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Structure improvement and electrochemical studies of bipolar nickel metal hydride batteries for hybrid electric vehicles

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Journal of Harbin Institute of Technology(New Series) 2006年第3期13卷 311-314页

作者：邓超史鹏飞 dept. of Applied Chemistry Harbin Institute of TechnologyHarbin 150001China

Nickel metal hydride battery in bipolar design offers some advantages for its application as a power storage system for electric and hybrid vehicles. This paper deals with the structure design and electrochemical studies of bipolar Ni/MH batteries for hybrid vehicles. An improvement is applied in bipolar battery design, and such bipolar Ni/MH batteries with 5 sub-cells have been assembled and investigated. Testing results show that bipolar batteries with improved structure have better compression tolerance and cycle performance than conventional ones. In addition, the improved bipolar batteries display excellent large current discharge ability and high power density. As simulating working conditions for hybrid vehicles, the batteries show good stability during pulse cycles, which verifies the possibility of being used as a power storage device on hybrid vehicles.

关键词： structure improvement electrochemical studies bipolar Ni/MH battery

Analysis and improvement of missile three-loop autopilots

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Journal of Systems Engineering and Electronics 2009年第4期20卷 844-851页

作者： Lin Defu Fan Junfang Qi Zaikang Mou Yu dept. of Flying Vehicle Engineering Beijing Inst. of Technology Beijing 100081 P. R. China

The non-minimum phase feature of tail-controlled missile airframes is analyzed. Three selection strategies for desired performance indexes are presented. An acceleration autopilot design methodology based on output feedback and optimization is proposed. Performance and robustness comparisons between the two-loop and classical three-loop topologies are made. Attempts to improve the classical three-loop topology are discussed. Despite the same open-loop structure, the classical three-loop autopilot shows distinct characteristics from a two-loop autopilot with PI compensator. Both the two-loop and three-loop topologies can stabilize a static unstable missile. However, the finite actuator resource is the crucial factor dominating autopilot function.

关键词： missile control three-loop autopilot output feedback fin resource non-minimum phase system

Research on robust fault-tolerant control for networked control system with packet dropout

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Journal of Systems Engineering and Electronics 2007年第1期18卷 76-82页

作者： Huo Zhihong Fang Huajing dept. of Control Science and Engineering Huazhong Univ. of Science and Technology Wuhan 430074 P.R. China

A kind of networked control system with network-induced delay and packet dropout, modeled on asynchronous dynamical systems was tested, and the integrity design of the networked control system with sensors failures and actuators failures was analyzed using hybrid systems technique based on the robust fault-tolerant control theory. The parametric expression of controller is given based on the feasible solution of linear matrix inequality. The simulation results are provided on the basis of detailed theoretical analysis, which further demonstrate the validity of the proposed schema.

关键词： Networked control system (NCS) Fault-tolerant control (FTC) Asynchronous dynamical systems (ADS) Integrity design Packet dropout Time delay

On the Aesthetics of the Ephemeral: A Prolegomena to the Question of Architecture as a Marker of Temporality

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On the Aesthetics of the Ephemeral: A Prolegomena to the Que...

Adaptive neural network tracking control for a class of unknown nonlinear time-delay systems

实践大学设计学院 2009 design++国际设计研讨会

作者： Thomas Tilluca Han Architecture dept. Shih-Chien University College of design Symposium 2009

***:Framing the Question In our time of instant messaging,instant credit,instant noodles,and massive displacement of peoples(from countries,land,and jobs),we find a different angle of perception to what Heidegger called the"forgetting of Being"vis-a-vis the notion of man as"being-there"(Dasein).Our time is one in which the’there’is virtually present as the

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来源： cnki会议评论

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Journal of Systems Engineering and Electronics 2006年第3期17卷 611-618页

作者： Chen Weisheng Li Junmin dept. of Applied Mathematics Xidian Univ. Xi'an 710071 P. R. China

For a class of unknown nonlinear time-delay systems, an adaptive neural network （NN） control design approach is proposed. Backstepping, domination and adaptive bounding design technique are combined to construct a robust memoryless adaptive NN tracking controller. Unknown time-delay functions are approximated by NNs, such that the requirement on the nonlinear time-delay functions is relaxed. Based on Lyapunov-Krasoviskii functional, the sem-global uniformly ultimately boundedness （UUB） of all the signals in the closed-loop system is proved. The arbitrary output tracking accuracy is achieved by tuning the design parameters. The feasibility is investigated by an illustrative simulation example.

