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1.
In Latin America and the Caribbean, the available information about the causes and consequences of risk is scarce and barely meets the needs of project engineers and decision makers. Although local governments and communities typically who bear the brunt of the losses, they do not participate in the definitions and are not informed about the “acceptable” level of risk or how to reduce it. The formulation and adoption of risk management criteria (supported by engineering geological modelling), throughout the cycle of development/investment projects, should take account of the affected communities and how they can play a part in the decision making. This requires an increased awareness and understanding of both natural hazards and vulnerability. The paper analyses best practices based on experiences from Latin America and the Caribbean, which may be useful for the evaluation of hazards and vulnerability and lead to proactive risk management.  相似文献   

2.
This paper examines the impact of flood risk on the value of English residential properties. We find that a location within a flood zone significantly lowers property values even if we control for the proximity to a watercourse, the history of flooding and neighbourhoods effects. Although the flood risk discount is more compelling for waterfront properties, it is still highly significant for dwellings further from the water. The markdown arises around 2004–2005, which coincides with the publication of detailed flood maps by the UK Environment Agency and with a more risk-based pricing of flood insurance policies. As expected, the effect of flood risk on house prices is stronger in the months following major flood events but, interestingly, it almost disappears in a hot market when buyers have arguably less negotiating power.  相似文献   

3.
Nnane DE  Ebdon JE  Taylor HD 《Water research》2011,45(6):2235-2246
In many parts of the world, microbial contamination of surface waters used for drinking, recreation, and shellfishery remains a pervasive risk to human health, especially in Less Economically Developed Countries (LEDC). However, the capacity to provide effective management strategies to break the waterborne route to human infection is often thwarted by our inability to identify the source of microbial contamination. Microbial Source Tracking (MST) has potential to improve water quality management in complex river catchments that are either routinely, or intermittently contaminated by faecal material from one or more sources, by attributing faecal loads to their human or non-human sources, and thereby supporting more rational approaches to microbial risk assessment. The River Ouse catchment in southeast England (U.K.) was used as a model with which to investigate the integration and application of a novel and simple MST approach to monitor microbial water quality over one calendar year, thereby encompassing a range of meteorological conditions. A key objective of the work was to develop simple low-cost protocols that could be easily replicated. Bacteriophages (viruses) capable of infecting a human specific strain of Bacteroides GB-124, and their correlation with presumptive Escherichia coli, were used to distinguish sources of faecal pollution. The results reported here suggest that in this river catchment the principal source of faecal pollution in most instances was non-human in origin. During storm events, presumptive E. coli and presumptive intestinal enterococci levels were 1.1-1.2 logs higher than during dry weather conditions, and levels of the faecal indicator organisms (FIOs) were closely associated with increased turbidity levels (presumptive E. coli and turbidity, r = 0.43). Spatio-temporal variation in microbial water quality parameters was accounted for by three principal components (67.6%). Cluster Analysis, reduced the fourteen monitoring sites to six representative ‘sentinel’ sites. The correlation coefficient between presumptive E. coli and phages of Bacteroides GB-124 was very small (r = 0.05) whilst that between turbidity and suspended solids was high (r = 0.62). Variations in climate, animal and anthropogenic interferences were all, either directly or indirectly, related to faecal contamination. The findings show the importance of meteorological conditions, such as storm events, on microbial water quality, and suggest that any future increases in the frequency of storm events (associated with climate change) are likely to result in a greater incidence of FIO/pathogen loads. This low-cost approach could help to predict spatio-temporal ‘hotspots’ of elevated waterborne disease risk. The work also represents an important step towards integrating novel MST tools into river catchment modelling.  相似文献   

