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61.
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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E. Chiapello 《Sociologie du Travail》2005,47(3):362
In 2002, the European Union changed direction from its past efforts to harmonise European accounting systems and turned instead to a subcontractor, requiring listed European companies to adopt accounting standards drawn up by a private London-based organisation, the IASB (International Accounting Standards Board), which had until then had no public mandate. This decision was all the more significant because the EU has no institutional means of control over the IASB, although it was the first geographical group to decide to impose these standards on its businesses. IASB standards are rooted in the “anglo-saxon” tradition of standardisation for the financial markets, and the view of the enterprise they promote diverges from the accounting traditions of continental European capitalism. This article shows how the new standards are transforming the concept of enterprise, and examines the span of factors that brought about what is a major institutional change for European capitalism. — Special issue: New patterns of institutions. 相似文献
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Rainfall interception by Santa Monica's municipal urban forest 总被引:4,自引:2,他引:2
Effects of urban forests on rainfall interception and runoff reduction have been conceptualized, but not well quantified. In this study rainfall interception by street and park trees in Santa Monica, California is simulated. A mass and energy balance rainfall interception model is used to simulate rainfall interception processes (e.g., gross precipitation, free throughfall, canopy drip, stemflow, and evaporation). Annual rainfall interception by the 29,299 street and park trees was 193,168 m3 (6.6 m3/tree), or 1.6% of total precipitation. The annual value of avoided stormwater treatment and flood control costs associated with reduced runoff was $110,890 ($3.60/tree). Interception rate varied with tree species and sizes. Rainfall interception ranged from 15.3% (0.8 m3/tree) for a small Jacaranda mimosifolia (3.5 cm diameter at breast height) to 66.5% (20.8 m3/tree) for a mature Tristania conferta (38.1 cm). In a 25-year storm, interception by all street and park trees was 12,139.5 m3 (0.4%), each tree yielding $0.60 (0.4 m3/tree) in avoided flood control costs. Rainfall interception varied seasonally, averaging 14.8% during a 21.7 mm winter storm and 79.5% during a 20.3 mm summer storm for a large, deciduous Platanus acerifolia tree. Effects of differences in temporal precipitation patterns, tree population traits, and pruning practices on interception in Santa Monica, Modesto, and Sacramento, California are described. 相似文献
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Sources of drug information among adolescent students 总被引:1,自引:0,他引:1
E Mirzaee P M Kingery B E Pruitt G Heuberger R S Hurley 《Journal of drug education》1991,21(2):95-106
A sample of 1023 eighth and tenth grade students in small to medium-sized central Texas school districts was assessed to determine the amount of information they receive from ten sources about six categories of drugs. The amount of information males reported receiving about each drug category was significantly greater than what females reported, and the amount of information that eighth graders reported receiving about each drug category was significantly greater than what tenth graders reported. Television was the primary source of drug information for all categories of drugs except inhalants, for which friends and television were equally important sources. Parents and printed media (magazines or newspapers) were of secondary importance, followed by friends and teachers. Adolescents were less likely to receive drug-related information from experience, siblings, church, doctors, and police. The reliance on the mass media for drug information in smaller school districts is a pattern which has been previously observed in larger urban districts. This consistency suggests that mass media approaches to drug education are likely to be as effective in rural areas and smaller towns as they are among urban adolescents. Implications for television programming are discussed. 相似文献
70.
This study investigates the extent and nature of housing affordability for elderly nonmetropolitan female heads of household
using data from the Panel Study of Income Dynamics. The results indicate that over one-third of elderly nonmetropolitan female
heads of household experience housing poverty and that those who rent, who have fair to poor health, and who are minorities
are particularly vulnerable. Housing affordability, measured by the concept of housing poverty, identifies households struggling
to meet basic needs while the conventional 25% of income for housing expenditures ratio identifies a larger population. The
findings suggest the need for multifaceted public policies to address the problem of housing poverty.
Her research interests include housing affordability, housing and community vitality, and decision making. She received her
Ph.D. from Purdue University.
Sooyoun Park is in the same department as a Project Assistant on a USDA-funded research project entitled “Housing Affordability
in Rural Areas,” which is a joint project between Nebraska and Wisconsin. Her research interests focus on housing management
behavior in relation to housing expenditure burden. She received her Ph.D. from the University of Nebraska-Lincoln. 相似文献