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China’s alfalfa market and imports: Development, trends, and potential impacts of the U.S.-China trade dispute and retaliations

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Journal of Integrative Agriculture 2020年第4期19卷 1149-1158页

作者： qingbin wang ZOU Yang Department of Community Development and Applied Economics University of VermontBurlingtonVT 05405USA School of Economics Nankai UniversityTianjin 300071P.R.China

This study examines the development and trends of China’s alfalfa market and imports, identifies key factors for the rapid increase in China’s alfalfa imports, and discusses potential impacts of the U.S.-China trade dispute and retaliations on the alfalfa markets and trade in both nations. China’s rapid transition toward larger-scale commercial dairy production, with enhanced feed and cost management as well as quality and safety control, and its limited resources for high-quality alfalfa production are key factors for the dramatic increase in its alfalfa imports, from 19 601 metric tons in 2008 to 1.38 million metric tons(mmt) in 2018. While the United States dominated China’s alfalfa imports with an average share of 97.01% from 2007 to 2017, the share dropped to 83.76% in 2018 and 63.28% in January 2019 due to the trade dispute and retaliations started in 2018. China will likely remain a large importer of alfalfa because of both its growing demand and the comparative advantages of imported alfalfa in quality and price, but the imports from the United States will be highly affected by the ongoing trade dispute and negotiations. China is also expected to make more efforts to reduce its dependence on U.S. alfalfa through increased investment in domestic alfalfa production and identification of alternative sources of alfalfa and other hay imports.

关键词： China’s alfalfa imports U.S.alfalfa exports dairy industrialization U.S.-China trade dispute and retaliations GM-free standards

Motion Control in Saccade and Smooth Pursuit for Bionic Eye Based on Three-dimensional Coordinates

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Journal of Bionic Engineering 2017年第2期14卷 336-347页

作者： qingbin wang Wei Zou De Xu Zheng Zhu Research Center of Precision Sensing and Control Institute of Automation Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100190 China

Saccade and smooth pursuit are two important functions of human eye. In order to enable bionic eye to imitate the two functions, a control method that implements saccade and smooth pursuit based on the three-dimensional coordinates of target is proposed. An optimal observation position is defined for bionic eye based on three-dimensional coordinates. A kind of motion planning method with high accuracy is developed. The motion parameters of stepper motor consisting of angle acceleration and turning time are computed according to the position deviation, the target＇s angular velocity and the stepper motor＇s current angular velocity in motion planning. The motors are controlled with the motion parameters moving to given position with desired angular velocity in schedule time. The experimental results show that the bionic eye can move to optimal observation positions in 0.6 s from initial location and the accuracy of 3D coordinates is improved. In addition, the bionic eye can track a target within the error of less than 20 pixels based on three-dimensional coordinates. It is verified that saccade and smooth pursuit of bionic eye based on three-dimensional coordinates are feasible.

关键词： bionic eye saccade smooth pursuit motion planning observation position

A Review of Device-Free Indoor Positioning for Home-Based Care of the Aged:Techniques and Technologies

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Computer Modeling in Engineering & Sciences 2023年第6期135卷 1901-1940页

作者： Geng Chen Lili Cheng Rui Shao qingbin wang Shuihua wang College of Electronic and Information Engineering Shandong University of Science and TechnologyQingdao266590China School of Computer Science and Technology Henan Polytechnic UniversityJiaozuo454000China

With the development of urbanization,the problem of neurological diseases brought about by population aging has gradually become a social problem of worldwide *** leads to gradual degeneration of the central nervous system,shrinkage of brain tissue,and decline in physical function in many elderlies,making them susceptible to neurological diseases such as Alzheimer’s disease(AD),stroke,Parkinson’s and major depressive disorder(MDD).Due to the influence of these neurological diseases,the elderly have troubles such as memory loss,inability to move,falling,and getting lost,which seriously affect their quality of *** and positioning of elderly with neurological diseases and keeping track of their location in real-time are necessary and crucial in order to detect and treat dangerous and unexpected situations in *** that the elderly with neurological diseases forget to wear a positioning device or have mobility problems due to carrying a positioning device,device-free positioning as a passive positioning technology that detects device-free individuals is more suitable than traditional active positioning for the home-based care of the elderly with neurological *** paper provides an extensive and in-depth survey of device-free indoor positioning technology for home-based care and an in-depth analysis of the main features of current positioning systems,as well as the techniques,technologies andmethods they employ,fromthe perspective of the needs of the elderly with neurological ***,evaluation criteria and possible solutions of positioning techniques for the home-based care of the elderly with neurological conditions are ***,the opportunities and challenges for the development of indoor positioning technology in 6G mobile networks for home-based care of the elderly with neurological diseases are *** review has provided comprehensive and effective tracking and positioning techniques,technologies

