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51.
In a survey of the practical wind energy resource present in the Tayside Region of Scotland it was estimated that over 1500 km2 of land is suitable for wind energy development in the Region after consideration of a range of physical, technical and institutional factors. Wind speed data for this survey was obtained from the Energy Technology Support Unit (ETSU) UK Wind Speed Data Package. To verify the wind speeds obtained from the ETSU package a representative sample of sites in and around the identified areas of potential in Tayside were modelled for mean annual wind speed using the Wind Atlas Analysis and Application Program (WAsP). The wind speeds for the sites obtained from the WAsP analysis were compared with those obtained from the ETSU UK Wind Speed Data Package and conclusions drawn as to the reliability of the Tayside wind energy survey and the general applicability of the ETSU package for broad wind energy resource assessment. 相似文献
52.
53.
吕汀 《常州信息职业技术学院学报》2006,5(2):12-14
静电复印机是常用的办公设备,复印时要将不同规格的复印纸装入纸盒,经常需要操作者对纸盒进行调整。从使用者的角度讲,要用最小的力气、最简便的方法来完成对机器的操纵。这就需要考虑进行人性化设计。纸盒调整主要有自动监测纸盒尺寸的功能和纸盒内侧挡板(导纸板)的调整。对比不同品牌和不同机型复印机的纸盒设计,可看出人性化设计对方便操作者使用的重要性,也为购买机器时提供了借鉴。 相似文献
54.
通过相关分析,筛选出济阳坳陷控制成藏体系资源丰度的主要地质参数,把成藏体系的资源丰度及其主控地质参数作为神经网络的训练样本,建立了具有预测功能的神经网络结构.与多元线性和多元非线性回归模型预测结果的比较表明,神经网络模型在预测精度上要远高于2种回归预测模型. 相似文献
55.
揭示了城市环境的基本性质的基本特征,研究了城市环境对人的心理影响和生理影响。指出城市环境建设不公要满足人的物质需要,还要满足人的精神需要。 相似文献
56.
药物预防HIV传播是人类战胜HIV的重要手段。现将预防HIV感染药的研发现状,抗HIV药在预防母婴传播,暴露前后预防的研发和应用动态作一综述。 相似文献
57.
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
58.
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
59.
Prepulse inhibition (PPI) refers to a reduction in the startle response to a strong sensory stimulus when this stimulus is preceded by a weaker stimulus--the prepulse. PPI reflects a nonlearned sensorimotor gating mechanism and also shows a robust gender difference, with women exhibiting lower PPI than men. The present study examined the eyeblink startle responses to acoustic stimuli of 59 healthy heterosexual and homosexual men and women. Homosexual women showed significantly masculinized PPI compared with heterosexual women, whereas no difference was observed in PPI between homosexual and heterosexual men. These data provide the first evidence for within-gender differences in basic sensorimotor gating mechanisms and implicate the known neural substrates of PPI in human sexual orientation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
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