检索结果-内蒙古大学图书馆

26th Chinese control Conference, CCC 2007

作者： Zhou, Bin Duan, Guangren Lin, Zongli Center for Control Theory and Guidance Technology Harbin Institute of Technology P.O. Box 416 Harbin Heilongjiang 150001 China Charles L. Brown Department of Electrical and Computer Engineering University of Virginia P.O. Box 400743 Charlottesville VA 22904-4743 United States

ISBN: (纸本)7900719229

Low gain feedback has found several applications in constrained control systems, robust control and nonlinear control. Low gain feedback refers to a family of stabilizing state feedback gains that are parameterized in a scalar and go to zero as the scalar decreases to zero. Such feedback gains can be constructed either by an eigenstructure assignment algorithm or through the solution of a parametric algebraic Riccati equation (ARE). The eigenstructure assignment approach leads to feedback gains in the form of a matrix polynomial in the parameter, while the ARE approach requires the solution of an ARE for each value of the parameter. This paper proposes an alternative approach to low gain feedback design based on the solution of a parametric Lyapunov equation. Such an approach possesses the advantages of both the eigenstructure assignment approach and the ARE based approach. It also avoids the possible numerical stiffness in solving a parametric ARE and the structural decomposition of the open loop system that is required by the eigenstructure assignment approach.

关键词： Feedback

来源：评论

学校读者我要写书评

暂无评论

A new design of robust H∞ filters for uncertain discrete-time state-delayed systems

A new design of robust H∞ filters for uncertain discrete-ti...

引用

IEEE Conference on Decision and control

作者： Huijun Gao Xiangyu Meng Tongwen Chen Space Control and Inertial Technology Research Center Harbin Institute of Technology Harbin China Department of Electrical and Computer Engineering University of Alberta Edmonton Canada

This paper investigates the problem of H infin estimation for discrete-time systems with a time-varying delay in the state and parameter uncertainties residing in a polytope. A new filter design procedure is proposed, which is developed based on homogeneous polynomially parameter-dependent matrices of an arbitrary degree. A numerical example is given to illustrate the effectiveness and advantage of the proposed filter design methods.

关键词： Robustness Filtering Delay effects Filters Polynomials Space technology Robust control Delay estimation State estimation Time varying systems

来源：评论

学校读者我要写书评

暂无评论

A Biologically Inspired Modular Structure to control the Sit-to-Stand Transfer of a Biped Robot

A Biologically Inspired Modular Structure to Control the Sit...

引用

29th Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBS 2007), vol.8

作者： M. Emadi Andani F. Bahrami P. Jabedar Maralani School of Electrical and Computer Engineering (ECE) University of Tehran Iran Control and Intelligent Processing Center of Excellence (CIPCE) School of ECE University of Tehran Iran

In this study, a biologically inspired control structure to control the sit-to-stand (STS) transfer from a chair is developed and simulated. STS movement is consisted of two main phases. First phase of the movement is before leaving the seat (seat-off moment). In this phase seat reactions forces act on the body parts which are in contact with the seat. The second phase is after seat-off, where the only external forces acting on the body are ground reaction forces. A proper control algorithm of the STS transfer needs to consider switching between these two phases, which correspond to two different dynamical structures. The control structure developed and discussed in this work is based on the MOSAIC structure, proposed first by Wolpert and Kawato [1]. Original MOSAIC structure has a modular architecture which is based on multiple pairs of forward and inverse models of the dynamical system to be controlled, and each module is trained separately to learn one part of a given task. The number of effective modules is predetermined. We have developed a new method to train all modules simultaneously. This method is based on reinforcement and cooperative competitive learning, and the number of effective modules is determined automatically. In this study, the simulation was begun with four modules. Our results showed that only two modules out of four were selected to control the STS task. Responsibility of controlling the task was switched between the two modules around the seat-off moment. In the other words, the two modules were corresponding to the two phases of the STS.

关键词： Biological control systems Robots Sociotechnical systems Biological system modeling Automatic control Inverse problems Force control Artificial neural networks Learning systems Testing

来源：评论

学校读者我要写书评

暂无评论

H∞ fuzzy control with missing data

H∞ fuzzy control with missing data

引用

IEEE International Conference on Systems, Man and Cybernetics

作者： Huijun Gao Yan Zhao Tongwen Chen Space Control and Inertial Technology Research Center Harbin Institute of Technology Harbin China Department of Electrical and Computer Engineering University of Alberta Edmonton Canada

This paper investigates the problem of H infin fuzzy control of nonlinear systems under unreliable communication links. The nonlinear plant is represented by a Takagi-Sugeno fuzzy model, and the control strategy takes the form of parallel distributed compensation. The communication links, existing between the plant and controller, are assumed to be imperfect (that is, data-packet dropouts occur intermittently, which appear typically in a network environment), and stochastic variables satisfying the Bernoulli random binary distribution are utilized to model the unreliable communication links. Attention is focused on the design of H infin controllers such that the closed- loop system is stochastically stable and preserves a guaranteed H infin , performance. Two approaches are developed to solve this problem, based on quadratic Lyapunov function and basis- dependent Lyapunov function respectively. Several examples are provided to illustrate the usefulness and applicability of the developed theoretical results.

