Grids reliability remains an order of magnitude below clusters on production infrastructures. This work is aimsed at improving grid application performances by improving the job submission system. A stochastic model, capturing the behavior of a complex grid workload management system is proposed. To instantiate the model, detailed statistics are extracted from dense grid activity traces. The mo...

This study intended to develop a model describing speaking strategies for EFL learners by taking into account the effects of learners’ gender and proficiency on the application of strategies. Accordingly, this study was planned to have two main analyses, namely qualitative and quantitative. In this respect, 30 EFL learners' viewpoints were sought, and then, based on the elicited responses, a 21...

abstract: In the present work, determining the optimal strategy(profit based) of multi virtual power plants (VPPs) as well as the objective of maximizing profit through the multi-level control of VPPs are discussed by the micro-grid utilization center including virtual power plants. VPPs include renewable resources such as wind farms, photovoltaic, and conventional resources such as fuel cell, ...

-In the micro-grid, droop control strategy simulates traditional power system droop characteristics , by changing the output of active and reactive power to control the output voltage frequency and amplitude, thus the micro-grid system can work at the stabilize voltage point in island operation mode . And the voltage is more or less with the grid-connect mode,so that the transition is smooth wh...

Abstract: A Data Grid connects a collection of geographically distributed computational and storage resources that enables users to share data and other resources. Data replication, a technique much discussed by Data Grid researchers in recent years creates multiple copies of file and places them in various locations to shorten file access times. In this paper, a dynamic data replication strate...

although lcl filters are used widely in the grid connected inverters to reduce high-orderharmonics, such a system increases system order and therefore sustainable design of closed-loopcontroller system will be complicated. recently, the single-loop control strategy has beensuggested for l or lc filter based grid-connected inverters. however, the use of single-loopcontrol directly in lcl filter-...

In a world-wide computational Grid, users typically want their jobs to be executed as fast as possible, while the goal of a Grid infrastructure is to assure specific quality of service for all users. In order to reconcile these apparently contrasting goals, the authors proposed an economybased strategy to be used in a Data Grid for efficient access to and distribution of data replicas [20] need...

In this paper we present a decentralized model for scheduling independent tasks in Federated Grids. This model consists in a set of meta-schedulers on each of the grid infrastructures of the Federated Grid. Each meta-scheduler has to implement a mapping strategy in order to improve two of the most common objective functions of tasks scheduling problems: makespan and resource performance. We con...

load management and cost optimization are among the important factors in trigenerationsystems and combined cooling, heating and power (cchp) systems. in this study, an innovative cchpsystem uses a gas turbine as the prime mover and has a heat recovery steam generator (hrsg) in addition toan auxiliary boiler, electric and absorption chillers. the system is tied with the bulk electric grid; to ex...