The issue of unit commitment is one of the most important economic plans in power system. In modern and traditional power systems, in addition to being economical of the planning, the issue of security in unit operation is also of great importance. Hence power system operation confronts units’ participation and input considering network security constrains. The issue of units’ participation is ...

In this investigation, the explicit expressions for reliability function and mean time to failure (MTTF) of a repairable system with provision of spares and removable multi-repair facility have been established. In removable repairmen strategy, the repairmen turn on when there are N or more than N failed units and turn-off when system is empty. The failure times of operating/spare units and rep...

Mixed ferroelectrics exhibit unusual precursor effects. In KTa12xNbxO3, polar nanoregions have been shown to condense approximately 20 K above the transition for all Nb concentrations, 1.2%,x,50%, as a result of medium-range collective interactions between Nb off-center ions. These interactions are also responsible for the observation of hysteresis loops in the polarization and dielectric nonli...

We solve the problem of cargo transfer in high sea states over a ramp from a large, medium-speed, rollon/roll-off (LMSR) vessel to a smaller connector vessel of a surface effect ship (SES) type. Our aim is to reduce rampmotion between the LMSR and SES in order to provide a safer environment for cargo transfer. We design an air cushion actuated controller to estimate and cancel the wave disturba...

conclusions thus, we can conclude that a simulator system using an extracorporeal circulation system can be set to different models of dialyzers, and that the reproduced treatment scenarios can be used for simulation training. results the results of the tests demonstrated successful activation of the alarms by the dialysis apparatus, which were appropriate for each of the five types of accident...

Abstract:   A two-dimensional fully implicit finite difference model, which can be easily extended to three dimensions, is developed to study the effect of cut-off walls on saltwater intrusion into the aquifers. This model consists of a coupled system of two nonlinear partial differential equations which describe unsteady density-driven groundwater flow and solute transport. The numerica...

daily sunshine duration is one of the factors influencing the size of solar panels in a photovoltaic system. when the system is designed and the number of system components is calculated, the average of sunshine hours is usually used. however, sunshine hours are less than average and we are faced to shortage and surplus of electricity in the winter and summer, respectively. in this paper due to...