摘要:

AbstractThe following paper contrasts different modelling techniques in terms of performance, flexibility, and control. The authors discuss how a single scheduling problem, the Gate Assignment Problem, can be implemented using three different modelling techniques: an integer programming model, a discrete simulation, and an expert system. In doing so, the authors characterize some of the advantages and disadvantages of using the three different methods. The purpose of such an exercise is to develop criteria that can be used to select an appropriate solution technique for a particular problem.

ISSN:0228-6203    

DOI:10.1080/02286203.1994.11760204

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractThis paper is concerned with the development and implementation of a new gradient-based algorithm for image restoration. The algorithm assumes that the original intensity signal s(x) has been affected by a (known) linear, but not necessarily space-invariant, point spread function (PSF) h(x,u) in an additive white Gaussian noise environment. It is assumed that the covariance function of s(x) is known a priori. Based on these assumptions, the algorithm tends toward the maximum likelihood estimate of s(x) using the steepest ascent routine. It is shown that the algorithm is reduced to the least squares error (LSE) restoration scheme reported by Angel and Jain [1] in the absence of noise˙when the covariance function of s(x) is an impulse function. Simulation experiments are presented for the algorithm with actual and modeled statistics and comparisons are made with the LSE algorithm.

ISSN:0228-6203    

DOI:10.1080/02286203.1994.11760205

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractThis paper proposes a method for estimating all the model parameters for control purposes of a squirrel-cage induction motor in variable operating conditions. The estimation of parameters is based on the manipulation of the measurable quantities such as stator voltages, stator currents and shaft speed. The fundamental equations for estimaltion are derived by integrating the nonlinear rlifferential equa.tions which characterize the motor dynamics. The parameters are determined by using the data from synchronous and no-load tests of the motor at two arbitrarily different operating points. ltcsults from computer simulations demonstrate that the degree of ilccnracy of the estimation ca.n satisfy the requirements of control applications.

ISSN:0228-6203    

DOI:10.1080/02286203.1994.11760206

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractResequencing problems arise in various distributed applications in which tasks are required to respect several ordering or synchronization constraints. These phenomena are common in queuing systems with multiple parallel servers, In this context, we study the delay implied by the resequencing procedure under different types of relationships characterizing the precedence constraints among tasks.

ISSN:0228-6203    

DOI:10.1080/02286203.1994.11760207

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractThe Multiple Model Estimation Algorithm (MMEA) consists of a set of Kalman Filters and is amenable to realization by parallel processing techniques. A model-based fault diagnostic procedure utilizing an MMEA has been implemented for an eddy-current test instrument and the signal processing is based on an array of four transputers. The computational procedures are described here and results are presented.

ISSN:0228-6203    

DOI:10.1080/02286203.1994.11760208

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractThe effects of load balancing on system and program performance of a heterogeneous distributed system model are studied using simulation techniques. A closed queuing network model is considered with two independent processors, each serving its own queue. The service speed of one processor is double the service speed of the other.A probabUistic and a deterministic load baiancing policy are studied and compared in two cases. In the first case all programs are identical and can be assigned to either of the processors. In the second case, half of the programs are dedicated to the fast processor. while the rest are generic and can be individually allocated to either of the processors. It is shown that using these policies, system and program performance depend on the degree of multiprogn. mming.

ISSN:0228-6203    

DOI:10.1080/02286203.1994.11760209

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractIn this paper we develop algorithms, resting on the principle of Recursive Least-Squares, for the treatment of multichannel signals. A method of modelling in packs is presented in the scalar and vectorial cases, the latter of which takes into account the independent or dependent context of the channels. In a situation of slowly evolving signals, a detection method of model changes with two thresholds is proposed. A simulation of the presented algorithms is done on electroencephalographic signals on which our method was successfully applied to the detection of typical epileptic events.

ISSN:0228-6203    

DOI:10.1080/02286203.1994.11760210

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor

摘要:

AbstractPatients with impaired renal function often surfer undesired side- effects of drugs caused, above all, by reduced elimination of unchanged dmg and toxic metabolites as well as by diminution of the distribution volume. Plasmapheresis is one well-known treatment procf'dnre for such patif'nt.s, but may reduce drug plasma concentrations below the toxic and possibly below the therapeutic level, and therefore an optimal individual drug therapy design is needed. This work (kals with the development of a time-varying multicompartment model for the evaluation of the inflnences of plasmapheresis on drug pharmacokinetics. Analog- hybrid computer was chosen as the simulation tool. Model validation was realized by the aid of the corresponding in vivo clinical measurements and subsequent chemical analysis of the sampled biological materials. The approach is illustrated by a particular drug pharmacokinetic st.udy under the conditions of plasmnpheresis. The obtained result show the suitability of the chosen modelling techniques as well as the flexibility of the used simulation tool in designing the mentioned therapy. The approach has been already used for some problematic cases. With the use of the appropriate digital simulation language on IBM PC/AT computer, the procedure will soon become available in routinc clinical practice.

ISSN:0228-6203    

DOI:10.1080/02286203.1994.11760211

出版商:Taylor&Francis    

年代:1994

数据来源: Taylor