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All the available knowledge related to the Fuzzy Sets (FS) is constricted to express the circumstances when the sum of the degrees of membership and non-membership of any element exceeds one. To keep in mind that in real life there are many ill-defined or too inordinately complex situations, in this article, we propose the concept of Hesitant Bifuzzy Set (HBFS), which appraises Fuzzy Set (FS), Intuitionistic Fuzzy Sets (IFS), Hesitant Fuzzy Set (HFS), Conflicting Bifuzzy Set (CBFS) and Dual Hesitant Fuzzy Set (DHFS) as particular cases. Here we discuss the fundamental operations along with the basic properties of HBFSs. A descriptive example is used to illustrate the proposed concept and method. The supremacy of this study is that all the existing methods only provide the reliability of the system in the form of a fuzzy element while the method introduced in this study always provides a crisp value for the reliability of the system. [ABSTRACT FROM AUTHOR]

Research has revealed the existence of widespread misinformation and lack of knowledge about EFT among business and government as well as consumers. As a result, any effort to stimulate meaningful public participation in decisions on the introduction of EFT systems will require a coordinated educational effort of considerable scale in addition, research has revealed shortcomings in the present system for defining responsibilities, liabilities, and avenues of recourse. This article presents several possible alternatives for improving the current system, but ongoing research is also needed to assure that actions taken will be responsive to the changing environment and consumer needs. [ABSTRACT FROM AUTHOR]

• Multi-objective reliability and cost optimization of fuel cell vehicle is addressed. • Fuzzy feasibilities in increasing the reliability of the subsystems are considered. • Two defuzzification procedures are used. • Non-dominated sorting genetic algorithm II (NSGA-II) is used with penalty functions to solve the problem. • Fuzzy decision method is adopted to find the best compromise solution. Fuel cell vehicles (FCVs) are among the so-called green vehicles. They offer high autonomy and fast refueling but are more expensive than other green vehicles. Several efforts are devoted to reducing costs to make FCV technology more accessible. Most research addressing the optimization of FCVs focuses on energy management, sizing of the subsystems, and cost. However, reducing cost conflicts with increasing reliability. This paper addresses the multi-objective reliability and cost optimization of FCVs. Due to inherent uncertainties, this work treats the feasibility of increasing the reliability of the subsystems as fuzzy values and introduces two defuzzification procedures to convert fuzzy values to crisp values, namely the ranking function and the graded mean integration value procedures. The non-dominated sorting genetic algorithm II (NSGA-II) is used with penalty functions to generate the Pareto fronts; then, a fuzzy decision method is adopted to find the best compromise solution. A numerical application of the proposed approach is illustrated. The results obtained show that the graded mean integration value procedure provides superior outcomes. The optimal reliability allocation of the subsystems in the FCV is determined. [ABSTRACT FROM AUTHOR]

The ever-increasing complexity of industry facilities has made the reliability analysis and assessment an imperative yet tough work. Motivated by practical engineering requirement, this paper develops a Bayesian-based information extraction and aggregation (BIEA) approach for system level reliability estimation of a complex system. It takes both subjective judgments and objective field outputs into consideration. Novel features of this approach Is a unique information content based aggregation process, which allows a flexible application of this framework in separated modules on account for purpose. The coherency of which is guaranteed by the objective information content calculation. This work goes beyond the alternatives that deal with solely attributed data under ideal information circumstance, and investigates a more generic tool for real engineering application. Limitations embedded in traditional statistical modeling methods have been eliminated in a nature manner by information transition and integration. In addition, a double axis driving mechanism (DADM) for erecting the antenna of a satellite Is demonstrated as case study for benefit illustration and effectiveness verification. [ABSTRACT FROM AUTHOR]

An imprecise Bayesian nonparametric approach to system reliability with multiple types of components is developed. This allows modelling partial or imperfect prior knowledge on component failure distributions in a flexible way through bounds on the functioning probability. Given component level test data these bounds are propagated to bounds on the posterior predictive distribution for the functioning probability of a new system containing components exchangeable with those used in testing. The method further enables identification of prior–data conflict at the system level based on component level test data. New results on first-order stochastic dominance for the Beta-Binomial distribution make the technique computationally tractable. Our methodological contributions can be immediately used in applications by reliability practitioners as we provide easy to use software tools. [ABSTRACT FROM AUTHOR]

Crystal oscillators are widely used in electronic systems to provide reference timing signals. Even though they are designed to be highly stable, their performance can be deteriorated by several types of random noise sources and deterministic interferences. This paper investigates the phenomenon of timing jitter in crystal oscillators induced by the injection of deterministic interferences. It is shown that timing jitter is closely related to the phase and amplitude modulations of the oscillator response. A closed-form variational macromodel is proposed to quantify timing jitter as well as to qualitatively explain the interference mechanism. Analytical results and efficient numerical simulations are developed to explore how timing jitter depends on the frequency of the interfering signal. The methodology is tested by a crystal Pierce oscillator. [ABSTRACT FROM AUTHOR]

Abstract: In the past, the main concerns for competitive enterprise environment of computer networks were data transmission delays and costs. However, from the viewpoint of quality of service (QoS), internet service providers and enterprise customers are increasingly focusing on data accuracy during transmission. This study extends a stochastic computer network (SCN) to evaluate the system reliability, where the system reliability is the probability that demand can be transmitted through the SCN under the total accuracy rate. In such an SCN, each arc has several capacities, and an accuracy rate. We can regard the system reliability as a measurable index for assessing the SCN performance. A lower boundary point for (d, K) is a minimal capacity vector, which allows the system to transmit demand d under the total accuracy rate K. Using the minimal paths, we propose an efficient algorithm to find all lower boundary points for (d, K). The system reliability can then be computed in terms of all lower boundary points for (d, K) by the recursive sum of disjoint products (RSDP) algorithm. Several numerical examples are demonstrated to illustrate the utility, efficiency, and effectiveness of the proposed algorithm. [Copyright &y& Elsevier]

Abstract: The minimum and maximum distances denoting the extreme numbers of successes between two successive failures in binary sequences, are considered. Exact marginal and joint probability distributions of these statistics are obtained via combinatorial analysis. Applications related to urn models and system reliability are studied and clarify further the theoretical results. [ABSTRACT FROM AUTHOR]

Abstract: It is often necessary to conduct individual component tests for the prediction and verification of system reliability. Moreover, system testing can be economically infeasible or even impossible. The question then arises as to how component test plans should be designed so as to minimize test costs. Acceptance procedures based on the sum of failures during component tests have been previously suggested in the literature only for a series system, parallel system, and a serial connection of redundant subsystems. This line of research is extended by considering serial connection of standby redundant and k-out-of-n subsystems. It is shown that the serial connection of the mixture of all these systems can also be modelled. The optimal component testing problem is formulated as a semi-infinite linear program, and a procedure to compute optimum component test times is developed. The solution procedure is based on the well known cutting plane idea and column generation technique. Numerical examples are also provided. [Copyright &y& Elsevier]