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System dynamics model of the support-surrounding rock system in fully mechanized mining with large mining height face and its application

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International Journal of Mining Science and Technology 2013年第6期23卷 879-884页

作者： Yuan Yong Tu Shihao Zhang Xiaogang Li Bo School of Mines China University of Mining&Technology Key Laboratory of Deep Coal Resource Mining Ministry of Education China University of Mining&Technology

Fully mechanized mining with large mining height(FMMLMH)is widely used in thick coal seam mining face for its higher recovery ratio,especially where the thickness is less than 7.0 ***,because of the great mining height and intense rock pressure,the coal wall rib spalling,roof falling and the instability of support occur more likely in FMMLMH working face,and the above three types of disasters interact with each other with complicated *** order to get the relationship between each two of coal wall,roof,floor and support,and reduce the occurrence probability of the three types of disasters,we established the system dynamics(SD)model of the support-surrounding rock system which is composed of"coal wall-roof-floor-support"(CW-R-F-S)in a FMMLMH working face based on the condition of No.15104 working face in Sijiazhuang coal *** the software of Vensim,we also simulated the interaction process between each two factors of roof,floor,coal wall and the *** results show that the SD model of"CW-R-F-S"system can reveal the complicated and interactive relationship clearly between the support and surrounding rock in the FMMLMH working *** increasing the advancing speed of working face,the support resistance or the length of support guard,or by decreasing the tipto-face distance,the stability of"CW-R-F-S"system will be higher and the happening probability of the disasters such as coal wall rib spalling,roof falling or the instability of support will be *** research findings have been testified in field application in No.15104 working face,which can provide a new approach for researching the interaction relationship of support and surrounding rock.

关键词： FMMLMH Support-surrounding rock system SD model Disaster control simulation analysis

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Characteristic analysis of Off-Axis Meta-Lens

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Optics and Photonics Journal 2023年第6期13卷 87-96页

作者： Jingaowa Hu Yang Liu Shangnan Zhao Lingjie Wang Haokun Ye Jianping Zhang Xin Zhang Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun China University of Chinese Academy of Sciences Beijing China

Meta-lens are a new type of planar optical element that can flexibly manipulate the phase, polarization and amplitude of the beam, and are currently receiving a great deal of attention as they are easier to process and manufacture. Off-axis meta-lens are a special type of meta-lens with a certain degree of dispersion that can be used as a beam-splitting element, providing a unique and feasible way to realize micro-miniature instruments. We analyze the effects of different numerical apertures and off-axis angles on the spectral resolution, focusing efficiency and simulation results of off-axis meta-lens to provide ideas for subsequent research and application of off-axis meta-lens. A number of off-axis meta-lens with parameters NA = 0.408 α = 13°, NA = 0.18 α = 13° and NA = 0.408 α = 20° were simulated through Lumerical software. The results show that the off-axis angle is related to the resolution;the larger the angle, the better the spectral resolution but the lower the focusing efficiency;when the numerical aperture is smaller, the smaller the coverage of the phase distribution, which will lead to a larger deviation between simulation and theory. The designer needs to balance the numerical aperture, off-axis angle and other parameters reasonably according to the requirements in order to achieve the desired effect. The findings of this study have important reference values for the theoretical analysis of off-axis meta-lens and the design of parameters in practical applications. .

关键词： Meta-Lens Off-Axis Meta-Lens simulation analysis

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Control algorithm and energy management strategy for extended range electric tractors

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International Journal of Agricultural and Biological Engineering 2017年第5期10卷 35-44页

作者： Xu Liyou Zhang Junjiang Liu Mengnan Zhou Zhili Liu Chengqiang College of Vehicle and Traffic Engineering Henan University of Science and TechnologyLuoyang 471003China Shandong Shifeng Group Co. Ltd.Liaocheng 252800China

It is difficult to make full use of the electrical energy of the power battery for extended-range electric tractors because the battery’s state of charge may be relatively high at the end of the running *** address this situation,this paper aimed to study the control parameter adjustment in relation to the power battery’s electrical consumption and the diesel engine’s fuel consumption energy management *** on the AVL-Cruise simulation platform,the vehicle model of the tractor was established,and the control module of AVL-Cruise was used to compile the energy management *** order to verify the superiority of the proposed strategy,the contrast strategy was employed in terms of the diesel engine start and stop control plus fixed point energy management strategy(FPEMS).The applicability of the proposed strategy was tested through continuous transfer operation and the small area deep loosening *** simulation results show that the proposed strategy was of good *** with the FPEMS,the fuel consumption reduced significantly,and the electrical consumption of the power battery increased obviously.