4.
Requirements of the EU Water Framework Directive for the introduction of ecological quality objectives for surface waters and the stipulation that all surface waters in the EU must be of 'good' ecological status by 2015 necessitate a quantitative understanding of the linkages among catchment attributes, water chemistry and the ecological status of aquatic ecosystems. Analysis of lotic ecological status, as indicated by an established biotic index based primarily on benthic macroinvertebrate community structure, of 797 hydrologically independent river sites located throughout Ireland showed highly significant inverse associations between the ecological status of rivers and measures of catchment urbanisation and agricultural intensity, densities of humans and cattle and chemical indicators of water quality. Stepwise logistic regression suggested that urbanisation, arable farming and extent of pasturelands are the principal factors impacting on the ecological status of streams and rivers in Ireland and that the likelihood of a river site complying with the demands of the EU Water Framework Directive, and be of 'good' ecological status, can be predicted with reasonable accuracy using simple models that utilise either widely available landcover data or chemical monitoring data. Non-linear landcover and chemical 'thresholds' derived from these models provide a useful tool in the management of risk in catchments, and suggest strongly that more careful planning of land use in Ireland is essential in order to restore and maintain water quality as required by the Directive.  相似文献   

5.
In recent years, increased attention has been focused on models for risk assessment of source areas in agricultural landscapes. Among the simplest of such models are index tools, which have been developed particularly for phosphorus (P) and to some extent nitrogen (N). However, only a few studies have considered the development of an integrated management strategy that includes erosion and losses of both P and N. Accordingly, the major objective of this study was to initiate the development of an integrated risk assessment tool, consisting of indices for erosion, P and N. The strategy used to create the integrated tool was based on the assumption that all input data at field scale should be readily available either from ordinary agricultural statistics or from the farmer. The results from using the indices in a pilot case study catchment illustrated that losses of P and N had often different critical source areas. The P index was highest for fields with manure application and/or high soil P status or with autumn ploughing, and the N index was highest for fields with excessive N application. The integrated risk was greatest for areas with manure application and some areas with a high erosion risk in combination with high nutrient application rate. Additionally, four different management options were assessed: (1) reduced fertilisation, (2) catch crops, (3) autumn ploughing, and (4) no autumn ploughing. The results verified that reduced nutrient application and stubble during autumn and winter led to the largest decrease in index values, and it was also apparent that management changes in high-risk areas had the greatest impact on the indices. Overall, our findings indicate that the present integrated risk assessment tool with readily available input data can be used to rank farm fields according to risk of soil erosion and losses of P and N.  相似文献   

6.
The paper presents a novel methodology (RICH, Ranking and Identification of Chemical Hazards) for ranking and identification of xenobiotic organic compounds of environmental concern in stormwater discharged to surface water. The RICH method is illustrated as a funnel fitted with different filters that sort out problematic and hazardous compounds based on inherent physico-chemical and biological properties. The outcomes of the RICH procedure are separate lists for both water phase and solid phase associated compounds. These lists comprise: a justified list of compounds which can be disregarded in hazard/risk assessments, a justified list of stormwater priority pollutants which must be included in hazard/risk assessments, and a list of compounds which may be present in discharged stormwater, but cannot be evaluated due to lack of data. The procedure was applied to 233 xenobiotic organic chemicals (XOCs) of relevance for stormwater. Of these 233 compounds, 121 compounds were found to be priority pollutants with regard to solids phases (i.e. suspended solids, soil, or sediments) when stormwater is discharged to surface water and 56 compounds were found to be priority pollutants with regard to the water phase. For 11% of the potential stormwater priority pollutants the screening procedure could not be carried out due to lack of data on basic physico-chemical properties and/or data on bioaccumulation, resistance to biodegradation, and ecotoxicity. The tiered approach applied in the RICH procedure and the focus on the phases relevant for monitoring or risk assessment in the aquatic environment refines the list of "compounds of concern" when compared to the outcome of existing classification schemes. In this paper the RICH procedure is focused on effects in the aquatic environment exemplified with xenobiotic organic compounds (XOCs) found in urban stormwater, but it may be transferred to other environmental compartments and problems. Thus, the RICH procedure can be used as a stand-alone tool for selection of potential priority pollutants or it can be integrated in larger priority setting frameworks.  相似文献   

7.
项目管理中的风险管理分析   总被引:20,自引:0,他引:20  
从风险和风险管理的定义出发,讨论了风险产生及其风险的分类。重点讨论了风险管理中风险识别、风险分析、制订对策和风险监控等四个步骤。基于风险管理认识,详细研究了风险估计的方法、建立风险清单、风险评估、损失大小估计及损失的概率评估等。给出了风险管理策略和风险的驾驭和监控。  相似文献   

