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31.
The problem of managing water scarcity by resorting to complex interconnected multi-source water systems needs to utilize
management optimization techniques analyzing aspects of water quantity and quality in a common strategy. In the southern regions
of Mediterranean Europe, the greater part of water resources for supply systems are derived from artificial reservoirs and
water systems can become quite complex since they interconnect several sources and demand centers, as indeed occurs in the
Region of Sardinia (Italy). A simplified approach to the requirement to insert water quality aspects in the mathematical optimization
model can be achieved by examining the trophic conditions of reservoirs. Trophic State Indexes (TSI) based on Carlson’s (1977) make it possible to insert quality constraints in the water management optimization model also considering complex multi-reservoir
and multi-user systems. Model formalization and implementation by the optimization toolkit WARGI (Water Resource system optimization
aided by Graphical Interface) (Sechi and Zuddas 2000; Manca et al. 2004; Salis et al. 2005) is illustrated in this paper. The usefulness of a mixed quantity–quality optimization approach has been confirmed by WARGI
application to a real multi-reservoir water resources system in southern Sardinia. The optimization model remains computationally
efficient dealing with this complex multi-reservoir system and the obtained results can be seen as a reference target in a
subsequent simulation phase. 相似文献
32.
本文根据电子期刊的定义、特点及图书馆期刊工作所需要面对的问题,就高校图书馆网络环境下期刊工作的设施规划、资料收集、信息开发及读者培训等多方面内容进行了简单探讨,并就如何应对网络环境下图书馆期刊工作的变化提出建议。 相似文献
33.
Argyris G. Kagiannas Thanassis Didis Dimitris Th. Askounis John Psarras 《国际能源研究杂志》2003,27(2):173-186
The needs that an energy supply system must meet are constantly changing, due to technological, social and political reasons. Effective energy planning is a dynamic process that is repeated periodically and adjusts to changing conditions. Energy decision makers and planners are no longer able to rely on inductive decision making since they have to investigate the effect of various decision parameters and possible future changes. To help in this process, models have been developed where estimates of future load growth, candidate power plants, fuels and other key factors can be introduced, from which the planners can evaluate decision parameters and the available alternatives. The paper presents the different methodologies and practices that are used by 11 energy models for energy demand forecasting, supply side management and generation expansion planning, demand side management and integrated resource planning. The paper concludes to the presentation of a strategic appraisal of the examined energy models appropriate for energy planning in Mozambique. Three models are proposed for conducting demand forecasting, generation expansion planning and demand side management. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
34.
Binoy Ravindran Peng Li Tamir Hegazy 《Journal of Parallel and Distributed Computing》2003,63(12):1219-1242
We present two proactive resource allocation algorithms, RBA*-FT and OBA-FT, for fault-tolerant asynchronous real-time distributed systems. The algorithms consider an application model where task timeliness is specified by Jensen's benefit functions and the anticipated application workload during future time intervals is described by adaptation functions. In addition, we assume that reliability functions of processors are available a priori. Given these models, our objective is to maximize aggregate task benefit and minimize aggregate missed deadline ratio in the presence of processor failures. Since determining the optimal solution is computationally intractable, the algorithms heuristically compute sub-optimal resource allocations, but in polynomial time. Experimental results reveal that RBA*-FT and OBA-FT outperform their non-fault-tolerant counterparts in the presence of processor failures. Furthermore, RBA*-FT performs better than OBA-FT, although OBA-FT incurs better worst-case and amortized computational costs. Finally, we observe that both algorithms robustly withstand errors in the estimation of anticipated failures. 相似文献
35.
在分析铁路通信资源结构的基础上,利用地理信息系统技术、数据库技术和客户/服务器(C/S)模式,为铁通(ChinaTietong)各级分公司和运营部门提供一套较为完善的资源管理信息系统。文中分析了铁通资源的结构与资源之间的关联,介绍了系统功能、物理结构及体系结构,详细分析了数据库设计、地理信息系统和系统安全性所采用的关键技术。这套系统的应用对铁通网络管理的现代化将起到重要的推动作用。 相似文献
36.
Udayan Nandkeolyar David P. Christy 《International Journal of Flexible Manufacturing Systems》1992,4(3-4):267-292
Evaluating the design of flexible manufacturing systems is complex. Developing a measure of performance useful for evaluating alternate designs continues to be interesting. Here, total productivity of the system is proposed as an appropriate measure. Specification of parameters based upon strategic considerations for this measure are discussed. Finally, the usefulness of the measure is demonstrated through an example. 相似文献
37.
关于我国资源保障能力的若干思考 总被引:2,自引:1,他引:1
资源保障能力是一国综合国力判断的重要指标之一。本文首先界定了资源保障能力的涵义,然后分析了五个对资源保障能力比较重要的影响因素,即资源禀赋、经济发展水平、科学技术因素、政治因素和人们的资源观,最后得出几点我国提高资源保障能力的建议以供参考。 相似文献
38.
基于多智能体的数控机床资源共享技术研究 总被引:8,自引:1,他引:7
以数控铣床为对象,应用多智能体技术,以解决传统的资源共享所面lI缶的透明度低和效率低下的问题。首先,在分析功能模型的基础上,提出并实现了资源共享的四层网络拓扑结构;其次,构造了面向设备资源共享功能的智能体信息流模型,以实现四层结构之间的交互;其三,定义了智能体状态函数,并以此为依据,建立了智能体协商机制。所开发的原型系统表明,以上成果有效地提高了数控机床资源共享的透明度和效率。 相似文献
39.
周龙标 《上海电机学院学报》2003,6(2):58-62
改革开放使中国经济实现了持续高速的发展。然而,随着改革的不断深入,国有资产面临着在新经济环境下的角色转换,在此过程中由于各种原因每年有数百亿元的国有资产流失,所以,国有资产的保值增值成为现阶段乃至将来一段时间我国政府的重大经济课题。本文对国有资产的历史和现状进行了分析并从多角度提出了一些管理方面的看法。 相似文献