关键词： nonlinear time-delay system neural network adaptive bounding technique memoryless adaptive NN controller.

Improved algorithm for RDO in JPEG2000 encoder and its IC design

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Journal of Systems Engineering and Electronics 2006年第2期17卷 430-436页

作者： Xie Xiang Li Cruolin Zhang Chun Zhang Li Wang Zhihua dept. of Electronic Engineering Tsinghua Univ.Beijing 100084 P. R. China

An improved rate distortion optimization （RDO） algorithm in JPEG2000 is proposed. The proposed algorithm is suitable for integrated circuit （IC） implementation and can reduce 30% computational cost. A hardware architecture which includes control unit, memory, divider, data converter is also given to implement the algorithm. The circuit based on the improved algorithm is tested on FPGAs and integrated in a JPG2000 chip codec core.

关键词： rate distortion optimization JPEG2000 integrated circuit (IC) codec core.

NUMERICAL MODELING OF DONGZHUANG RESERVOIR ON JING RIVER

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Journal of Hydrodynamics 2001年第2期13卷 68-71页

作者： Yang, M. Zhang, H.Y. Zhang, J.H. Zhang, H.W. dept. 5 Beijing Univ. of Aero. and Astron. Beijing 100084 China

The Dongzhuang Reservoir will be constructed on the Jing River, which is laden with the highest sediment concentration in the world. The sediment problem is a key challenge for the reservoir design and management. This paper presents essential data, details of sediment scour and siltation calculated by the numerical modeling based on new fundamental equations. Calculated results prove that the reservoir could preserve long-term storage capacity with the operation was offered by the design department.

关键词： Flow of fluids Mathematical models Sediments Storage (materials)

THE COMPRESSION LS ESTIMATE OF REGRESSION COEFFICIENT IN MULTIVARIATE LINEAR MODEL

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Applied Mathematics and Mechanics(English Edition) 1994年第4期15卷 379-388页

作者：陈世基曾志斌 dept. of Mathematics Fujian Normal University Fuzhou Statistics Bureau of Fujian Province Fuzhou

In this paper, compression LS estimate (k) of the regression coefficient B isconsidered when the design matrix present ill-condition in multivariate linear *** MSE (mean square error)of the estimate(k)=Vec( (k))is less than theMSE of LS estimate β￣* of the regression coefficient β= Vec(B) by choosing the pa-rameter k. Admissibility , numerical stability and relative efficiency of (k)are proved. The method of determining k value for practical use is also suggested

关键词： multivariate linear model. least square estimate compression LSestimate mean square error

Maneuver and vibration reduction of flexible spacecraft using sliding mode/command shaping technique

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Journal of Harbin Institute of Technology(New Series) 2006年第4期13卷 477-488页

作者：胡庆雷马广富张伟 dept. of Control Science &Engineering Harbin Institute of Technology Shanghai Institute of Control Engineering

A generalized scheme based on the sliding mode and component synthesis vibration suppression (CSVS) method has been proposed for the rotational maneuver and vibration suppression of an orbiting spacecraft with flexible appendages. The proposed control design process is twofold: design of the attitude controller followed by the design of a flexible vibration attenuator. The attitude controller using only the attitude and the rate information for the flexible spacecraft (FS) is designed to serve two purposes: it forces the attitude motion onto a pre-selected sliding surface and then guides it to the state space origin. The shaped command input controller based on the CSVS method is designed for the reduction of the flexible mode vibration, which only requires information about the natural frequency and damping of the closed system. This information is used to discretize the input so that minimum energy is injected via the controller to the flexible modes of the spacecraft. Additionally, to extend the CSVS method to the system with the on-off actuators, the pulse-width pulse-frequency (PWPF) modulation is introduced to control the thruster firing and integrated with the CSVS method. PWPF modulation is a control method that provides pseudo-linear operation for an on-off thruster. The proposed control strategy has been implemented on a FS, which is a hub with symmetric cantilever flexible beam appendages and can undergo a single axis rotation. The results have been proven the potential of this technique to control FS.

关键词： vibration reduction component synthesis vibration suppression (CSVS) flexible spacecraft sliding mode control (SMC) attitude maneuver