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691.
Knowledge on failure events and their associated factors, gained from past construction projects, is regarded as potentially extremely useful in risk management. However, a number of circumstances are constraining its wider use. Such knowledge is usually scarce, seldom documented, and even unavailable when it is required. Further, there exists a lack of proven methods to integrate and analyze it in a cost‐effective way. This article addresses possible options to overcome these difficulties. Focusing on limited but critical potential failure events, the article demonstrates how knowledge on a number of important potential failure events in tunnel works can be integrated. The problem of unavailable or incomplete information was addressed by gathering judgments from a group of experts. The elicited expert knowledge consisted of failure scenarios and associated probabilistic information. This information was integrated using Bayesian belief‐networks‐based models that were first customized in order to deal with the expected divergence in judgments caused by epistemic uncertainty of risks. The work described in the article shows that the developed models that integrate risk‐related knowledge provide guidance as to the use of specific remedial measures.  相似文献   
692.
Predicting the human‐health effects of reducing atmospheric emissions of nitrogen oxide (NOx) emissions from power plants, motor vehicles, and other sources is complex because of nonlinearity in the relevant atmospheric processes. We estimate the health impacts of changes in fine particulate matter (PM2.5) and ozone concentrations that result from control of NOx emissions alone and in conjunction with other pollutants in and outside the mega‐city of Shanghai, China. The Community Multiscale Air Quality (CMAQ) Modeling System is applied to model the effects on atmospheric concentrations of emissions from different economic sectors and geographic locations. Health impacts are quantified by combining concentration‐response functions from the epidemiological literature with pollutant concentration and population distributions. We find that the health benefits per ton of emission reduction are more sensitive to the location (i.e., inside vs. outside of Shanghai) than to the sectors that are controlled. For eastern China, we predict between 1 and 20 fewer premature deaths per year per 1,000 tons of NOx emission reductions, valued at $300–$6,000 per ton. Health benefits are sensitive to seasonal variation in emission controls. Policies to control NOx emissions need to consider emission location, season, and simultaneous control of other pollutants to avoid unintended consequences.  相似文献   
693.
The paper is devoted to the analytic theory of differential equations.In paper shown that how to establish the analytical properties of solutions of an autonomous system of the third order special type(meromorphy of general solutions,instances of availability logarithmic branch points).The method for constructing the first integrals of the systems under consideration is indicated.  相似文献   
694.
Research has shown that defence spending has repercussions on government policies and economic growth. At an international scale these implications, together with current financial difficulties affecting governments, justify the timeliness and interest of studying defence policies from the standpoint of efficiency. Many authors and international bodies such as NATO consider Life Cycle Costing (LCC) the best model for improving the efficiency of military investments. This paper examines the political repercussions in different countries of introducing the LCC model. The research methodology is based on a questionnaire that was replied to by the defence departments of 28 countries, classified as developing or developed.  相似文献   
695.
We investigate the association between the intensity of causal reasoning on performance in a firm’s annual management commentary and its earnings management propensity. Anticipated earnings management concerns are argued to constitute a significant accountability predicament, bringing management to offer more intense causal reasoning in order to mitigate investors’ earnings management concerns. We use computer-intensive techniques to measure causal reasoning intensity as a generic disclosure quality in the management commentary of a large sample of US firms from 1999 to 2007. We find that accruals earnings management (signed discretionary accruals) is positively associated with causal reasoning intensity. The positive association holds for alternative specifications of accruals earnings management (an earnings management dummy model and an analyst expectations model) and in a change model. Our results are consistent with the assertion that firms strategically use causal reasoning on performance to establish appropriateness and cognitive legitimacy, increase perceived plausibility of reported performance and mitigate performance-related concerns of investors.  相似文献   
696.
This paper focuses on four recent United States Supreme Court decisions which have profound implications for political redistricting. These cases are Holder v. Hall, Johnson v. De Grandy, Shaw v. Reno and Miller v. Johnson. Each of these cases place limits on the scope of Section 2 of the Voting Rights Act when conducting a political redistricting or fashioning a remedy for a Section 2 violation. These cases have resolved a number of important issues in redistricting while creating yet new issues to be resolved. Although demographers are not in the business of practicing law, they must clearly understand the legal requirements and often subtle nuances imposed by the case law. The paper concludes that the combined force of these cases does not yet spell the end of race conscious redistricting and therefore, effectively repeal the Voting Rights Act but does require that more weight be given to traditional redistricting criteria when designing districts that will withstand legal challenges.  相似文献   
697.
This study examines patterns of male migration in central Italy during its transformation from an agrarian to an urban-industrial society. The Italian population registers provide data on the extent and type of emigration among more than 3,500 men (ages 10 and over) who immigrated to the commune of Casalecchio di Reno, bordering the city of Bologna, from 1865 to 1915. Demographic and social differentials in overall rates of emigration and their relation to places of origin and destination are measured. The implications of these results for an understanding of population mobility are discussed.  相似文献   
698.
The purpose of this paper is to further the understanding of subjective measures used to assess poverty and to add to the literature on poverty measurement methodology. In particular, the paper focuses on the minimum income question (MIQ) first proposed by Goedhart and colleagues (1977). Data from the U.S. Consumer Expenditure Survey and from a Dutch newspaper survey are used. The primary contribution of the paper is the inclusion of household expenditures as additional explanatory variables of minimally necessary income. Significant differences between the coefficients of several categories of expenditures, particularly for leisure, appear to reveal differences in the interpretation of the minimum income question by respondents. Thus, we question the underlying assumption of the MIQ that everyone adheres the same welfare meaning to the phrase “minimally necessary income,” and conclude that the resulting thresholds should not be used as to measure poverty before further research has been carried out to explore what respondents are thinking when they answer questions such as the MIQ.  相似文献   
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