关键词： extended-range electric tractor parameter adjustment energy management strategy simulation analysis

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Design and experiment of vertical pneumatic fertilization system with spiral Geneva mechanism

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International Journal of Agricultural and Biological Engineering 2021年第4期14卷 135-144页

作者： Haibo Chen Jingfu Zheng Shaojie Lu Shan Zeng Silong Wei Experimental Basis and Practical Training Center South China Agricultural UniversityGuangzhou 510642China College of Engineering South China Agricultural UniversityGuangzhou 510642China

In the traditional fertilization method,a large amount of fertilizer is applied,which causes congestion *** is not conducive to the sustainable development of *** this work,a vertical pneumatic fertilization system with a spiral Geneva mechanism was designed according to the operational requirements of variable-rate and smooth *** uniformity in discharging fertilizer with different spiral angles was simulated and analyzed by extended discrete element method(EDEM)based simulation software,from where the spiral angle of the fertilizer discharge wheel was determined to be 45°.The fertilization system includes a fertilizer apparatus with a spiral Geneva mechanism,whose optimal performance parameters were obtained from the bench *** accuracy and uniformity of the fertilizer application system were taken as the evaluation *** linear relationships of the discharged amount of fertilizer with the rotational speed and the opening of the fertilizer discharging wheel were verified by both static blowing fertilization and field *** static blowing experimental results show that the discharged amount of fertilizer has a high linear correlation and accuracy with both the opening and rotational speed,and the highest correlation occurs with the rotational *** rotational speed and opening have significant effects on the discharged amount of fertilizer and the average coefficient of *** effect of the rotational speed was the most *** to the model obtained by multiple regression fittings,the optimal parameters were determined when the average coefficient of variation was small,the rotational speed was 15.9 r/min and the opening was 34.4 ***,the purpose of precise fertilization can be achieved by adjusting the opening or rotational speed in a way to get the exact amount of fertilizer discharged as required by the corresponding *** field experiment showed that the variation co

关键词： precision fertilization fertilizer apparatus variable rate technology spiral Geneva mechanism simulation analysis performance experiment

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Design and simulation of an integrated end-effector for picking kiwifruit by robot

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Information Processing in Agriculture 2020年第1期7卷 58-71页

作者： Longtao Mu Gongpei Cui Yadong Liu Yongjie Cui Longsheng Fu Yoshinori Gejima College of Mechanical and Electronic Engineering Northwest A&F UniversityYanglingShaanxi 712100China China Aviation Lithium Battery Research Institute Co. LtdChangzhouJiangsu 213200China Key Laboratory of Agricultural Internet of Things Ministry of Agriculture and Rural AffairsYanglingShaanxi 712100China Shaanxi Key Laboratory of Agricultural Information Perception and Intelligent Service YanglingShaanxi 712100China Faculty of Agriculture University of MiyazakiMiyazaki 8892192Japan

The harvesting of fresh kiwifruit is a labor-intensive operation that accounts for more than 25%of annual production *** harvesting technologies are thus being developed to reduce labor requirements for harvesting *** improve the efficiency of a harvesting robot for picking kiwifruit,we designed an end-effector,which we report herein along with the results of tests to verify its *** using the established method of automated picking discussed in the literature and which is based on the characteristics of kiwifruit,we propose an automated method to pick kiwifruit that consists of separating the fruit from its stem on the *** method is experimentally verified by using it to pick clustered kiwifruit in a scaffolding canopy *** the experiment,the end-effector approaches a fruit from below and then envelops and grabs it with two bionic *** fingers are then bent to separate the fruit from its *** grabbing,picking,and unloading processes are integrated,with automated picking and unloading performed using a connecting rod linkage following a trajectory *** trajectory was analyzed and validated by using a simulation implemented in the software Automatic Dynamic analysis of Mechanical Systems(ADAMS).In addition,a prototype of an end-effector was constructed,and its bionic fingers were equipped with fiber sensors to detect the best position for grabbing the kiwifruit and pressure sensors to ensure that the damage threshold was respected while *** for size and shape were incorporated by following a trajectory groove from grabbing and picking to *** end-effector separates clustered kiwifruit and automatically grabs individual *** takes on average 4–5 s to pick a single fruit,with a successful picking rate of 94.2%in an orchard test featuring 240 *** study shows the grabbing–picking–unloading robotic end-effector has significant potential to facilitate the harvesting of kiwif