关键词： Communication system control Fuzzy systems Fuzzy control control systems Lyapunov method Stability analysis Nonlinear systems control system synthesis Space technology Stochastic processes

来源：评论

学校读者我要写书评

暂无评论

Hybrid WT Based-DCT Based Face Recognition

Hybrid WT Based-DCT Based Face Recognition

引用

IEEE International Conference on Signal Processing and Communications, ICSPC

作者： P. Abouzar S. Yousefi S. K. Setarehdan Graduate student of Digital communications Chalmers University of Technology Sweden Graduate Student in Electrical Engineering Oregon State University Corvallis OR USA Control and intelligent processing center of Excellence Faculty of Electrical and computer Engineering University of Tehran Iran

In this paper a robust face recognition algorithm based on both WT (wavelet transform) and DCT (discrete cosine transform) is presented. The proposed algorithm takes the advantage of data reduction property of both WT and DCT, hence a large reduction in the data size, while saving most of the information. Initially, 2D WT is used to compress the data at various levels, which also removes the high frequency noise from the input image. Then 1D DCT is applied to each column of the resulting image from the previous step for more data reduction. Finally, PCA (principle component analysis) is applied to extract principle components of the data in the training set. SVM (support vector machine) is then used to separate different classes (picture of different persons obtained at various conditions). Comparison of the proposed algorithm with previously reported WT based algorithm shows a significant improvement in the classification results.

关键词： Face recognition Discrete cosine transforms Discrete wavelet transforms Support vector machines Support vector machine classification Robustness Image coding Frequency Noise level Principal component analysis

来源：评论

学校读者我要写书评

暂无评论

Robust fault detection for discrete-time Markovian jump systems with mode-dependent time-delays

引用

控制理论与应用（英文版） 2007年第2期5卷 139-144页

作者： Hongru WANG Changhong WANG Shaqshuai MOU Huijun GAO School of Information ＆ Communication Engineering Harbin Engineering University Harbin Heilongjiang 150001 China Space Control and Inertial Technology Research Center Harbin Institute of Technology Harbin Heilongjiang 150001 China Department of Electrical and Computer Engineering The University of Alberta Edmonton Alberta T6G 2V4 Canada

This paper investigates a fault detection problem for a class of discrete-time Markovian jump systems with norm-bounded uncertainties and mode-dependent time-delays. Attention is focused on constructing the residual generator based on the filter of which its parameters matrices are dependent on the system mode, that is, the fault detection filter is a Markovian jump system as well. The design of fault detection filter is reduced to H-infinity filtering problem by using H-infinity control theory, which can guarantee the difference between the residual and the fault （or, more generally weighted fault） as small as possible in the context of enhancing the robustness of residual to modeling errors, control inputs and unknown inputs. Sufficient condition for the existence of the above filters is established by means of linear matrix inequalities, which can be readily solved by using standard numerical software. A numerical example is given to illustrate the feasibility of the proposed method.

关键词： Markovian jump system Time-delay Fault detection H-infinity filtering Linear matrix inequality Residual

来源：评论

学校读者我要写书评

暂无评论

AUTOMATIC BRAIN TUMOR SEGMENTATION USING TISSUE DIFFISIVITY CHARACTERISTICS

AUTOMATIC BRAIN TUMOR SEGMENTATION USING TISSUE DIFFISIVITY ...

引用

IEEE International Symposium on Biomedical Imaging

作者： Azadeh Yazdan-Shahmorad Hesamoddin Jahanian Suresh Patel Hamid Soltanian-Zadeh Radiology Department Henry Ford Health System Medical Image Analysis Laboratory Detroit MI USA Electrical and Computer Engineering Department Wayne State University Detroit MI USA Biomedical Engineering Department University of Michigan Ann Arbor MI USA Control and Intelligent Processing Center of Excellence Electrical and Computer Engineering Department Faculty of Engineering University of Tehran Tehran Iran

ISBN: (纸本)9781424406715;1424406714

Water diffusion measurements have been shown to be sensitive to tissue cellular size, extra cellular volume, and membrane permeability. Therefore, diffusion tensor imaging (DTI) by MRI can be used to characterize highly cellular regions of tumors versus acellular regions, distinguishing cystic regions from solid regions. An automatic segmentation method is proposed in this paper based on a multi-phase clustering algorithm to segment the brain tumors in a feature space extracted from DTI images. The algorithm is applied on images of a total of 20 patients with 4 different types of tumors. The tumor region segmentation was 92% accurate based on the segmentation results using anatomical images and 100% accurate based on biopsy results. In general, the segmentation results obtained by the proposed method revealed a strong agreement with the biopsy results and anatomical images, providing support for the accuracy and robustness of the proposed feature space and the segmentation procedure.

