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SBA中生命周期费用预测算法库的研究

系统仿真学报 2009年第S2期21卷 23-25,30页

作者：宋明刘丽北京航空航天大学自动化科学与电气工程学院北京100083

基于仿真的采办(SBA:Simulation Based Acquisition)主要应用之一就是控制武器装备全生命周期费用(LCC:Life Cycle Cost)。费用的控制不应局限于其实际发生时去记录,事后进行评价,更加依赖于采办前期以及每个阶段对装备生命周期费用的... 详细信息

基于仿真的采办(SBA:Simulation Based Acquisition)主要应用之一就是控制武器装备全生命周期费用(LCC:Life Cycle Cost)。费用的控制不应局限于其实际发生时去记录,事后进行评价,更加依赖于采办前期以及每个阶段对装备生命周期费用的预测。目前的费用预测方法很多,对应于装备生命周期的各个阶段。建立算法库,将已有的算法融入其中,通过多种算法预测对比,提供较为准确的预测结果,供采办方的决策者进行择优,其仿真结果良好。

关键词：生命周期费用算法库基于仿真的采办遗传算法

Synchronization of N Different Hyperchaotic Systems

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Synchronization of N Different Hyperchaotic Systems

2.09中国控制与决策会议

作者： Lingling Tian~1,Donghai Li~2.Xianfang Sun~1 1.School of Automation science and Electrical engineering,Beihang {2.,100083.beijing,china 2.State Key Laboratory of Power System,Dept of Thermal engineering,Tsinghua {2.,100084 beijing,china

＜正＞This study addresses the synchronization of N different hyperchaotic *** robust controllers with state variable error feedback and nonlinear compensating mechanisms are designed,such that the states of N different hyperchaotic systems are asymptotically *** to the Lyapunov stability theorem,the asymptotic stability of the solutions of the state error system is *** hyperchaotic Lorenz system,the hyperchaotic Liu system and the hyperchaotic Rossler system are taken as examples,numerical simulations and theoretical analysis show that the controller is effective and feasible.

关键词： Chaos Synchronization Lyapunov Stability Theory Different Hyperchaotic System

Mechanical behaviors of alumina ceramics doped with rare-earth oxides

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Rare Metals 2010年第5期29卷 456-459页

作者： YAO Yijun LI Chuncheng WANG Ling JIANG Xiaolong QIU Tai School of Mathematics and Physics Nanjing University of Information Science & Technology Nanjing 210044 China College of Materials science and engineering Nanjing University of Technology Nanjing 210009 China

The effects of three types of additives Y2.3, La2.3, and Sm2.3 on the sintering and mechanical behaviors of alumina ceramics were investigated. The bending strengths of alumina ceramics with Sm2.3 and Y2.3 additions were 455 and 439 MPa, respectively, higher than that with La2.3 addition. The fi＇acture toughness of the ceramics with Sm2.3 and Y2.3 were also higher than that with La2.3 addition. The fracture mode of rare earth oxides doped alumina ceramics exhibited obvious transgranular fractures as well as intergranular fracture. The results of research show that the improvement of bending strength and fracture toughness of alumina ceramics with rare earth oxides was achieved by refining the grain size and strengthening the grain boundary.

关键词： rare earths alumina doping mechanical properties microstructure

On the Recursive Implementation of Adaptive Control for Robot Manipulators

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On the Recursive Implementation of Adaptive Control for Robo...

