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41.
Projecting losses associated with hurricanes is a complex and difficult undertaking that is wrought with uncertainties. Hurricane Charley, which struck southwest Florida on August 13, 2004, illustrates the uncertainty of forecasting damages from these storms. Due to shifts in the track and the rapid intensification of the storm, real-time estimates grew from 2 to 3 billion dollars in losses late on August 12 to a peak of 50 billion dollars for a brief time as the storm appeared to be headed for the Tampa Bay area. The storm hit the resort areas of Charlotte Harbor near Punta Gorda and then went on to Orlando in the central part of the state, with early poststorm estimates converging on a damage estimate in the 28 to 31 billion dollars range. Comparable damage to central Florida had not been seen since Hurricane Donna in 1960. The Florida Commission on Hurricane Loss Projection Methodology (FCHLPM) has recognized the role of computer models in projecting losses from hurricanes. The FCHLPM established a professional team to perform onsite (confidential) audits of computer models developed by several different companies in the United States that seek to have their models approved for use in insurance rate filings in Florida. The team's members represent the fields of actuarial science, computer science, meteorology, statistics, and wind and structural engineering. An important part of the auditing process requires uncertainty and sensitivity analyses to be performed with the applicant's proprietary model. To influence future such analyses, an uncertainty and sensitivity analysis has been completed for loss projections arising from use of a Holland B parameter hurricane wind field model. Uncertainty analysis quantifies the expected percentage reduction in the uncertainty of wind speed and loss that is attributable to each of the input variables. 相似文献
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The extent to which 4‐month attentional regulation during an infant‐mother still‐face situation and 12‐month attachment security during the Strange Situation predicted rates of compliance and noncompliance during a cleanup task at 36 months was examined longitudinally in 70 infant‐mother dyads. Hierarchical multiple regression analyses indicated that infants who showed more attentional regulation during the still‐face situation with mothers later showed a higher rate of committed compliance and a lower rate of situational compliance during cleanup with mothers. Furthermore, lower levels of attentional regulation were later associated with higher rates of assertive behavior, but only for infants in an insecure attachment relationship. 相似文献
44.
本文以二甘醇代替其它多元醇与已二酸反应合成聚酯多元醇 ,再以合适的OH/NCO比与二异氰酸酯TDI生产聚氨酯胶粘剂 .成本低 ,各项粘接性能达到或超过同类产品 .同时利用了制备乙二醇时的副产品二甘醇 ,一举数得 相似文献
45.
首先阐述熊彼特的创新理论 ,指出其不足之处 ,继而阐明研究企业创新体系的必要性 ,最终从企业发展的命题出发 ,提出了企业创新与企业发展、企业创新与经营资源、企业创新与企业核心能力等企业创新体系研究的思路框架 相似文献
46.
The frequency of occupational accidents in fishery is high in most fishery nations. Implementation of safety measures has, however, been limited. The purpose of the present cross-sectional study was to explore Swedish fishermen's attitudes towards occupational risks and accident control. Information was acquired through a questionnaire distributed to a convenience sample of 92 fishermen. Indices were built, containing variables relevant to perceived risk levels in connection with work, perceived manageability of risks, activity in safety work, technical knowledge and individual attitudes towards risks. The results did not support earlier findings of low risk awareness and risk acceptance among fishermen. Perceived manageability of risks but not perceived risk level, accident experience or risk acceptance, were significantly associated with activity in safety work. The results suggest that safety work might benefit from efforts to develop fishermen's understanding of how the development of hazardous situations can be prevented or managed. The results do not support strategies for accident control in fishery based solely on increasing risk awareness. 相似文献
47.
The physical and psychological effects of Turner's Syndrome, a female sex chromosome abnormality, briefly are described. Principles for helping women master the special challenges posed by the disorder are discussed. The authors argue that women with TS must take control of defining their identities and potential in order to attain full status within society. 相似文献
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Cathryn L. Booth K. Alison Clarke‐Stewart Deborah Lowe Vandell Kathleen McCartney Margaret Tresch Owen 《Journal of marriage and the family》2002,64(1):16-26
Mothers' time‐use patterns were compared in families in which infants spent more than 30 hours per week in child care (In‐Care group; n= 143) versus 0 hours per week (At‐Home group; n= 183) from birth to 6 months of age. In‐Care group mothers spent about 12 fewer hours per week interacting with their infants, for about 32% less time; fathers of these infants were more involved in caregiving. The groups did not differ in the quality of mother‐infant interaction. In the In‐Care group, quantity of interaction was related to greater separation anxiety and concerns about effects of maternal employment. Time‐use data were not related to child outcomes at 15 months of age. Results suggest that the effect of extensive time spent apart on the quantity and quality of mother‐infant interaction may be smaller than anticipated. 相似文献
50.