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951.
On 3-Stage Clos Networks with Different Nonblocking Requirements on Two Types of Calls 总被引:1,自引:0,他引:1
Hwang and Lin introduced a new nonblocking requirement for 2-cast traffic which imposes different requirements on different types of coexisting calls. The requirement is strictly nonblocking for point-to-point calls among the 2-cast traffic, and is rearrangeable for genuine 2-cast calls. They conjectured that the 3-stage Clos network C(n,n,r,r,2n) satisfies the above requirement. We prove that C(n,n,4,r,2n) satisfies the above requirement.Supported in part by NSC91-2115-M009-002.Supported in part by the National Science Council under grant NSC91-2115-M009-010 and by the Li-Li-Tai-Yang Network Research Center of National Chiao Tung University. 相似文献
952.
We address the problem of distributing safety-enhancing devices across a region, where each identical device provides for only local protection of the population. The devices protect nonidentical sectors of the population. The sectors of population are exposed to nonidentical intensities of hazard. A method for the screening and prioritizing of needs for the protective devices is described. An approach of risk-benefit-cost analysis under uncertainty is recommended as follows. Measures of hazard intensity and population exposure are identified. Exogenous parameters that influence assessments of risks, benefits, and costs are identified. Uncertainties of the exogenous parameters are propagated by interval analysis. Several tiers of the plausibility of need for protection are identified. The tiers are useful in setting priorities for the distribution of the safety devices. The method is demonstrated in an engineering application to roadway lighting, but has implications for disaster preparedness, anti-terrorism, transportation safety, and other arenas of public safety. 相似文献
953.
954.
The need to integrate adaptation efforts into land-use planning policies has been only recently recognized in Ho Chi Minh City. The city's latest planning guidance addresses both flooding resilience and mitigation of urban heat. This paper outlines the development contexts and the current barriers for adapted land-use planning within the city. The key challenge for land-use planning is communicating the important functions and services of open and natural urban spaces and effectively guiding the mainly individual developer-driven development. As the realization of non-structural adaptation measures is in strong contrast to the current market-driven private and short-term developer interests, the main development trajectories are questioned and synergies identified. 相似文献
955.
956.
Xenophon Koufteros Cornelia Droge Gregory Heim Nelson Massad Shawnee K. Vickery 《决策科学》2014,45(1):5-48
This study focuses on whether historical satisfaction with an e‐tailer (HSat) moderates baseline relationships in order fulfillment service quality models. HSat is defined as satisfaction with the e‐tailer spanning all transactions except the current encounter. Encounter satisfaction (ESat) is defined as the consumer's satisfaction with the current transaction. In the baseline model, four order fulfillment service quality (OFSQ) dimensions managerially relevant to consumer e‐tailing are examined: timeliness, availability, condition, and billing accuracy. The baseline structural model results support that OFSQ dimensions impact ESat, which in turn predicts two key consequences—repurchase intention and word‐of‐mouth. Adaptation theory is used to model the role of HSat, while controlling for transaction recency, vendor familiarity, and competitive pricing. HSat is shown to have pervasive main and interaction effects upon all baseline model relationships. These moderation effects have great managerial relevance. For example, the results illustrate a phenomenon similar to the service recovery paradox, wherein when a negative service encounter is followed by a highly positive service recovery event, previously dissatisfied consumers, as compared to previously satisfied consumers, respond with higher levels of current satisfaction. For managers, this finding is encouraging because policies that create highly positive events for consumers can thus supersede past negative experiences. Our results show however that HSat cannot be completely superseded by current OFSQ or current ESat. 相似文献
957.
We investigate the relation between customer satisfaction, customer servicing costs, and customer value in a financial services firm. We find that customer satisfaction is positively associated with future customer servicing costs, as well as with customer value. The relation between customer satisfaction and customer value appears non-linear; higher customer satisfaction appears to have a higher return for the most profitable customer segments. Our findings indicate that customer satisfaction is a value driver; however, customer satisfaction is not cost-free and managers have to consider the costs, as well as the benefits, of increasing customer satisfaction. 相似文献
958.
Erkki K. Laitinen 《Long Range Planning》2000,33(6):805-830
This study analyses the success of adaptation strategies applied by Finnish companies during the recession in 1989–93. Five different strategies emerged from data gleaned from a questionnaire answered by 750 companies. In the medium term, investment in new product development and marketing and in the acquisition of new customers was the most successful strategy while a strategy heavily based on negotiating finance contracts and restructuring was the most unsuccessful. To evaluate the long-term effects of adopted strategies, financial statements from 644 companies in 1994 and 1997 were analysed. The results supported the medium-term conclusions. In general, they suggested that in the long-term, active adaptation strategies are most likely to lead to sustained success whereas passive (financial) strategies are associated with a high risk of failure. 相似文献
959.
Risk Estimation and Value-of-Information Analysis for Three Proposed Genetic Screening Programs for Chronic Beryllium Disease Prevention 总被引:1,自引:0,他引:1
Scott M. Bartell Rafael A. Ponce Timothy K. Takaro Richard O. Zerbe Gilbert S. Omenn & Elaine M. Faustman 《Risk analysis》2000,20(1):87-100
Genetic differences (polymorphisms) among members of a population are thought to influence susceptibility to various environmental exposures. In practice, however, this information is rarely incorporated into quantitative risk assessment and risk management. We describe an analytic framework for predicting the risk reduction and value-of-information (VOI) resulting from specific risk management applications of genetic biomarkers, and we apply the framework to the example of occupational chronic beryllium disease (CBD), an immune-mediated pulmonary granulomatous disease. One described Human Leukocyte Antigen gene variant, HLA-DP beta 1*0201, contains a substitution of glutamate for lysine at position 69 that appears to have high sensitivity (approximately 94%) but low specificity (approximately 70%) with respect to CBD among individuals occupationally exposed to respirable beryllium. The expected postintervention CBD prevalence rates for using the genetic variant (1) as a required job placement screen, (2) as a medical screen for semiannual in place of annual lymphocyte proliferation testing, or (3) as a voluntary job placement screen are 0.08%, 0.8%, and 0.6%, respectively, in a hypothetical cohort with 1% baseline CBD prevalence. VOI analysis is used to examine the reduction in total social cost, calculated as the net value of disease reduction and financial expenditures, expected for proposed CBD intervention programs based on the genetic susceptibility test. For the example cohort, the expected net VOI per beryllium worker for genetically based testing and intervention is $13,000, $1,800, and $5,100, respectively, based on a health valuation of $1.45 million per CBD case avoided. VOI results for alternative CBD evaluations are also presented. Despite large parameter uncertainty, probabilistic analysis predicts generally positive utility for each of the three evaluated programs when avoidance of a CBD case is valued at $1 million or higher. Although the utility of a proposed risk management program may be evaluated solely in terms of risk reduction and financial costs, decisions about genetic testing and program implementation must also consider serious social, legal, and ethical factors. 相似文献
960.
Earlier work with decision trees identified nonseparability as an obstacle to minimizing the conditional expected value, a measure of the risk of extreme events, by the well-known method of averaging out and folding back. This first of two companion papers addresses the conditional expected value that is defined as the expected outcome assuming the exceedance of a threshold β, where β is preselected by the decision maker. An approach is proposed to overcome the need to evaluate all policies in order to identify the optimal policy. The approach is based on the insight that the conditional expected value is separable into two constituent elements of risk and can thus be optimized along with other objectives, including the unconditional expected value of the outcome, by using a multiobjective decision tree. An example of sequential decision making for improving highway capacity is given. 相似文献