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Naumann RB Dellinger AM Haileyesus T Ryan GW 《International journal of injury control and safety promotion》2011,18(1):65-73
As the US population ages, more older adults will face transportation and mobility challenges. This study examines the characteristics and contributing circumstances of nonfatal older adult pedestrian injuries. Data were obtained from the National Electronic Injury Surveillance System-All Injury Programme (NEISS-AIP) for the years 2001 through 2006. Cases included persons aged 65 years and older who were nonfatally injured on a public roadway. The results indicated that on average, an estimated 52,482 older adults were treated in emergency departments each year for nonfatal pedestrian injuries. Falling and being hit by a motor vehicle were the leading mechanisms of injury, resulting in 77.5% and 15.0% of older adult pedestrian injuries, respectively. More than 9000 older pedestrian fall-related injuries each year involved a kerb. It is concluded that the growth in the older adult population could add to the overall burden of these nonfatal pedestrian injuries. Making transportation and mobility improvements, including environmental modifications, is important for preventing these injuries. 相似文献
985.
Over 90 percent of companies are estimated to use IT Service Management (ITSM) frameworks, yet there is little research on
their benefits to the Information Technology (IT) department and the business units. An international survey of 491 firms
was conducted to assess the benefits of the IT Infrastructure Library (ITIL), the de-facto ITSM framework, specifically on
how these benefits evolve as companies increase their adoption of the ITIL model. Also studied are the perception of challenges
of the implementation and the number of ITIL processes implemented in relation to the progress of the adoption of ITIL. Results
indicate that as the maturity of implementation increases, the perception of challenges decreases. Findings also show that
as the maturity of implementation increases, the number of realized benefits increases, as well as the number of implemented
ITIL processes. Implications for practitioners and researchers are also discussed. 相似文献
986.
987.
988.
Joshua D. Woodard Nicholas D. Paulson Dmitry Vedenov Gabriel J. Power 《Agricultural Economics》2011,42(Z1):101-112
A number of problems in agricultural economics involve modeling joint distributions for which the assumption of multivariate normality may not be warranted. Yet, very little work has been conducted evaluating competing methods for modeling joint dependence. We develop a simulation framework to evaluate the bias and efficiency impacts of copula choice in the context of evaluating county‐to‐farm basis risk. The results suggest significant differences in performance across various copulas and approaches. The findings have important implications for risk analysis, insurance, and policy modeling problems in agriculture regarding the selection of method to model dependence among random variables. 相似文献
989.
Pierre Mérel 《Journal of Agricultural Economics》2011,62(3):585-603
This article explores the economic efficiency of a horizontally and vertically coordinated industry where upstream producers are atomised, but downstream processors are few, explicitly considering participation incentives and allowing the coordinated industry to exert market power towards buyers. The model offers insight into the probable social impacts of the government‐sanctioned supply control scheme in place in the French Comté cheese market, suggesting it falls short of constituting a Pareto‐improvement compared with a laissez‐faire situation. More generally, our theoretical model provides guidance to identify instances where encouraging industry coordination may be socially desirable. We formally introduce the concept of ‘seller‐equivalent degree of overall market power’ of the separated industry, a market characteristic comprised of measurable or inferable parameters, the value of which is shown to determine the potential for Pareto improvements through industry integration. 相似文献
990.
The rapid urbanization in developing countries implies an increasing pressure on urban agriculture for production. As most perishable food products come from this agriculture in close proximity to population concentrations, we analysed from an agronomic point of view how market-garden farmers can meet this increasing urban demand. This work took place in the case of Mahajanga, a secondary city with high increasing demographic rate on the Northwest coast of Madagascar. Based on preliminary surveys to characterize the farming systems (on a sample of 91 farms), 11 market-garden farmers chosen in the three main agricultural zones of the urban area were surveyed during two years. Surveys aimed at understanding their decision rules in crop choices, crop allocation to land and resource management, and to estimate their room for manoeuvre to increase their leafy vegetable areas under cultivation. The wholesalers and retailers who buy the farmers’ produce were also surveyed. A previous model of decision rules regarding crop location on farm territory was used to analyse the on-farm surveys and cartographic methods (GIS and on-farm manual representations) were used to quantify the land use. We highlight the following major points. (1) The leafy vegetable production in the surveyed farms already intensively uses land: farmers have complex decision rules largely depending on the water dynamics in the two main environments (lowlands and lakesides) where leafy vegetables are cultivated during the dry season. (2) The scarcity of farmers’ resources (labour money and water) leads to very little internal room for manoeuvre to increase the leafy vegetable production in the farms. (3) At territorial level however, some land reserve exist in one of the lowlands, but not on lakesides. The water availability for agriculture must be better informed through specialized hydrologic studies, as one of the main constraints nowadays to extend the agricultural area. An extrapolation to other cases of urban agriculture is then discussed as well as the role of agronomy to help urban planners to consider the place of agriculture in the urban development. 相似文献