This paper focuses on the problem of scheduling outages to computer systems in complex distributed environments. The interconnected nature of these systems makes scheduling global change very difficult and time consuming, with a high degree of error. In addressing this problem, we describe the constraints on successful outage scheduling. Using these constraints, it describes a solution using Co...

This paper presents a dynamic programming (DP) model of an electric utility’s optimal policy for operating a nuclear power plant (NPP). The utility chooses the level of capacity utilization of the NPP as a function of signals about the NPP’s current operating state. In each period the utility must determine whether or not to operate the reactor, or shut it down for preventive maintenance or ref...

The purpose of this paper is unavailability of the two main types of conve Swedish traction power supply (TPS) system, i.e. static converter. The number of outages and the ou used to analyze and compare the unavailability o converters. The mean cumulative function (MCF) analyze the number of outages and the unavailab the forced outage rate (FOR) concept has been u outage rates. The study shows ...

Society is increasingly dependent on the proper functioning of the electric power system, which in turn supports most other critical infrastructures: water and sewage systems; telecommunications, internet and computing services; air traffic, railroads and other transportation. Many of these other infrastructures are able to operate without power for shorter periods of time, but larger power out...

Effect of birefringent disorder on the Bit Error Rate (BER) in an optical fiber telecommunication system subject to amplifier noise may lead to extreme outages, related to anomalously large values of BER. We analyze the Probability Distribution Function (PDF) of BER for various strategies of Polarization Mode Dispersion (PMD) compensation. A compensation method is proposed that is capable of mo...

Lightning location systems (LLS) provide data on lightning activity such as type, GPS location, exact time of the stroke, current amplitude, measurement error, etc. The proper application LLS using customized software support can be a powerful decision-making tool in control, maintenance and development power systems. utilization requires with specific functionalities. Software functionalities ...

The performance of healthcare systems in terms of patient flow times and utilization of critical resources can be assessed through queueing and simulation models. We model the orthopaedic department of the Middelheim hospital (Antwerpen, Belgium) focusing on the impact of outages (preemptive and nonpreemptive outages) on the effective utilization of resources and on the flow time of patients. S...

Crisis communication during power outages poses several challenges. Frist, the causes of power outages are often events such as severe weather, which also lead to complications. Second, power outages themselves lead to limitations in everyday life. Third, communication infrastructures, that are necessary for crisis communication, are often affected. This work focuses on the communication of the...

Traditional cloud systems are designed to tolerate server or rack-level failures that are uncorrelated and unpredictable. Such systems successfully deliver highly-available cloud services at global scale. However, the increasing criticality of cloud services to the overall world economy is causing concerns about the impact of power/network outages, cyber-attacks, administration errors, or other...