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Five potential sites nominated for the Nation's first geologic repository for disposing of nuclear waste are evaluated using multiattribute utility analysis. The analysis was designed to aid the Department of Energy in its selection of 3 sites for characterization, a detailed data-gathering process that will involve the construction of exploratory shafts for underground testing and that may cost as much as $1 billion per site. The analysis produced insights into the relative advantages and disadvantages of the nominated sites and clarified current uncertainties regarding repository performance.  相似文献   
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The U.S. Department of Energy has selected three sites, from five nominated, to characterize for a nuclear repository to permanently dispose of nuclear waste. This decision was made without the benefit of an analysis of this "portfolio" problem. This paper analyzes different portfolios of three sites for simultaneous characterization and strategies for sequential characterization. Characterization of each site, which involves significant subsurface excavation, is now estimated to cost $1 billion. Mainly because of the high characterization costs, sequential characterization strategies are identified which are the equivalent of $1.7-2.0 billion less expensive than the selected DOE simultaneous characterization of the three sites. If three sites are simultaneously characterized, one portfolio is estimated to be the equivalent of $100-400 million better than the selected DOE portfolio. Because of these potential savings and several other complicating factors that may influence the relative desirability of characterization strategies, a thorough analysis of characterization strategies that addresses the likelihood of finding disqualifying conditions during site characterization, uncertainties, and dependencies in forecast site repository costs, preclosure and postclosure health and safety impacts, potential delays of both sequential and simultaneous characterization strategies, and the environmental, socioeconomic, and health and safety impacts of characterization activities is recommended.  相似文献   
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The American education system is being challenged to raise the academic achievement of students to prepare them for the jobs of the future. Yet many demographic, as well as economic and social factors, are making the task more difficult. Low birth rates, especially among non-Hispanic whites, along with high immigration rates, have increased the share of minority and non-English students in public schools. The rise in single-parent families has increased the number of poor students and migration from the cities to the suburbs has concentrated poor and minority students in inner city schools. These same children will make up a greater share of the future labor force. At the same time, the aging of the general population may lessen the commitment of homeowners- -whose taxes pay between 1/3 and 1/2 of education costs. The aging labor force may bring a shortage of qualified teachers, particularly in specialized subject areas. Poor and minority students generally have below average academic skills and are more likely to drop out of high school than non-minority students. However, the skills of American students rank below those of most other industrialized nations, calling into question the ability of Americans to succeed in an increasingly international economic system. How can schools be improved and minority student achievement be enhanced? Reforms of education finance systems, court-ordered integration, and stiffer requirements for teachers and for graduation from high school are among many attempts to meet the immense challenges faced by American schools.  相似文献   
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This article describes a revised methodology for estimating the current amount of total personal giving in the United States. The previous methodology is evaluated and it is determined that a different methodology, drawing upon recent enrichments in the data on personal giving, would yield improved historical estimates. This would lead to more reliable extrapolations of the current level of giving. Preliminary historical estimates using the new methodology are made for the period 1984 through 1991. These serve as the base for extrapolations to 1992, and results using several extrapolation formulas are compared.The following changes are included in the historical estimates. Changes in the standard deduction strongly affect the decision to itemise deductions and contributions for a large and varying number of habitual contributors. Accordingly, two groups of contributions itemisers — permanent and transitory — were identified and their contributions separately estimated. The estimate of total giving now reflects the different income and contributions levels of each group. Tax return filers who can be taken as dependents on other persons' tax returns (predominantly children of living parents) are excluded from the group of non-itemiser returns. Tax return data on itemised contributions are adjusted using IRS tax return audit findings. A survey-based estimate of the proportion of non-contributos (zero contributors) is used to provide a more accurate count of the number of individuals and families who habitually make contributions but do not itemise them. An estimate is included of the contributions of the large number of low-income individuals and families not in the tax return data as they are not required to file tax returns.The research reported here has received financial support from the American Association of Fund-Raising Counsel Trust for Philanthropy  相似文献   
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The European Communication Monitor (ECM) research explores the current developments for communications disciplines, practices and instruments. It is an extensive research project to monitor trends in communication management, analyse the changing framework for the profession driven by European integration and evaluate specific topics of relevance to public relations practice. Specifically, the 2008 ECM edition is focused on aspects such as: strategy and control, interactive channels, corporate social responsibility, intercultural challenges, influence on management decision making, cooperation with agencies, and future budgets.  相似文献   
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