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Abstract: This paper presents the analysis of delay-dependent bounded input bounded output (BIBO) stability for a class of switched uncertain neutral systems. The uncertainty is assumed to be of structured linear fractional form which includes the norm-bounded uncertainty as a special case. First, by introducing the general variation-of-constants formula of neutral systems with perturbation, the BIBO stability property of general linear switched neutral systems with perturbation is established. Next, combining the general variation-of-constants formula with the state-dependent switching rule, new approaches are presented to design the feedback controller and the switching rules. Furthermore, the BIBO stability criteria are obtained in terms of the so-called Lyapunov–Metzler linear matrix inequalities (LMIs). Finally, simulation examples are given to demonstrate the effectiveness and the potential of the proposed techniques in this paper. [Copyright &y& Elsevier]

Abstract: This research deals with the utilization of analytic programming for a synthesis of control law for three selected discrete chaotic systems. The novelty of the approach is that a tool for symbolic regression–analytic programming–is used for such kinds of difficult problems. The paper consists of the descriptions of analytic programming as well as chaotic systems and used cost functions. For simulations, evolutionary algorithm SOMA (Self-Organizing Migrating Algorithm) and analytic programming were used. For each case study, repeated simulations were conducted to outline the effectiveness and robustness of used methods. All repeated simulations have given satisfactory results. [Copyright &y& Elsevier]

Abstract: Computer hardware components are susceptible to soft errors which could result in incorrect program execution with improvement of semiconductor technology. To measure the reliability of hardware components, it is important to know the effect of soft error on program outcome. This paper analyzes the effects of soft errors on the level of the program. We choose an approach which combines a high level with a low level to model the program. According to the behaviors of soft errors on hardware components during the instruction pipeline, we build a soft error model. Based on our program model and soft error model, the effect of soft errors on the whole computing program is explored from the granularity of the function. Furthermore, data flow errors and control flow errors which are two main implicit program errors caused by soft errors are analyzed respectively. Based on our analyses, we give a method to estimate the Architectural Vulnerability Factor (AVF) of hardware components statically. Our experiments illustrate this method and indicate our analysis results that there are different program behaviors under the effects of soft errors, especially the ability for the program to mask program errors which are caused by soft errors. [Copyright &y& Elsevier]

Abstract: In this paper, assuming cooperative behavior of the decision makers, solution methods for decision making problems in hierarchical organizations under fuzzy random environments are considered. To deal with the formulated two-level linear programming problems involving fuzzy random variables, -level sets of fuzzy random variables are introduced and an -stochastic two-level linear programming problem is defined for guaranteeing the degree of realization of the problem. Taking into account the vagueness of judgments of decision makers, fuzzy goals are introduced and the -stochastic two-level linear programming problem is transformed into the problem to maximize the satisfaction degree for each fuzzy goal. Through the use of the fractile criterion optimization model, the transformed stochastic two-level programming problem can be reduced to a deterministic one. Interactive fuzzy programming to obtain a satisfactory solution for the decision maker at the upper level in consideration of the cooperative relation between decision makers is presented. It is shown that all of the problems to be solved in the proposed interactive fuzzy programming can be easily solved by the simplex method, the sequential quadratic programming or the combined use of the bisection method and the sequential quadratic programming. An illustrative numerical example is provided to demonstrate the feasibility and efficiency of the proposed method. [Copyright &y& Elsevier]

Abstract: In this paper, new parametric prioritization methods (PPMs) to determine a family of priority vectors in an analytical hierarchy process (AHP) are proposed, pointing out the logical relation of elements in the comparative matrix. The scales and consistency cannot determine the priorities, but only the order of the alternatives. To derive the priorities of alternatives, a series of theorems and mathematical programming models is given based on a pairwise comparison matrix. This refers to parameters , by which there exists a family of priorities for the same judgment matrix. The discrimination of alternatives can be easily improved when using the proposed priority method by modifying the values of the parameters. Some false cognitions about how to determine the priority of an analytical hierarchy process are rectified. One should not elicit priority vectors from the judgment matrix; the information is incomplete, and the parameters must be considered. Finally, the meanings of parameters are explained in practical applications and an approach for determining the values of the parameters is proposed. Examples are also used to illustrate the features and applicability of the new approach in an AHP. [Copyright &y& Elsevier]

Abstract: The hub location problem appears in a variety of applications including airline systems, cargo delivery systems, and telecommunication network design. Hub location problems deal with finding the location of hub facilities and the allocation of demand nodes to these located hub facilities. We consider a hub-and-spoke network problem with crowdedness or congestion in the system. The transportation time and the rate of arrived trucks to each hub are random variables. In addition, a hub cannot service all trucks simultaneously and it has some restrictions like capacity constraint and the service time limitations. Hubs, which are the most crowded parts of network, are modeled as M/M/c queuing systems. In the application of the proposed model for a cargo transportation system, the number of trucks follows Poisson probability distribution in the queuing system. In this paper at first a nonlinear mathematical programming is presented to find an optimal solution for the considered problem. A probabilistic constraint is included to ensure that the probability of trucks in a queue is less than a threshold value for each hub. Then, we transfer the introduced nonlinear constraints of the mathematical programming model to the linear constraints. Due to the computational complexity of the resulted model, we propose an improved meta-heuristic based on Imperialist Competitive Algorithm and Genetic Algorithm to find near optimal solution of the problem. The performance of the solutions found by the proposed improved meta-heuristic is compared with those of pure GA and those of the mathematical programming model. [Copyright &y& Elsevier]

