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Risk management entails knowledge of the risk and how best to reduce it; its objective is to minimize losses arising from existing or potential risk. With effective contingency planning, risk analysis and its corollary, consequence analysis, can contribute synergistically to improved risk management. Until recently, risk analysis and contingency or emergency response planning were considered distinct disciplines with little interactive potential. Fortunately, industry now recognizes that linking the two can help ensure public safety as well as preserve the financial integrity of plant owners. Both areas are receiving increased and well-deserved attention; several incidents in recent years have demonstrated that losses could have been greatly reduced if better precautions and procedures had been in place as a result of risk analysis and contingency planning.  相似文献   
63.
城市生态系统能值分析(EMA)的原理与步骤   总被引:7,自引:0,他引:7  
将城市自然-经济-社会复合生态系统作为研究对象,介绍能值分析方法在城市生态学动态研究和定量研究中的应用原理与步骤,为人们客观评价自然环境对城市发展的贡献提供科学依据。  相似文献   
64.
Knowledge of customer requirements (CRs) allows manufacturers to effectively reduce the time-to-market for products and maintain a high-level of quality through customer satisfaction. Acquisition, definition, and decomposition of such requirements is therefore a first step in the product design process and key for successful product development. Of building importance in these requirements is for sustainable or green products. Thus has developed the method of Design for Environment (DFE) in product design process, which calls designers to not only understand CRs for product function, structure and economic attributes, but in social and environmental impacts. Thus, the need for elicit environmental customer requirements (ECRs) from various traditional CRs becomes apparent along with the need to meet those requirements in the design process.In the present paper, initial CRs are decomposed and categorized into functional customer requirements (FCRs), performance customer requirements (PCRs) and ECRs. Such an analysis is made based on the analysis of environmentally friendly products (EFPs), environmentally conscious customers, and the characteristics of their CRs, Furthermore, the decomposing method based on semantic analysis is given along with a developed quality function deployment for environment (QFDE) method. These methods create a shift from initial CRs to DFE oriented technical parameters (TPs). Finally, the acquisition and conversion of CRs of the automatic soybean milk maker in the DFE process is taken as an example to validate and analyze the above-mentioned method.  相似文献   
65.
Abstract: The U.S. Environmental Protection Agency (USEPA) Office of Pesticide Programs (OPP) has completed an evaluation of three watershed‐scale simulation models for potential use in Food Quality Protection Act pesticide drinking water exposure assessments. The evaluation may also guide OPP in identifying computer simulation tools that can be used in performing aquatic ecological exposure assessments. Models selected for evaluation were the Soil Water Assessment Tool (SWAT), the Nonpoint Source Model (NPSM), a modified version of the Hydrologic Simulation Program‐Fortran (HSPF), and the Pesticide Root Zone Model‐Riverine Water Quality (PRZM‐RIVWQ) model. Simulated concentrations of the pesticides atrazine, metolachlor, and trifluralin in surface water were compared with field data monitored in the Sugar Creek watershed of Indiana’s White River basin by the National Water Quality Assessment (NAWQA) program. The evaluation not only provided USEPA with experience in using watershed models for estimating pesticide concentration in flowing water but also led to the development of improved statistical techniques for assessing model accuracy. Further, it demonstrated the difficulty of representing spatially and temporally variable soil, weather, and pesticide applications with relatively infrequent, spatially fixed, point estimates. It also demonstrated the value of using monitoring and modeling as mutually supporting tools and pointed to the need to design monitoring programs that support modeling.  相似文献   
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正Dr.Samuel M.Cohen of the University of Nebraska Medical Center,who has recently published in the Journal of Environmental Sciences(Cohen et al.,2016),is the recipient of the Merit Award from the Society of Toxicology(USA)."The Merit Award is presented to a member of the Society of Toxicology in recognition of distinguished contributions to toxicology throughout an  相似文献   
68.
