摘要:

The application of a causal dynamical observer-based controller for a linear time-invariant square singular system is considered. Sufficient conditions which constructively yield an approach for obtaining a reduced-order causal compensator that stabilizes the system, eliminates impulsive modes and estimates the system' s state have been established. In particular, the present approach establishes a clear and useful relation between the structure and the dimension of a minimal order compensator for state-space and singular systems, and generalizes the separation property in an obvious way

ISSN:0020-7721    

DOI:10.1080/00207729408928941

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

A general frequency domain stability criterion is presented for autonomous nonlinear dynamical systems that possess several non-linearities and several equilibrium states. As special cases, the result is shown to contain well-known criteria for non-oscillatory behaviour of non-linear feedback loops, of non-linear electrical RLC-circuits and analogue neural networks. The proof relies on a single Liapunov function which can subsequently be used lo compute regions of attraction for each of the equilibrium states. Therefore the result is particularly useful for the analysis and the design of systems such as neural classification networks, which possess many equilibrium states.

ISSN:0020-7721    

DOI:10.1080/00207729408928942

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

A two-stage algorithm is introduced to find the optimal (in the least-squares sense), linear approximate model of a non-linear steady-state composite system having a structure described by an interconnection matrix. First, an optimum linear model of a complex system as a whole is computed and then optimal parameters for the component submodels of the complex model maintaining the structure of the system, are derived in a decentralized manner. The particular form of the algorithm for series system is discussed separately. The practical utility of the approach is demonstrated by means of some examples.

ISSN:0020-7721    

DOI:10.1080/00207729408928943

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The problem of stabilizing uncertain discrete-time systems by observer-based control is considered. The uncertainties permitted in the systems are assumed to be structured and bounded but otherwise arbitrary. The design criterion is based on the quadratic stability of the overall closed-loop systems. By formulating the uncertainties in terms of quadratic bound matrices, a set of coupled generalized Riccati and Lyapunov equations (CGRLE) are derived. A less conservative design criterion can be obtained by recursively solving the CGRLE with the stability of the closed-loop system checked at each step. Examples are provided to illustrate the advantages of this method.

ISSN:0020-7721    

DOI:10.1080/00207729408928944

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The effect of linear feedback laws on the quadratic estimates of the stability regions of a class of non-linear systems is investigated. These linear feedback laws include state feedback laws, combined control laws and estimators, and dynamic output feedback laws via the factorization method. Some sufficient conditions are provided for these feedback laws to augment the quadratic estimates of the stability regions of non-linear systems.

ISSN:0020-7721    

DOI:10.1080/00207729408928945

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The problem of disturbance attenuation for large-scale systems using decentralized control is considered. The design procedure developed here involves constructing H∞ local state feedback controls via the Riccati equation approach, and a complete solution to this problem is carried out merely by iteratively solving a set of local algebraic Riccati equations. It is shown that when all the states are available, the H∞ norm of the closed-loop transfer function over all linear constant decentralized control laws is not imrpoved by allowing feedback to be dynamic. With successively smaller values of the prespecified disturbance level, the local state feedback H∞ suboptimal control problem can be solved and the controller can be chosen to be static.

ISSN:0020-7721    

DOI:10.1080/00207729408928946

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The design of a nearly decoupled, robust control system with an unstable plant is considered. The main aim is to present an effective design methodology that is applicable to a non-minimum phase and/or unstable multivariable uncertain plant. The controller resulting from the present design technique for nearly decoupled multivariable control has no right half-plane poles/zeros other than those specified by the designer, even when the given plant is of non-minimum phase and/or unstable. Unlike the prevailing techniques, the present approach can handle detailed and tight design requirements specified on the Bode array of the closed-loop system. Furthermore, a non-conservative robustness criterion presented in a previous paper is integrated into the design methodology such that the resultant design is robust in the presence of plant uncertainties.

ISSN:0020-7721    

DOI:10.1080/00207729408928947

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The present work proposes a method based on block pulse function ( BPF) analysis for the determination of cross-/ auto-correlation of time-varying signals. These results are used subsequently to evaluate power spectral densities ( PSD) of a few codes for communication. Two Lebesgue integrable time-varying functions are represented by means of their respective equivalent BPF spectra. The BPF spectral coefficients are used to develop positive and negative correlation matrices of an operational nature. These matrices, when combined, result in a correlation matrix that is used to determine cross-/ auto-correlation of the input functions over the entire time scale. The results thus obtained in the BPF domain are utilized to determine the PSDs of a few communication codes employing the well-known fast Fourier transform algorithm. Numerical experiments are carried out to establish the validity of the proposed method and the results are found to be in close agreement with the exact solutions

ISSN:0020-7721    

DOI:10.1080/00207729408928948

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

A discrete-time non-linear time series system of a cascade structure is identified. The system consists of a non-linear memoryless element followed by a dynamic linear subsystem. The non-linear characteristic is recovered with the help of the kernel regression estimate. The consistency of the estimate in the presence of correlated noise is examined. The rate of convergence as well as some variance reduction method are established. Data-driven techniques for selection of a smoothing parameter are discussed. The identification of a linear part of the system is also studied

ISSN:0020-7721    

DOI:10.1080/00207729408928949

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor

摘要:

The multi-stage Monte Carlo approach is similar to the regular Monte Carlo or random search approach that is frequently used on difficult multivariate problems. However, with multi-stage, the regular Monte Carlo search is considered to be stage one. This is followed by several more stages in an ever narrowing and re-positioning region following the best answers so far, hopefully on a trail to the optimal or a close approximation. The element of risk is certainly present in multi-stage Monte Carlo. Therefore to compare it with other algorithms for effectiveness, six test problems from the literature are selected and ‘ solved ’ with multistage. The results with multi-stage and other approaches are similar for the first five problems. However, in the last test problem, multi-stage finds many lower values than the stated ‘ minimum ’ and fourteen of them are presented here along with computer programs and a discussion of multi-stage Monte Carlo

ISSN:0020-7721    

DOI:10.1080/00207729408928950

出版商:Taylor & Francis Group    

年代:1994

数据来源: Taylor