关键词： Home-based care device-free neurological diseases indoor positioning positioning techniques and technologies positioning accuracy

Quantitative research of diagenesis:its effect on pore evolution of the Fuyu oil reservoir in the north Qijia region

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Mining Science and Technology 2010年第5期20卷 770-777页

作者： HAO Guoli SHAN Xuanlong LIU Wanzhu wang qingbin College of Earth Sciences Jilin University Changchun 130061 China Technical Department of Tianjin Subcompany of CNOOC Tianjin 300452 China

From observing cores of 18 wells,identifying 175 ordinary thin sections and 61 thin casting sections,energy spectrum analyses of 37 samples,homogenization temperature measurement of fluid inclusions of 11 samples,we determine the types of diagenesis and pores of the Fuyu oil reservoir in the north Qijia *** classified the pores and measured their plane porosity using CIA 2000,the software of rock image analysis,calculated the effect of different kinds of diagenesis on porosity,studied the controlling actions of diagenesis to pore evolution quantitatively,combined with burial history,thermal history and their diagenetic *** results show that mechanical compaction and carbonate cementation are the major destructive diagenesed,developed during early diagenesis *** reduction in porosity by mechanical compaction and carbonate cementation are about 25% and 8%,while the destructive intensity of siliceous cementation and clay mineral cementation is relatively much smaller,i.e.,the reduction of porosity is about 2% and 0.2% Dissolution is constructive diagenesis,the increment of porosity is about 6%.There are four diagenesis evolution stages,during which the porosity reduced from 30%～38% to 2%～20%.Mechanical compaction and early cementation are the main diageneses in the early diagenesis stages,when porosity was reduced to 2%～10%.Dissolution is the main diagenesis of an A I substage of the middle diagenesis stage,when porosity increased 1%～8%.The dissolution of the A Ⅱ substage of the middle diagenesis stage affected by late cementation,raised porosity 1%～5%.The porosity varied slightly during the middle stage B.

关键词： north Qijia region Fuyu oil reservoir diagenesis pore evolution quantitative research

Impacts of the COVID-19 pandemic on the dairy industry: Lessons from China and the United States and policy implications

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Journal of Integrative Agriculture 2020年第12期19卷 2903-2915页

作者： qingbin wang LIU Chang-quan ZHAO Yuan-feng Anthony KITSOS Mark CANNELLA wang Shu-kun HAN Lei Department of Community Development and Applied Economics University of VermontBurlingtonVermont 05405USA Rural Development Institute Chinese Academy of Social SciencesBeijing 100732P.R.China College of Economics and Management Inner Mongolia Agricultural UniversityHohhot 010018P.R.China UVM Extension University of VermontBurlingtonVermont 05405USA

The purposes of this study are to assess the COVID-19 pandemic’s impacts on the dairy industries in China and the United States and to derive policy recommendations for enhancing the diary industries’resilience to pandemics and other market ***,data from the two nations are used to analyze and compare the mechanisms through which the pandemic has affected their dairy industries and to discuss potential lessons from their *** findings suggest that this pandemic has heavily affected the dairy industries in both China and the United States through similar mechanisms,such as decreased farmgate milk prices,disruption and difficulties of moving milk within the supply chains,worker shortages,increased production costs,and lack of operating *** were also significant differences in the affecting mechanisms between the two nations,including transportation difficulties from widespread road closures and significant reduction in holiday sales of dairy products in China,and the shutdown of many dairy processors in the United States due to the closing of schools,restaurants,and *** government financial reliefs are highly needed to help many dairy farms and processors survive this pandemic in the short term,the dairy industries and governments need to work together to develop long-term strategies and policies to balance the industries’efficiency and flexibility,product specialization and diversification,supply chain integration and local food systems,and market mechanisms and policy regulations and interventions.

关键词： impacts of the COVID-19 pandemic dairy industry China the United States

Fast modeling of gravity gradients from topographic surface data using GPU parallel algorithm

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Geodesy and Geodynamics 2021年第4期12卷 288-297页

作者： Xuli Tan qingbin wang Jinkai Feng Yan Huang Ziyan Huang School of Geospatial Information The Information and Engineering UniversityZhengzhou 450001HenanChina

The gravity gradient is a secondary derivative of gravity potential,containing more high-frequency information of Earth’s gravity *** gradient observation data require deducting its prior and intrinsic parts to obtain more variational information.A model generated from a topographic surface database is more appropriate to represent gradiometric effects derived from near-surface mass,as other kinds of data can hardly reach the spatial resolution *** rectangle prism method,namely an analytic integration of Newtonian potential integrals,is a reliable and commonly used approach to modeling gravity gradient,whereas its computing efficiency is extremely low.A modified rectangle prism method and a graphical processing unit(GPU)parallel algorithm were proposed to speed up the modeling *** modified method avoided massive redundant computations by deforming formulas according to the symmetries of prisms’integral regions,and the proposed algorithm parallelized this method’s computing *** parallel algorithm was compared with a conventional serial algorithm using 100 elevation data in two topographic areas(rough and moderate terrain).Modeling differences between the two algorithms were less than 0.1 E,which is attributed to precision differences between single-precision and double-precision float *** parallel algorithm showed computational efficiency approximately 200 times higher than the serial algorithm in experiments,demonstrating its effective speeding up in the modeling *** analysis indicates that both the modified method and computational parallelism through GPU contributed to the proposed algorithm’s performances in experiments.

