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FUNDAMENTAL PROPERTY SHIFTS IN MIMO V-INTERCONNECTED SYSTEMS FOR CONTROL AND DIAGNOSTICS A. T. Tzanev Key Words MIMO systems; interconnections; system property changes; interaction coefficient; diagnostic symptoms Abstract Theoretically inherent properties in the class of MIMO V-interconnected systems incline options for arising arbitrary shifts in their fundamental properties, thus demonstrating full-scale plant behaviors when running in a large process range. This curious effect leads to far more serious functional changes in the process properties from mere plant parameter variations. The phenomenon is commented occasionally by some authors in somewhat empirical forms, but nevertheless, it is not yet comprehensively examined in the light of the aggravating subsequences to the control efforts and the task of efficient process diagnostics to that class of plants. Article PDF Download article (PDF)

COMPUTER SIMULATIONS FOR STABILITY ANALYSIS OF A NUMERICAL PROCEDURE FOR CROSSBAR PACKET SWITCH T. Tashev, V. Monov, R. Tasheva Key Words Computer technologies; simulations; generalized nets; numerical methods; crossbar switch. Abstract The paper is concerned with the problem of calculating the bound of the throughput (THR) of a crossbar packet switch. For this purpose a suitable numerical procedure is used. The input data for the procedure are the results of computer simulations executed on a grid-computational structure (www.hpc.acad.bg). The modeling of the THR uses MiMa-algorithm for a crossbar packet switch, specified by the apparatus of Generalized Nets. For studying the stability of the numerical procedure we use a modified family of patterns for i.i.d. Bernoulli uniform load traffic simulation. The obtained results show that the numerical procedure is stable which means that small input perturbations result in small changes in the output. Article PDF Download article (PDF)

METHODOLOGY FOR TESTING OF A DRIVE SYSTEM WITH REMOTE MONITORING AND CONTROL V. Dimitrov Key Words Remote monitoring and control; intelligent energy meter; asynchronous drive; soft starter; programmable logic controller PLC. Abstract A laboratory drive system with remote monitoring and control has been designed and built. An asynchronous motor controlled by a soft starter and remote monitoring and control by contemporary devices has been provided. This laboratory system is used for research and in teaching. In this paper, methodology of tests is developed. Some examinations are presented. Thus an experimental verification of the developed methodology is carried out. Systems for remote monitoring and control on energy consumption, efficiency and proper operation of the controlled objects are very often used in different spheres of industry, building automation, transport, electricity distribution network, etc. The optimal solution for each particular case could be achieved but a complex research and testing have to be previously performed using the developed methodology Article PDF Download article (PDF)

AN ALGORITHM FOR GENERATING A DISPERSED POPULATION OF FEASIBLE SCHEDULES FOR FLEXIBLE JOB SHOP PROBLEMS L. Kirilov, V. Guliashki Key Words Flexible job shop problems (FJSP); scheduling; heuristics; optimization Abstract The flexible job shop problems (FJSP) are an important class of scheduling problems and they have a significant practical value. Unfortunately it is not easy to solve job shop problems and in particular FJSPs because they are NP-hard problems. In this paper we propose a method for generating a set of feasible schedules for a given FJSP Article PDF Download article (PDF)

QUICK IMPLEMENTATION OF DEFINITE INTEGRALS COMPUTATION WITH VERY HIGH PRECISION V. Dzhambov Key Words High precision computation; parallel computations; numerical quadrature; computational mathematics; .NET Framework; X-MPIR. Abstract An exceptionally effective implementation using parallel computations with two perspective quadrature schemes in a specific environment, namely .NET Framework, is discussed. Comparative tests are carried out demonstrating the possibility for effective computations with very high precision with specific tools of the environment being used. This paper describes a part of the research undertaken for the purpose of creating a tool library for arbitrary precision calculations [1]. The main goal is to demonstrate that very useful and mutually complementing computational tools, solving non-trivial problems with high precision computations may be implemented in a concrete environment, which is wide spread for personal computers, but underestimated by the software developers of scientific applications Article PDF Download article (PDF)