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11.
Objective comparisons of consignment, just-in-time, and stockless 总被引:20,自引:0,他引:20
Gerber N 《Hospital materiel management quarterly》1991,13(1):10-17
12.
引言电磁频率测深法已经使用了十年之久,特别在西欧,主要用于深部的调查。无论如何,可以期望这种方法应用到地下水勘探中也会体现出某些优点。电磁测深法的第一个优点,它能够用变更频率去变更电流的穿透深度,这比电阻率测深法使用的移动供电电极更为方便。电磁测深法的第二个优点,特别适用于干旱地区,在这样地区由于有高阻抗表层,使得用良导体接地也难以将电流输入地下;当用电磁法时,这种困难就完全可以避免。 相似文献
13.
Akin J Guilkey D Popkin B Flieger W Briscoe J Black RE Adair LS 《Journal of development economics》1992,38(2):323-351
Collaborating researchers used a multi equation model to analyze 3080 mother-infant pairs living on the island of Cebu in the central Philippines and to estimate a child health production function. The econometric methods used eliminated obstacles such as heterogeneity and endogeneity of significant explanatory factors. They also maximized the longitudinal quality of the data. The results showed that morbidity in 1 period reduced infant weight in following periods. For example, diarrhea and febrile respiratory infection reduced growth in the time period following the illnesses. Further effects of some contributing factors were great near birth not diminished with age. For example, breast feeding promoted growth and protected against infection, especially diarrhea and febrile respiratory infection, more substantially near birth than it did later. Further, in urban areas, preventive health care positively affected growth independently of its indirect influence on reducing respiratory infection. Yet it had little effect on diarrhea. Diarrhea had a strong adverse effect on growth. Exposure of the infant to enteric pathogens had the greatest influence on production of diarrhea. In urban areas, exposure included water supply contamination, exposure to feces, a more pathogenic diet, and community crowding. In rural areas, however, exposure included community crowding and increased rainfall which presumably washed feces into the water supply. Household crowding in both urban and rural areas and irritation from smoke in urban areas only tended to bring about febrile respiratory infection. 相似文献
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Understanding urban residential end uses of water 总被引:1,自引:0,他引:1
The 'end use' of water is a breakdown of the total household water usage such as water used for toilets, showers, washing machines, taps, lawn watering, etc. Understanding end uses of water will enable water planners, water authorities and household owners determine where water is used/wasted, how much and how often. This paper describes the end uses of water from a number of single-family homes in Greater Melbourne, Australia. The study involves the analysis of water consumption data recorded at 5-s intervals from logged households collected by Yarra Valley Water in Melbourne in 2004. The study determines how much water is used for outdoor and indoor purposes in a single-family home in Melbourne and compares the water usage during winter and summer. Hourly patterns of major end uses of water are also developed. The aim of this study is to improve the understanding of the end uses of water and to assist where to focus water conservation efforts that would be most effective financially and environmentally, and be acceptable to everyone. 相似文献
16.
Pons MN Potier O Pontvianne S Laurent N France X Battaglia P 《Water science and technology》2011,64(3):602-609
In order to characterize the pollution discharged into the Moselle River and some of its tributaries, spectroscopic techniques, namely UV-vis spectroscopy and synchronous fluorescence spectroscopy, have been combined. UV-visible spectra were analysed using the maximum of the second derivative at 225 nm (related to nitrates), the SUVA254 and E2/E3 indices (related to the nature of organic matter). Synchronous fluorescence spectra (delta lambda = 50 nm) presented different shapes depending upon the type of pollution. The pollution results from anthropogenic activities: untreated domestic sewage due to misconnections in a periurban river, effluent from urban WWTPS, agricultural runoff (nitrates) in several streams, discharge from a paper mill (humic-like substances due to wood processing) and from steel mills (PAHs). 相似文献
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杜克(Duke)能源公司卡罗莱纳(Carolinas)州有限责任公司计划为桥水(Bridgewater)工程装机28 MW的新建水电站安装掺气水轮机。期望这些为现场情况专门设计的水轮机可使杜克能源公司提高工程下游水流中的溶解氧含量,同时也使效率损失降到最小。 相似文献
20.
以基斯罗古布斯卡亚(Kislogubskaya)潮汐电站为例,综述了俄罗斯潮汐电站的发展历程。从修建该电站所采用的建筑材料、建筑方法以及发电机组的选型等方面,对过去40多年的运行经验进行了总结。 相似文献