摘要:

Beginning with the well-known concept of a system at the third level of generalization, where it is associated with empirical engineering and science, several new system categories are proposed. These are related to deterministic and stochastic distinctions and show clearly whether system disturbances are internally or externally generated. They are therefore valuable in both input/output and structural approaches for developing conceptual system models and choosing mathematical formalisms. By combining these categories with the concepts of autonomy and non-autonomy, new and more precise definitions for stationarity and non-stationary are formulated. In this way it is shown how the steady-state properties of systems may be inferred from knowledge of their internal properties and from the steady-state levels of inputs or parameters. Several examples are presented to demonstrate how the proposed definitions usefully relate general system concepts to specific physical system properties.

ISSN:0020-7721    

DOI:10.1080/00207727708942103

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

An ordering policy in which a working item can be replaced by an item supplied by order with load time is considered. We discuss the optimum ordering policy minimizing the expected cost per unit time for an infinite time span. It is shown in n, theorem that there exists a finite and unique optimum policy under suitable conditions. A sub-optimum policy is also presented.

ISSN:0020-7721    

DOI:10.1080/00207727708942104

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The design of an optimal m-sequence input signal for the identification of linear systems is considered for practical situations, where both the maximum amplitude as well as the duration must be constrained to finite values. A simple criterion for computing the minimum observation time is also proposed.

ISSN:0020-7721    

DOI:10.1080/00207727708942105

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The use of entropy as a measure of decision makers subjective uncertainty is an unexplored area in the economics of firm decision making. An information model that employs entropy as a measure of randomness is used to form the structure of a firm decision problem. By allowing for the feedback of information through an adjustment formula the decision makers uncertainty as to the best strategy available is reduced.

ISSN:0020-7721    

DOI:10.1080/00207727708942106

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

A brief overview of the orb-web construction is presented. Computer situation, in combination with 2-D Fourier transform of the hologram image, is a method of discriminating between realistic and unrealistic hypotheses about which cues are used in orb-web construction. The potential applications of coherent spatial filtering were particularly evident in the field of orb-web transformation, and this method stimulated additional interest in these techniques. The most important result of this study has been the demonstration that an apparently complex behaviour pattern can be simulated by making simple decision based on hologram image.

ISSN:0020-7721    

DOI:10.1080/00207727708942107

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

In this paper a linearized version of an ‘ industrial dynamics ’ simulation mode discussed by Forrester (1061) is presented and analysed. It is shown that at least for the stop change in final demand treated by Forrester (19R1) the behaviour of the linearized model presented here is not dissimilar to the behaviour of Forrester's nonlinear model. Analysis of the linearized model shows that the poor transient behaviour of the system is due primarily to the modes associated with the exponential smoothing of the demand.

ISSN:0020-7721    

DOI:10.1080/00207727708942108

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

In this paper it. is shown that Pontryagin's maximum principle can be used to set up an economic optimal control dynamic system which is composed of a pair of differential equations for employment and labour to investigate the long-run dynamic behaviour of capital and employment, the cyclical fluctuations of employment, and the producers' optimal employment policy that can be characterized by the dual meanings of the Pontryagin multiplier. One equation implies that money is not neutral because it has positive impact on employment while another equation implies that unemployment and inflation may happen simultaneously, as we have experienced in recent years.

ISSN:0020-7721    

DOI:10.1080/00207727708942109

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The following matrix differential equation initiated by research of dynamical network models is studied: φ=-P(φ t)a(t)a(t)TP(φT,t), where a is a vector-valued function of time t and P is a matrix-valued function of the solution matrix and time. A set of assumptions is given under which the solution, starting from a symmetric positive sotnidofinite initial matrix, tends asymptotically to a positive semidefinito matrix; if the initial matrix is a projection matrix and a(t) hua a special step-like structure, then the solution tends to a projection matrix on a specified subspace. Finally, a generalization of the basic class of equations is studied and an explicit expression is given for the limit matrix under certain conditions.

ISSN:0020-7721    

DOI:10.1080/00207727708942110

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

An existence theorem for optimal controls which transfer a fixed given function to a moving target set is shown for a class of non-linear systems containing time delays in both the state and control variables.

ISSN:0020-7721    

DOI:10.1080/00207727708942111

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor

摘要:

The optimal filtering problem for linear distributed systems with time delays having delayed measurements with coloured noise available on the boundary is considered. The innovations approach is used to derive the filter equations.

ISSN:0020-7721    

DOI:10.1080/00207727708942112

出版商:Taylor & Francis Group    

年代:1977

数据来源: Taylor