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基于特征结构配置的导弹可重构控制器设计 被引量:2
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作者 王青 孙蕊 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2008年第3期304-306,共3页
针对简化后的导弹姿态控制系统,运用特征结构配置法,提出了一种改进的控制系统的重构方法.根据输出反馈特征值配置原理,给出了原闭环系统特征结构的确定方法,并对可重构控制器的代价函数的确定方法进行了改进.这种算法通过输出反馈可以... 针对简化后的导弹姿态控制系统,运用特征结构配置法,提出了一种改进的控制系统的重构方法.根据输出反馈特征值配置原理,给出了原闭环系统特征结构的确定方法,并对可重构控制器的代价函数的确定方法进行了改进.这种算法通过输出反馈可以确保闭环系统的稳定性,同时可以解决故障前后系统阶数不一致的问题.仿真结果表明,该方法能够在保证故障后闭环系统稳定的基础上使系统性能得到最大可能的恢复. 展开更多
关键词 导弹 姿态控制系统 特征结构配制 重构
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医院绩效评估指标体系权重研究 被引量:48
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作者 蔡志明 刘颜 +3 位作者 王光明 陈春涛 王琦 卢祖洵 《中国卫生经济》 北大核心 2004年第8期34-35,共2页
指标权重系数的确定是绩效评估中重要的一步。利用层次分析法确定指标体系中各指标的权重系数,其各层一致性比率CR<0.10,表明该研究的指标体系及权重系数可用于不同级别医院之间的绩效评估。
关键词 医院 绩效评估 指标权重系数 配制结构 工作效率 医疗质量 经济效益 服务质量 发展潜力
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Polygynous Mating System and Behavioural Reason of Black Crested Gibbon (Nomascus concolor jingdongensis) at Dazhaizi,Mt.Wuliang, Yunnan,China 被引量:12
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作者 范朋飞 蒋学龙 +1 位作者 刘长铭 罗文寿 《Zoological Research》 CAS CSCD 北大核心 2006年第2期216-220,共5页
The field research on five black crested gibbon groups, recently performed at Dazhaizi, Mr. Wuliang, Central Yunnan, China, showed that all groups in the local population consisted of one adult male, two adult females... The field research on five black crested gibbon groups, recently performed at Dazhaizi, Mr. Wuliang, Central Yunnan, China, showed that all groups in the local population consisted of one adult male, two adult females and 2 - 5 sub-adults, juveniles and itfants. The mean group size was 6.2 in August 2003 and 6.4 in August 2005. Two subadult males disappeared from their natal home range and three newborns were given birth in Group 3 (G3) and G4 during this study. The two adult females in G1, G2 and G3 gave births and/or carried babies but at different times. There was no aggressive or dominating behaviour observed between the two adult females. One floating female was first seen in G3's territory on April 15, 2005. The two resident females interrupted her duet with adult male and chased her. We did not observe adult male chased this floating female and she left G3's territory 10 days later. Sub-adult males often kept distance with the family, and they often sang solo bouts in their natal territory before they dispersed. The sub-adult males and females dispersed from natal territory and two adult resident females rejected the third one, which might were the reasons why the black gibbon groups were polygyny in Dazhaizi. 展开更多
关键词 Nomascus concolor jingdongensis Group size and composition Social structure Polygyny Local population Wuliang Mountain
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北京铁路局走好局直管站段的第一步
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《铁路计算机应用》 2005年第5期54-54,共1页
2005年3月25日,铁道部正式开始实行局直管站段的新型运输生产模式。这种模式改变了北京铁路局的体制结构、运输生产结构,管理结构、网络结构、TMIS、ATIS等投产项目的软件技术结构以及设备的配制结构。在这次运输体制和运输生产结构... 2005年3月25日,铁道部正式开始实行局直管站段的新型运输生产模式。这种模式改变了北京铁路局的体制结构、运输生产结构,管理结构、网络结构、TMIS、ATIS等投产项目的软件技术结构以及设备的配制结构。在这次运输体制和运输生产结构调整的过程中,北京铁路局信息技术处发挥了主力军的作用,承担了北京铁路局调度系统、客票系统,货运计划系统,网络系统等24项计算机应用项目系统的切换和调度楼的综合布线等工作。 展开更多
关键词 北京铁路局 局直管站段 运输生产模式 体制结构 配制结构 软件技术结构 网络结构 管理结构
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Smart Grids with Intelligent Periphery:An Architecture for the Energy Internet 被引量:24
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作者 Felix F.Wu Pravin P.Varaiya Ron S.Y.Hui 《Engineering》 SCIE EI 2015年第4期436-446,共11页
