We consider multicomponent maintenance systems with an F -failure group age-replacement policy: it keeps failed components idling until F components are failed and then replaces all failed components together with the nonfailed components whose age has passed the critical threshold age n for components of type n. With each maintenance action, costs are associated. We derive various unbiased gra...

Anew algorithm is proposed for the numerical solution of threshold problems in epidemics and population dynamics. These problems aremodeled by the delay-differential equations, where the delay function is unknown and has to be determined from the threshold conditions. The new algorithm is based on embedded pair of continuous Runge–Kutta method of order p = 4 and discrete Runge–Kutta method of o...

Tackling new machine learning problems with neural networks always means optimizing numerous hyperparameters that define their structure and strongly impact performances. In this work, we study the use of goal-oriented sensitivity analysis, based on Hilbert–Schmidt independence criterion (HSIC), for hyperparameter analysis optimization. Hyperparameters live in spaces are often complex awkward. ...

This paper investigates the optimal refilling policy for an economic production quantity (EPQ) model with rework and breakdown taking place in backorder replenishing time. A recent published article [Chiu, Y.P., 2003. Determining the optimal lot size for the finite production model with random defective rate, the rework process, and backlogging. Engineering Optimization 35, 427-437] has studied...

Repairable systems are either repaired perfectly to a state of as good as new or imperfectly. In this work, a system which undergoes imperfect repair is investigated. A nonlinear mathematical model is formulated for a system with the objective of finding the optimum failure and repair rate with the minimum costs subject to attaining a pre-specified performance level. Two imperfect repair models...

in this paper, a method based on binary-coded genetic algorithm is proposed to explore an optimization method, for obtaining an optimal elliptical tank. this optimization method enhances the rollover threshold of a tank vehicle, especially under partial filling conditions. minimizing the overturning moment imposed on the vehicle due to c.g. height of the liquid load, lateral acceleration and ca...

In this paper, a dynamic preventive maintenance strategy is proposed for the problem of high cost rate due to excessive caused by unreasonable threshold setting when complex electromechanical equipment formulated. Increasing failure factor and decreasing service age are introduced describe evolution rules during coating machine, BP-LSTM (BP-Long Short Term Memory Network, BP-LSTM) model combine...

An M x /G/1 queueing system with second optional service (SOS)is studied under N policy and Bernoulli Vacation. The system remains idle until the queue size reaches or exceeds N ( ≥ 1). When the queue size reaches at leastN, the server may begin his setup operation with probability s or may start the service with probability (1-s). The server provides two phases of heterogeneous services, of wh...

In a Cloud computing environment, the workload fluctuates dynamically producing undesirable situations such as load imbalance, lower utilization or workload hotspots. In such cases, virtual machine migration is a potential solution. However, an algorithm based on a single objective (e.g. service-level agreement) is usually used to direct the migration process. On the contrary, there exist uncon...

Motivated by the urgent demand for the electric vehicle (EV) fast refueling technologies, battery swapping and charging stations (BSCSs) are envisioned as a promising solution to provide timely EV refueling services. However, inappropriate battery charging operation in BSCSs can not only incur unnecessary high charging cost but also threaten the reliability of the power grid. In this paper, we ...