2 ducks were raised in every cage. The results showed that the bottom wire mesh had a significant positive effect on duck egg cleanliness (P<0.01), and the average cleanliness of duck egg in the test group was 1.21 which was lower than 2.01 in the control group. It’s known that cleanliness had negative correlation with effect. Before and after optimization, the bottom wire mesh had no significant effect on duck feather damage, laying rate and duck egg breakage rate. During the experiment, there was no obvious mass duck leg injuries in the experimental group, and the rate of death and elimination were in a reasonable interval in comparison with the average in the farm. This study solved the problem that the surface of duck egg shell was seriously polluted, and has high practical value. Meanwhile, this research method can provide reference for the development of furnished cage wire for poultry cage-rearing equipment. [ABSTRACT FROM AUTHOR]

For transplanting vegetables plug seedlings, it is difficult to directly pick up seedlings from the tray cells. Damages of root lumps of plug seedling happen all the time in extracting. In this paper, a root lump loosening mechanism using air jets to eject vegetable plug seedlings making for transplanting was designed and evaluated. It consisted of air jets, a linear module, a double-rod cylinder, a control system and some other supporting parts. The step transmission of the air jet along the horizontal direction was performed using the linear module, which was a synchronous belt system. The air jet′ motion along the vertical direction up and down for ejecting plug seedlings was moved by the double-rod cylinder. For high blowing rates, wholes rows of air jets aiming for each drain hole was designed. In this arrangement, the seedlings could be loosened row by row. With a row of air jets blowing the seedling plugs from the drain holes of the tray cells, air pressures along with the force of the plungers effectively loosened seedlings. It would be good for manual pulling seedlings or automatically picking up seedlings from the tray cells. Based on the integrated design and analysis, the air pressure range of succeeding in loosening seedling plugs was 0.098-0.235 MPa using the air jet at the diameter of 5 mm. Under this condition, the seedlings appeared to be most effective in the loosening and not in destroy of the root soil. Meanwhile, the air jet could eject each drain hole at the bottom of the 128-cell tray. Being the first prototype, its optimal machine parameters were examined under various conditions. In the optimum tests, it was found that the air pressure of the air jet plungers exerted the greatest effect on the integrated ratio in loosening seedling plugs, and followed by the moisture content. Other factors such as the seedling age, the air flow rate and the air jet with sponges or not had no significant effects on the integrated ratio in loosening seedling plugs. In reality, it would probably be a moderate air blast for blowing of the plug seedlings from the tray. If the moisture content of root lumps of the plug seedlings was less than 55%, the cohesion forces between the roots and the tray cell walls would increase. In this case, wetting the roots might serve to reduce the adhesion making for blowing. For cucumbers seedlings, when the air pressure of the air jet plungers was 0.2 MPa, the root zone moisture was 55%-60%, the seedling age was 25 d, the airflow circuit was fully open at the outlet of 4 mm, and the air jet had no sponges, the best intact rate succeeding in loosening root lumps of plug seedlings was achieved. Finally, the overall loosening performance test was carried out. The intact rate of seedling and root lump in loosening root lumps by blowing was more than 96%. It needed about 48 s for finishing loosening the whole tray of plug seedling. The loosening mechanism using air jets to eject vegetable plug seedlings has a good performance, which can meet the actual requirements. [ABSTRACT FROM AUTHOR]

The widely use of plastic film mulching technology in agriculture increase crop yields and farmers' income. However, with the extensive use of plastic film, the residual film in the soil is also accumulating yearly, and the accumulated residual film is hard to be removed from soil. If the residual film in soil plough layer can-not be timely treated, it will lead to soil fertility decline, resulting in crop yield reduction and soil contamination. Therefore, it is an urgent issue to remove the residual film from soil, especially in the tillage layer. In order to solve the problem of remnant film recovery, according to the characteristics of the remnant film recovery machine, and according to the requirements of the agronomy of plastic film recovery, a chain-tooth residual film recovery machine is designed and manufactured. It is expected that the transport of membrane-soil, reverse separation of membrane-soil and membrane-collecting process can be completed. In this paper, we studied the influence of the parameters of the reverse membrane-soil separator of the chain-tooth residual membrane recovery machine on the separating effect of the membrane-soil. By analyzing the influence of the parameters on the performance of the reverse membrane-soil separator of the chain-tooth residual membrane recovery machine, the optimal working parameters were obtained, which could provide reference for the follow-up study and optimization of the membrane-soil separator. Aiming at the problems of poor mechanical properties of residual film deposited in the soil plough layer for many years, difficult separation of membrane and soil, and low recovery rate of residual film debris, a chain-tooth residual film recovery machine was designed. The main working parts of the machine are picking up device and membrane soil separating device. The working depth of the machine is 0-150 mm. The pickup device completes the membrane pickup and conveys the soil with the plastic membrane. Then the residual membrane is separated by the reverse membrane soil separating device, and finally the residual membrane is transported to the membrane collector. Taking angular velocity of pickup device, angular velocity of membrane-soil separator and angle of membrane-soil separator as experimental factors, quadratic regression orthogonal test of three factors and three levels was carried out in this study on chain-tooth residual membrane recovery machine with response values of residual membrane recovery rate and soil content. The response surface model of each factor was obtained by experiment, and the influence of each factor on the operation effect was analyzed and optimized. The results showed that the order of the factors affecting the recovery of residual membrane was: angle of membrane-soil separator > angular velocity of pickup device > angular velocity of membrane-soil separator. The order of the factors affecting the soil content was: angle of membrane-soil separator > angular velocity of membrane-soil separator > angular velocity of pickup device; and the optimized results were tested. The results showed that the recovery rate of residual membrane was 81.12% and the soil content was 34.83% when the angular velocity of the pickup device was 42 rad/s, the angular velocity of the membrane-soil separator was 57 rad/s and the angle of the membrane-soil separator was 37°, and the relative error between the experimental value of each evaluation index and the optimized value of the model was less than 5%. The reverse membrane-soil separator can solve the problems of difficult membrane-soil separation and low recovery rate of residual membrane fragments. It can provide a reference for further research and optimization of membrane-soil separator mechanism of residual membrane recovery machine. [ABSTRACT FROM AUTHOR]