A future smart grid must fulfill the vision of the Energy Internet in which millions of people produce their own energy from renewables in their homes, offices, and factories and share it with each other. Electric veh... A future smart grid must fulfill the vision of the Energy Internet in which millions of people produce their own energy from renewables in their homes, offices, and factories and share it with each other. Electric vehicles and local energy storage will be widely deployed. Internet technology will be utilized to transform the power grid into an energysharing inter-grid. To prepare for the future, a smart grid with intelligent periphery, or smart GRIP, is proposed. The building blocks of GRIP architecture are called clusters and include an energy-management system (EMS)-controlled transmission grid in the core and distribution grids, micro-grids, and smart buildings and homes on the periphery; all of which are hierarchically structured. The layered architecture of GRIP allows a seamless transition from the present to the future and plug-and-play interoperability. The basic functions of a cluster consist of (1) dispatch, (2) smoothing, and (3) mitigation. A risk-limiting dispatch methodology is presented; a new device, called the electric spring, is developed for smoothing out fluctuations in periphery clusters; and means to mitigate failures are discussed. 展开更多
关键词 smart grid future grid Energy Internet energy- management system integrating renewables power system operation power system control distribution automation systems demand-side management
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Bifurcation control and eigenstructure assignment in continuous solution polymerization of vinyl acetate 被引量:1
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作者 张楠 邱彤 陈丙珍 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第9期1523-1529,共7页
The major difficulty in achieving good performance of industrial polymerization reactors lies in the lack of understanding of their nonlinear dynamics and the lack of well-developed techniques for the control of nonli... The major difficulty in achieving good performance of industrial polymerization reactors lies in the lack of understanding of their nonlinear dynamics and the lack of well-developed techniques for the control of nonlinear processes, which are usually accompanied with bifurcation phenomenon. This work aims at investigating the nonlinear behavior of the parameterized nonlinear system of vinyl acetate polymerization and further modifying the bifurcation characteristics of this process via a washout filter-aid controller, with all the original steady state equilibria preserved. Advantages and possible extensions of the proposed methodology are discussed to provide scientific guide for further controller design and operation improvement. 展开更多
关键词 Vinyl acetate polymerization Nonlinear dynamics Bifurcation control Eigenvalue assignment Washout filters
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欧宝欧美佳——源自欧洲的高档体验
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《汽车维修》 2002年第8期36-36,共1页
作为欧宝家族的旗舰车型,欧美佳轿车以高雅的外形、精湛的制造工艺和卓越的动力表现赢得了欧洲用户的青睐.与中国市场其他同类进口高级轿车相比,欧美佳无论从外形、性能、配备、安全等方面都是佼佼者,并以优异的性价比在中国进口车市场... 作为欧宝家族的旗舰车型,欧美佳轿车以高雅的外形、精湛的制造工艺和卓越的动力表现赢得了欧洲用户的青睐.与中国市场其他同类进口高级轿车相比,欧美佳无论从外形、性能、配备、安全等方面都是佼佼者,并以优异的性价比在中国进口车市场上取得了良好的销售业绩. 展开更多
关键词 欧宝汽车 欧美佳轿车 内部装饰 技术参数 结构配制 安全性
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Cooperative Dynamics in Lattice-Embedded Scale-Free Networks
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作者 SHANG Li-Hui ZHANG Ming-Ji YANG Yan-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第9期411-415,共5页
We investigate cooperative behaviors of lattice-embedded scale-free networking agents in the prisoner'sdilemma game model by employing two initial strategy distribution mechanisms,which are specific distribution t... We investigate cooperative behaviors of lattice-embedded scale-free networking agents in the prisoner'sdilemma game model by employing two initial strategy distribution mechanisms,which are specific distribution to themost connected sites (hubs) and random distribution.Our study indicates that the game dynamics crucially dependson the underlying spatial network structure with different strategy distribution mechanism.The cooperators' specificdistribution contributes to an enhanced level of cooperation in the system compared with random one,and cooperationis robust to cooperators' specific distribution but fragile to defectors' specific distribution.Especially,unlike the specificcase,increasing heterogeneity of network does not always favor the emergence of cooperation under random mechanism.Furthermore,we study the geographical effects and find that the graphically constrained network structure tends toimprove the evolution of cooperation in random case and in specific one for a large temptation to defect. 展开更多
