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221.
Nuclear Waste Management under Approaching Disaster: A Comparison of Decommissioning Strategies for the German Repository Asse II 下载免费PDF全文
This article compares different strategies for handling low‐ and medium‐level nuclear waste buried in a retired potassium mine in Germany (Asse II) that faces significant risk of uncontrollable brine intrusion and, hence, long‐term groundwater contamination. We survey the policy process that has resulted in the identification of three possible so‐called decommissioning options: complete backfilling, relocation of the waste to deeper levels in the mine, and retrieval. The selection of a decommissioning strategy must compare expected investment costs with expected social damage costs (economic, environmental, and health damage costs) caused by flooding and subsequent groundwater contamination. We apply a cost minimization approach that accounts for the uncertainty regarding the stability of the rock formation and the risk of an uncontrollable brine intrusion. Since economic and health impacts stretch out into the far future, we examine the impact of different discounting methods and rates. Due to parameter uncertainty, we conduct a sensitivity analysis concerning key assumptions. We find that retrieval, the currently preferred option by policymakers, has the lowest expected social damage costs for low discount rates. However, this advantage is overcompensated by higher expected investment costs. Considering all costs, backfilling is the best option for all discounting scenarios considered. 相似文献
222.
Patrick Murigu Kamau Njage Clementine Henri Pimlapas Leekitcharoenphon Michel‐Yves Mistou Rene S. Hendriksen Tine Hald 《Risk analysis》2019,39(6):1397-1413
Next‐generation sequencing (NGS) data present an untapped potential to improve microbial risk assessment (MRA) through increased specificity and redefinition of the hazard. Most of the MRA models do not account for differences in survivability and virulence among strains. The potential of machine learning algorithms for predicting the risk/health burden at the population level while inputting large and complex NGS data was explored with Listeria monocytogenes as a case study. Listeria data consisted of a percentage similarity matrix from genome assemblies of 38 and 207 strains of clinical and food origin, respectively. Basic Local Alignment (BLAST) was used to align the assemblies against a database of 136 virulence and stress resistance genes. The outcome variable was frequency of illness, which is the percentage of reported cases associated with each strain. These frequency data were discretized into seven ordinal outcome categories and used for supervised machine learning and model selection from five ensemble algorithms. There was no significant difference in accuracy between the models, and support vector machine with linear kernel was chosen for further inference (accuracy of 89% [95% CI: 68%, 97%]). The virulence genes FAM002725, FAM002728, FAM002729, InlF, InlJ, Inlk, IisY, IisD, IisX, IisH, IisB, lmo2026, and FAM003296 were important predictors of higher frequency of illness. InlF was uniquely truncated in the sequence type 121 strains. Most important risk predictor genes occurred at highest prevalence among strains from ready‐to‐eat, dairy, and composite foods. We foresee that the findings and approaches described offer the potential for rethinking the current approaches in MRA. 相似文献
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Patrick Walsh Galen Clavio Susan Mullane Warren Whisenant 《Public Organization Review》2014,14(2):127-138
Due to the growth of the video game industry, the practice of in-game advertising, and the desirable game player demographics, then U.S. Presidential candidate Barack Obama placed early voting advertisements in a series of online sport video games during his 2008 presidential campaign. The purpose of this study was to examine the awareness of these political ads and the attitudes towards the ads when compared to advertisements featuring corporate brands. The results suggest there were higher levels of awareness for the political themed advertisements while attitude enhancement was more likely to occur for advertisements which featured corporate brands. 相似文献
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Empirical studies have delivered mixed conclusions on whether the widely acclaimed assertions of lower electronic retail (e‐tail) prices are true and to what extent these prices impact conventional retail prices, profits, and consumer welfare. For goods that require little in‐person pre‐ or postsales support such as CDs, DVDs, and books, we extend Balasubramanian's e‐tailer‐in‐the‐center, spatial, circular market model to examine the impact of a multichannel e‐tailer's presence on retailers' decisions to relocate, on retail prices and profits, and consumer welfare. We demonstrate several counter‐intuitive results. For example, when the disutility of buying online and shipping costs are relatively low, retailers are better off by not relocating in response to an e‐tailer's entry into the retail channel. In addition, such an entry—a multichannel strategy—may lead to increased retail prices and increased profits across the industry. Finally, consumers can be better off with less channel competition. The underlying message is that inferences regarding prices, profits, and consumer welfare critically depend on specifications of the good, disutility and shipping costs versus transportation costs (or more generally, positioning), and competition. 相似文献
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This multi-site examination of sexual abuse histories of youth in residential treatment centers asked, for the sample as a whole and by youth's gender: (a) How many perpetrators did each youth have? (b) What was the gender of the perpetrator? (c) What proportion of youth was abused by family members? (d) What proportion of youth was abused in a child welfare setting? And, (e) what proportion of sexually abused youth were also victims of physical abuse and/or neglect? Results revealed that males were more likely to have one perpetrator, a female perpetrator, and to have been abused in a child welfare setting and less likely be abused by a family member. Implications for refining programs and practices are discussed. 相似文献
229.
While more and more firms have implemented e‐business in business operations, a better understanding of the factors that successfully drive the assimilation of e‐business will provide insights for firm executives and practitioners to develop effective strategies for e‐business. Different from previous studies that focus on individual‐level factors related to business executives and top management teams, this study examines how firm‐level strategic and cultural factors shape e‐business assimilation. Based on the strategy and marketing literature on market orientation and firm ownership, we developed a research model to describe how a firm's market orientation impacts e‐business assimilation. The model also describes the moderating effect of firm ownership type on the relationship between market orientation and e‐business assimilation. Based on data from 301 Chinese international trade firms, we found that two dimensions of market orientation (i.e., customer orientation, competitor orientation) had significant effects on e‐business assimilation. However, the third dimension, interfunctional coordination, was only partially significant. In addition, ownership type was a significant moderator of the effects of customer orientation and competitor orientation on e‐business assimilation, although ownership type was not a moderator of interfunctional coordination. Being one of the first studies of the impact of market orientation and firm ownership type on e‐business assimilation, we conclude with a discussion of the implications for future research and practice. 相似文献
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