In order to improve the flow field structure of the air distribution chamber of the drying box for fruit and vegetable, improving the uniformity of airflow distribution. In this paper, the Fluent software was used to simulate the flow field characteristics and the outlet air velocity of the original air distribution chamber in the hot air drying box of fruit and vegetable. According to the simulation,4 optimization methods were put forward for the structure of the original air distribution chamber. Then the improved structure was simulated.and the simulation results compared with the flow field characteristics and velocity distribution of the original structure, at the same time. The speed deviation ratio E and speed non-uniformity coefficient M were introduced to evaluate the uniformity of various structural speeds. Finally. the structure of air distribution chamber in the hot air drying box was obtained under the design condition. [ABSTRACT FROM AUTHOR]

The equivalence connection between tables in the statistical analysis of data is one of the commonly used operations,but the price is relatively high. In big data environment,the connection of large scale data tables is less efficient. In order to solve this problem,this paper proposed a method for optimization of two-table equivalent connection process based on Spark. First,it constructed the Bloom filter to complete the filtering operation according to the low density of data density.Secondly,it combined the advantages of simi-join method and partition join methods,and used the greedy algorithm splitting methods for the filtered unilateral table. Lastly,it joined the split subsets,so it changed the connection process of two big tables into two stages of the two small table connection. Cost analysis and experiments show that the proposed algorithm improve performance compared with the existing Spark-based connection operation performance and data tilt. [ABSTRACT FROM AUTHOR]

In order to identify the emotion types in speech signals, this paper proposed an improved genetic algorithm optimized BP neural network(IAGA-BP). This algorithm enhanced the optimization performance of genetic algorithm by improving the selection operator and the adaptive crossover and mutation probability formula, such that optimizing the initial weights and thresholds of the BP neural network. The experimental results show that the IAGA-BP network can effectively improve the recognition rate and speed up the convergence compared with the BP, GA-BP and AGA-BP networks. [ABSTRACT FROM AUTHOR]

The double vane pump is a special type of flow vane centrifugal pump. It adopts a design with less blades, which leads to a disadvantage that the performance of the double vane pump is inferior to that of the multi-blade pump at the same specific velocity. Its stability is 3%-8% lower than of a vane centrifugal pump.Therefore, it is necessary to improve the work efficiency by optimizing the hydraulic design. This article took a double-passage sewage pump model 80QW50-15-4 as the research object. The optimization objective was to design the head and efficiency of the flow point. ANSYS CFX(computational fluid dynamics x) was used to perform numerical simulation to obtain performance data. According to the two-dimensional hydraulic drawing of the initial model pump, the three-dimensional modeling software Pro/Engineer5.0 was used to simulate the water body of the impeller and the volute and to perform mesh division and irrelevance verification. The model pump was subjected to numerical simulation and experiment of clear water medium, and the performance curve was obtained and compared. The error analysis showed that the maximum error of head and efficiency was 3.9% and 1.7%, which meant that the performance prediction model established by this method had high accuracy. Partial initial model impeller structure parameters were selected for performance impact analysis. The Plackett-Burman screening test was used to determine the blade wrap angle, blade outlet angle and impeller outlet width were significant factors affecting head and efficiency of design flow. According to Fang Kaitai's unified design table, training samples of RBF(radial basis function) neural network were arranged, so as to establish important structural parameters and performance prediction models, and generated 5 groups of structural parameters random for neural network testing and error analysis. The head and efficiency performance prediction model trained by radial basis neural network was introduced into the particle swarm optimization algorithm as the fitness evaluation model of particle swarm optimization algorithm. The Pareto optimal solution set of head and efficiency was obtained, and the optimal head and efficiency were selected. In addition, this paper also studied the performance and internal flow field differences of the initial individual, the optimal individual of head and the optimal individual of efficiency when transporting different media. It was known from the performance curve that the performance of individuals was improved when transporting different media. The reason for the performance improvement was revealed by the internal flow field distribution map. In order to verify the practicability of the optimization results, a clear water test was performed on the optimal head and the most efficient individual to obtain a performance curve and compared with the performance curve of the initial individual. Among them, the experimental head of the optimal head at the design flow point increased by 0.96 m than the initial individual, the increase rate reached 5.5%, the efficiency increased by 1.6 percentage point; the efficiency of the best individual increased by 10.11 percentage point, the head decreased slightly but met the design requirements. The test proved that the optimization effect was obvious. This optimization method improves the hydraulic characteristics of impeller and the performance of double vane pump. [ABSTRACT FROM AUTHOR]