关键词 geographical networks prisoner's dilemma COOPERATION HETEROGENEITY
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Discussion on Present Situation and Countermeasures about the development of nursing human resources
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作者 Yuejiao Wang 《International English Education Research》 2015年第8期20-22,共3页
Nursing Human Resource Management is part of the human resources is nursing human resources by organizing nurses study, planning, training, and ultimately serve the medical career management stated objectives. Nursing... Nursing Human Resource Management is part of the human resources is nursing human resources by organizing nurses study, planning, training, and ultimately serve the medical career management stated objectives. Nursing human resource development of our human resources there are insufficient care, nurses configuration structure is irrational, the management system is not perfect, nurses are not high quality is the current status of nursing human resource mauagemenL and problems. This paper proposes a "human resource is the first resource" human resources management concept, has taken to develop a reasonable management mechanism, improve relevant laws and regulations of nursing human resources development, increase investment in education, strengthen education and training for nurses, the rational allocation of nursing human resources and other measures. In this paper, the connotation of Human Resources Management in the current situation as the starting point of care, from the current situation of nursing human resource development and the problems of the current situation of nursing human resource management and problems of nursing human resources management to discuss and propose appropriate for the development of human resource management solutions. 展开更多
关键词 human resources nursing human resources human resources management
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Utilization of Recycled Coarse Aggregate in Concrete Mixes
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作者 Akmal Abdelfatah Sami Tabsh Sherif Yehia 《Journal of Civil Engineering and Architecture》 2011年第6期562-566,共5页
In this paper, the effect of the source of recycled coarse aggregate on the properties of concrete is investigated. The tests were conducted on concrete made from three sources of recycled aggregates: (1) old concr... In this paper, the effect of the source of recycled coarse aggregate on the properties of concrete is investigated. The tests were conducted on concrete made from three sources of recycled aggregates: (1) old concrete with unknown strength, (2) old concrete with a known compressive strength of 21 MPa, and (3) old concrete with a known strength of 42 MPa. The three sources of recycled aggregates were used to produce new concrete with a target compressive strength of 21 MPa. The first and third sources of recycled aggregates were used in producing concrete with target strength of 42 MPa. A control mix was designed with aggregates from natural sources. The research included two methods of making recycled concrete. One concrete mix was produced using the recycled aggregate and adding more water than the control mix, to reach the target slump, while the second concrete mix was produced using the same amount of water as the control mix but with additional superplasticizer to maintain the target slump. The results obtained in this research showed that the concrete compressive strength depends on the source of recycled aggregates; the stronger the source of recycled aggregate, the higher the compressive strength of the produced concrete. Furthermore, the compressive strength of the first concrete mix was about 10%-20% lower than the compressive strength of the control mix. However, when superplasticizers were used, the compressive strength was around the same value as the control mix. 展开更多
关键词 Compressive strength CONCRETE ENVIRONMENT recycled concrete.