关键词： Gravity gradient Topographic surface data Rectangle prism method Parallel computation Graphical processing unit(GPU)

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HEPS光束线站光学棚屋辐射屏蔽设计

原子能科学技术 2025年第2期59卷 494-502页

作者：郭庆洋石泓刘琼瑶张会杰石澔玙马忠剑王庆斌中国科学院高能物理研究所北京100049

高能同步辐射光源(high energy photon source,HEPS)是一台能量为6 GeV、流强为200 mA的第4代同步辐射装置,建成之后将是我国拥有的第一台高能同步辐射光源。HEPS可以提供高达300 keV能量的X射线,具备建设80条以上高性能光束线站的容量... 详细信息

高能同步辐射光源(high energy photon source,HEPS)是一台能量为6 GeV、流强为200 mA的第4代同步辐射装置,建成之后将是我国拥有的第一台高能同步辐射光源。HEPS可以提供高达300 keV能量的X射线,具备建设80条以上高性能光束线站的容量。光束线站运行过程中不可避免地产生有害辐射,成为光源运行及维护过程中工作人员辐射剂量的直接来源。因此,采用棚屋整体屏蔽的方式包容有害辐射是很有必要的。光学棚屋作为光束线站中辐射最严重的区域,数量多达几十个,如何在满足防护需求的同时探索出可以灵活应用于各线站的屏蔽设计方案成为光束线站建设中亟待解决的问题。本文基于线站结构特点及源项类型,重点分析了光学棚屋内的辐射源项类型并提出了标准化屏蔽设计方案。结合束线设备种类及其布局,采用蒙特卡罗程序FLUKA和同步辐射计算软件STAC8模拟了光学棚屋内剂量分布及在屏蔽体内的衰减,给出了光学棚屋屏蔽墙体的建议厚度。合理的光学棚屋屏蔽体厚度可为HEPS束线提供辐射防护设计的依据。

关键词：光束线站光学棚屋气体轫致辐射同步辐射屏蔽设计

Radiation shielding for the first optics enclosure at the High Energy Photon Source beamlines

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Radiation Detection Technology and Methods 2021年第2期5卷 168-173页

作者： Pingcheng Liu Qiongyao Liu Zhongjian Ma Huijie Zhang Mingyang Yan qingbin wang Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science Center Dongguan 523803China University of Chinese Academy of Sciences Beijing 100049China

Purpose The High Energy Photon Source(HEPS)is currently under construction in China and will be the brightest synchrotron radiation facility in the *** solve the gas bremsstrahlung and synchrotron radiation hazard at HEPS beamlines,a comprehensive radiation study is *** The Monte Carlo method is used to analyze the radiation field in the first optics enclosure at HEPS ***,the radiation sources including gas bremsstrahlung and synchrotron radiation are ***,the distribution of the radiation field in the hutch is *** parameters and a typical beamline geometry are used in the ***,the shielding recommendations are *** and Conclusion In this paper,the considerations and bulk shielding design of the first optics enclosure at HEPS beamlines are *** design satisfies the requirements of the radiation safety principles.

关键词： Radiation shielding Gas bremsstrahlung Synchrotron radiation HEPS Beamlines

Research on radiation dose rate distribution in the backscattering neutron hall of CSNS

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Radiation Detection Technology and Methods 2020年第1期4卷 116-129页

作者： Qingbiao Wu Sixuan Zhuang Qiongyao Liu Hantao Jing Rong Ye Lun Li Yufei wang qingbin wang China Spallation Neutron Source(CSNS) Institute of High Energy Physics(IHEP)Chinese Academy of Sciences(CAS)Room A2-431No.1Zhongzhiyuan RoadDalangDongguan 523803China Dongguan Institute of Neutron Science(DINS) Dongguan 523808China

Purpose To evaluate the prompt and induced dose rate in backscattering neutron hall for radiation protection and safety *** The dose rates were calculated by Monte Carlo code FLUKA,with the"multi-step"simulation method based on traditional"two-step simulation"*** Operation time of staff workers does not need to be *** with the increase in beam power and irra-diation time,serious consideration might need to be taken as the dose rate of samples may be higher than the limit value.

关键词： CSNS Radiation Dose rate Backscattering neutron Monte Carlo