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Abstract: The many types of public sheet-handling machines must handle sheets (e.g. tickets, sheet of paper) under various conditions at high speed. It is therefore necessary to understand the sheet’s behavior in order to avoid problems associated with handling it. This paper develops a nonlinear simulation that determines the behavior of a sheet handled in a machine. The simulation is based on a discretized model of the sheet using lumped masses and springs. The simulation results are validated with experimental data from a sheet-handling machine fed with various types of sheets. The experimental results agree well with simulation, showing that this method is useful and practical to predict the behavior of flexible sheets handling in a feeding machine. [Copyright &y& Elsevier]

Highlights: [•] A novel learning-based harmony search (HS) algorithm is proposed in this paper. [•] Learning automata is employed for fine-tuning of HS parameters. [•] No parameter-setting is required in the proposed learning automata based harmony search algorithm. [•] The numerical results indicate that the proposed algorithm outperforms the other HS variants. [ABSTRACT FROM AUTHOR]

Abstract: High-level descriptions of real-time systems often use fuzzy notions of time that are left open to domain specific interpretations. In order to verify that a given implementation conforms to such loosely defined specifications, the typical approach is to verify the implementation to be correct within well defined limits of time tolerance. This approach determines whether the real-time requirements are met, but does not reflect how well it is met. Our goal in this paper is to prescribe the development of timed specifications using fuzzy notions of time, and to present a methodology for computing the quality of satisfaction of the specification on a given implementation using domain specific fuzzy membership functions. With this objective, we combine the notions of real-time interval temporal logic (like Metric Interval Temporal Logic) and fuzzy logic to derive FRTL, a fuzzy real-time temporal logic. The novelty of the proposed logic is in introducing the notion of fuzzy time intervals into the core fabric of conventional metric temporal logic. We present a method for evaluating the fuzzy truth of FRTL properties on finite traces. We discuss the motivation of computing the fuzzy truth towards evaluating the quality of control in time critical embedded control system applications. We also show that two important related problems from the domain of mixed-signal design verification, are subsumed by the proposed framework of analysis. [Copyright &y& Elsevier]

Abstract: This paper explores the simultaneous batch splitting and scheduling problem for identical parallel production lines, which is different from the parallel machine scheduling in that the processing time of a batch on parallel production lines is not fully proportional to that of a product. To solve the problem, a formula is derived to determine the processing time of a batch on a production line which is not taken as a single machine for each item in the batch. A lower bound is provided for the starting time of a batch production, which overlaps the previous one. A sufficient condition for guaranteeing the constant availability of the end buffer is given and proven mathematically with respect to a continuously delivered batch. Based on the above, an algorithm whose complexity is unrelated to the batch size is proposed to obtain the starting time of a batch production. Finally, a heuristic method based on genetic algorithm is constructed to solve the splitting and scheduling problems simultaneously. Numerical experiments show that this method functions well to balance the loads of the production lines. In fact, the proposed approach is significantly more effective than the existing methods for production planning and scheduling on production lines (each of which is considered as a single machine for both batch and item). [Copyright &y& Elsevier]

Abstract: In this paper, we investigate a time-dependent learning effect in a flowshop scheduling problem. We assume that the time-dependent learning effect of a job was a function of the total normal processing time of jobs scheduled before the job. The following objective functions are explored: the makespan, the total flowtime, the sum of weighted completion times, the sum of the kth power of completion times, and the maximum lateness. Some heuristic algorithms with worst-case analysis for the objective functions are given. Moreover, a polynomial algorithm is proposed for the special case with identical processing time on each machine and that with an increasing series of dominating machines, respectively. Finally, the computational results to evaluate the performance of the heuristics are provided. [Copyright &y& Elsevier]

Abstract: Model checkers for systems represented by labelled transition systems are not as extensively used as those for systems represented by Kripke structures. This is partially due to the lack of an elegant formal language for property specification which would not be as raw as, for example, HML yet also not as complex as, for example, -calculus. This paper proposes a new action-based propositional branching-time temporal logic ACTLW, which enhances popular computation tree logic (CTL) with the notion of actions in a similar but more comprehensive way than action-based CTL introduced by De Nicola and Vaandrager [R. De Nicola, F.W. Vaandrager, Action versus logics for transition systems, in: Semantics of Systems of Concurrent Processes, Proceedings LITP Spring School on Theoretical Computer Science, LNCS 469, 1990, pp. 407–419]. ACTLW is defined by using temporal operators until and unless only, whereas all other temporal operators are derived from them. Fixed-point characterisation of the operators together with symbolic algorithms for global model checking are shown. Usage of this new logic is illustrated by an example of verification of mutual-exclusion algorithms. [Copyright &y& Elsevier]

Abstract: Vorticity confinement methods have been shown to be very effective in the computation of flows involving the convection of thin vortical layers. These are the only Eulerian methods whereby simulations of these layers remain very thin and persist long distances without significant dissipation. Initially developed by Steinhoff and co-workers for incompressible flow, these methods have been used successfully to predict complex flows, particularly involving helicopter rotors. Recently, the method has been extended to a compressible finite-volume form, which will enable the methods to be used for a much broader class of problems. In this paper, we examine the ability of the compressible vortex confinement methodology to handle an important class of vortex-dominated flows involving massive separation from bluff bodies. We evaluate the effectiveness of the method by comparisons with experimental data and available state-of-the-art computations. An important conclusion of the present work is that vortex confinement applied to massively separated flows, without modeling the viscous terms and on an essentially inviscid grid, can result in a reasonable approximation to turbulent separated flows. The computed flow structures and velocity profiles were in good agreement with time-averaged values of the data and with LES simulations even though the confinement approach utilized more than a factor of 50 fewer cells in the computation (20,000 compare to more the 1 million). The success of the method for these classes of flows may be attributed to the accurate calculation of the rotational inviscid flow which dominates the convection of the large-scale flow structures. [Copyright &y& Elsevier]