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31.
David Moltz 《Journal of marital and family therapy》1992,18(3):223-223
This is a very upsetting topic we are taking on here. It is a dangerous topic. It is polarizing. It is very, very important. 相似文献
32.
Scheduling Updates of Probabilistic Risk Assessments: The Arkansas Nuclear One-Unit 1 Experience 总被引:1,自引:0,他引:1
This paper presents the results of a study that identified how often a probabilistic risk assessment (PRA)should be updated to accommodate the changes that take place at nuclear power plants. Based on a 7-year analysis of design and procedural changes at one plant, we consider 5 years to be the maximum interval for updating PRAs. This conclusion is preliminary because it is based on the review of changes that occurred at a single plant, and it addresses only PRAs that involve a Level 1 analysis (i.e., a PRA including calculation of core damage frequency only). Nevertheless, this conclusion indicates that maintaining a useful PRA requires periodic updating efforts. However, the need for this periodic update stems only partly from the number of changes that can be expected to take place at nuclear power plants–changes that individually have only a moderate to minor impact on the PRA, but whose combined impact is substantial and necessitates a PRA update. Additionally, a comparison of two generations of PRAs performed about 5 years apart indicates that PRAs must be periodically updated to reflect the evolution of PRA methods. The most desirable updating interval depends on these two technical considerations as well as the cost of updating the PRA. (Cost considerations, however, were beyond the scope of this study.) 相似文献
33.
An important characteristic of high-tech industries is decreasing component prices over time. In the personal computer industry, some component prices decline at a rate of 1% per week. This paper develops an inventory model for products experiencing continuous decrease in unit price. We develop an accurate closed-form approximate solution to the model. Our results indicate that declining prices lead to substantial decrease in the optimal cycle time and much frequent ordering. This explains the heavy emphasis on just-in-time inventory management practiced by successful companies in high-tech industries. While previous models attributed the success of just-in-time policies to reduced holding cost and improved quality, under declining prices a substantial source of savings becomes lower costs of raw materials which is significant part of cost in these industries. We illustrate the results of the model with a numerical example and perform sensitivity analysis. 相似文献
34.
David L. Burton 《Child and Adolescent Social Work Journal》2003,20(4):277-296
Veneziano, Veneziano and LeGrand (2000) found support for the victim to victimizer hypothesis of sexual aggression with 74 sexually abusive youth. This project, a further step in examining this theory (Burton, 2000, Burton, Miller, & Shill, 2002) builds on their ideas with data from 179 adolescent sexual abusers, and supports their findings. In an examination of relationships, gender, modus operandi, and acts, the sexually abused youth were likely to repeat what was done to them. This project also offers a further analysis of how victimization accounts for a significant portion of the variance in perpetration by these youth. Implications for research and practice are offered. 相似文献
35.
Sangun Park 《Statistical Papers》2005,46(2):293-301
This article gives a simple result for the expression of the Fisher information in order statistics. This result enables us
to calculate easily the Fisher information in any set of order statistics whose details have been known to be messy and complicated.
We consider here its application in the optimal spacing problem where the exact Fisher information in order statistics has
been approximated with the asymptotic information or the reciprocal of the variance of a suitable estimator.
This work was supported by Korea Research Foundation Grant(KRF-2000-015-DP0056) 相似文献
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Many studies have shown that multinational firms pay more than domestic firms in Third World countries. Economists who criticize
sweatshops have responded that multinational firms’ wage data do not address whether sweatshop jobs are above average because
many of these jobs are with domestic subcontractors. We compare apparel industry wages and the wages of individual firms accused
of being sweatshops to measures of the standard of living in Third World economies. We find that most sweatshop jobs provide
their workers an above average standard of living.
The authors thank Jeffery Hummel, Charles Murray, Larry Pratt, and Edward Stringham for helpful comments on earlier drafts.
Financial support from the American Institute for Economic Research is gratefully acknowledged. The usual disclaimer applies. 相似文献
39.
A Lotto Systems bet allows the player to nominate n numbers from which (s)he believes the winning six numbers will be drawn, and to bet on all combinations of six of these n numbers. Assume that the winning six numbers come from the nominated n. How many combinations must be entered to guarantee that one combination will include at least five of the winning six numbers? The problem is generalized in this paper, and the method of simulated annealing is used to find solutions for various situations. The case where two supplementary numbers are drawn after the initial six winning numbers is also considered. 相似文献
40.
David A. Cotter 《Rural sociology》2002,67(4):534-555
Abstract Accounts of poverty generally fall into either “individualist” or “structuralist” camps. Often these are seen as irreconcilable and incompatible competing perspectives. This paper integrates individualist and structuralist accounts of poverty by examining the relationship between “person poverty” and “place poverty” in nonmetropolitan and metropolitan labor markets, using a multilevel framework. I fashion a general model of poverty production and allocation, drawing on the labor market ecology perspective. After a discussion of this perspective, I develop a multilevel framework for analyzing data from the 1990 Census PUMS‐L sample, STF‐3c, and other sources to show how compositional and contextual factors affect households' likelihoods of being in poverty. These multilevel models also allow us to estimate the degree to which labor market conditions influence the magnitude of household labor supply characteristics. Results suggest that both compositional and contextual factors contribute to the metro‐nonmetro difference in poverty rates, and that the effects of employment vary in accordance with labor market characteristics. 相似文献