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African swine fever and meat prices fluctuation:An empirical study in China based on TVP-VAR model

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Journal of Integrative Agriculture 2021年第8期20卷 2289-2301页

作者： li hui-shang HU Chen-pei LÜZheng li Mei-qi GUO Xin-zhu Agricultural Information Institute/Key Laboratory of Big Agri-Data of Ministry of Agriculture and Rural Affairs Chinese Academy of Agricultural SciencesBeijing 100081P.R.China International Statistical Information Center National Bureau of StatisticsBeijing 100826P.R.China School of Statistics and Mathematics Central University of Finance and EconomicsBeijing 100081P.R.China

African swine fever(ASF),a fatal disease outbroken in China in August 2018,has widely attracted social concern especially in the information *** occurrence of ASF led to an imbalance between supply and demand in pork and other meat *** a result,meat prices fluctuated greatly during the past year in *** measure ASF quantitatively,the internet public concern index about ASF was created using web crawler *** relationships between ASF and meat prices were analyzed based on time-varying parameter vector auto-regressive(TVP-VAR)*** results showed that there were some differences in the impact size,direction and duration of ASF on the prices of pork,chicken,beef and mutton,and the characteristics of time variability and heterogeneity were *** the same time,the impact of ASF on meat prices is not consistent with the trend and degree of *** impulse intensity is strongly correlated with the strength and duration of ASF,and it is generally weak in the early stage and much stronger in the middle and late *** results indicate that macro regulations,monitoring and early-warning system,standardizing production and circulation,and the public opinion monitoring and guidance about ASF should be given more attention in future to stabilize the market expectations and to promote a smooth functioning of the livestock markets.

关键词： African swine fever meat prices dynamic transmission TVP-VAR model

Optimization Design for Digital Binoculars

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Semiconductor Photonics and Technology 2005年第3期11卷 212-216页

作者： CEN Jun-bo CHEN Wei-min li hui HUANG shang-lian Key Lab. for Optoelectron. Technol. ＆ Syst. Chongqing University Chongqing 400044 CHN

In order to develop competitive and high performance/cost ratio of digital binoculars, design scheme should be optimized in term of technical capacity, economic benefit, product performance, risk management, etc. The common optimization method is limited in qualitative analysis, and the parameter optimization method is limited in obtaining optimal parameter only from technical side. Each method has its limitation. Based on the analysis of digital binoculars parameters, optional design schemes are laid down. Analytic hierarchy process combined the qualitative analysis with the quantitative analysis together. The design schemes are optimized, and resuh is worked out.

关键词： Digital binoculars Design scheme Optimization

Modeling and Solving Human Arm’s Posture in Reachablity Analysis

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Computer Aided Drafting,Design and Manufacturing 2009年第1期19卷 64-68页

作者： liANG Ke-shan CAO Yu-jun TANG li ZHOU shang-hui College of Mechatronics Engineering and Automation National University of Defense Technology Changsha 410073 China

Reachability is a key criterion in maintenance design, and human arm is the main object in reachability analysis. The human arm＇s DOF is reduced, and applying military standards and human physiological constraints, the simplified arm model of 7-DOF using D-H method is built up. Particle Swarm Optimization （PSO） is used to acquire the shoulder, arm and hand posture with adaptive fitness function. A detailed reachability analysis is accomplished for disassembling the bolts from crank shaft is given as an example to validate the feasibility of using teachability analysis on maintenance design.

关键词： reachability D-H method particle swarm adaptive fitness function

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非流形几何造型技术与应用

计算机辅助设计与图形学学报 1998年第5期10卷 393-399页

作者：冯力叶尚辉西安电子科技大学电子机械学院

从非流形形体的表示方法和操作两个方面，对非流形几何造型技术进行了分析，探讨了其可能的应用领域．

关键词：非流形几何造型 CAD CAM

Influence of delayed position feedback on safe basins in a parametrically excited system

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Influence of delayed position feedback on safe basins in a p...

Decoding the nexus:branched-chain amino acids and their connection with sleep,circadian rhythms,and cardiometabolic health

第五届国际非线性力学会议

作者： hui-li shang Jian Xu (School of Aerospace Engineering and Applied Mechanics Tongji University shanghai 200092 China)

＜正＞The effects of delayed position feedback on controlling erosion of safe basin in a parametrically excited system were numerically *** focus was on the effect of time delay to the safe basin under the delayed position feedback *** action of feedback parameter was also *** minimum and maximal values of feedback-gain coefficient to prevent the basin from erosion were given along with the delay *** results show that the delayed position feedback control is an efficient strategy for controlling the extent and rate of the erosion.

