摘要:

It is shown that the matrix minimum principle can be used to study both deterministic and stochastic control systems described by partial differential equation models. It in shown that the matrix formulations of the control problem reduce to a state canonical equation which is identical with the Riccati equation of the conventional state vector representation. The technique employs the powerful optimization techniques of the calculus of variations and dynamic programming, and leads in a natural way to the separation principle for the case of stochastic optimal control problems. The results of this study show once more the close relationship between the tools used for finite-dimensional control problems and their distributed-parameter (infinite-dimensional) counterparts.

ISSN:0020-7721    

DOI:10.1080/00207728008967055

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

In this paper, s mathematical model of the nitrogen cycle in aquatic ecosystems is proposed for studying eutrophication in bodies of water. It is presented that for some parameter values all equilibrium states of the system become unstable and a stable limit cycle appears. This is explained by a Hopf bifurcation. The conditions under which the Hopf bifurcation occurs are obtained by the detailed analysis of the model. Some results of numerical computations are also presented.

ISSN:0020-7721    

DOI:10.1080/00207728008967056

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

In this paper, the class of linear multivariable continuous-time plants which ire amenable to fast-sampling error-actuated control is characterized in terms of the relatively prime polynomial matrix factors of the transfer function matrices of such plants. It is shown that this characterization greatly facilitates the design of fast-sampling error-actuated controllers, and the resulting synthesis technique is illustrated by designing such a controller for a third-order plant with two inputs and two outputs.

ISSN:0020-7721    

DOI:10.1080/00207728008967057

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

The concept of absolute tracking (Grujić and Porter 1980) is extended so as to embraco Lur´e control systems subjected to multiple immeasurable disturbances and multiple unmeasurable command inputs. It is shown that the tracking characteristics of closed-loop control systems incorporating Lur'e plants with multiple non-linearities can be established on the basis of the absolute stability characteristics of associated free systems. These general results are illustrated by synthesizing a tracking system incorporating a Lur'e plant with two non-linearities.

ISSN:0020-7721    

DOI:10.1080/00207728008967058

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

This paper considers the transformation of the optimal digital control problem to en equivalent discrete-time optimal control problem in the case of deterministic and stochastic sampling. The continuous-time system to be controlled is linear and disturbed by additive continuous-time white noise (not necessarily gaussian). The observations available at the sampling instants are in general non-linear and corrupted by discrete-time noise independent of the system noise (not necessarily additive, white or gaussian). The performance criterion is quadratic and an integral rather than a sum.

ISSN:0020-7721    

DOI:10.1080/00207728008967059

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

A previous paper was devoted to the rigorous development of an exact synthesis technique for uncertain multiple-input-output feedback systems. This paper is devoted to practical design execution, by means of two detailed 2×2 examples with large plant parameter uncertainty. The outstanding features are : (1) The problem muat be quantitative. Performance bounds must be assigned to the matrix of closed-loop. transfer functions, and the parameter uncertainty sets defined. (2) The design problem is translated into separate quantitative single-loop systems such with i1« own sets of parameter uncertainty, disturbances and performance tolerances. The solutions (compensation functions) for the single-loop problems are guaranteed to solve the multiple-input-output problem. There is no need to consider the characteristic equation of the latter or any of its other system functions. (3) There is considerable design transparency. As he proceeds, the designer can see the trade-offs between the loops, and may, if desirable, sacrifice one for the other. Also he may modify the original performance tolerances, without violating them, so as to economize on the compensation function band widths. (4) The design is tuned to the problem. The larger the uncertainty and the more narrow the tolerances, the larger the required compensation bandwidths. In the case of no uncertainty, the design emerges with no need for feedback at all.

ISSN:0020-7721    

DOI:10.1080/00207728008967060

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

A recursive estimation technique is applied to the noisy image which is represented by a hyperbolic partial differential equation (PDE). Approximating a PDE model by a finite-difference approximation leads to an autoregressive (AR) model representation which Jain pointed out. In this paper, we use a new PDE model for the image representation. To apply a recursive estimation scheme to the image which is degraded by white noise, we propose the transformation of the.AR model into a state-space representation. To this representation, we apply a Kalman strip processor to reduce the order of the computation and storage, and the strip smoother (the optimal fixed-interval smoother) is also applied to obtain a better estimated imago. Three numerical examples are illustrated to show the effectiveness of the proposed algorithm.

ISSN:0020-7721    

DOI:10.1080/00207728008967061

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor

摘要:

In thia paper the plan of allocating total investment between the agricultural and the industrial sectors in India is analysed in the framework of an optimal control system. A method of optimal control using the generalized (pseudo) inverse is proposed. The result shows that the optimal allocation paths do not support the idea of putting more emphasis on the agricultural sector in the beginning of the development process.

ISSN:0020-7721    

DOI:10.1080/00207728008967062

出版商:Taylor & Francis Group    

年代:1980

数据来源: Taylor