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101.
The Environmental Effects Committee of the ASCE Energy Engineering Division has been developing a report on “Energy Production and Reservoir Water Quality” for publication. The report covers the regulatory framework that dictates much of the procedures for studies related to this topic, the fundamental reservoir hydrodynamics and water quality modeling used in preparing studies, the kinds of studies that can be prepared at different levels of analysis, and a series of applications that illustrate the problems encountered and applications of the various techniques. This study of hydrothermal modeling as applied to examining cooling tower alternatives for an existing steam electric station on a moderately large reservoir is included in this report and is presented here as an illustration of the types of studies included. This particular study subtended the usual steam electric plant cooling water discharge studies that relate to specific regulatory thermal plume size standards, and had to be designed around developing plant and cooling tower operations that would meet specific fisheries requirements for a zone of passage and refuge for fishes throughout the receiving embayment. After being used in developing cooling tower and plant operating details for the designers to work with, it was required that the hydrothermal modeling results be verified under actual tower operating conditions. In addition, it was required that the impact of the combined operations on dissolved oxygen be examined in detail. This paper covers the background to setting up the study, the kinds of statistical comparisons used to verify the hydrothermal studies, and similar studies for the analysis of dissolved oxygen distributions. 相似文献
102.
针对竣工资料核查工作中遇到的一些常见和普遍存在的问题进行了分析、探讨,指出单位工程竣工资料的核查应以核查基建程序资料、综合管理资料及质量保证资料为重点。 相似文献
103.
104.
本文介绍了我国制冷空调用铜管的质量标准:GB/T17791-1999《空调与制冷用无缝铜管》、YS/T440-2001《内螺纹铜管》、GB/T1531-1994《铜及铜合金毛细管》以及《冰箱用高清洁度铜管》和《铜及铜合金无缝翅片管》的制订背景,分析了标准水平,提出了制冷空调用铜管在满足标准的同时,还要加强实物质量的提升。 相似文献
105.
分析了当前家装存在的破坏结构,一味追求奢华,施工质量差等种种误区,提出了搞好家庭装修的关键环节,对促进家装行业健康发展有积极的意义。 相似文献
106.
Using meta-analysis, randomized experiments in education that either clearly did or clearly did not experience student attrition were examined for the baseline comparability of groups. Results from 35 studies suggested that after attrition, the observed measures of baseline comparability of groups did not differ more than would be expected given sampling error. The degree of either overall or differential attrition did not relate to baseline comparability, a finding that held under sensitivity analyses. Also, both overall and differential attrition rates were unrelated to posttest effect sizes. All of these analyses, however, lacked sufficient statistical power to detect small but potentially meaningful effects. Results suggest caution is warranted when applying quality scales and other blanket rules pertaining to attrition that are meant to either serve as inclusion-exclusion criteria or in scoring study quality. Much greater attention is needed to both the reporting of attrition in primary studies and to the development of conceptual and empirical models of the attrition process. These developments would aid further investigation of the relation between attrition and study outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
Kevin Yale Teichman 《Indoor air》1994,4(3):202-211
Deciding between the different policy approaches available for reducing human exposures to indoor pollutants is an exceptionally complex task. These options can range from waiting until more definitive information is available to enacting regulatory standards, with many variations in between. This paper presents some of the factors policy-makers must consider in establishing indoor air quality policies, and the role researchers should play in ensuring that indoor air policies are based on the best available scientific information. 相似文献
108.
从油田现场反应的情况出发,对调整井固井,尾管固井,大位移井套管固井和其他固井的质量问题进行了分析,针对各种问题产生的原因,提出了相应换解决办法。 相似文献
109.
本文介绍了光束的模式、评价光束质量的几种方法,着重介绍了国际标准化组织(ISO)提出的光束传输系数M作为评价光束质量的方法。文中还讨论了光束质量对焊接、切割加工的影响;热透镜效应对加工的影响等。 相似文献
110.
介绍了我国车用汽油的发展轨迹 ,通过与国外先进标准的对比分析了我国车用汽油存在的不足 .指出我国在加入WTO后 ,更应不断升级车用汽油质量标准 ,需要从标准制定、炼油技术等多方面追赶世界先进水平 ,积极研制生产清洁型无污染汽油 ,从根本上消除汽车尾气对环境的污染 . 相似文献