Abstract: Whilst few studies have explored royalty negotiations for build, operate and transfer (BOT) projects, some works have proposed numerous royalty formulas to evaluate royalty amounts or franchise fees for a BOT project. Despite this, the royalty negotiation process is one of the many critical negotiation items of a concession contract. This study not only developed a royalty negotiation model for BOT projects, but also developed the iterative algorithm for the BLP problem for the government and the private sector. In addition, the factors incorporated into the iterative algorithm for the BLP problem include the concession rate, learning rate, and the time value discount rate for both parties. Moreover, this paper conducted a case study of the Taipei Port Container Logistic BOT Project using LINGO and MATLAB programming. The results show that the two parties involved completed royalty negotiation at the sixth negotiation. The objective function value for lower-level programming was 1.062 and the government finance recovery rate for higher-level programming was 11.832. The findings show that the government can receive the royalty, which is calculated by using 0.012% of the operating revenue of this BOT project, from the concessionaire. Therefore, the royalty negotiation model based on the operating revenue developed herein; could be employed to explain the negotiation behavior. [Copyright &y& Elsevier]

Abstract: The zeroth-order general Randić index of a (molecular) graph is defined as , where is the degree of vertex in , and is an arbitrary real number. In this paper, we investigate the zeroth-order general Randić index of conjugated bicyclic graphs (i.e., bicyclic graphs with perfect matchings). We characterized the conjugated bicyclic graphs with maximum and minimum according to in different intervals. [Copyright &y& Elsevier]

Abstract: A general framework of fuzzy random chance maximization multiobjective programming is considered in this paper. The crisp counterpart model is presented for the fuzzy random chance maximization multiobjective linear programming with L-R type fuzzy random coefficients. Fuzzy random simulation is adopted to handle general fuzzy random objective functions and fuzzy random chance constraints which are usually hard to be converted into their crisp equivalents. Combining with fuzzy random simulation and the compromise approach-based genetic algorithm, we design a hybrid intelligent algorithm to solve the general fuzzy random chance maximization multiobjective programming problem. Finally, two numerical examples are presented to illustrate the effectiveness of the proposed algorithms. [Copyright &y& Elsevier]

Abstract: This paper presents a new multi-objective fuzzy mathematical model for the cellular manufacturing system (CMS) design and its solution methodology. The aim of the proposed model is to handle two important problems of CMS design called cell formation and exceptional elements simultaneously in fuzzy environment. The objective functions of the model are minimization of the cost of exceptional element elimination, minimization of the number of outer cell operations and maximization of the utilized machine capacity. The fuzziness stems from model parameters which are part demand, machine capacity and the exceptional elements’ elimination costs. To illustrate the model, an example problem with fuzzy extension is adopted from literature and computational results are obtained by using the two-phased solution procedure proposed by Arıkan and Güngör [F. Arıkan, Z. Güngör, A two-phased approach for multi-objective programming problems with fuzzy coefficients, Information Science 177 (2007), 5191–5202]. The approach is performed to reach simultaneous optimal solutions for all objective functions. The model solutions are investigated by using well-known performance measures and also three problem-specific performance measures are proposed. The model is capable of expressing vagueness of all the system parameters and gives the decision-maker (DM) alternative decision plans for different grades of precision. [Copyright &y& Elsevier]

Abstract: The emphasis of this paper is to introduce two kinds of random rough variables. One is the discrete random rough variable, the other is the continuous random rough variable. The expected value model with random rough coefficients is proposed and some special models are discussed. In order to compute the expected value of some complicated functions, the technique of the random rough simulation is presented. Combined with genetic algorithm, it is applied to check the objective function and constraint function, and to obtain the optimal solution. Finally, some numerical examples are provided to show the effectiveness of the proposed technique. [Copyright &y& Elsevier]

Abstract: With the economy continually moving towards retail and services, the size of the part-time workforce is increasing constantly. In this paper, we consider the problem of scheduling a workforce consisting entirely of part-time workers. The part-time workers have availabilities, preferences for the shifts, and also a seniority level. We propose an integer programming model to maximize employee satisfaction and to meet the demand requirements for each shift. The model is tested on randomly generated instances. The results demonstrate the effectiveness of branch-and-cut methods in reducing computation time. [Copyright &y& Elsevier]

Abstract: In this paper, stability criteria of impulsive switched systems with time-invariant delays are introduced. We proposed a class of impulsive switched systems with time delays and parameter uncertainties. Based on the result of Theorem 3.1 in [X.Z. Liu, G. Ballinger, Uniform asymptotic stability of impulsive delay differential equations, Computer and Mathematics with Applications 41 (2001) 903–915], sufficient stability conditions of the impulsive delay switched systems are obtained. The validity of the results is shown by an example and its simulation. [Copyright &y& Elsevier]