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Falls from publicly owned climbing equipment are often cited as the major cause of injury on children's outdoor playgrounds and have been the focus of substantial interventions in the UK since the early 1980s. Analysis of national data on falls from climbing frames for 1988 to 2002 shows that the main discernible trend during this period is an increase in the occurrence of injuries to the lower arm. Whether this is attributable to a behavioural response to some of the interventions, or to some other factor, is unknown.  相似文献   
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With consumers and their activities routinely visible through online, mobile and social media, to both their peers and to corporations, this article examines surveillance as a marketplace icon. Surveillance is central to the construction of consumers and markets. Many contemporary marketing practices are surveillant as they rely on the collection, analysis and application of consumer data to place advertising, define market segments and to nudge consumer behaviours. Consumer surveillance is also an enactment of corporate power, attempting to align individual preferences with corporate goals. The historical origins of surveillance and the emergence of the surveillance–industrial–entertainment complex are explored, which highlights how surveillance, as well as a process for defining markets is also an object of consumption. The future sees a huge struggle for consumer data between two great centres of surveillance power – the state and the corporation – as they battle over data use for national security.  相似文献   
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This study set out to examine environmental factors impacting on the food literacy of adolescents. It utilized data from a nation‐wide survey of home economics teachers regarding their experience of food literacy education in Australian high schools. Content analysis and the ANGELO framework were applied to analyse free‐text comments from 78 of the respondents that were collected as part of a more extensive data set. The analysis of environmental factors revealed three enablers and ten barriers that could influence food literacy education delivered by high schools in Australia. High schools are well positioned to improve adolescents’ food literacy through a comprehensive, hands‐on approach in home economics. However, many environmental barriers were reported that could influence food literacy education in Australian high schools such as: lack of teaching materials and facilities, and human resources; the perceived inadequacy of the Australian school curriculum; non‐supportive school canteens; and negative role modelling. This study points to the need to eliminate or reduce these environmental barriers impacting on the capacity for effective food literacy education in high schools to help adolescents increase their food literacy and thereby support them in making informed food choices.  相似文献   
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When policies are changed, it is not uncommon for losers to be compensated. Economic theory and quantitative analysis are useful in determining the efficiency gains/losses associated with a policy change, but are little help in deciding what the approach to compensation should be. The amount of compensation varies, depending on, in part, the political clout of the parties being negatively affected by a policy change—compensation is what politicians and the sector demanding compensation can agree on. We formulate four approaches to producer compensation within the context of the Ontario Tobacco Transition Program, where producers would have suffered losses in the absence of compensation. The approaches range from providing zero compensation to providing compensation based on the entire value of the tobacco quota. The Canadian government chose the latter and compensated producers for the termination of the tobacco quota program based on an approach that far exceeded other possible compensation approaches.  相似文献   
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Adverse weather is the dominant cause of delays in the National Airspace System (NAS). Since the future weather condition is only predictable with a certain degree of accuracy, managing traffic in the weather-affected airspace is a challenging task. In this paper, we propose a geometric model to generate an optimal combination of ground delay and route choice to hedge against weather risk. The geometric recourse model (GRM) is a strategic Probabilistic Air Traffic Management (PATM) model that generates optimal route choice, incorporating route hedging and en-route recourse to respond to weather change: hedged routes are routes other than the nominal or the detour one, and recourse occurs when the weather restricted airspace becomes flyable and aircraft are re-routed to fly direct to the destination. Among several variations of the GRM, we focus on the hybrid Dual Recourse Model (DRM), which allows ground delay as well as route hedging and recourses, when the weather clearance time follows a uniform distribution. The formulation of the hybrid DRM involves two decision variables - ground delay and route choice - and four parameters: storm location, storm size, maximum storm duration time, and ground-airborne cost ratio. The objective function has two components: expected total ground delay cost and expected total airborne cost. We propose a solution algorithm that guarantees to find the global optimum of the hybrid-DRM. Based on the numerical analysis, we find that ground-holding is effective only when combined with the nominal route. Otherwise, it is optimal to fly on the route determined by the DRM without ground delay. We also find the formula of the threshold ground-airborne cost ratio, which we call the Critical Cost Ratio (CCR), that determines the efficacy of ground delay: the higher the CCR, the more effective the strategies involving ground delay. We conclude that both ground delay and route hedging should be considered together to produce the best ATM decisions.  相似文献   
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Cocoa and coffee are the most important crops in Côted'Ivoire. Until recently, the difference between world and administeredproducer prices provided an important source of government revenue.As a result of a continued decline of world prices of both crops,however, the Ivoirien government was forced to cut producerprices in half. Because 40 percent of Ivoirien households groweither cocoa or coffee, this cut can be expected to have a considerableimpact on the welfare level of these households. We use the1985 Living Standards Measurement Survey to estimate the welfareeffects of producer price changes for Ivoirien households, permittingan evaluation of the probable consequences of the recent pricecut. Using nonparametric econometric techniques, we find that,although many households will suffer losses of income, the cutswill not have adverse distributional effects: cocoa and coffeefarmers are scattered throughout the income distribution, butmost are concentrated in the middle.  相似文献   
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Generally small schemes are more beneficial than large schemes, with fewer management and money problems. An attempt is made to analyse the components of large and small irrigation developments in order to expose and compare the causes of success or failure.  相似文献   
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