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排序方式： 共有8411条查询结果，搜索用时 15 毫秒
21.
Yingqi Zhang 《Greenhouse Gases: Science and Technology》2011,1(2):175-179
For geological CO2 storage site selection, it is desirable to reduce the number of candidate sites through a screening process before detailed site characterization is performed. Screening generally involves defi ning a number of criteria which then need to be evaluated for each site. The importance of each criterion to the fi nal evaluation will generally be different. Weights refl ecting the relative importance of these criteria can be provided by experts. To evaluate a site, each criterion must be evaluated and scored, and then aggregated, taking into account the importance of the criteria. We propose the use of the Choquet integral for aggregating the scores. The Choquet integral considers the interactions among criteria, i.e. whether they are independent, complementary to each other, or partially repetitive. We also evaluate the Shapley index, which demonstrates how the importance of a given piece of information may change if it is considered by itself or together with other available information. An illustrative example demonstrates how the Choquet integral properly accounts for the presence of redundancy in two site‐evaluation criteria, making the screening process more defensible than the standard weighted‐average approach. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd 相似文献
22.
Brian Ellis Catherine Peters Jeffrey Fitts Grant Bromhal Dustin McIntyre Robert Warzinski Eilis Rosenbaum 《Greenhouse Gases: Science and Technology》2011,1(3):248-260
A flow‐through experiment was performed to investigate evolution of a fractured carbonate caprock during flow of CO2‐acidified brine. A core was taken from the Amherstburg limestone, a caprock formation overlying the Bois Blanc and Bass Islands formations, which have been used to demonstrate CO2 storage in the Michigan basin. The inlet brine was representative of deep saline brines saturated with CO2, resulting in a starting pH of 4.4. Experimental conditions were 27 °C and 10 MPa. X‐ray computed tomography and scanning electron microscopy were used to observe evolution of fracture geometry and to investigate mineralogical changes along the fracture surface. The initial brine flow corresponded to an average fluid velocity of 110 cm hr−1. After one week, substantial mineral dissolution caused the average cross‐sectional area of the fracture to increase from 0.09 cm2 to 0.24 cm2. This demonstrates that carbonate caprocks, if fractured, can erode quickly and may jeopardize sealing integrity when hydrodynamic conditions promote flow of CO2‐acidified brine. However, changes to fracture permeability due to mineral dissolution may be offset by unaltered constrictions along the flow path and by increases in surface roughness. In this experiment, preferential dissolution of calcite over dolomite led to uneven erosion of the fracture surface and an increase in roughness. In areas with clay minerals, calcite dissolution left behind a silicate mineral‐rich microporous coating along the fracture wall. Thus, the evolution of fracture permeability will depend in a complex way on the carbonate content, as well as the heterogeneity of the minerals and their spatial patterning. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd 相似文献
23.
Alan J. Gross 《Environmetrics》1995,6(4):403-412
The United States Environmental Protection Agency (EPA), in its recent risk assessment dealing with environmental tobacco smoke (ETS), estimated the annual number of lung cancer deaths in non-smokers (including both never-smokers and former-smokers who have quit smoking for at least five years) associated with ETS exposure to be between 2500 and 3300 in the United States. This estimate is based on a number of assumptions that are not supported by the existing data. Moreover, the range presented by EPA fails to take into account the uncertainties involved in this estimate. This paper discusses the significant assumptions that underlie any quantitation of lung cancer risks allegedly due to ETS exposure, and explores the uncertainties of each assumption and how each uncertainty affects the summary estimate. The author concludes that any range must encompass an estimate of zero deaths, and that the uncertainties are so great as to cast serious doubt on the use of any quantitative estimate. 相似文献
24.
The classical problem of pooling data of two independent random samples drawn possibly from two identical arbitrary populations is considered. Decision to pool the two samples or not is based on the outcome of the preliminary test and then a shrinkage technique is used. In an asymptotic setup, the distributional risks of the proposed estimators are derived and compared. This study reveals the robustness property of the proposed shrinkage preliminary test maximum likelihood estimator (SPTMLE) when the assumed restraints may not hold. It is shown that the proposed estimator provides a wider range than the usual preliminary test maximum likelihood estimator (PTMLE) in which it dominates the classical estimator. More importantly, the SPTMLE provides more meaningful size for the preliminary test. 相似文献
25.
