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1.
Anguilla is a UK overseas (non-independent) territory in the Caribbean. It is a small middle-income island with a population of 13 000, and recent statistics indicate that it is more dependent on tourism than any other country or territory in the world. Rapid population growth and development have placed more emphasis on the need for human health and environmental protection. For the first time, a systematic water-quality monitoring programme has been developed, based on the realities of the local situation, e.g. low resource base, limited capabilities, dependence on household rainwater catchment, storage cisterns, and a poor water-supply network. Development of the programme incorporated the key themes of pragmatic, realistic, incremental, responsive, and consultative approaches.  相似文献   
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Sco.  JGP John.  HP 《电网技术》1995,19(8):42-47
本文叙述了由安装在英国国家电网公司新国调中心的新型能量管理系统所提供的实时网络分析的应用,并介绍了第一年的运行经验.对经常出现的某些状态估计问题的解决方法和作者所作的尝试的结论进行了讨论,以对安全估计器的结果与现有的离线研究方法的结果进行比较.文章还对应用实时网络分析时遇到的一些原始缺陷的观察结果和在短时段及较长时段内解决这些问题的方法进行了讨论.  相似文献   
4.
T he A lbert R eservoir of the Yorkshire Water Authority was built in the 1850s as the final raw water storage in the chain of impounding and storage reservoirs which feed Halifax, Brighouse, and Elland in West Yorkshire (Fig. 1).
This paper describes the problems encountered with increasing raw water colour since the mid1970s, the action taken to pretreat the water at the Albert reservoir prior to pressure filtration at the Thrum Hall Water Treatment Works (WTW), and the resulting problems with the deposited alum sludge in Albert reservoir.  相似文献   
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For many decades, anaerobic digestion has been the most important technique of sewage sludge treatment at larger sewage-treatment works. Also, the low running costs of the process make it attractive for the treatment of strong industrial effluents. This paper reviews these advantages and discusses some disadvantages of the anaerobic treatment of industrial effluent. Operating and cost data are presented from Europe and from a detailed UK case study which supports the conclusion that anaerobic treatment will be the most cost-effective method of treatment of strong industrial effluents such as those from food and paper processing.  相似文献   
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J.F. Lyness  BSc  MSc  PhD  CEng  MICE  MIStructE  W. R. C. Myers  BA  BSc  PhD  CEng  MICE  J. B. Wark  BEng  PhD 《Water and Environment Journal》1997,11(5):335-340
Flow measurements have been taken for steady and unsteady flows on a reach of a river having a compact compound channel. The 'single channel', 'divided channel' and 'lateral' distribution methods have been used to calculate conveyances for use in a one-dimensional unsteady flow model of the reach. Comparisons with measured flows show that the divided channel method and the lateral distribution method both underestimate floodplain flow depths. The lateral distribution method gives the closest accuracy in the relative depth range 0.15 ≤ Yr < 0.40. For large flow depths the single channel method becomes more accurate and slightly over-estimates flow depths.
The accuracy of unit width discharge distributions, calculated from the lateral distribution method are assessed by comparison with observed distributions for overbank flows.  相似文献   
7.
Laboratory-Scale Investigations of Algal Toxin Removal by Water Treatment   总被引:1,自引:0,他引:1  
The paper describes some water-treatment processes which have been investigated on a laboratory and pilot-plant scale for their effectiveness in removing toxic algal cells and the dissolved toxins microcystin-LR and anatoxin-a. Oxidation with ozone or potassium permanganate, or treatment by biological activated carbon, were found to be the most effective processes for removal of the dissolved toxins. Chlorination was effective only for the removal of microcystin-LR. Toxins, contained within algal cells, could be removed effectively by coagulation, clarification and filtration under suitable conditions. Consideration of the structure and properties of micro-cystin variants suggests that treatments which are suitable for removal of microcystin-LR and anatoxin-a should be suitable for removal of other microcystins.  相似文献   
8.
ABSTRACT

Human hacking is a nontechnical kind of intrusion that relies heavily on human manipulation. Its impact is continuously giving serious concern in the Information technology arena which has often been undermined due to the ease with which this technique is widely used to infiltrate networks through unsuspecting individuals that are undeniably considered the “weakest link” in the security circle. Security awareness that brings about behavioral change, reduces employees' vulnerability, and protects against threats exploiting employees' vulnerability having a positive impact overall on risks related to information assets. Strategies for developing and implementing a successful information security awareness program are presented in this article, which also provides an introduction to the subject of human hacking while discussing the various counter-measures available to minimize the likelihood of such occurrences and their financial, reputation, psychological, and legal ramifications.  相似文献   
9.
The construction of small sewage-treatment works in Japan is increasing. In most municipalities, economical and effective treatment/maintenance systems, which match the local conditions, are needed. As one of its support strategies, the Japan Sewage Works Agency has initiated and implemented 'co-operation' projects. In one of these projects, a mobile sludge dewatering unit has been shown to be the most economical method of treatment. The first unit, which was commissioned in March 1992, is being used in three municipalities, and this paper appraises its use.  相似文献   
10.
Trials Using a Mobile Ultraviolet Disinfection System in South West Water   总被引:1,自引:0,他引:1  
Ultraviolet radiation has been shown to be effective for disinfecting secondary effluents, and the National Rivers Authority has given conditional approval for its use at sites where disinfection can be justified.
This paper describes the findings of disinfection trials on five different sewage works' effluents using low-pressure ultraviolet systems. The study examines and compares the disinfection performance of clean units and their deterioration in performance due to fouling effects. Conclusions are drawn on the effectiveness of ultraviolet disinfection in the removal of pathogens and pathogen surrogates.  相似文献   
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