In this paper an analytical approach for the reliability evaluation of complex manufacturing system is presented, where a manufacturing system is in operative state only if its production capacity requirements are satisfied. We considered a manufacturing system with three types of failures namely type I, type II and type III failures. The proposed system works in four modes: normal, degraded, d...

In this paper we study a queueing system with state-dependent services and state-dependent vacations, or simply G/M(n)/1/K. Since the service rate is state-dependent, this system includes G/M/c and G/M/c/K queues with various types of station vacations as special cases. We provide a recursive algorithm using the supplementary variable technique to numerically compute the stationary queue length...

Abstract: This paper presents a mathematical model for a multi-state complex repairable manufacturing system with four types of failures such as common cause, partial, human and catastrophic incorporating waiting time to repair. As regards to repairing of the system, it has to be wait for repair due to unavailability of repair facility after common cause failure. The system may also fail due to...

In this paper a stochastic model for a single unit repairable system with Preventive Maintenance (PM) under warranty is analyzed in details by using supplementary variable technique. The cost of repair during warranty is born by the manufacturers, but warranty does not apply to product failure due to user-induced damage such as cracked screen or cracked casing, accident, misuse, physical damage...

We study an M/G/1 queueing system where the arrival follows Poisson Process. The server provides service in two stages, the first stage service is essential and the second stage of service is optional. If the system is empty then the server goes for a vacation of random duration and after returning from vacation the server decides to take a second vacation which is optional. When the server is ...

Abstract. A batch arrival retrial queue with general retrial times, state dependent admission, modified vacation policy and feed back is analysed in this paper. Arrivals are controlled according to the state of the server. If the orbit is empty, the server takes at most J vacations until at least one customer is received in the orbit when the server returns from the vacation. At the service com...

The decades-long use of supplementary cementitious materials (SCMs) as replacements for ordinary Portland cement (OPC) by the and concrete industry is undergoing a resurgence in research activities related to goals addressing circular economy activities, well reduction CO2 emissions. Differences chemistry, mineralogy reactivity SCMs compared OPC impact fresh properties concrete. Some exhibit gr...

SUMMARY The fundamental problem of gene selection via cDNA data is to identify which genes are differentially expressed across different kinds of tissue samples (e.g. normal and cancer). cDNA data contain large number of variables (genes) and usually the sample size is relatively small so the selection process can be unstable. Therefore, models which incorporate sparsity in terms of variables (...

This paper considers a repairable system with a repairman, who can take multiple vacations. If the system fails and the repairman is on vacation, it will wait for repair until the repairman is available. Assume that the system cannot be repaired ‘‘as good as new’’ after failures. Under these assumptions, using the geometric process and the supplementary variable technique, some important reliab...