8.
9.
Contract strategy for design management in the design and build system   总被引:2,自引:0,他引:2  
Project team members in design–build system, including owner’s representatives, design–build (D/B) contractors and architects/engineers, have to adopt new roles in managing the design of large-scale projects. The design responsibility is transferred from the owner’s organization to the D/B contractor who is responsible for the design management in the projects to be delivered by the design–build procurement system. However, there remains the concern of design management between the designer and the constructor within the D/B organization, or between the joint venture parties of a D/B project. This paper presents a study, which reviews the issues concerning the design liability and contractual provisions for design management between the designer and D/B contractor in the said contractual arrangements of design–build system. It disseminates the results of a questionnaire survey and structured interviews of three groups of project participants: owners, designers and D/B contractors. The roles and responsibilities of the parties involved in design and design management are less than clear in their respective engagement contracts. In order to improve the design management of design–build projects, this paper recommended some strategic items to be considered in drafting contracts between owners/D/B contractors, D/B contractors/designers and owners/independent checkers to address the issues.  相似文献   

10.
Probabilistic risk assessment for bridges under natural hazards is of great interest to engineers for the development of risk mitigation strategies and implementation plans. The present study evaluates risk of an existing highway bridge in California, USA, under the integrated impact of regional seismic and flood hazards. A sensitivity study combining tornado diagram and first-order second moment reliability analyses is conducted to screen significant uncertain parameters to which bridge response is mostly sensitive. A rigorous uncertainty analysis, employing random sampling and Monte Carlo simulation techniques, is performed to obtain variations in fragility and risk curves of the bridge. Observed variations in risk curves at various risk levels are quantified through 90% confidence intervals and coefficients of variation (COV) of risk. It is observed that uncertainty in the estimated risk increases due to the presence of flood hazard at the bridge site, although mean risk does not vary with flood hazard level. Research outcome signifies that the variation in risk due to parameter uncertainty and varied flood hazard level should not be ignored to ensure bridge safety under the stated multi-hazard condition.  相似文献   

11.
本文在系统地论述航天项目特点和航天项目风险管理内涵的基础上,分析了航天项目风险,阐明了航天项目风险管理的现状和必要性,探讨了航天项目风险管理的发展战略.  相似文献   

12.
We test whether airborne gamma ray spectrometer measurements can be used to estimate levels of radon hazard in the Oslofjord region of Norway. We compile 43,000 line kilometres of gamma ray spectrometer data from 8 airborne surveys covering 10,000 km2 and compare them with 6326 indoor radon measurements. We find a clear spatial correlation between areas with elevated concentrations of uranium daughters in the near surface of the ground and regions with high incidence of elevated radon concentrations in dwellings. This correlation permits cautious use of the airborne data in radon hazard evaluation where direct measurements of indoor radon concentrations are few or absent. In radon hazard evaluation there is a natural synergy between the mapping of radon in indoor air, bedrock and drift geology mapping and airborne gamma ray surveying. We produce radon hazard forecast maps for the Oslofjord region based on a spatial union of hazard indicators from all four of these data sources. Indication of elevated radon hazard in any one of the data sets leads to the classification of a region as having an elevated radon hazard potential. This approach is inclusive in nature and we find that the majority of actual radon hazards lie in the assumed elevated risk regions.  相似文献   

13.
在论述了建筑工程项目质量管理现状及加强建筑工程质量管理的意义基础上,从六个方面探讨了完善建筑工程质量管理的一些对策或建议,以期提高我国建筑企业的水平,促进建筑生产的健康发展.  相似文献   

14.
In the context of climate change and the EU flood directive, this paper analyses and explores sustainable flood retention basins (SFRB) as adaptive structures contributing to water resources management and flood risk control. A dataset of 371 potential SFRB (including many operating reservoirs) characterized by 40 variables have been surveyed across central Scotland. However, the spatial properties of these SFRB, such as water storage (which relates to flooding depth) in different regions, are ambiguous. This paper uses geostatistics on the Scottish dataset. Spatial analysis showed that ordinary kriging, which is a spatial interpolation method, could be successfully applied to estimate numerical values for all key flood control variables everywhere in the study area. Moreover, the probability that certain threshold values relevant to flood control managers were exceeded can also be calculated by using disjunctive kriging. The findings provide an effective screening tool in assessing flood control using SFRB.  相似文献   

