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基于Mahalanobis距离的多飞行器协同组网效能评估

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战术导弹技术 2024年第2期 62-70,134页

作者：张振宁王扬林涛魏佳宁张克航天科工智能运筹与信息安全研究院有限责任公司北京100074 常州大学常州213164

分层网络通信是多飞行器协同的关键所在,其效能评估结果对于体系优化决策至关重要。为解决传统效能评估方法忽略分系统效能散布、以欧氏距离平均值为参照带来的缺陷,提出基于Mahalanobis距离下的多飞行器分层网络效能评估体系模型。在... 详细信息

分层网络通信是多飞行器协同的关键所在,其效能评估结果对于体系优化决策至关重要。为解决传统效能评估方法忽略分系统效能散布、以欧氏距离平均值为参照带来的缺陷,提出基于Mahalanobis距离下的多飞行器分层网络效能评估体系模型。在构建出无人飞行器通信网络效能评估体系的基础上,利用Mahalanobis距离充分表征通信网络体系内各节点效能的随机分布情况。将Mahalanobis距离建模下的效能值作为BP神经网络的输入,对于分层协同组网效能进行建模,结合粒子群算法(Particle Swarm Optimization,PSO)优化BP神经网络进行求解,充分考虑分层网络的异构信息,对于评估复杂条件下的多飞行器通信效能有重要的意义。以多飞行器通信为例,建立基于Mahalanobis距离的网络效能评估体系,对于分层网络的效能进行评估。评估结果用于优化各节点的效能指标、分布情况以及可靠度,验证了方法的有效性,实现多飞行器网络通信效能的精准提升。

关键词：分层网络通信效能评估体系 Mahalanobis距离粒子群算法无人飞行器协同组网神经网络

持续被动活动结合阶段性康复锻炼对老年股骨颈骨折术后康复的影响

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国际医药卫生导报 2024年第18期30卷 3038-3042页

作者：段鹏飞魏佳宁南阳医学高等专科学校第一附属医院骨一科南阳473000

目的观察持续被动活动治疗仪结合阶段性康复锻炼对老年股骨颈骨折患者术后康复情况的影响。方法前瞻性选取2022年1月至2023年3月南阳医学高等专科学校第一附属医院收治的113例老年股骨颈骨折患者作为研究对象。采用电脑随机分组法生成... 详细信息

目的观察持续被动活动治疗仪结合阶段性康复锻炼对老年股骨颈骨折患者术后康复情况的影响。方法前瞻性选取2022年1月至2023年3月南阳医学高等专科学校第一附属医院收治的113例老年股骨颈骨折患者作为研究对象。采用电脑随机分组法生成随机序列,并进行分配隐藏后,将患者分为锻炼组(56例)和联合组(57例)。锻炼组男33例,女23例;年龄65~75(70.25±5.42)岁;病程7~14(10.24±2.33)d;Garden骨折分型:Ⅱ型30例,Ⅲ型26例。联合组男34例,女23例;年龄67~73(70.36±5.33)岁;病程8~13(10.32±2.19)d;Garden骨折分型:Ⅱ型32例,Ⅲ型25例。所有患者均实施手术治疗,术后锻炼组采用阶段性康复锻炼,联合组采用持续被动活动治疗仪结合阶段性康复锻炼。两组均治疗1个月,治疗结束后随访1年。比较两组髋关节活动度(屈曲、后伸、外旋、内收)、髋关节功能[Harris髋关节评分系统(HHS)、视觉模拟评分法(VAS)]、股静脉血流参数[血流峰值速度(Vp)、血流平均速度(Va)、血流量(BF)、血流阻力指数(RI)]。采用独立样本t检验、配对t检验和χ^(2)检验。结果治疗后,联合组髋关节屈曲[(80.33±10.45)°]、后伸[(12.33±3.25)°]、外旋[(33.49±5.41)°]、内收[(50.23±10.45)°]活动度均大于锻炼组[(75.29±10.41)°、(10.39±2.44)°、(30.25±5.28)°、(45.22±10.36)°](均P<0.05)。随访第6个月和第12个月,联合组HHS评分[(73.35±10.25)分、(82.49±10.44)分]均高于锻炼组[(68.42±10.44)分、(77.69±10.36)分],VAS评分[(4.33±1.25)分、(2.28±0.46)分]均低于锻炼组[(5.29±1.36)分、(3.36±0.45)分](均P<0.05)。治疗后,联合组股静脉Vp[(70.23±10.44)cm/s]、Va[(45.33±10.26)cm/s]均高于锻炼组[(65.44±10.28)cm/s、(40.29±10.36)cm/s],BF[(0.75±0.16)L/min]、RI[(1.33±0.72)kPa/s]均低于锻炼组[(1.25±0.46)L/min、(1.62±0.41)kPa/s](均P<0.05)。结论持续被动活动治疗仪结合阶段性康复锻炼可改善老年股骨颈骨折患者术后髋关节活动度和功能,对促进患者股静脉血流恢复有积极意义。

