A series repairable system not only is one of the classical reliability models but is also the usually used model in practice. In this paper, a method for calculating system availability for series repairable system is studied. From the states of components, this methodology uses a gamma distribution to model the material degradation, and the impact of imperfect maintenance actions on the syste...

The reliability of repairable stand by systems is investigated using semi-Markov processes. The systems are composed of n units having general failure time distribution with mean 1/). and of r repair facilities having exponential repair time distribution with mean l/p. For these systems, the Laplace-Stieltjes transform (LST) of the system failure time distribution is derived in the form of a ge...

Swarming motility of Serratia liquefaciens MG1 requires the expression of two genetic loci, flhDC and swrI. Here we demonstrate that the products of the flhDC operon (the flagellar master regulator) and the swrI gene (the extracellular signal molecule N-butanoyl-L-homoserine lactone) are global regulators which control two separate regulons.

The availability equivalence factors of a general repairable parallel-series system are discussed in this paper considering the availability function of the system. The system components are assumed to be repairable and independent but not identical. The life and repair times of the system components are exponentially distributed with different parameters. Two types of availability equivalent f...

random early detection (red) is one of the most commonly used active queue management (aqm) algorithms that is recommended by ietf for deployment in the network. although red provides low average queuing delay and high throughput at the same time, but effectiveness of red is highly sensitive to the red parameters setting. as network condition varies largely, setting red's parameters with fixed ...

Existence of capacity drop phenomenon, as the difference between pre-queue and queue discharge flow rates, has been one of the controversial concepts of traffic engineering. Several researches have focused on capacity drop existence and also its estimation issues. This paper aims to estimate capacity drop based not only on a comparison between breakdown and queue discharge flow rates, but also ...

In this paper, a meta-heuristic method, the Bat Algorithm, based on the echolocation behavior of bats is used to determine the optimum service rate of a queue problem. A finite buffer M/M/1 queue with N policy, multiple working vacations and Bernoulli schedule vacation interruption is considered. Under the two customers' impatient situations, balking and reneging, the...

This paper introduces a Markov model for a multi-state repairable system in which some states are changeable in the sense that whether those states are up or down depends on the recent system evolution history. Several reliability indexes, such as availability, mean up time, steady-state reliability, are calculated using the matrix method. A sufficient condition under which the availabilities o...

This paper reports a study on a single server queue with bulk arrival and bulk service patterns wherein the incoming traffic depends on the state of the server which may be in operating or breakdown state. The repair of the breakdown server is performed in two phases. The operating duration of server, repair duration of both phases of repairing as well as job's inter-arrival times and service t...