15.
16.
The relationship between soluble and particulate phosphorus was examined for 9 major UK rivers including 26 major tributaries and 68 monitoring points, covering wide-ranging rural and agricultural/urban impacted systems with catchment areas varying from 1 to 6000 km2 scales. Phosphorus concentrations in Soluble Reactive (SRP), Total Dissolved (TDP), Total (TP), Dissolved Hydrolysable (DHP) and Particulate (PP) forms correlated with effluent markers (sodium and boron) and SRP was generally dominant signifying the importance of sewage sources. Low flows were particularly enriched in SRP, TDP and TP for average SRP > 100 μg/l indicating low effluent dilution. At particularly low average concentrations, SRP increased with flow but effluent sources were still implicated as the effluent markers (boron in particular) increased likewise. For rural areas, DHP had proportionately high concentrations and SRP + DHP concentrations could exceed environmental thresholds currently set for SRP. Given DHP has a high bioavailability the environmental implications need further consideration. PP concentrations were generally highest at high flows but PP in the suspended solids was generally at its lowest and in general PP correlated with particulate organic carbon and more so than the suspended sediment in total.Separation of pollutant inputs solely between effluent and diffuse (agriculture) components is misleading, as part of the “diffuse” term comprises effluents flushed from the catchments during high flow. Effluent sources of phosphorus supplied directly or indirectly to the river coupled with within-river interactions between water/sediment/biota largely determine pollutant levels.The study flags the fundamental need of placing direct and indirect effluent sources and contaminated storage with interchange to/from the river at the focus for remediation strategies for UK rivers in relation to eutrophication and the WFD.  相似文献   

17.
Legislation for Scotland increasingly requires that environmental enhancement schemes must be integral in property construction. With the introduction of the Water Framework Directive and the Water Environment and Water Services Act, developments on areas surrounding an existing watercourse often include river restoration and sustainable flood alleviation schemes. To support this, a decision-making tool is proposed that considers the hazard, exposure and vulnerability of a residential development to flooding. Rather than assessing flood risk purely in terms of hydraulic performance, it is shown that appropriate channel design selection also requires information on the socio-economic impacts. This paper takes a novel stance in predicting the social impact of flooding by using statistical evaluation of census data. This holistic approach to flood risk investigation is suitable for use by developers, planners and councils at a local (development) scale to strategically aid flood alleviation works, emergency planning and housing development.  相似文献   

18.
Unexpected ground conditions have always been a major problem for the tunnelling industry. As demand for the development of new underground structures, regardless of the ground conditions, has increased, safety and risk considerations have become even more important. The methodology presented in this paper aims at the identification of risk-prone areas, incorporating, at the same time, the uncertainty of ground conditions. It is focused on TBM tunnelling and can be implemented in the early stages of the project. The methodology assesses the hazards by introducing the concept of a vulnerability index, which is based on the principles of rock engineering systems, to identify the weighting of the parameters, and on probabilistic modelling to address the uncertainty in the parameters’ values. The proposed model is illustrated via the Athens Metro case study, used also for validating its performance under actual construction conditions.  相似文献   

19.
苏幸 《山西建筑》2011,37(6):254-255
针对企业网络化办公中普遍存在的信息安全问题从防范的角度阐述了解决策略及技术,同时提出在企业网络办公信息化安全建设中,必须要进一步建立健全相应的管理制度,强化网络信息安全管理。  相似文献   

20.
梁莉 《福建建筑》2010,(12):108-110
内部控制审计是一种行之有效的风险管理方法。工程项目风险管理的内部控制审计是通过风险的识别、预测和衡量、选择有效的手段,尽可能降低工程费用,有计划地处理风险,以获得企业安全生产,缩短工程时间,提高工程质量,以达到预期目标,实现利润最大化。  相似文献   

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