Industrial equipment is usually repairable. Reliability of repairable systems depends on maintenance actions, and is characterized by mean cumulative function or failure intensity function of failure processes. Evolution trend of the failure intensity function is called the system-level failure pattern in the literature. The failure pattern plays an important role in preventive maintenance deci...

In this paper we compare the relative performance of two fault tolerant mechanisms dealing with repairable and non-repairable components that have failed. The relative improvement in the reliability and safety of a system with repairable components is calculated with respect to the corresponding system where the components are not repairable. The fault tolerant systems under study correspond to...

active queue management (aqm) plays an important role in the internet congestion control. it tries to enhance congestion control, and to achieve tradeoff between bottleneck utilization and delay. random early detection (red) is the most popular active queue management algorithm that has been implemented in the in internet routers and is trying to supply low delay and low packet loss. red algori...

ABSTRACT The present paper, considered the allocation problem of repairable components for a parallel-series system as a multi-objective optimization problem for two different models. In the first model, the reliability of subsystems are considered as different objectives. While in the second model, the cost and time spent on repairing the components are considered as two different objectives. ...

This paper presents a method using stochastic simulation to evaluate the reliability of robot teams consisting of modular robots. For an example planetary exploration mission we use this method to compare the performance of a repairable robot team with spare modules versus nonrepairable robot teams. Our results show that for this mission a repairable robot team can provide a higher probability ...

Bacteria have diverse mechanisms for competition that include biosynthesis of extracellular enzymes and antibiotic metabolites, as well as changes in community physiology, such as biofilm formation or motility. Considered collectively, networks of competitive functions for any organism determine success or failure in competition. How bacteria integrate different mechanisms to optimize competiti...

In this paper, a hybrid meta-heuristic approach is proposed to optimize the mathematical model of a system with mixed repairable and non-repairable components. In this system, repairable and non-repairable components are connected in series. Redundant components and preventive maintenance strategies are applied for non-repairable and repairable components, respectively. The problem is formulate...

Sc doping in Pb(Mg1/3Nb2/3)O3 enhances the B-site 1:1 cation order significantly but promotes the ferroelectric polar order moderately. At low doping levels, the electrical polar domains remain at the nanometer scale and the relaxor ferroelectric behavior is preserved. A normal ferroelectric state can be triggered with electric fields from the relaxor state at lower temperatures. This electric-...