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11.
Risk-based decision-making for drilling waste discharges using a fuzzy synthetic evaluation technique 总被引:5,自引:0,他引:5
Offshore petroleum drilling wastes contain toxic substances that are potentially harmful to the marine ecosystem. Despite environmentally benign characteristics, wastes associated with synthetic-based fluids still contain a certain amount of pollutants due to contamination with formation oil and the presence of trace heavy metals in barite, which may pose risk when discharged into the marine environment. A framework is presented here for a decision support system for the selection of the best drilling waste discharge option. Uncertainties in the quantification of risk, cost and technical feasibility are expressed by fuzzy numbers. An analytical hierarchy process with a technique called fuzzy synthetic evaluation is employed to determine the best management alternative (discharge scenario). 相似文献
12.
In recent years, bulk carriers have been identified with high risks of catastrophic structural failure and foundering, and with heavy loss of human life. This study, based upon Lloyd's of London casualty records, identified four risk factors that had significant, independent effect upon the likelihood of a bulk carrier foundering. The risk of foundering increased with the age of the ship, and was related to the ship's flag of registration. Most importantly, however, increased risks were found for heavy cargoes of iron ore and scrap steel or iron, and for trading routes to the Far East and from Europe to North America. Additional safety measures, in particular regarding ship design and high-risk trades, may well be necessary to reduce the high casualty rates. 相似文献
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本文介绍了项目质量管理的特点及构成要素,重点阐述了项目质量管理在施工企业应用的措施,以保证产品质量,为企业创出更高的效益。 相似文献
15.
区域地下水信息管理系统研究 总被引:2,自引:0,他引:2
本文通过《河南省地下水动态信息管理系统》的建立,讨论了区域地下水信息管理系统的设计目标,数据结构和软件实现,着重介绍了系统的软件设计特点,最后指出了这种管理系统在水文地质部门中具有广泛的应用前景。 相似文献
16.
Turkey was struck by two major events on 17 August and 12 November 1999, named Izmit (M w = 7.4) and Düzce (M w = 7.2) earthquakes, respectively. Rubble mound breakwaters in Izmit Bay experienced little damage, as forecasted by the new risk assessment model in which tsunami occurrence risk was included in the damage estimations. In order to determine the occurrence probability of structural damage under design conditions, including the environmental loading parameters of tsunami and storm waves, tidal range and storm surge, the Conditional Expections Monte Carlo simulation was applied in the risk assessment model developed in this study for the Esenköy Fishery Harbour, Turkey. A tsunami was not the key design parameter when compared to storm waves for the main breakwater of the harbour, however, in places with great seismic activity, the tsunami risk should be important depending on the occurrence probability and magnitude of the tsunami. 相似文献
17.
本文通过对国土资源部科技成果管理现状和国内外科技成果管理水平的分析,构建了国土资源科技成果管理主流程信息化发展的基本思路和框架,并对实施国土资源科技成果管理信息化提出了建设性意见。 相似文献
18.
Landslide risk assessment and management: an overview 总被引:29,自引:0,他引:29
Landslides can result in enormous casualties and huge economic losses in mountainous regions. In order to mitigate landslide hazard effectively, new methodologies are required to develop a better understanding of landslide hazard and to make rational decisions on the allocation of funds for management of landslide risk. Recent advances in risk analysis and risk assessment are beginning to provide systematic and rigorous processes to enhance slope management. In recent years, risk analysis and assessment has become an important tool in addressing uncertainty inherent in landslide hazards.This article reviews recent advances in landslide risk assessment and management, and discusses the applicability of a variety of approaches to assessing landslide risk. Firstly, a framework for landslide risk assessment and management by which landslide risk can be reduced is proposed. This is followed by a critical review of the current state of research on assessing the probability of landsliding, runout behavior, and vulnerability. Effective management strategies for reducing economic and social losses due to landslides are described. Problems in landslide risk assessment and management are also examined. 相似文献
19.
河流水质风险评价的灰色-随机风险率方法 总被引:3,自引:2,他引:3
提出了量化影响河流水质的随机不确定性与灰色不确定性的水质超标灰色-随机风险率概念,建立了水质超标灰色-随机风险率评价模型。在水质单项参数评价模型中,将河流污染物浓度变量的分布处理成灰色概率分布,将污染物浓度超过水质类别标准值的风险率处理成灰色概率,即水质超标灰色-随机风险率。在水质综合评价模型中,河流水环境系统被考虑为担任某一使用可能的可靠性系统,而任意一种水质参数超标意味着河流水体使用功能不能得到应有的保证,也即表明水体综合评价超标,最后借鉴系统可靠性分析的理论和方法计算水质综合超标率。该方法应用于黄河花园口断面重金属污染风险评价。 相似文献
20.
分析南宁市旅游商品资源优势及旅游商品开发中存在的问题。根据旅游商品资源优势及旅游商品开发设计的原则 ,设计旅游商品系列和旅游商品销售网点空间布局。提出旅游商品开发生产实施措施 相似文献