关键词：老年股骨颈骨折持续被动活动阶段性康复锻炼髋关节股静脉血流

Composition and emission dynamics of migratory locust volatiles in response to changes in developmental stages and population density

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Insect Science 2017年第1期24卷 60-72页

作者： jianing wei Wenbo Shao Xianhui Wang Jin Ge Xiangyong Chen Dan Yu Le Kang State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences Beijing China

Chemical communication plays an important role in density-dependent phase change in locusts. However, the volatile components and emission patterns of the migratory locust, Locusta migratoria, are largely unknown. In this study, we identified the chemical compositions and emission dynamics of locust volatiles from the body and feces and associated them with developmental stages, sexes and phase changes. The migratory locust shares a number of volatile components with the desert locust （Schistocerca gregaria）, but the emission dynamics of the two locust species are significantly different. The body odors of the gregarious nymphs in the migratory locust consisted of phenylacetonitrile （PAN）, benzaldehyde, guaiacol, phenol, aliphatic acids and 2,3-butanediol, and PAN was the dominant volatile. Volatiles from the fecal pellets of the nymphs primarily consist of guaiacol and phenol. Principal component analysis （PCA） showed significant differences in the volatile profiles between gregarious and solitary locusts. PAN and 4-vinylanisole concentrations were significantly higher in gregarious individuals than in solitary locusts. Gregarious mature males released significantly higher amounts of PAN and 4-vinylanisole during adulthood than mature females and immature adults of both sexes. Furthermore, PAN and 4-vinylanisole were completely lost in gregarious nymphs during the solitarization process, but were obtained by solitary nymphs during gregarization. The amounts of benzaldehyde, guaiacol and phenol only unidirectionally decreased from solitary to crowded treatment. Aliphatic aldehydes （C7 to C10）, which were previously reported as locust volatiles, are now identified as environmental contaminants. Therefore, our results illustrate the precise odor profiles of migratory locusts during developmental stages, sexes and phase change. However, the function and role of PAN and other aromatic compounds during phase transition need further investigation.

关键词： GC-MS/MS Locusta migratoria phase change phenylacetonitrile volatile chemicals

Linking ecosystem services and economic development for optimizing land use change in the poverty areas

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Ecosystem Health and Sustainability 2021年第1期7卷 37-48页

作者： Yinan Xu jianing wei Zhijun Li Yingxing Zhao Xinyu Lei Peng Sui Yuanquan Chen College of Agronomy and Biotechnology China Agricultural UniversityBeijingChina Office of Organic Agriculture Lingqiu County of Shanxi ProvinceDatongChina

For the sustainable development of human beings and society,it is important to conserve the ecosystems and alleviate poverty in the low agricultural productivity or ecologically vulnerable *** avoid the decrease in ecosystem services(ES)under the effects associated with reducing poverty,we need to carefully consider the relationship between land use changes and the economic development in economically poor *** selected the Lingqiu County as our study area,which is a national impoverished county in China,and analyzed the impact of poverty alleviation efforts on the ecological and economic sustainability in the region through ES *** results showed that land use change in the Lingqiu County has not changed the ES significantly during *** gross domestic product(GDP)growth rate(15.81%)during 2001-2016,indicates the effectiveness of the poverty alleviation efforts *** rise in the index of ecological and economic relationship during 2001-2016(from 0.2389 to 0.3629)maintains in a harmonious coordination ***,the value of ES has not been converted to market-based benefits,and therefore,it is indispensable to find a marketplace for ES(in an innovative way)to promote the high-quality sustainable development of a local economy.