From 1999 through 2010, a team of scientists and engineers systematically reviewed approximately eight million classified and unclassified documents at Los Alamos National Laboratory (LANL) that describe historical off-site releases of radionuclides and chemicals in order to determine the extent to which a full-scale dose reconstruction for releases is warranted and/or feasible. As a part of this effort, a relative ranking of historical airborne and waterborne radionuclide releases from LANL was established using priority index (PI) values that were calculated from estimated annual quantities released and the maximum allowable effluent concentrations according to The U.S. Nuclear Regulatory Commission (USNRC). Chemical releases were ranked based on annual usage estimates and U.S. Environmental Protection Agency (USEPA) toxicity values. PI results for airborne radionuclides indicate that early plutonium operations were of most concern between 1948 and 1961, in 1967, and again from 1970 through 1973. Airborne releases of uranium were found to be of most interest for 1968, from 1974 through 1978, and again in 1996. Mixed fission products yielded the highest PI value for 1969. Mixed activation product releases yielded the highest PI values from 1979 to 1995. For waterborne releases, results indicate that plutonium is of most concern for all years evaluated with the exception of 1956 when (90)Sr yielded the highest PI value. The prioritization of chemical releases indicate that four of the top five ranked chemicals were organic solvents that were commonly used in chemical processing and for cleaning. Trichloroethylene ranked highest, indicating highest relative potential for health effects, for both cancer and non-cancer effects. Documents also indicate that beryllium was used in significant quantities, which could have lead to residential exposures exceeding established environmental and occupational exposure limits, and warrants further consideration. In part because of the close proximity of residents to LANL, further study of historical LANL releases and the potential impact to public health is recommended for those materials with the largest priority index values; namely, plutonium, uranium, and selected chemicals.  相似文献   
69.
Dispersal kernels in grid-based population models specify the proportion, distance and direction of movements within the model landscape. Spatial errors in dispersal kernels can have large compounding effects on model accuracy. Circular Gaussian and Laplacian dispersal kernels at a range of spatial resolutions were investigated, and methods for minimizing errors caused by the discretizing process were explored. Kernels of progressively smaller sizes relative to the landscape grid size were calculated using cell-integration and cell-center methods. These kernels were convolved repeatedly, and the final distribution was compared with a reference analytical solution. For large Gaussian kernels (σ > 10 cells), the total kernel error was <10−11 compared to analytical results. Using an invasion model that tracked the time a population took to reach a defined goal, the discrete model results were comparable to the analytical reference. With Gaussian kernels that had σ ≤ 0.12 using the cell integration method, or σ ≤ 0.22 using the cell center method, the kernel error was greater than 10%, which resulted in invasion times that were orders of magnitude different than theoretical results. A goal-seeking routine was developed to adjust the kernels to minimize overall error. With this, corrections for small kernels were found that decreased overall kernel error to <10−11 and invasion time error to <5%.  相似文献   
70.
Sustainable development or sustainability has been highlighted as an essential principle in urban master planning, with increasing recognition that uncontrollable urbanization may well give rise to various issues such as overexploitation of natural resources, ecosystem destruction, environmental pollution and large-scale climate change. Thus, it is deemed necessary to modify the existing urban and regional administrative system so as to cope with the challenges urban planning is being confronted with and realize the purpose of urban sustainability. This paper contributed to proposing a mechanism which helps to make urban planning with full consideration of issues with respect to sustainable development. We suggested that the integration of urban planning, SEA and ecological planning be a multi-win strategy to offset deficiency of each mentioned political tool being individually applied. We also proposed a framework where SEA and ecological planning are fully incorporated into urban planning, which forms a two-way constraint mechanism to ascertain environmental quality of urban planning, although in practice, planning and SEA processes may conditionally be unified. Moreover, as shown in the case study, the integration of the three political tools may be constrained due to slow changes in the contextual factors, in particular the political and cultural dimensions. Currently within the context of China, there may be three major elements which facilitate integration of the three political tools, which are (1) regulatory requirement of PEIA on urban planning, (2) the promotion or strong administrative support from government on eco-district building, and (3) the willingness of urban planners to collaborate with SEA experts or ecologists.  相似文献   
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