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Objective: P plates (or decals) identify a driver's license status to other road users. They are a compulsory part of the graduated driver licensing system in Queensland, Australia, for drivers on a P1 (provisional 1) or P2 (provisional 2) license. This study explored the perceptions of young drivers regarding the display of P plates (decals) in Queensland, Australia.

Methods: In this study, 226 young drivers with a provisional (intermediate/restricted) license completed a 30-min online survey between October 2013 and June 2014. t Tests were used to compare the opinions of people who displayed their plates nearly always with those who displayed them less frequently.

Results: Participants approved of the requirement to display P plates with 69% of those on a P1 license and 79% on a P2 license supporting the condition to display P1 (red) plates. Participants on a P1 license (62%) and a P2 license (68%) also approved the requirement to display P2 (green) plates. However, young drivers also perceived that the display of P plates (measured from 1 = never to 5 = nearly all the time) enabled newly licensed drivers to be targeted by police and other drivers (those who do not always display P plates: M = 3.72, SD = 0.94; those who nearly always display P plates: M = 3.43, SD = 1.09).

Conclusions: The study findings suggest that participants who nearly always display their P plates are more likely to report that having to display their plates resulted in them driving more carefully.  相似文献   

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The EPA recently issued an internal memorandum and a settlement agreement in the case of Chemical Manufacturers Association et al. vs. EPA. The agreement reflects potential changes to the PSD regulations and the Emissions Offset Interpretive Ruling for nonattainment areas. The information presented in this paper is a summary of the significant aspects of the agreement, as it will affect future industrial sources. This paper also discusses other recent changes to the PSD and nonattainment regulations.

The changes to the regulations provide for significant relaxation of some aspects of PSD and the nonattainment regulations. The most significant aspect is the proposed change in the method of tabulating net increases of emissions due to source modifications. The change would allow offset credit for decreases in emissions due to shutdown of equipment based on the potential emission rate rather than the actual.  相似文献   
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In 2002 an incident trend in Air Traffic Management in a European Centre was analysed from a Human Factors perspective, and a single solution was developed, which stopped the incidents occurring. Three years later a new incident trend appeared, which upon analysis appeared to be a more complex version of the former pattern. This required a more comprehensive analysis as well as a more co-ordinated and systemic approach to reduction. In the end, nine recommendations were made, of which more than half were implemented. The incidents stopped. This case study is used to highlight the issue of risk migration in the context of incident analysis and reduction.  相似文献   
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While the new source emission offset provision contained in recent acid rain proposals would result in increasing utility costs over time, the demand for emission offsets from new powerplant units should be satisfied even under conditions of high future growth in electrical generating capacity. This is because the amount of emissions from new generating units will be small relative to the quantity of offsets that could be made available in the emission “allowance” market.

Under the President’s July 1989 proposal, most utilities would be able to reduce their emissions well below their allowance levels via fuel switching, the installation of control technology, or the use of other emission reduction techniques, in order to create more “headroom” for the construction of new generating units. Retirements and decreasing utilization of existing power plants over time would liberate other emission allowances for use by new units. Industrial sources could “opt in” to the acid rain program and provide allowances for new generating units as well. A number of provisions in the recently passed Senate and House bills would make still further sources of allowances available to offset emissions from new generating capacity.