第二十九届中国控制会议

作者： WANG Hanlei National Key Laboratory of science and technology on Space Intelligent Control,{2. institute of Control engineering,{2. 100190,P.R.china

This paper investigates the recursive implementation of adaptive control for robot *** the spatial vector tool and exploiting some physical properties of multi-body systems,we propose a general framework on the seeking of the Coriolis and centripetal matrix which satisfies the so-called skew-symmetric *** two existing choices are analyzed and a new kind of Coriolis and centripetal matrix is *** between these choices show that the simplest-form Coriolis and centripetal matrix comes from the original recursive Newton-Euler dynamics based on spatial vectors,which implies that skew-symmetric property is an inherent property possessed by spatial-vector based recursive Newton-Euler dynamics *** the proposed general framework regarding establishment of the Coriolis and centripetal matrix,a class of recursive passivity based adaptive algorithms have been *** the next,we present an algorithm on how to derive the filtered manipulator torque *** this filtered torque,the prediction error of the filtered torque is obtained and injected to the direct adaptation,forming the well-known composite adaptation *** adaptation driven by both the tracking errors and the prediction errors gives more smooth tracking error response and estimated parameter response,and also better tracking accuracy.A six-DOF manipulator is employed as a simulation example to show the performance of the proposed recursive algorithms.

关键词： Adaptive Control Recursive Implementation Robot Manipulators Uncertainties Passivity

Stabilization of Jump Linear Systems without Noise

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Stabilization of Jump Linear Systems without Noise

2.09中国控制与决策会议

作者： Liu Feng~1,H.B.Dong~2.Miaoyu~1 1.School of Electronics and Information engineering beijing Jiaotong {2.,beijing 100044 2.china institute for Actuarial science,Central {2. of Finance and Economic,beijing 100081,china

＜正＞The adaptive stabilization problem of linear systems with unknown parameters and without noise models is studied in this paper,we investigate continuous time jump linear systems with a finite-state hidden Markov jump form process.A sufficient condition characterizing the adaptive stabilizability of the system is found,which hings on the existence of a set of algebraic coupled Riccati *** is worth mentioning that a constructive method for designing stabilizing feedback law is provided in this paper.

关键词： Stabilization estimation jump linear systems coupled Riccati equations.

Kinematics Modeling and Experiments of Pectoral Oscillation Propulsion Robotic Fish

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Journal of Bionic engineering 2009年第2期6卷 174-179页

作者： Shao-bo Yang,Jing Qiu,Xiao-yun Haninstitute of Mechatronical engineering and Automatization,National {2. of Defense technology,Changsha 410073,P.R.china [a]institute of Mechatronical engineering and Automatization National University of Defense Technology Changsha 410073 P. R. China

A robotic fish driven by oscillating fins, 'Cownose Ray-I', is developed, which is in dorsoventrally flattened shape without a tail. The robotic fish is composed of a body and two lateral fins. A three-factor kinematic model is established and used in the design of a mechanism. By controlling the three kinematic parameters, the robotic fish can accelerate and maneuver. Forward velocity is dependent on the largest amplitude and the number of waves in the fins, while the relative contribution of fin beat frequency to the forward velocity of the robotic fish is different from the usual result. On the other hand, experimental results on maneuvering show that phase difference has a stronger effect on swerving than the largest amplitude to some extent. In addition, as propulsion waves pass from the trailing edge to the leading edge, the robotic fish attains a backward velocity of 0. 15 m·s^(-1).

关键词： robotic fish pectoral oscillation propulsion largest amplitude number of waves fin beat frequency phase difference

Characterization of polycyclic aromatic hydrocarbons in atmospheric PM10 from different functional zones of beijing in winter

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Characterization of polycyclic aromatic hydrocarbons in atmo...

第十届全国气溶胶会议暨第六届海峡两岸气溶胶技术研讨会

作者： Xue-Ling DONG 1,Da-Meng LIU 2.Shao-Peng GAO 3,Yang-Sen YUAN 4 1 School of Materials science and engineering,{2. university of Geosciences,beijing 100083.{2. 2.School of Energy Resources,{2. university of Geosciences,beijing 100083.{2. 3 institute of Tibetan Plateau research,Chinese Academy of sciences,beijing 100085,{2. 4 The Second Geology Company,Henan Province Bureau of Geology and Mineral Resources,Jiaozuo 454000,{2.