关键词： Kiwifruit End-effector Harvesting robot Trajectory model simulation analysis

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Modeling and simulation of intersection quasi-moving block speed guidance based on connected vehicles

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Journal of Intelligent and Connected Vehicles 2020年第2期3卷 67-78页

作者： Qing Xu Jiangfeng Wang Botong Wang Xuedong Yan State Key Laboratory of Automotive Safety and Energy School of Vehicle and MobilityTsinghua UniversityBeijingChina Department of Traffic Engineer Beijing Jiaotong UniversityBeijingChina Department of ICV Testing and Research CATARC Automotive Test Center(Tianjin)Co.LtdTianJinChina

Purpose–This study aims to propose a speed guidance model of the CV environment to alleviate trafﬁc congestion at intersections and improve trafﬁc efﬁ*** introducing the theory of moving block section for high-speed train control,a speed guidance model based on the quasi-moving block speed guidance(QMBSG)is proposed to direct platoon including human-driven vehicles and connected vehicles(CV)through the intersection ***/methodology/approach–In this model,the green time of the intersection is divided into multiple block intervals according to the minimal safety *** vehicles can pass through the intersection by following the block interval using the QMBSG *** block interval is assigned dynamically according to the traveling relation of HV and CV,when entering the communication range of the *** validate the comprehensive guidance effect of the proposed model,a general evaluation function(GEF)is *** to CVs without speed guidance,the simulation results show that the GEF of QMBSG model has an obvious ***–Compared to CVs without speed guidance,the simulation results show that the GEF of QMBSG model has an obvious ***,compared to the single intersection speed guidance model,the GEF value of the QMBSG model improves over 17.1%.To further explore the guidance effect,the impact of sensitivity factors of the CVs’environment,such as intersection environment,communication range and penetration rate(PR)is *** the PR reaches 75.0%,the GEF value will change suddenly and the model guidance effect will be signiﬁcantly *** paper also analyzes the impact of the length of block interval under different PR and trafﬁc *** is found that the proposed model has a better guidance effect when the length of the block section is 2 s,which facilitates trafﬁc congestion alleviation of the intersection in ***/value–Based on the aforementioned discussion,the

关键词： simulation analysis Block interval Connected vehicle Quasi-moving block Speed guidance

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analysis of the Decadal and Interdecadal Variations of the East Asian Winter Monsoon as Simulated by 20 Coupled Models in IPCC AR4

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Acta meteorologica Sinica 2012年第4期26卷 476-488页

作者：贺圣平王会军 Nan-Zhu International Research Center Institute of Atmospheric PhysicsChinese Academyof Sciences Climate Change Research Center Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

Using the output data of 20 coupled climate models used in IPCC AR4 and observational data from NCEP, the capability of the models to simulate the boreal winter climatology of the East Asian sea level pressure, 850-hPa wind, and surface air temperature; the decadal variations of the East Asian winter mon- soon （EAWM） intensity and EAWM-related circulation, and the interdecadal variations of EAWM-related circulation are systematically evaluated. The results indicate that 16 models can weakly simulate the declin- ing trend of the EAWM in the 1980s. More than half of the models produce relatively reasonable decadal variations of the EAWM-related circulation and the interdecadal differences of EAWM-related circulation between the boreal winters of 1960-1985 and 1986-1998, including the weakened Siberian high, Aleutian low, and East Asian trough, the enhanced Arctic oscillation and North Pacific oscillation, and a deepened polar vortex. It is found that the performance of the multi-selected-model ensemble in reproducing the spatial dis- tribution of the variations is encouraging, although the variational amplitudes are generally smaller than the observations. In addition, it is found that BCCR-BCM2.0, CGCM3.1-T63, CNRM-CM3, CSIRO-MK3.0, GISS-ER, INM-CM3.0, and MRI-CGCM2.3.2 perform well in every aspect.

