In this paper, we consider a queueing model for machine repairing system with Bernoulli vacation schedule. The failure times, repair times and vacation times are all assumed to be exponentially distributed. In congestion, the server may increase the repair rate with pressure coefficient  to reduce the queue length. We assume that the server begins the working vacation when the system is empty....

This paper analyzes a controllable discrete-time machine repair problem withL operating machines and two repairmen. The number of working servers can be adjusteddepending on the number of failed machines in the system one at a time at machine's failure orat service completion epochs. Analytical closed-form solutions of the stationary probabilities ofthe number of failed machines in the system a...

In this paper we consider closed loop two-echelon repairable item systems with repair facilities both at a number of local service centers (called bases) and at a central location (the depot). The goal of the system is to maintain a number of production facilities (one at each base) in optimal operational condition. Each production facility consists of a number of identical machines which may f...

This paper investigates the role of reliability parameter of the imperfect production system with random machine breakdown and stochastic repair time. Here I assume that shifting time of the production system from ‘in-control state’ to ‘out-control state’ and the time of machine breakdown are both random. Moreover, the machine repair time is stochastic and independent of the machine break-down ...

Earth pressure balance tunnel boring machines (EPB-TBMs) are favorably applied in urban tunneling projects. Despite their numerous advantages, considerable delays and high maintenance cost are the main disadvantages these machines suffer from. Reliability, availability, and maintainability (RAM) analysis is a practical technique that uses failure and repair dataset obtained over a reasonable ti...

earth pressure balance tunnel boring machines (epb-tbms) are favorably applied in urban tunneling projects. despite their numerous advantages, considerable delays and high maintenance cost are the main disadvantages these machines suffer from. reliability, availability, and maintainability (ram) analysis is a practical technique that uses failure and repair dataset obtained over a reasonable ti...

Machine repair models play an important role in many applications including computer systems, maintenance operations, and manufacturing systems. In this paper the machine repair model was adapted to describe, analyze, and simulate an agricultural application: the bin loading process during manual harvest of two specialty crops – grapes in Greece and sweet cherries in USA. In addition, a managem...

In this paper, we treat an optimal control problem of a stochastic two-machine owshop with machines subject to random breakdown and repair. While the problem is diicult to solve, it can be approximated by a deterministic problem when the rates of machine failure and repair become large. Furthermore, beginning with the solution of the deterministic problem, we can construct a feedback control fo...