Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8651
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Conference Object Citation - Scopus: 12Computation of Supervisors for Fault-Recovery and Repair for Discrete Event Systems(IFAC Secretariat, 2014) Sülek, A.N.; Schmidt, K.W.In this paper, we study the fault-recovery and repair of discrete event systems (DES). To this end, we first develop a new method for the fault-recovery of DES. In particular, we compute a fault-recovery supervisor that follows the specified nominal system behavior until a fault-occurrence, that continues its operation according to a degraded specification after a fault and that finally converges to a desired behavior after fault. We next show that our method is also applicable to system repair and we propose an iterative procedure that determines a supervisor for an arbitrary number of fault occurrences and system repairs. We demonstrate our method with a manufacturing system example. © 2021 Elsevier B.V., All rights reserved.Conference Object Nonconservative Systems Within Fractional Generalized Derivatives(IFAC Secretariat, 2006) Baleanu, D.; Muslih, S.I.Fractional calculus is a promising tool for investigation of both conservative and non-conservative systems. Fractional Hamiltonian formulation represents an important problem of the fractional quantization. In this paper the nonconservative Lagrangian mechanics is investigated within fractional generalized derivative approach.Conference Object Strategy Creation, Decomposition and Distribution in Particle Navigation: Memory Module(IFAC Secretariat, 2005) Beldek, U.; Leblebicioglu, K.in particle navigation problem strategy development is crucial. The difficulties encountered by the particles during their navigation tasks require different approaches in problem solving. One way to overcome the difficulties is to divide the problem into simple modules and develop solutions for these modules separately. Basically, two different modules are sufficient in addition to the main body to develop a successful solver. The first module (conflict module), which is developed by genetic programming, is used when the particles are in conflict. The second module (memory module) helps the particles to escape from local regions. Copyright © 2005 IFAC.Conference Object Citation - Scopus: 11Computation of Supervisors for Reconfigurable Machine Tools(IFAC Secretariat, 2012) Schmidt, K.W.The rapid reconfiguration of manufacturing systems is an important issue in today's manufacturing technology in order to adjust the production to varying product demands and types. In this paper, we study the control of reconfigurable machine tools (RMTs) with the aim of fast reconfiguration and an easy controller implementation. We first formulate a particular reconfiguration problem for RMTs in a discrete event system setting, and then provide necessary and sufficient conditions for its solution. Moreover, we propose an algorithm for the construction of a reconfiguration supervisor as the composition of one supervisor for each separate RMT configuration and one supervisor that performs the transition between configurations. The reconfiguration supervisor can be computed in polynomial time, and allows configuration changes within a bounded delay. In addition, our method facilitates the addition of a new configuration during system operation.Conference Object Path Integral Quantization of Brownian Motion as Mechanical Systems With Fractional Derivatives(IFAC Secretariat, 2006) Rabei, E.M.; Baleanu, D.; Muslih, S.I.In this paper, the mechanical systems with fractional derivatives are studied by using fractional formalism. The path integral quantization of these system is constructed as an integration over the canonical phase space. The path integral quantization of a system with Brownian motion is carried out. Copyright 2006 IFAC.Conference Object Citation - Scopus: 1Local Decision-Making in Multiple Levels for Lottery Data Analysis(IFAC Secretariat, 2011) Leblebicioǧlu, K.; Beldek, U.Sales forecasting is a common problem in economics. Lottery sales are one of the favorite issues of sales forecasting. Sales of lottery tickets depend on many economical issues and such a problem was investigated previously (Beensock et al., 2002) where Genetic Programming is used in order to construct different agent structures that predict the number of ticket sales in Israel lottery. In each application in (Beensock et al., 2002), only a single agent is developed to predict the number of ticket sales at a present drawing. Instead we propose a Local Decision-Making model which performs the sales forecasting job in multiple levels by employing agent structures that operate locally and combine their decisions via a suitable decision fusion technique. It seems that Local Decision-Making in Multiple Levels fits well for the problem. © 2011 IFAC.Conference Object Hierarchical Multitasking Control of Discrete Event Systems: Computation of Projections and Maximal Permissiveness(IFAC Secretariat, 2010) Cury, J.E.R.; Schmidt, K.; De Queiroz, M.H.This paper extends previous results on the hierarchical and decentralized control of multitasking discrete event systems (MTDES). Colored observers, a generalization of the observer property, together with local control consistency, allow to derive sufficient conditions for synthesizing modular and hierarchical control that are both strongly nonblocking (SNB) and maximally permissive. A polynomial procedure to verify if a projection fulfills the above properties is proposed and in the case they fail for a given projection an algorithm is proposed to find an extension of the set of events to be projected, in order to fulfill the sufficient conditions for SNB and maximally permissive hierarchical control.Conference Object Citation - Scopus: 6Fractional Calculus and the Schrödinger Equation(IFAC Secretariat, 2006) Baleanu, D.; Mainardi, F.; Mura, A.; Scalas, E.In this paper, a derivation of the fractional Schrödinger equation is presented for the simple case of a pure diffusive process with dissipation. The Gaussian white noise is replaced by more general kinds of white noise and both the Markovian both the Markovian (β = 1) and non-Markovian case (0 < β < 1) are considered. Copyright © 2006 IFAC.Conference Object Computation of Projections for the Abstraction-Based Diagnosability Verification(IFAC Secretariat, 2010) Schmidt, K.The verification of language-diagnosability (LD) for discrete event systems (DES) generally requires the explicit evaluation of the overall system model which is infeasible for practical systems. In order to circumvent this problem, our previous work proposes the abstraction-based LD verification using natural projections that fulfill the loop-preserving observer (LPO) property. In this paper, we develop algorithms for the verification and computation of such natural projections. We first present a polynomial-time algorithm that allows to test if a given natural projection is a loop-preserving observer. Then, we show that, in case the LPO property is violated, finding a minimal extension of the projection alphabet such that the LPO condition holds is NP-hard. Finally, we adapt a polynomial-time heuristic algorithm by Feng and Wonham for the efficient computation of loop-preserving observers.Conference Object Citation - Scopus: 8Computation of Fault-Tolerant Supervisors for Discrete Event Systems(IFAC Secretariat, 2013) Sülek, A.N.; Schmidt, K.W.Fault-tolerance addresses the problem of operating a system even in case of faults. In this paper, we study fault-tolerance in the supervisory control framework for discrete event systems (DES). We consider DES, where certain events might no longer be possible in case a fault happens. In this setting, we first identify necessary and suficient conditions for the existence of a supervisor that realizes a given behavioral specification both in the non-faulty and in the faulty case. We further show that it is possible to determine a supremal fault-tolerant sublanguage in case the existence condition is violated. Finally, we propose an algorithm for the computation of this sublanguage and prove its correctness. Different from existing work, our fault-tolerant supervisor allows fault occurrences and system repairs at any time. The concepts and results developed in this paper are illustrated by a manufacturing system example. © 2013 IFAC.