关键词： IPCC AR4 East Asian winter monsoon interdecadal variations simulation analysis

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Operation power consumption and verification tests of a trenching device for orchards in Xinjiang based on discrete element

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International Journal of Agricultural and Biological Engineering 2021年第1期14卷 133-141页

作者： Chen Ma Jiangtao Qi Za Kan Shaojie Chen Hewei Meng College of Mechanical and Electrical Engineering Shihezi UniversityShihezi 832000XinjiangChina College of Mechanical and Electronic Engineering Xinjiang Vocational UniversityUrumqi 830013China Key Laboratory of Northwest Agricultural Machinery of the Ministry of Agriculture Shihezi 832000XinjiangChina Ruiyida Machinery Equipment Co. Ltd.Shihezi Development ZoneShihezi 832000XinjiangChina

According to the agronomic requirements of orchard planting pattern and fertilization in Xinjiang,the soil particle models and a soil-trenching device interaction model were established by using discrete element simulation software in order to find out the law of influence of structure parameters and working parameters on the operation power consumption of a segmented cutting trenching device;moreover,its cutting process was simulated according to the response surface test *** to the results of research on the influence of forward speed,cutter disk speed and cutter disk combination on the operation power consumption of the segmented cutting trenching device,the law of their influence on the operation power consumption in descending order is forward speed,cutter disk combination,cutter disk *** to the response surface test result,the following influential factor parameter combination has been obtained:forward speed 815 m/h,cutter disk speed 112 r/min,cutter disk combination A(cut angle 150°,bent angle 60°and working width 133 mm),cutter disk combination B(cut angle 180°,bent angle 90°and working width 166 mm),and trenching operation power consumption-optimization results were verified through field *** to the verification,the results showed a high accuracy of the simulation,with a relative error mean of 3.18%between the theoretical value and the field test *** study can provide a reference for the energy-saving design of orchard trenching devices.

关键词： trenching device discrete element orchard power consumption simulation analysis parameter optimization

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Study on the Outdoor Wind Environment simulation and Design Strategies of Rural Settlements in Cold Areas

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Journal of Harbin Institute of Technology(New Series) 2014年第5期21卷 72-76页

作者： Ming Li Hong Jin Xin-Yu Zhang School of Architecture Harbin Institute of Technology

To improve the outdoor environment of rural settlement and reduce the energy consumption of rural houses in winterin cold areas,the seriously bad wind environment should been controlled and considered. This paper applies the method of numerical simulation to simulate the wind environment of some typical arrangement of building and courtyard in winter,and concludes the optimal building and courtyard arrangement types and strategies. It aims to provide some technical supports for improving the wind environment of rural settlements in cold regions.

关键词： rural settlements wind environment microclimate simulation analysis planning strategies

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基于仿真分析的随机活动工期鲁棒性项目调度优化

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管理科学 2023年第9期

作者：贾梦超何正文王能民

在不确定环境下，项目的计划与控制对项目能否顺利实施十分重要。考虑随机活动工期，研究了如何借助仿真分析确定鲁棒性调度优化的最佳项目输入参数组合。首先，对研究问题进行界定；随后，构建鲁棒性项目调度优化模型，并设计仿真分析... 详细信息

在不确定环境下，项目的计划与控制对项目能否顺利实施十分重要。考虑随机活动工期，研究了如何借助仿真分析确定鲁棒性调度优化的最佳项目输入参数组合。首先，对研究问题进行界定；随后，构建鲁棒性项目调度优化模型，并设计仿真分析流程，建立项目输入参数与仿真指标之间的对应关系；接着，开发了禁忌搜索启发式算法对鲁棒性调度优化模型进行求解，并制定了仿真实施流程；最后，通过一个实际案例对研究进行说明。得到结论：进度计划的鲁棒性随项目计划工期与资源可用量的增大而增大，达到一定值后保持稳定；当选取不同的仿真指标时，得到的最佳输入参数的组合不同，管理者可根据实际需求选取相应的指标。研究能够为不确定条件下鲁棒性项目调度提供指导，有助于项目进度计划鲁棒性的提升。

关键词：鲁棒性项目调度优化模型启发式算法仿真分析随机活动工期 robust project scheduling optimization model heuristic algorithm simulation analysis random activity duration

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