摘要:

This paper presents a differential-difference equations model of a dynamic aquatic ecosystem. This paper departs from other models by considering : (a) specific phyla of phytoplankton, zooplankton and nekton ; (b) their prey—predation relationships ; (c) both allelochemic and antotoxic effects of algae upon zooplankton and other algae ; (d) inter-phyla competition for nutrients. Other factors included are : limiting effects of phosphates, nitrates, silicates, photoperiod, turbidity, temperature, and time lag, as they affect growth and reproduction of the biota. The model uses the western basin of Lake Erie as a test example, but any shallow basin that does not experience thermoclines could be used.

ISSN:0020-7721    

DOI:10.1080/00207727608941933

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

This paper considers the problem of finding necessary and sufficient conditions for stabilizing the linear systemx= Fx+Guby means of feedback control laws u=Kxmeasuring as few components ofxas possible. Easily computable conditions are given which insure that a given component ofxmay be eliminated from a stabilizing law (sufficiency), as well as simple conditions which must bo satisfied if a given component is to be so eliminated. Unfortunately, these conditions are not one and the same but numerical examples are given to demonstrate their utility none the less.

ISSN:0020-7721    

DOI:10.1080/00207727608941934

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

Two methods arc presented in the frequency domain for obtaining reduced models of multivariable systems with various numbers of inputs and outputs. The method of matrix continued fraction and the mixed method are extended to obtain the reduced models. When the ratio of the rank and the dimension of a transfer-function matrix is not an integer or the ratio is an integer but there exist numerically ill-conditioned elements in the matrix, a technique is proposed to deal with these cases.

ISSN:0020-7721    

DOI:10.1080/00207727608941935

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

In this paper the Brunovsky canonical form is used to synthesize control policies for a production-inventory tracking system. The theory is illustrated by the presentation of the results of computer-simulation studies of the response of a particular system of this class to typical command inputs.

ISSN:0020-7721    

DOI:10.1080/00207727608941936

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

The objective of this paper is to extend the frequency domain critorion for predicting the stability of a clas9 of linear time-varying-gain systems, subject to white Gaussian noise input disturbance.

ISSN:0020-7721    

DOI:10.1080/00207727608941937

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

This paper presents a method for generating near optimal closed-loop solutions to zero-sum perfect information differential games. Such a near-optimal solution is generated by periodically updating the solution to the two-point boundary-value problem (TPBVP) obtained from the application of the necessary conditions for a saddle-point solution. This procedure is accomplished by updating the co-state vector at each updating time based on the state error from a reference TPBVP solution. The relationship between the required change in the co-state vector and the state error is obtained using the transition matrices for the linearized TPBVP. Between updating times the player using this method plays his open-loop control determined from the updated TPBVP solution. A number of examples are presented to illustrate the advantages and shortcomings of this method.

ISSN:0020-7721    

DOI:10.1080/00207727608941938

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

Optimal distributed filters are designed for a class of linear Gaussian disturbed distributed-parameter systems. A direct approach, in which the Green's function and covariance matrices are expressed using a complete set of orthonormal basis, is used. Noisy measurements are assumed available at a finite number of fixed points in the space. The filter performance is demonstrated for a particular diffusion process together with the details of the numerical computations.

ISSN:0020-7721    

DOI:10.1080/00207727608941939

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

A new approach to non-linear programming is presented. The original non-linear programming problem is formulated as a sequence of unconstrained optimization problems. It is shown that this sequence will converge to the non-linear programming optimum. The proposed negative-positive harrier function has certain advantages over the usual barrier and penalty function methods. In addition, by minor modification of the new unconstrained objective function it is possible from a single optimization to see if there exists a feasible region.

ISSN:0020-7721    

DOI:10.1080/00207727608941940

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

In this paper a particular class of linear parametric stochastic systems is considered. For this class the moment stability problem is analysed: it is shown that the stability conditions do not depend on the noise bandwidth. An equivalent Ito equation is derived. Explicit criteria for the stability of the moments, forpth mean stability and for almost sure stability are obtained.

ISSN:0020-7721    

DOI:10.1080/00207727608941941

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor

摘要:

This paper extends a number of results on association of variables obtained earlier by the authors. Specifically, theorems involving fractional operators are proved. A product theorem is proved via distribution theory and a simplified proof of the real convolution theorem is given.

ISSN:0020-7721    

DOI:10.1080/00207727608941942

出版商:Taylor & Francis Group    

年代:1976

数据来源: Taylor