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Substituent groups from aromatic dicarboxylates modulated structural diversification in the assembly of Co(Ⅱ)complexes based on the bis-pyridyl-bis-amide ligands 被引量:2
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作者 WANG XiuLi MU Bao +4 位作者 LIN HongYan YANG Song LIU GuoCheng TIAN AiXiang ZHANG JuWen 《Science China Chemistry》 SCIE EI CAS 2013年第5期557-566,共10页
Four coordination polymers based on two bis-pyridyl-bis-amide ligands and three aromatic dicarboxylates with different substituent groups, namely, [Co(3-bpcb)x.5(NPH)(H20)]" 4H20 (1), [Co(3-bpcb)(NIPH)] ... Four coordination polymers based on two bis-pyridyl-bis-amide ligands and three aromatic dicarboxylates with different substituent groups, namely, [Co(3-bpcb)x.5(NPH)(H20)]" 4H20 (1), [Co(3-bpcb)(NIPH)] (2), [Co(3-bpcb)0.5(5-H2AIP)]" 2H20 (3), [Co(3-bpcd)0.5(5-H2AIP)(H20)]" 2H20 (4) [3-bpcb = N,N'-bis(3-pyridinecarboxamide)-l,4-benzene, 3-bpcd = N,N'-bis(3- pyridine)cyclohexane-l,4-dicarboxamide, H2NPH = 3-nitrophthalic acid, H2NIPH = 5-nitroisophthalic acid, 5-HaAIP = 5-aminoisophthalic acid] have been synthetized under hydrothermal conditions. Complex 1 displays a one dimensional (1D) chain based on the binuclear [Co2(NPH)2] units and 3-bpeb ligands, which is extended into a three dimensional (3D) supra- molecular framework through hydrogen bonding and n-n stacking interactions. In complex 2, the (3,5)-connected two dimen- sional (2D) layers are constructed from 1D Co-NIPH chains and bidentate-bridging 3-bpeb ligands. Complex 3 is a 2D double layer based on Co-5-H2AIP 2D layers and 3-bpeb pillars. Complex 4 also displays a 2D network, which is constructed from the Co-5-H2AIP 1D double chains and 3-bpcd ligands. Finally, complexes 2--4 are extended into 3D supramolecular frame- works by hydrogen bonding or n-re stacking interactions. The substituent groups of dicarboxylates play an important role in the assembly and structures of the title complexes. In addition, the fluorescent properties of complexes 1-4 and the electrochemi- cal behaviors of 3 and 4 at room temperature have been investigated. 展开更多
关键词 coordination polymer bis-pyridyl-bis-amide ligand hydrothermal reaction fluorescent property
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Mass transport through metal organic framework membranes 被引量:9
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作者 Yi Guo Xinsheng Peng 《Science China Materials》 SCIE EI CSCD 2019年第1期25-42,共18页
Metal-organic frameworks(MOFs), which are composed of metal nodes and organic ligands, possess crystal phase, ordered well-defined porous structure and large surface area. Since first reported in 1990, MOFs have attra... Metal-organic frameworks(MOFs), which are composed of metal nodes and organic ligands, possess crystal phase, ordered well-defined porous structure and large surface area. Since first reported in 1990, MOFs have attracted extensive attention and the fabrication of MOF membranes has expanded their applications and endowed them with a bright future in various fields. The mass transportation process through MOF membranes is vital during their diverse applications. In this review, the strategies of preparing continuous and well-intergrown MOF membranes are presented firstly.The selective transportation processes of gas molecules, liquid molecules and ions through MOF membranes are discussed in detail, respectively. The effects of pore entrance size, interaction, functional groups decorating on the ligands and guest components on mass transportation have been summarized in this review as well. In addition, MOF membranes with selective transportation performance demonstrate potential in separation, catalysis, energy transformation and storage devices,and so on. 展开更多
关键词 mass transportation metal-organic framework (MOF) membranes
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A review of heavy-duty legged robots 被引量:19
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作者 ZHUANG HongChao GAO HaiBo +2 位作者 DENG ZongQuan DING Liang LIU Zhen 《Science China(Technological Sciences)》 SCIE EI CAS 2014年第2期298-314,共17页
Heavy-duty legged robots have been regarded as one of the important developments in the field of legged robots because of their high payload-total mass ratio,terrain adaptability,and multitasking.The problems associat... Heavy-duty legged robots have been regarded as one of the important developments in the field of legged robots because of their high payload-total mass ratio,terrain adaptability,and multitasking.The problems associated with the development and use of heavy-duty legged robots have motivated researchers to conduct many important studies,covering topics related to the mechanical structure,force distribution,control strategy,energy efficiency,etc.Overall,heavy-duty legged robots have three main characteristics:greater body masses,larger body sizes,and higher payload-total mass ratios.Thus,various heavy-duty legged robots and their performances are reviewed here.This review presents the current developments with regard to heavy-duty legged robots.Also,the main characteristics of high-performance heavy-duty legged robots are determined and conclusions are drawn.Furthermore,the current research of key techniques of heavy-duty legged robots,including the mechanical structure,force distribution,control method,and power source,is described.To assess the transportation capacity of heavy-duty legged robots,performance evaluation parameters are proposed.Finally,problems that need further research are addressed. 展开更多