关键词： Ecosystem services trade-off economic development land use change poverty alleviation

Quantitative evaluation modeling of mobile Ad Hoc networkcommunication service availability under failure|

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International Journal of Modeling, Simulation, and Scientific Computing 2020年第6期11卷 250-267页

作者： Yanfang Fu Yichang Su Zan Wang Dengdeng Guo Fei Dai Lianjiong Zhong jianing wei Xi’an Technological University State and Provincial Joint Engineering Lab.of Advanced Network Monitoring and Control Xi’an 710021P.R.China Beijing Electromechanical Engineering Institute Beijing 100074 P.R.China Science and Technology on Complex System Control and Intelligent Agent Cooperation Laboratory Beijing 100074 P.R.China

The availability of network communication services is an important evaluation standard to measure the ability of the network to meet the user’s business *** current related research mostly focuses on the evaluation of network reliability,which cannot reflect the logical relationship between failure/maintenance and network performance *** Ad Hoc Network is a multi-hop,centerless and energy-constrained distributed *** to the dynamic change of communication environment and the instability of wireless link,Ad Hoc Network is facing great challenges in service avail*** this thesis,a fault-based quantitative evaluation model of traffic availability in Ad Hoc networks is *** studying the multi-state Markov fault model of communication networks and the performance analysis of delay index based on CSMA\CA protocol,the quantitative evaluation of traffic availability in Ad Hoc networks is *** the availability of tactical unit network under different typical network configuration conditions is analyzed through experiments.

关键词： Network reliability service availability fault model quantitative evaluation

Optimum Tactics of Parallel Multi-Grid Algorithm with Virtual Boundary Forecast Method Running on a Local Network with the PVM Platform

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Journal of Computer Science & Technology 2000年第4期15卷 355-359页

作者：郭庆平章社生卫加宁 ComputerScienceDepartment WuHanTransportationUniversityWuhan430063P.R.China

In this paper, an optimum tactic of multi-grid parallel algorithmwith virtual boundary forecast method is disscussed, and a two-stage implementationis presented. The numerical results of solving a non-linear heat tran... 详细信息

关键词： algorithm parallel multi-grid virtual boundary forecast (VBF),speedup network computing PVM

2003年经济工作需要注意把握的几个重要关系

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金融研究 2003年第3期 1-10页

作者：魏加宁国务院发展研究中心宏观经济研究部北京100010

本文立足于改革,着眼于发展,针对2003年中国国内外的社会经济现实和经济环境进行了扼要的分析,以2003年我国经济良性运行为目的重点论述了如下几组需要认真把握的关系:形势大好与风险不小的关系;政策稳定与灵活调控的关系;扩大内需与艰... 详细信息

本文立足于改革,着眼于发展,针对2003年中国国内外的社会经济现实和经济环境进行了扼要的分析,以2003年我国经济良性运行为目的重点论述了如下几组需要认真把握的关系:形势大好与风险不小的关系;政策稳定与灵活调控的关系;扩大内需与艰苦奋斗的关系;扩大内需与改善供给的关系;引进外资与用好内资的关系;加快改革与防范风险的关系等。

关键词： 2003年经济工作宏观经济中国经济政策扩大内需艰苦奋斗外资利用风险防范

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国外地方政府债务融资制度综述

国家行政学院学报 2010年第6期 113-117页

作者：魏加宁唐滔国务院发展研究中心北京100010

本文介绍了政府债务融资的理论依据,分析和总结了国外地方政府的债务融资、发债制度的有关经验,以期对我国建立规范的地方政府投融资制度起到借鉴和启示作用。

关键词：地方政府债务融资制度国际经验

Preventing Financial Risks

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Beijing Review 2012年第1期55卷 34-35页

作者： wei jianing,Deputy Director of the Department of Macroeconomic Research of the Development Research Center of the State Council

The global economy faces an uncertain future. China also faces challenges to ensure steady economic development. wei Jianjing,Deputy Direclor of the Department of Macroeconomic Research of the Development Research Center of the State Council, shared his views withFinancial News on how China will prevent financial risks and reform its financial system in 2012. Edited excerpts follow：

关键词：金融风险防范国务院发展研究中心全球经济宏观经济金融体系中国