摘要:

AbstractThis paper focuses on the numerical simulation of no-load and short circuit tests in order to estimate parameters of the conventional induction motor equivalent circuit. The proposed model is based on a 2D finite element magnetic field analysis. Particular attention is devoted to the choice of the most suitable simplifying assumptions, also evaluating their influence on the result accuracy. In no-load simulation the current density is imposed and the rotor is kept in a fixed position; magnetizing inductances and iron loss resistances are evaluated. In short circuit test conditions a voltage-driven formulation, including slcin effects, is employed. Leakage inductances and rotor resistances are deduced; after the field solution, 3D effects are taken into account using classical correction factors. The computation technique is applied to several squirrel cage induction motors, and a satisfactory agreement with the measures is found.

ISSN:0228-6203    

DOI:10.1080/02286203.1995.11760250

出版商:Taylor&Francis    

年代:1995

数据来源: Taylor

摘要:

AbstractA real-time database system (RTDBS) is designed to provide timely response to the transactions of data-intensive appHcations. Each transaction processed in an RTDBS is associated with a timing constraint in the form of a deadline. Efficient transaction-scheduling algorithms are required to minimize the number of missed transaction deadlines. In this paper a performance evaluation model is provided to enable distributed RTDBS designers to analyze transaction scheduUng algorithms. The model is developed progressing from a simple mathematical analysis to compHcated simulations. The performance is expressed in terms of the fraction of satisfied transaction deadlines. The paper also provides an example simulation experiment implemented using the model prescnted.

ISSN:0228-6203    

DOI:10.1080/02286203.1995.11760251

出版商:Taylor&Francis    

年代:1995

数据来源: Taylor

摘要:

AbstractThe performance of an assembly line can be improved by deliberately unbalancing it under certain conditions. Two types of unbalanced lines, bowl versus inverted bowl line arrangements, have been assessed in previous studies, which assumed either no buffer stocks or infinite buffer stocb between any pair of work stations. Obviously, these assumptions are unrealistic. In this paper the buffer effects on the perfonnanae of bowl versus inverted bowl line arrangements are evaluated through a new simulation model Cor a hypothetical assembly line with a certain buffer capacity. The results of the simulation show that buffer capacity has significant influence on the performance oC both bowl and inverted bowl assembly lines in tenns of the total elapsed time to complete certain productions. It is found that bowl is superior to inverted bowl only when 10 or fewer buffer stocles are allowed, whereas inverted bowl is superior to bowl in cases where more buffer stocks are applied.

ISSN:0228-6203    

DOI:10.1080/02286203.1995.11760252

出版商:Taylor&Francis    

年代:1995

数据来源: Taylor

摘要:

AbstractThis paper presents an enhanced reliability modelling and evalua.tion methodology using discrete-event simulation techniques. The proposed simulation methodology has the capability of estimating reliability, mean time to failure. and probability density function of time to failure for a complex network system. Two types of reliability simulation models are presented: a descriptive network simula.tion model and a direct Markov simulation model. Both models are capable of solving complex systems consisting of components with general failure rates. The discrete-event reliability models require only descriptive knowledge of network configuration rather than analytical network characteristics, such as cuts and ties. Examples are given to demonstrate the accuracy, computational ease, and relia.bility analysis capability of these models. SIMAN is the simulation language used for both reliability modelling and evaluation. The reliability modelling technique applied through discrete-event sjmulation is modular, thus increasing its adaptability to any large-scale complex network system.

ISSN:0228-6203    

DOI:10.1080/02286203.1995.11760253

出版商:Taylor&Francis    

年代:1995

数据来源: Taylor

摘要:

AbstractThis paper proposes a study of the numerical control of multivariable systems in real time by first defining a control structure based on BellmAn theory And then developing a real-time multi-tasking environment to be used on a simulated continous multiple variable process (MIMO). The proposed solution is a control with An internal model of the process, with a model of reference“asserviasement”And a model of reference in regulation.

ISSN:0228-6203    

DOI:10.1080/02286203.1995.11760254

出版商:Taylor&Francis    

年代:1995

数据来源: Taylor

摘要:

AbstractA method of numerical control Cor multivariables systems based on reference model with respect to real time is proposed. Application of the linear sliding horizon structure/permits advance evaluation of precision and computing efficiency.

ISSN:0228-6203    

DOI:10.1080/02286203.1995.11760255

出版商:Taylor&Francis    

年代:1995

数据来源: Taylor