Polycyclic aromatic hydrocarbons（PAHs） are ubiquitous pollutants in the urban *** investigation on spatial variations of PAHs in the urban atmosphere of beijing during cold weather periods was conducted in this ***10 samples were collected at nine sites between December 2.05 and January *** were analyzed by GC-MS（gas chromatography-mass spectrometry）.16 PAHs,chemically characterized in the PM10 collected at nine locations of beijing only accounted for 0.1%-0.77% of aromatic hydrocarbons and 0.002.-0.2. of the extractable organic matter（EOM）,*** of the total PAHs in beijing city varied from 7.4 to 175.7 ng.m-3,with an average value of 44.1ng.m-3,which is lower than the data obtained from the contrast zone-Ming Tombs *** following scale of decreasing concentration in different zones was found:industrial zones＞contrast zone＞domestic zones＞commercial zones＞traffic ***,analysis of the relative distribution and diagnostic ratios of PAHs indicated that the site differences in the particulate PAH profiles were small with the exception of the coal burning heavily impacted locations and coal burning emissions are the most important sources of PAHs in beijing during the *** appears that a relatively stable profile exists for atmospheric particulate PAHs between locations in beijing,so the PAHs detected at many sites originated from multiple sources.

关键词： PM10 polycyclic aromatic hydrocarbons spatial variation beijing winter

A Kind of Arc-length Method for Ordinary Differential Equations

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Communications in Nonlinear science and Numerical Simulation 1997年第3期 15-20页

作者： Jike WU, Grafton W. H. HUI & Hongli DING (Department of Mechanics & engineering science,Peking {2., Peking, china) (Department of Mathematics, Hong Kong {2. of science and technology, china)

ＡＫｉｎｄｏｆＡｒｃ－ｌｅｎｇｔｈＭｅｔｈｏｄｆｏｒＯｒｄｉｎａｒｙＤｉｆｅｒｅｎｔｉａｌＥｑｕａｔｉｏｎｓ１ＪｉｋｅＷＵ，ＧｒａｆｔｏｎＷ．Ｈ．ＨＵＩ＆ＨｏｎｇｌｉＤＩＮＧ（ＤｅｐａｒｔｍｅｎｔｏｆＭｅｃｈａｎｉｃ... 详细信息

ＡＫｉｎｄｏｆＡｒｃ－ｌｅｎｇｔｈＭｅｔｈｏｄｆｏｒＯｒｄｉｎａｒｙＤｉｆｅｒｅｎｔｉａｌＥｑｕａｔｉｏｎｓ１ＪｉｋｅＷＵ，ＧｒａｆｔｏｎＷ．Ｈ．ＨＵＩ＆ＨｏｎｇｌｉＤＩＮＧ（ＤｅｐａｒｔｍｅｎｔｏｆＭｅｃｈａｎｉｃｓ＆ＥｎｇｉｎｅｅｒｉｎｇＳｃｉｅ...

关键词： Ordinary Differential Equations Numerical Method Arc length method Stiff Equation Burger′s Equation

Factors Affecting the Relation of Fracture Toughness V_(GC) with Critical Void Growth Ratio R_C/R_O

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Journal of Materials science & technology 1998年第6期14卷 574-576页

作者： Li ZHOU(Department of Civil engineering, Wuyi university,Jiangmen 52.02., {2.) Department of Civil engineering Wuyi University Jiangmen 529020 China

The relationship between fracture toughness VGC and critical void growth RC/RO was studied for ten kinds of Steel. The macroscopic fracture toughness VGC was determined by using notched tensile specimens. and the microscopic parameters of critical void growth ratio RC/RO were quantitatively measured under SEM. Then, the coefhcient C in the relation VGC = C In(RC/RO) proposed in author's past work was specifically explored. The correlation of C with tensile proderty parameter φ=σyδ/(Eφn) was presented for the Steel investigated, and the effects of low temperature on C were also discussed. Results show that the coefficient C is linearly related to the parameter and insensitive to low temperature.

关键词： GC with Critical Void Growth Ratio R_C/R_O Factors Affecting the Relation of Fracture Toughness V