关键词 heavy-duty legged robot mechanical structure force distribution control method power source
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The evolution of copulation frequency and the mechanisms of reproduction in male Anolis lizards 被引量:1
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作者 Michele A. JOHNSON Mafia Veronica LOPEZ +4 位作者 Tara K. WHITTLE Bonnie K. KIRCHER Alisa K. DILL Divina VARGHESE Juli WADE 《Current Zoology》 SCIE CAS CSCD 2014年第6期768-777,共10页
The evolution of many morphological structures is associated with the behavioral context of their use, particularly for structures involved in copulation. Yet, few studies have considered evolutionary relationships am... The evolution of many morphological structures is associated with the behavioral context of their use, particularly for structures involved in copulation. Yet, few studies have considered evolutionary relationships among the integrated suite of structures associated with male reproduction. In this study, we examined nine species of lizards in the genus Anolis to determine whether larger copulatory morphologies and higher potential for copulatory muscle performance evolved in association with higher copulation rates. In 10--12 adult males of each species, we measured the size of the hemipenes and related muscles, the seminiferous tubules in the testes, and the renal sex segments in the kidneys, and we assessed the fiber type composition of the muscles associated with copulation. In a series of pbylogenetically-informed analyses, we used field behavioral data to determine whether observed rates of copulation were associated with these morphologies.We found that species with larger hemipenes had larger fibers in the RPM (the retractor penis magnus, a muscle that controls hemipenis movement), and that the evolution of larg- er hemipenes and RPM fibers is associated with the evolution of higher rates of copulatory behavior. However, the sizes of the seminiferous tubules and renal sex segments, and the muscle fiber composition of the RPM, were not associated with copulation rates. Further, body size was not associated with the size of any of the reproductive structures investigated. The results of this study suggest that peripheral morphologies involved in the transfer of ejaculate may be more evolutionarily labile than internal structures involved in ejaculate production. 展开更多
关键词 ANOLIS COPULATION Hemipenes LIZARDS REPRODUCTION Reptiles
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Predicting hiCE inhibitors based upon pharmacophore models derived from the receptor and its ligands 被引量:1
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作者 ZHANG GuoDong GE Hu +1 位作者 GU Qiong XU Jun 《Science China Chemistry》 SCIE EI CAS 2013年第10期1402-1412,共11页
Human intestinal carboxyl esterase (hiCE) is a drug target for ameliorating irinotecan-induced diarrhea. By reducing irinotecan- induced diarrhea, hiCE inhibitors can improve the anti-cancer efficacy of irinotecan. ... Human intestinal carboxyl esterase (hiCE) is a drug target for ameliorating irinotecan-induced diarrhea. By reducing irinotecan- induced diarrhea, hiCE inhibitors can improve the anti-cancer efficacy of irinotecan. To find effective hiCE inhibitors, a new virtual screening protocol that combines pharmacophore models derived from the hiCE structure and its ligands has been pro- posed. The hiCE structure has been constructed through homology techniques using hCESI's crystal structure. The hiCE structure was optimized via molecular dynamics simulations with the most known active hiCE inhibitors docked into the structure. An optimized pharmacophore, derived from the receptor, was then generated. A ligand-based pharmacophore was also generated from a larger set of known hiCE inhibitors. The final hiCE inhibitor predictions were based upon the virtual screening hits from both ligand-based and receptor-based pharmacophore models. The hit rates from the ligand-based and receptor-based pharmacophore models are 88% and 86%, respectively. The final hit rate is 94%. The two models are highly consistent with one another (85%). This proves that both models are reliable. 展开更多
关键词 carboxyl esterase PHARMACOPHORE virtual screening ANTI-CANCER
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农防林营造技术
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作者 杨耀银 《农村实用科技》 2001年第3期14-14,共1页
关键词 农防林 营造技术 树种选择 整地方式 精选壮苗 结构配制 病虫害防治 适当修枝 水肥管理 精心栽植
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