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61.
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
62.
Sergei Nirenburg 《Machine Translation》1992,7(1-2):99-124
This report describes the current state of our central research thrust in the area of natural language generation. We have already reported on our text-level theory of lexical selection in natural language generation ([59, 60]), on a unification-based syntactic processor for syntactic generation ([73]) and designed a relatively flexible blackboard-oriented architecture for integrating these and other types of processing activities in generation ([60]). We have implemented these ideas in our prototype generator, Diogenes — a DIstributed, Opportunistic GENEration System — and tested our lexical selection and syntactic generation modules in a comprehensive natural language processing project — the KBMT-89 machine translation system ([15]). At this stage we are developing a more comprehensive Diogenes system, concentrating on both the theoretical and the system-building aspects of a) formulating a more comprehensive theory of distributed natural language generation; b) extending current theories of text organization as they pertain to the task of planning natural language texts; c) improving and extending the knowledge representation and the actual body of background knowledge (both domain and discourse/pragmatic) required for comprehensive text planning; d) designing and implementing algorithms for dynamic realization of text structure and integrating them into the blackboard style of communication and control; e) designing and implementing control algorithms for distributed text planning and realization. In this document we describe our ideas concerning opportunistic control for a natural language generation planner and present a research and development plan for the Diogenes project.Many people have contributed to the design and development of the Diogenes generation system over the last four years, especially Eric Nyberg, Rita McCardell, Donna Gates, Christine Defrise, John Leavitt, Scott Huffman, Ed Kenschaft and Philip Werner. Eric Nyberg and Masaru Tomita have created genkit, which is used as the syntactic component of Diogenes. A short version of this article appeared in Proceedings of IJCAI-89, co-authored with Victor Lesser and Eric Nyberg. To all the above many thanks. The remaining errors are the responsibility of this author. 相似文献
63.
上海市电话局用户接入网建设经历了调研、网络规划、启动实施和进一步完善、规范四个怅阶段、现已基本形成了覆盖政府机关、大专院校、医院、商务大楼及高层建筑、新建住宅小区、区级以上图书馆等范围的用户光纤网络,为加快经济建设步伐、满足多层次用户需求、拓展电信新业务打下了坚实基础。 相似文献
64.
在CIMS环境下,针对箱体零件CAD、CAPP、CAM信息集成的功能需求,在基于特征的箱体零件信息模型、工艺计划模型与服务于工艺设计的制造环境模型的支持下,开发出了特征造型,工艺设计及加工过程仿真与NC编程等子系统,从而完成了一个集成化的箱体零件CAD/CAPP/CAM系统。 相似文献
65.
通过对西安绿色康居小区规划设计的实例分析,阐明了小康型住宅区的标准和要求,在旧城住宅区改造中的落实和运用,试图探索下一世纪旧城住宅区的改造之路. 相似文献
66.
本文结合为某机械厂开发的实用计算机辅助工艺设计系统(JJCAPP),论述了一种兼有派生式和创成式特点的综合式工艺自动设计方法. 相似文献
67.
68.
在水电的前期设计阶段,规划专业的重要性显而易见。由于水电规划工作涉及专业很多,如果仅停留于规划专业本身,未必能解决问题。在规划工作中,既有定量的计算,也有定性的分析;既要站在国家的角度进行评价,也要进行企业的财务效益分析;既要考虑目前的现实情况,也要对未来的发展做出预测;既有企业的主观意志,也有自然、社会历史的限制。总之,规划专业是涉及多目标、多量纲的综合判断,若以局部来通观全体,则一定要流于片面的谬误。因此,水电规划工作须进行辩证的综合研究。 相似文献
69.
70.
Traditionally, companies used to view themselves as separate entities and did not devote efforts to collaborate with other echelons of the extended enterprise. This even happened at multi-site companies owning different plants that belonged to the same supply chain. However, manufacturing facilities of the same supply chain should intensively share information and coordinate planning and scheduling tasks in order to get a globally optimized solution. This paper discusses some specific characteristics of the planning and scheduling problem in the extended enterprise including an analysis of a case study, and reviews the available state-of-the-art research studies in this field. Most studies suggest that integrated approaches can have a significant impact on the system performance, in terms of lower production costs, and less inventory levels. The paper provides some conclusions and suggestions of future works. 相似文献