Hoarding of allowances by utilities is unlikely to be a problem since allowances would be distributed to at least 88 utilities in 34 states, and many of these utilities would have the ability to cost-effectively free up more allowances through “overcontrol” than they would need to cover their own future growth. Even a relatively small number of utilities in a limited number of states would have the ability to supply all of the allowances needed to cover new capacity growth from those entities that could not otherwise provide their own offsets. At projected prices of up to $800/ton, the incentives for utilities to sell allowances would be considerable. Moreover, if hoarding did begin to occur, the price of allowances would respond by rising to higher levels and the incentives for utilities to sell allowances would become even more compelling, as greater opportunities would develop for reducing costs (and electricity rates).  相似文献   
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We consider the street experiences of a group of urban children living in a large East Midlands town in the UK. Our attention focuses upon an issue that has seldom been examined, neighbourhood bullying. We highlight how some children, through their propinquity within neighbourhood spaces, clash and collide to such an extent that their experiences of a locality become severely blighted. For these unfortunate young people local environments are tyrannical spaces, defined in terms of 'no-go areas', danger and threat. These are not remarkable geographies, however, and we suggest that like many school environments, where bullying has increasingly been recognised and disclosed, within many localities there is a 'hidden' geography of fear waiting to be uncovered. The paper is organised into five parts: first, we briefly examine the concept of bullying, particularly in relation to young people in schools; secondly, we extend these ideas into a neighbourhood context drawing upon recent ideas of 'self', 'other' and microgeographies; thirdly, we outline the research project from which this article emerges; fourthly, we look at some empirical evidence from an urban case study that draws attention to the form and consequences of neighbourhood bullying; lastly, we discuss the relevance of these findings to future policy and practice, particularly in relation to the management of neighbourhood spaces. We propose that systematically applied local strategies to tackle bullying within neighbourhoods are needed, particularly those which engage young people and adults together through a whole community approach.  相似文献   
308.
Brook BW  Bradshaw CJ 《Ecology》2006,87(6):1445-1451
Population limitation is a fundamental tenet of ecology, but the relative roles of exogenous and endogenous mechanisms remain unquantified for most species. Here we used multi-model inference (MMI), a form of model averaging, based on information theory (Akaike's Information Criterion) to evaluate the relative strength of evidence for density-dependent and density-independent population dynamical models in long-term abundance time series of 1198 species. We also compared the MMI results to more classic methods for detecting density dependence: Neyman-Pearson hypothesis-testing and best-model selection using the Bayesian Information Criterion or cross-validation. Using MMI on our large database, we show that density dependence is a pervasive feature of population dynamics (median MMI support for density dependence = 74.7-92.2%), and that this holds across widely different taxa. The weight of evidence for density dependence varied among species but increased consistently, with the number of generations monitored. Best-model selection methods yielded similar results to MMI (a density-dependent model was favored in 66.2-93.9% of species time series), while the hypothesis-testing methods detected density dependence less frequently (32.6-49.8%). There were no obvious differences in the prevalence of density dependence across major taxonomic groups under any of the statistical methods used. These results underscore the value of using multiple modes of analysis to quantify the relative empirical support for a set of working hypotheses that encompass a range of realistic population dynamical behaviors.  相似文献   
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A study has been conducted over a period of one year on measurements of air pollution in the Shuaiba Industrial Area (SIA) of Kuwait. The study included analysis of pollutant behaviour relative to the wind speed and direction. SIA comprises several large scale industries including three petroleum refineries, two power plants, two fertilizer plants, a cement plant, a chlorine and soda plant, a commercial harbour and two large oil loading terminals. Measurements of 15 parameters have been carried out every 5 minutes using a mobile laboratory fitted with an automatic calibrator and a data storage system. The pollutants studied include methane, non‐methane hydrocarbons (NMHC), carbon monoxide, carbon dioxide, nitrogen oxides (NO, NO2, and NO x ), sulphur dioxide, ozone and suspended dust. Meteorological parameters monitored simultaneously include wind speed and direction, air temperature, relative humidity, solar radiation, and barometric pressure. The air quality data collected using the mobile laboratory have been used to calculate the diurnal and monthly variations in the major primary and secondary pollutants. Distribution levels of these pollutants relative to wind direction and speed have also been used in the analysis. The results show large diurnal variations in some pollutant concentrations. Generally, two types of concentration variations have been found, depending on whether the species is a primary or a secondary pollutant. Diurnal variations with two maxima were observed in the concentrations of primary pollutants including NO, SO2, NMHC, CO and suspended dust, whereas a single maximum was observed for secondary pollutants such as O3and NO2. The monthly variations of SO2and NO x showed maximum values during the warm months. However, ozone showed a quite marked seasonal variation with maxima during spring and late summer and a minimum during the early summer. The results also indicated a common source for NO x , SO2, NMHC, CO and suspended dust to the North‐West (NW) of the monitoring station. Moreover for NO x and SO2, another less significant source is to the South‐South‐West (SSW) and South‐West (SW) of the monitoring station.  相似文献   
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