This paper reports on the application of the sequential method, presented in a previous paper by Lai et al. in 2001, to determine optimal strategies of when to carry out a preventive maintenance action for an engine and when to replace an engine in use. The sequential method was run with real...

In this paper, we consider the pair of symmetric dual multiobjective variational mixed integer programs proposed by Chen and Yang [X. Chen, J. Yang, Symmetric duality for minimax multiobjective variational mixed integer programming problems with partial-invexity, European Journal of Operational...

This study presents several revenue optimisation models for hotel room reservations for a future target day with multiple-day stays. Assume that the hotel has only one type of room but the unit rate for the room may be different during every booking period and every reservation may cover several...

In this study, we employed a geometric process approach to resolve gearbox maintenance problems. The approach is realistic and direct in modelling the characteristics of a deteriorating system such as a gearbox since a decreasing geometric process can model a gearbox’s successive operating...

In this study, a power law process (PLP) for the failures of an engine, regarded as a complex repairable system, in a minimal repair set‐up (i.e. only a small proportion of the constituent parts of the engine are replaced on repair) with the engine regularly replaced within period T or...

The multilevel impurity photovoltaic effect (IPV) of the sulfur doped crystalline silicon (c-Si) is studied by using the SCAPS program. The effects of impurity concentration (Nt) of two and four defect levels on the performance of sulfur doping c-Si solar cell are investigated, respectively....