Lasse Wallquist Vivianne H. M. Visschers Simone Dohle Michael Siegrist 《Greenhouse Gases: Science and Technology》2011,1(1):83-91
Public perceptions of the benefits and risks associated with carbon dioxide capture and storage (CCS) are important determinants of public acceptance and have a strong impact on the political feasibility of this technology. Communication material aimed at informing the general public about CCS should be tested to find out how it influences perceived risks and benefits. Existing literature shows that laypeople's intuitive concepts about technical functioning and value‐based socio‐economic concerns influence perceived risks and benefits. We conducted two experimental studies that built on previous research about lay concepts of CCS. The first experiment examined the impact of extensive information versus basic information; the second experiment examined the effect of specific information on perceived risks and benefits. The results show that the provision of comprehensive information aimed at resolving prevalent misconceptions about CCS can decrease perceived risk and increase perceived benefits. But the findings also show that some specific types of information can result in the perception of higher risks and lower benefits. We conclude that CCS communication for the general public needs to be adapted to laypeople's intuitive knowledge in associated fields. The present research provides some first indications of how specific information about CCS can affect the public. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd 相似文献
26.
海伦地区水热耦合特征及其对大豆产量的影响 总被引：1，自引：0，他引：1
农业是受气候变化影响的主要敏感行业之一,气候变暖带来的气温升高以及降水格局的改变对农作物生产有利有弊。论文基于黑龙江海伦地区1978—2004年生长季≥10℃有效积温、降水量和统计年鉴中的大豆产量数据,以积温和降水在季节上的匹配程度作为判断水热耦合的指标,采用气候波动指数、减产风险指数作为大豆产量受气候波动影响程度的指标,研究了在生长季降水量下降和≥10℃有效积温增加的趋势下水热耦合的年际和年内变化特征及其对大豆产量的影响,并分析了偏干旱、正常和湿润年份大豆产量受气候波动影响的特征和减产风险性。结果表明,大豆气候波动指数和产量减产风险指数从大到小均依次为偏干旱年、偏湿润年和正常年,说明海伦地区受气候暖干化影响较大。 相似文献
27.
通过对我国新旧《生活饮用水卫生标准》和国外饮用水卫生标准的差别比较,结合对国际上发达国家的饮用水卫生标准发展趋势的探讨;表明新的《生活饮用水卫生标准》(GB5749-2006)更具先进性,与国际标准接轨;同时其可操作性更强,又与我国国情贴近。 相似文献
28.
Sagoff [Journal of Agricultural and Environmental Ethics 18 (2005), 215–236] argues, against growing empirical evidence, that major environmental impacts of non-native species are
unproven. However, many such impacts, including extinctions of both island and continental species, have both been demonstrated
and judged by the public to be harmful. Although more public attention has been focused on non-native animals than non-native
plants, the latter more often cause ecosystem-wide impacts. Increased regulation of introduction of non-native species is,
therefore, warranted, and, contra Sagoff’s assertions, invasion biologists have recently developed methods that greatly aid prediction of which introduced
species will harm the environment and thus enable more efficient regulation. The fact that introduced species may increase
local biodiversity in certain instances has not been shown to result in desired changes in ecosystem function. In other locales,
they decrease biodiversity, as they do globally. 相似文献
29.
Jason Chi‐hin Chan Richard Welford 《Corporate Social Responsibility and Environmental Management》2005,12(2):88-104
Due to its large population, rapid economic growth and the fragility of its environment, China is environmentally more risky than Western countries. Over time we will see tougher and better‐implemented environmental regulations in China. At the same time, sound environmental management is being viewed by investors as an essential part of good corporate governance. Hong Kong listed companies have failed to provide sufficient information for investors to assess their positions with respect to environmental management. This increases their vulnerability to possible accusations of poor environmental performance. The lack of environmental activity and accountability identified amongst the companies leads us to conclude that they are taking substantial yet avoidable risks. In the short term, Hong Kong security market regulators should expedite better voluntary environmental reporting. In the long term, a fundamental reform of security regulations in partnership between regulators, professionals and listed companies should be pursued. Copyright © 2005 John Wiley & Sons, Ltd and ERP Environment. 相似文献
30.
In this paper, we study empirically whether uncertainty has an influence on trade in the US sulfur dioxide allowances market.
In particular, we investigate the role of uncertainty on banking behavior. To do this, we introduce a tractable, structural
model of trading permits under uncertainty. The model establishes a relation between banking behavior and risk preferences,
especially prudence in the Kimball (1990) sense. We then test this model using data on allowances, for utilities submitted to the US Environmental Protection Agency’s
Acid Rain Program, carried over from one year to the next. Evidence is found of imprudence, namely, utilities bank permits
in order to favor higher profits. Another finding is that larger utilities do not adopt behavior significantly different from
that of smaller ones.
This paper was presented at the “International Workshop on Uncertainty in Greenhouse Gas Inventories: Verification, Compliance
& Trading” in Warsaw, Poland, September 2004, under the title “Portfolio Management of Emissions Permits and Prudence Behavior.” 相似文献