Under the condition of randomness of weight threshold, the existing availability modeling of multi-state systems has limitations in practice. In this paper, quantity threshold and randomness of the weight threshold are both considered, and a new method of combining stochastic joint operator with general generation function is proposed to solve the problem that the quantity and weight of the components in the k/N systems cannot be mapped to each other. Thus, the mission-availability evaluation model of the system is obtained, which is applicable to the case where the weight threshold is subject to continuous random distribution, and which is superior to the traditional recursive algorithm. Then, two system optimization models under system availability constraint or system cost constraint are constructed respectively, and the genetic algorithm programming is applied to achieve the optimal component's probabilities and weights. Finally, the ship transportation is taken as an example to illustrate the effect of the quantity threshold on system mission-availability and the optimization results under the random weight threshold are given. The research results can be useful for solutions and methods for system engineers to carry out reliability design and improvement. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Energy saving and consumption reduction have been important measures of enterprise development. Considering the periodic user load and the peak valley tariff policy, an optimization model of economic operation for LNG receiving terminal is established, from which an analytic formula (optimization criterion) for the optimization policies of economic operation is derived. Due to the complex operating conditions and the coupled devices in which the operating conditions are affected each other, it is difficult to get the solution of the model analytically, therefore a dynamic simulation system for the LNG receiving terminal system with the accurate dynamic characteristics of the terminal and the optimization criterion derived is built here, with which a case study of a domestic LNG receiving terminal under operation is made. The results of the case study affirm the effectiveness of this optimization criterion and the reliability and superiority of the dynamic simulation platform in the optimization process. In this paper, the operation strategy of three typical user load conditions of the receiving terminal is researched. About 4. 38 percent of the electricity bill may be saved monthly for the LNG receiving terminal under this strategy. [ABSTRACT FROM AUTHOR]

The perpendicularity is an important index for evaluating the quality of pot seedling transplanting. At present, the planting mechanism easily resulted in lower tilt and lower perpendicularity of seedling, which leads to lower survival rate of the seedling in the bowl. In order to solve this problem, according to the agronomic requirements of pot seedling planting and based on the physical characteristics of pot seedling, the design requirements of planting mechanism were put forward in this paper, and a planetary gear-train slid way planting mechanism was designed. Through the cooperation of the planetary gear train and the slide track, the pot seedling planting in the bowl was accomplished by the way of shooting seeding, and the operation process of the mechanism was analyzed, and the kinematics model of the mechanism was established. Based on MATLAB, the optimization software of auxiliary analysis of planting mechanism was compiled, and the planting track and structural parameters of the mechanism were optimized, and a group of optimal structural parameters that meet the requirements of seedling planting was obtained, that means, the radius of solar wheel R0= 20 mm, the radius of middle wheel R1= 15 mm, the radius of planetary wheel R2=10 mm, the length of connecting rod(BC) L1= 100 mm, the length of rod CD on planting arm L2= 150 mm, the length of rod CF on planting arm L3= 80 mm, the length of duck bill planter(FG) L4= 140 mm, the distance from point E to origin of coordinate O on a slide DE L5= 100 mm, the angle of initial installation of planetary frame(OB) α0= 45°, the angle between connecting rod BC and X axis α1= 45°, the angle between rod DC and rod CF of planting arm β=176°, and the angle between slide DE and X axis θ=108°. In this combination, the structure design and 3D virtual assembly of the planting mechanism were completed, and the virtual movement and simulation analysis of the mechanism were carried out in ADAMS, and the rationality and accuracy of the mechanism design were verified. According to the optimized parameters, the physical prototype was produced, and the field experiment was carried out with the vertical degree of the bowl seedling as the main test index. The field test results showed that when the speed of the planter was 450 mm per second and the planting frequency was 74 plants per minute, the transplanting perpendicularity was high, and the qualified rate was 94%, which meets the requirements of planting performance. The results can provide references for designingplanting mechanism of potted seedling transplanting machine. [ABSTRACT FROM AUTHOR]

