摘要:

In developmental systems without feedback, the growth is polynomial and a hierarchy exists between subsystems according to the location of the generating subword along the generating word; as a consequence, the possibility of regeneration after partial destruction is limited and relative stability of the system structure is observed if one letter is changed in the generating word. In developmental systems whose generating word has feedback the growth is exponential, regeneration may be complete following the survival of a unique element and changing one letter in the generating word may cause a complete change in the structure of the system.

ISSN:0020-7721    

DOI:10.1080/00207728708967104

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The system for scheduling and cleaning canal systems (SCCS) described in this paper serves for a proxi-optimal scheduling of cleaning operations for municipal canal systems. The ranking of the canal sections to be cleaned is provided in two independent ways and the plan is then established by an opportunistic compromise. The main characteristics of the expert system are its adaptability and capability for replacing lacking data in the data-base by default values. The paper reports on practical experience obtained with the SCCS system for a canal network of about 2000 sections.

ISSN:0020-7721    

DOI:10.1080/00207728708967105

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

In this paper, singular perturbation methods are used to synthesize high-gain error-actuated production control policies for a class of multi-stage manufacturing systems in which each manufacturing sub-system comprises either one or several production facilities. It is shown that when the manufacturing sub-systems are connected in cascade, each sub-system can be controlled in isolation, but that production control policies based on this approach lead to undesirable transient behaviour if the value of the feedback gain parameter is small. An alternative approach whereby production control policies are synthesized for the composite system leads to improved transient behaviour. However, if the value of the feedback gain parameter is large, both approaches are shown to yield good transient behaviour. In addition, it is demonstrated that trade-off between rapid adjustments in production rates and large inventory-level deviation can be achieved by selecting an appropriate value for the feedback gain parameter.

ISSN:0020-7721    

DOI:10.1080/00207728708967106

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

An adaptive algorithm is presented to incorporate deadbeat control as a principle design criterion. Since this algorithm does not require the solution of the diophantine equation at each sampling step, it possesses a computational advantage over the existing deadbeat control approaches, and so is suitable for application to adaptive systems. The meeting of the internal stability requirement enables this algorithm to handle easily any stable or unstable, minimum or non-minimum phase system. By selecting the zero assignment of the sensitivity function the system can be made to track a class of changeable reference signals and exhibit a deadbeat response with minimum settling time. Some constraints on the transfer function make sure that the derived controller is realizable. The non-linear saturated system and the lathe system are simulated to illustrate the validity of the proposed design algorithm.

ISSN:0020-7721    

DOI:10.1080/00207728708967107

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

This paper presents a new on-line procedure for identifying MIMO time-varying stochastic dynamic systems. It is based on a decomposition model derived from the state-space representation. This scheme gives an estimated model with a minimal number of parameters. The parameters of the MIMO system are identified from short records with unknown dead times. Extended recursive least-squares and fixed-lag smoothing identification algorithms are applied to identify the validity of the model structure. Artificial and hydrological records are used to illustrate the efficiency of the proposed procedure.

ISSN:0020-7721    

DOI:10.1080/00207728708967108

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

A method for optimally shifting the imaginary parts of the open-loop poles of a multivariable control system to the desirable closed-loop locations is presented. The optimal solution with respect to a quadratic performance index is obtained by solving a linear matrix Lyapunov equation.

ISSN:0020-7721    

DOI:10.1080/00207728708967109

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The problem of finding fault patterns consistent with a given syndrome is discussed for graph-theoretical diagnosis models such as the fault-diagnosis and self-diagnosis models. The fault-diagnosis model consists of two types of vertices, fault units and measurements, and is expressed by a bipartite graph. Faulty states of a fault unit always imply abnormal states of all the measurements which are adjacent to the unit, otherwise a measurement remains normal. A self-diagnosis model consists of one type of unit which has the capability of testing other units and being tested itself. The testing relation is represented by a directed arc; this produces test outcomes which are invalid if the testing unit is faulty. The inverse system which yields a fault pattern from a corresponding syndrome for fault-diagnosis models is studied and a syndrome-decoding algorithm is proposed which works for some class of diagnosis models with observation noise. The algorithm uses a similar measure to the syndrome-decoding algorithm of error-correcting codes which use the Hamming distance. Another measure is presented for the self-diagnosis model expressed by a directed graph and this measure is characterized by a ranking method.

ISSN:0020-7721    

DOI:10.1080/00207728708967110

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

This paper investigates convergence and optimality properties of the modified two-step algorithm for on-line determination of the optimum steady-state operating point of an industrial process. Mild sufficient conditions are derived for the convergence and feasibility of the algorithm. It is shown that every point within the solution set of the algorithm satisfies first-order necessary conditions for optimality, and that every optimal solution belongs to this set. It is also shown that there are advantages to be gained by using a linear mathematical model of the process within the implementation of the algorithm.

ISSN:0020-7721    

DOI:10.1080/00207728708967111

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The estimation error covariance of a fixed-point smoother in the steady-state, which has the steady-state solution of the Kalman filter as the initial condition, is considered for both continuous- and discrete-time systems. Applying some results on a stabilizing solution for a forward-pass fixed-interval smoother, a necessary and sufficient condition is given for assuring the existence of a unique stabilizing solution for such a fixed-point smoother. It is then shown that the resulting condition is equivalent to a well-known condition for the existence of a unique stabilizing solution of the Kalman filter or of the backward information filter.

ISSN:0020-7721    

DOI:10.1080/00207728708967112

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The approximation method in a Hilbert space is applied to the analysis of a generalized non-singular Sturm-Liouville eigenvalue problem. The variable coefficients in the system equation and the solution are approximated by a suitable linear independent basis, the expansion coefficients are explicitly expressed as a backward recursive formula and the eigenvalues are obtained by solving an algebraical characteristic equation. The computation is simple and straightforward.

ISSN:0020-7721    

DOI:10.1080/00207728708967113

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor