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451.
I. D. Benekos C. A. Shoemaker J. R. Stedinger 《Stochastic Environmental Research and Risk Assessment (SERRA)》2007,21(4):375-390
Groundwater contamination risk assessment for health-threatening compounds should benefit from a stochastic environmental
risk assessment which considers the effects of biological, chemical, human behavioral, and physiological processes that involve
elements of biotic and abiotic aquifer uncertainty, and human population variability. This paper couples a complex model of
chemical degradation and transformation with movement in an aquifer undergoing bioremediation to generate a health risk analysis
for different population cohorts in the community. A two-stage Monte Carlo simulation has separate stages for population variability
and aquifer uncertainty yielding a computationally efficient and conceptually attractive algorithm. A hypothetical example
illustrates how risk variance analysis can be conducted to determine the distribution of risk, and the relative impact of
uncertainty and variability in different sets of parameters upon the variation of risk values for adults, adolescents, and
children. The groundwater example considers a community water supply contaminated with chlorinated ethenes. Biodegradation
pathways are enhanced by addition of butyrate. The results showed that the contribution of uncertainty to the risk variance
is comparable to that of variability. Among the uncertain parameters considered, transmissivity accounted for the major part
of the output variance. Children were the most susceptible and vulnerable population cohort. 相似文献
452.
M. Jerrett K. B. Newbold R. T. Burnett G. Thurston R. Lall C. A. Pope III R. Ma P. De Luca M. Thun J. Calle D. Krewski 《Stochastic Environmental Research and Risk Assessment (SERRA)》2007,21(5):511-522
Assessing the long-term benefits of marginal improvements in air quality from regulatory intervention is methodologically
challenging. In this study, we explore how the relative risks (RRs) of mortality from air pollution exposure change over time
and whether patterns in the RRs can be attributed to air quality improvements. We employed two-stage multilevel Cox models
to describe the association between air pollution and mortality for 51 cities with data from the American Cancer Society (ACS)
cohort (N = 264,299, deaths = 69,819). New pollution data were computed through models that predict yearly average fine particle (PM2.5) concentrations throughout the follow-up (1982–2000). Average PM2.5 concentrations from 1999 to 2000 and sulfate concentrations from 1980 were also examined. We estimated the RRs of mortality
associated with air pollution separately for five time periods (1982–1986, 1987–1990, 1991–1994, 1995–1998, and 1999–2000).
Mobility models were implemented with a sub-sample of 100,557 subjects to assist with interpreting the RR estimates. Sulfate
RRs exhibit a large decline from the 1980s to the 1990s. In contrast, PM2.5 RRs follow the opposite pattern, with larger RRs later in the 1990s. The reduction in sulfate RR may have resulted from air
quality improvements that occurred through the 1980s and 1990s in response to the acid rain control program. PM2.5 concentrations also declined in many places, but toxic mobile sources are now the largest contributors to PM in urban areas.
This may account for the heightened RR of mortality associated with PM2.5 in the 1990s. The paper concludes with a three alternative explanations for the temporal pattern of RRs, each emphasizing
the uncertainty in ascribing health benefits to air quality improvements. 相似文献
453.
Gheorghe Duca 《洁净——土壤、空气、水》2007,35(1):17-25
An overview is presented on the research in Ecological Chemistry performed recently in the NIS countries in various research areas, including: ecological chemistry of water, air, soil, waste management and cleaner production, and chemical risk management. General links of Ecological Chemistry to other scientific areas are shown. The main environmental problems and anthropogenic impacts are mentioned, among them those which are specific for the NIS countries, and recent results, both of theoretical and practical significance, which were obtained by various research teams of the NIS countries are presented. 相似文献
454.
A disaster risk management performance index 总被引:2,自引:4,他引:2
The Risk Management Index, RMI, proposed in this paper, brings together a group of indicators that measure risk management
performance and effectiveness. These indicators reflect the organizational, development, capacity and institutional actions
taken to reduce vulnerability and losses in a given area, to prepare for crisis and to recover efficiently from disasters.
This index is designed to assess risk management performance. It provides a quantitative measure of management based on predefined
qualitative targets or benchmarks that risk management efforts should aim to achieve. The design of the RMI involved establishing a scale of achievement levels
or determining the distance between current conditions and an objective threshold or conditions in a reference country, sub-national region, or city.
The proposed RMI is constructed by quantifying four public policies, each of which is described by six indicators. The mentioned
policies include the identification of risk, risk reduction, disaster management, and governance and financial protection.
Risk identification comprises the individual perception, social representation and objective assessment; risk reduction involves
the prevention and mitigation; disaster management comprises response and recovery; and, governance and financial protection
policy is related to institutionalization and risk transfer. Results at the urban, national and sub-national levels, which
illustrate the application of the RMI in those scales, are finally given. 相似文献
455.
María Celia García 《GeoJournal》2007,70(4):289-296
The paper focuses on the concentration of nitrates detected in superficial waters (lake and streams) and groundwater (wells)
used as sources of water supply. It attempts to determine the level of risk due to the presence of urban industrial uses and
correlate it with the quality of urban life, in order to determine social vulnerability to the risk of industrial contamination.
A geographic information system (GIS) was constructed with layers for various census data, topographic and landuse features
and the location of water samples. An index of quality of life was developed using selected variables. This was then compared
to the essential services provision data and the results of the water sample analyses. The concentration of nitrates (mg/l
or ppm) in the water samples was determined. These values were translated into maps of contaminants, which were then correlated
with their possible sources and with the quality of life of the population affected. The concentration of nitrates in wells
has been considered alarming, but more concern has been expressed about concentrations in the public water supply network.
Spatial correlation between areas with high risk of contaminated water and areas with the worst quality of life, indicates
the importance of controlling chemical contamination, and demands improvements in the public water supply network and revision
of the theory of social vulnerability. 相似文献
456.
Michael Pryke 《Geoforum》2007,38(3):576-588
The paper adopts a cultural economy approach to explore the emergence of a market in so-called weather derivatives, referred to in the paper as a form of ‘geomoney’. These are specially designed financial products that allow firms to protect their profits against the impact of changing weather conditions. The paper approaches the emergence of this market, and the issues its growth raises, in three interlinked stages. Weather derivatives are located amongst the hybrid collective that is contemporary finance and are analysed through the conceptual apparatus afforded by a cultural economy approach to finance. The paper employs this analytical line to examine the assumptions and models that enable the weather to be turned into a risk and then be transported and traded within capital markets. Through specific examples of weather products together with a discussion of the International Finance Corporation’s recent involvement in this market, the paper suggests something of the ‘world making’ capabilities of finance theory and the politics of finance often hidden beneath the mathematical models. The paper concludes by highlighting not only the usefulness of a cultural economy of finance to geographers but, in light of the examples discussed, the need for cultural economy to recognise and to engage critically in its analysis the politics that such a conceptual approach to the making of financial markets exposes. 相似文献
457.
介绍了法国雷电监测预警系统AMEO 340和防雷业务管理工作,并借鉴其经验,从做好雷电灾害调查与评估和雷电灾害区划,规划建设雷电灾害监测预警平台和预报平台,实现全省雷电业务集约化发展,开展雷电科学技术研究,建立雷电灾害应急处置机制等方面,探讨如何做好防雷业务工作。 相似文献
458.
This paper contributes to the ongoing debate on the concentration of social service facilities within North American cities. The location quotient and the coefficient of localization are applied to data on Adult Services, Children's Services and psychiatric group homes (residential care facilities) in Metropolitan Toronto. Results demonstrate a high degree of localization in all three categories, particularly the psychiatric, and could be used in the formulation of placement policies to relieve certain areas of the inner city of the social and economic pressures created by group home concentration. 相似文献
459.
460.
中国区域经济发展差异的实证研究与R/S分析 总被引:35,自引:0,他引:35
文章回顾了改革开放以来中国经济发展战略的转变,介绍了吉尼系数,区域经济区位熵和Hausdoeff Index的计算方法。采用GDP指标,运用吉尼系数和区域经济区位熵分析了改革开放以来中国三大地带之间,省区之间的绝对差距和相对差距的变化趋势,而且还运用分形理论和R/S方法研究了中国区域经济发展差异的收敛性,得出的结论如下:(1)无论从绝对差距还是从相对差距上看,自改变开放以来中国三大地带之间或省区之间的经济发展差距都在扩大。(2)1995年所实施的区域协调发展战略在近期内并没有缩小地区之间的发展差距。(3)R/S分析结果表明中国区域经济发展差异在未来20年内将继续扩大。 相似文献