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来源： cnki会议评论

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Neural Regeneration Research 2025年第5期20卷 1350-1363页

作者： hui li Laurent Seugnet Department of Neurology Xijing HospitalXi’anShaanxi ProvinceChina Centre de Recherche en Neurosciences de Lyon Integrated Physiology of the Brain Arousal Systems(WAKING)UniversitéClaude Bernard Lyon 1INSERM U1028CNRS UMR 5292BronFrance

The sleep-wake cycle stands as an integrative process essential for sustaining optimal brain function and,either directly or indirectly,overall body health,encompassing metabolic and cardiovascular *** the heightened metabolic activity of the brain,there exists a considerable demand for nutrients in comparison to other *** these,the branched-chain amino acids,comprising leucine,isoleucine,and valine,display distinctive significance,from their contribution to protein structure to their involvement in overall metabolism,especially in cerebral *** the first amino acids that are released into circulation post-food intake,branched-chain amino acids assume a pivotal role in the regulation of protein synthesis,modulating insulin secretion and the amino acid sensing pathway of target of ***-chain amino acids are key players in influencing the brain's uptake of monoamine precursors,competing for a shared *** their involvement in protein synthesis,these amino acids contribute to the metabolic cycles ofγ-aminobutyric acid and glutamate,as well as energy ***,they impact GABAergic neurons and the excitation/inhibition *** rhythmicity of branchedchain amino acids in plasma concentrations,observed over a 24-hour cycle and conserved in rodent models,is under circadian clock *** mechanisms underlying those rhythms and the physiological consequences of their disruption are not fully *** sleep,obesity,diabetes,and cardiovascular diseases can elevate branched-chain amino acid concentrations or modify their oscillatory *** mechanisms driving these effects are currently the focal point of ongoing research efforts,since normalizing branched-chain amino acid levels has the ability to alleviate the severity of these *** this context,the Drosophila model,though underutilized,holds promise in shedding new light on these *** findings indicate its po

关键词： branched-chain amino acids cardiovascular health circadian clock drosophila insulin metabolism sleep γ-aminobutyric acid

电热塞点火微型内燃机燃烧特性及残余废气对其的影响

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吉林大学学报（工学版） 2017年第3期47卷 811-818页

作者：唐志刚张力尚会超吕晓惠陈曦郑仁蔚重庆大学汽车工程学院重庆400044

为了评估二冲程电热塞点火微型内燃机的燃烧特性,构建了测试平台进行燃烧测试。与常规汽油机对比分析表明:微型内燃机放热率低、循环变动大、燃烧持续期长,比常规尺寸机型燃烧持续期长约20°CA,并且平均指示压力(p_(mi))和燃烧压力低;... 详细信息

为了评估二冲程电热塞点火微型内燃机的燃烧特性,构建了测试平台进行燃烧测试。与常规汽油机对比分析表明:微型内燃机放热率低、循环变动大、燃烧持续期长,比常规尺寸机型燃烧持续期长约20°CA,并且平均指示压力(p_(mi))和燃烧压力低;电热塞点火形式无固定点火时间,燃烧始点波动很大,导致微空间燃烧不稳定。基于首着火循环的瞬态分析表明:微型内燃机较高的残余废气系数是微空间燃烧特性差的主要原因;无残余废气情况下,微型内燃机燃烧放热率曲线与常规机型相当,燃烧持续期约为22°CA,比稳定燃烧时缩短近50%;缸体温度和残余废气共同影响燃烧始点和燃烧持续期,但残余废气是主要影响因素;残余废气量和缸体温度越高,对应的pmi越低,当缸体温度为150℃时,稳定燃烧状态下的pmi仅为0.17 MPa。

关键词：动力机械工程车辆工程微型内燃机电热塞点火燃烧特性残余废气

浅谈国企推行财务共享服务中心对财会人员的职业影响

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中小企业管理与科技 2018年第1期2卷 60-61页

作者：李尚辉中冶天工集团有限公司天津300308

财务共享服务中心是国有企业发展的重点,以现阶段国有企业发展情况为基础,结合近年来财务共享服务中心推广情况,分析财务共享服务中心的含义,明确其对财务工作者带来的职业影响,以此为国有企业未来的发展奠定基础。

关键词：国企财务共享服务中心财务人员

区位效应对农户耕地撂荒行为的影响及异质性研究——基于4省529户农户调查的实证分析

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经济纵横 2020年第10期 86-95页

作者：李辉尚郭昕竺曲春红中国农业科学院农业信息研究所北京100081

本文基于4省529户农户的微观调研数据,运用Probit和Tobit模型重点探究了区位效应对农户耕地撂荒行为的影响及其地形异质性。结果表明:区位效应对农户耕地撂荒行为有显著影响,偏远地区农户更倾向于保留耕地,城郊地区农户的撂荒面积相对更... 详细信息

本文基于4省529户农户的微观调研数据,运用Probit和Tobit模型重点探究了区位效应对农户耕地撂荒行为的影响及其地形异质性。结果表明:区位效应对农户耕地撂荒行为有显著影响,偏远地区农户更倾向于保留耕地,城郊地区农户的撂荒面积相对更大;城镇距离和道路距离缩短使得农户撂荒可能性及耕地撂荒面积显著增加;区位效应对不同地形区农户耕地撂荒行为的影响具有异质性,在高原和山地最为显著,丘陵和中低山区农户耕地撂荒行为主要受道路距离影响。鉴于此,应健全完善城郊和交通便利区域耕地资源保护制度体系;夯实弱势区域低质耕地基础设施条件保障;因地制宜推进区域农业结构调整,提质增效;推动以新型农业经营主体为龙头的适度规模经营,多措并举,有效减少耕地撂荒,夯实"藏粮于地"战略基础。

关键词：耕地撂荒农户行为区位效应异质性