关键词： Neoplasms Image segmentation Diffusion tensor imaging Clustering algorithms Biopsy Permeability measurement Volume measurement Size measurement Biomembranes Magnetic resonance imaging

来源：评论

学校读者我要写书评

暂无评论

control of Discrete Linear Repetitive Processes with H and l2 - l Performance

Control of Discrete Linear Repetitive Processes with H and l...

引用

American control Conference (ACC)

作者： Ligang Wu James Lam Wojciech Paszke Krzysztof Galkowski Eric Rogers Space Control and Inertial Technology Research Center Harbin Institute of Technology Harbin China Department of Mechanical Engineering University of Hong Kong Hong Kong China Institute of Control and Computation Engineering University of Zielona Góra Zielona Gora Poland School of Electronics and Computer Science University of Southampton Southampton UK

This paper considers the control of discrete linear repetitive processes, which are a distinct class of two-dimensional (2-D) discrete linear systems, i.e. information propagation in two independent directions, which are of both system-theoretic and applications interest. In this paper we report new results on the design of control laws with guaranteed levels of performance. In particular, develop algorithms for the design of an H infin and lscr 2 - lscr infin dynamic output feedback controller which guarantees that the resulting controlled process is stable and has prescribed disturbance attenuation performance as measured by H infin and lscr 2 - lscr infin norms.

关键词： control systems Linear systems Algorithm design and analysis Space technology Iterative algorithms Process control Optimal control Stability analysis Convergence Cities and towns

来源：评论

学校读者我要写书评

暂无评论

On Estimation of Plant Dynamics and Disturbance from Input-Output Data in Real Time

On Estimation of Plant Dynamics and Disturbance from Input-O...

引用

IEEE Conference on control Technology and Applications (CCTA)

作者： Qing Zheng Linda Q. Gao Zhiqiang Gao The Center for Advanced Control Technologies Department of Electrical and Computer Engineering Cleveland State University Cleveland OH USA Department of Mathematics North Central College Naperville IL USA

This paper is concerned with the question of, for a physical plant to be controlled, whether or not its internal dynamics and external disturbances can be realistically estimated in real time from its input-output data. A positive answer would have significant implications on control system design, because it means that an accurate model of the plant is perhaps no longer required. Based on the linear extended state observer (LESO), it is shown that, for a nth order plant, the answer to the above question is indeed yes. In particular, it is shown that the estimation error (1) converges to the origin asymptotically when the model of the plant is given; (2) is bounded and inversely proportional to the bandwidth of the observer when the plant model is mostly unknown. Note that this is not another parameter estimation algorithm in the framework of adaptive control. It applies to a large class of nonlinear, time-varying processes with unknown dynamics. The solution is deceivingly simple and easy to implement. The results of the mathematical analysis are verified in a simulation study and a motion control hardware test.

关键词： control system synthesis Observers Estimation error Bandwidth Parameter estimation Adaptive control Mathematical analysis Analytical models Motion control Hardware

来源：评论

学校读者我要写书评

暂无评论

A Survey on Quantum Cryptographic Protocols and Their Security

A Survey on Quantum Cryptographic Protocols and Their Securi...

引用

Canadian Conference on electrical and computer engineering (CCECE)

作者： Chi-Hang Fred Fung Hoi-Kwong Lo Center for Quantum Information and Quantum Control Edward S. Rogers Sr. Department of Electrical and Computer Engineering and Department of Physics University of Toronto Toronto ONT Canada

Communications in secrecy are often required in many commercial and military applications. Unfortunately, many cryptographic schemes in use today such as public-key cryptography based on the RSA algorithm would be broken with either unanticipated advances in hardware and algorithm or the advent of quantum computers. Quantum cryptography, on the other hand, has been proven secure even against the most general attack allowed by the laws of physics and is a promising technology poised for widespread adoption in realistic cryptographic applications. Quantum cryptography allows two parties to expand on a secret key that they have previously shared. Various quantum cryptographic protocols have been proposed to perform this task. In this paper, we survey some popular quantum cryptographic protocols (including the famous Bennett-Brassard 1984 protocol) and discuss their security. Specifically, we consider their security in two cases: the ideal case where a perfect single-photon source is used and the practical case where a realistic laser source is used. We compare the protocols and find that the efficient six-state protocol outperforms the others both in the tolerable quantum bit error rate and in the key generation rate when a realistic laser source is used.

关键词： Cryptographic protocols Security Military computing Application software Quantum computing Military communication Public key cryptography Hardware Physics Bit error rate

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：