At present, a large number of surveillance, scientific, and commercial communications constellations are being actively pmsued by DoD, NASA, and the commercial space community. In many cases, these constellations will be made up of "LightSats" or small, low cost spacecraft. F or such systems, operations costs, which are large in traditional systems, can become a dominant element of total system...

background: health is a national priority and it is always a duty of the government to establish a good and fair health system. the national heath care system reform program and evaluation of health system reform plan funding these programs were enforced by the honorable minister of health and medical education on may 5th, 2014. given the importance of this issue, the present study was conducte...

Knowledge maintenance (KM) is the process of reflecting over some current knowledge based system in order to handle a new situation. Changes that fix new problems must not introduce bugs into old fixes. A common technique for KM is to reflect over dependencies between concepts. In this review, we sample the KM work on modeling dependencies using either a logic-based, a network-based, or a proce...

Abstract Maintenance policy selection for vessel equipment is a multiple criteria decision making. To ensure security, reliability and efficiency of vessel equipment, a maintenance decision model based on risk, availability and cost was proposed according to the characteristics of vessel equipment maintenance. For modeling, analytic network process (ANP) has been employed. And the maintenance p...

Abstract In this work, a stress is given on the evaluation of performance measures of a parallel system under priority with necessary conditions on operation and repair times. The units are identical in nature subject to constant failure. There is a single server who visits the system immediately to rectify the faults whenever occurred in the system. The system undergoes for preventive maintena...

The main coolant system (MCS) plays a vital role in the stability and reliability of nuclear power plant. However, human errors natural disasters may cause some reactor components to fail, resulting severe consequences such as leakage. Therefore, it is crucial perform resilience analysis MCS, effectively reduce prevent losses. In this paper, importance measure (RIM) for performance loss propose...

A condition based preventive and corrective maintenance policy is proposed for a continuously operating system. The condition of the system is assumed to deteriorate with time. The model incorporates both deterioration as well as random common cause failures. The deterioration stages are modeled as discrete state processes. The system is put to random inspection to know the condition. The mean ...