In recent years, with the rapid development of agricultural mechanization in China, rice transplanter has been widely used. Because the transplanting parts of the transplanter have a large vibration in the working process, it will have a great impact on the operation of the machine and the operating environment of the driver. At present, the analysis of the vibration of the support arm of the transplanter and the research on how to reduce the vibration and noise are still in initial stage. In the working process, the support arm bears a variety of dynamic loads, including the working load of various parts, engine and road surface stimulation. When the frequency of the dynamic load is close to the natural frequency of the support arm, the resonance phenomenon will occur. The mechanical resonance affects the normal operation of the transplanter, reduces the service life of the transplater, and seriously affects the comfort of the working environment. Therefore, it is of great of significance to study the vibration and noise reduction of rice transplanter. In view of the vibration and noise problems in the power transmission process of high-speed rice transplanter planting mechanism, 2ZG-6DK rice transplanter was taken as the research object in this paper, and the power transmission mode and working principle of planting system were analyzed. The 3D software was used to standardize the support arm which is the key components in the power transmission system of the transplanter, and the model was imported into the ANSYS Workbench and combined with the Lanczos Method to solve the modal natural frequency and mode shape. In order to optimize the structure of the support arm based on the finite element model, it is necessary to verify the accuracy of the finite element model of the support arm. The modal test of the supporting arm of Nantong 2ZG-6DK transplanter was carried out by using DH5902 Dynamic Data acquisition and modal analysis system, the first 4-order modal frequency and mode of the support arm of the transplanter were obtained by signal analysis and parameter identification. The accuracy of the finite element model of the support arm was verified by the comparison between the modal test results and the finite element analysis results. Based on this, MAC-based (modal assurance) was carried out and the accuracy of finite element analysis was verified. The criterion test optimized the modal test to verify the accuracy of the finite element theory analysis. In order to avoid the external excitation frequency of the support arm, based on the analysis of the external frequency excitation characteristics, and on account of the ISIGHT multidisciplinary software platform, the structural parameters of the support arm were optimized by the sequential quadratic programming method. The results showed that the thickness of the optimized support arm sidewall cavity was 5.7 mm, the beam width was 42.0 mm, the arm length was 497.0 mm, and the first 4–order modal frequencies were adjusted to 135.17, 204.23, 483.14 and 702.32 Hz respectively, which all avoided the gasser engine excitation frequency range 86.67~120 Hz. After the optimization, the vibration amplitude attenuation was the most obvious at the 1-order frequency, the vibration amplitude was decreased by 9.4%, and the low-frequency vibration characteristics of the support arm were significantly improved. The research results can provide reference for the vibration characteristics analysis and vibration reduction design of the rice transplanter. [ABSTRACT FROM AUTHOR]

Well pattern optimization and deployment of coalbed methane(CBM) are the important part to the development scheme of CBM.A reasonable well pattern can dramatically increase the CBM production as well as reduce the development costs.For this problem,based on the Qinnan-East block in the Qinshui basin, this paper systematically analyzed coal seam conditions and distribution characteristics of gas contents and permeability in study area. By calculating the production dynamics of different well pattern schemes on the basis of numerical simulation,an optimization method for determining reasonable well spacing is put forward by synthetically considering the economic evaluation parameters including cumulative cash flow and recovery rate. It is shown that the thickness of No.3 coal seam in Shanxi formation varies from 4 to 6 m with average of 5.61 m, and burial depth varies between 417.93 and 1 527.49 m.Gascontents of No.3 coal seam vary from 2.87 to 24.63 m3/t with average of 13.78 m3/t and increase with burial depth by the law of logarithmic function.Well test permeability of target coal seam is lower, which vary from 0.01×10-15 to 0.2×10-15 m2 with average of 0.06×10-15 m2 and decrease with burial depth by exponential function law.According to the coal reservoir conditions in study area,CBM production with well spacing of different burial depths well pattern was calculated on the basis of numerical simulation as well as determined the reasonable well spacing of different burial depths by synthetically considering cumulative cash flow and recovery rate. It is analyzed that well spacing in study area is 350 m×300 m for the burial depth shallower than 500 m,350 m×250 m for the burial depth between 500 m and100 0 m and 250 m×200 m for the burial depth deeper than 1 000 m.But the actual well pattern deployment should be adjusted according to the actual geological conditions. These understandings provide a theoretical basis for the reasonable formulation of well pattern in the CBM development in this area. [ABSTRACT FROM AUTHOR]