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991.
ProblemAutomobile crashes remain a prominent cause of death and injury for teenagers in the United States. While it is generally agreed that graduated drivers licensing (GDL) influences crash rates, it is unclear which components have the strongest effect on any specific types of crashes.MethodWe analyze the relative effect of different stages of GDL on teenage fatal and injury crash risk via a negative binomial generalized linear model with random state effects. Overall, nighttime, and crashes with multiple teenage passengers are considered.ResultsThe strongest effects are seen by 16-year-olds, for which a strict permit stage is associated with a 58% reduction in fatal crash risk over a lenient permit stage. Similar reductions are seen for injury crashes. The intermediate stage, involving nighttime and passenger restrictions, is associated with a 44% reduction in fatalities but has relatively little effect on injury crashes. The strongest effects are generally seen for passenger crashes, followed by nighttime, and then overall crashes.Impact on IndustryThis study identifies stronger relationships between GDL and crash risk than has previously been discovered and captures the relative effects of permit and intermediate licensing restrictions, two high-level components of GDL which differ in intent and implementation. 相似文献
992.
Xiong Qinli Xiao Yang Halmy Marwa Waseem A. Pan Kaiwen Dakhil Mohammed A. Zhang Lin Li Ting Liang Pinghan 《Environmental science and pollution research international》2020,27(7):7040-7052
Environmental Science and Pollution Research - Land use/land cover (LULC) changes impact the structure and functioning of ecosystems, which consequently influences the provisioning of a range of... 相似文献
993.
Environmental Fluid Mechanics - Relative permeability and resistivity index are important parameters in petrophysics experiments and reservoir evaluations. According to the results of previous... 相似文献
994.
Jinzhi Wang Zhengyi Hu Xingkai Xu Xia Jiang Binghui Zheng Xiaoning Liu Xubin Pan Paul Kardol 《Waste management (New York, N.Y.)》2014,34(8):1546-1552
Combined pre-composting and vermicomposting has shown potential for reclamation of solid wastes, which is a significant source of ammonia (NH3), and greenhouse gases (GHG), including nitrous oxide (N2O), methane (CH4), and carbon dioxide (CO2). Earthworms and amendments may both affect physico-chemical characteristics that control gas-producing processes, and thus affect NH3 and GHG emissions. Here, we used two-way ANOVA to test the effects of addition of reed straw and combined addition of reed straw and zeolite on NH3 and GHG emissions during pre-composting of duck manure, either with or without a follow-up phase of vermicomposting. Results showed that cumulative N2O, CH4, and CO2 emissions during pre-composting and vermicomposting ranged from 92.8, 5.8, and 260.6 mg kg?1 DM to 274.2, 30.4, and 314.0 mg kg?1 DM, respectively. Earthworms and amendments significantly decreased N2O and CH4 emissions. Emission of CO2 was not affected by earthworms, but increased in responses to addition of reed straw. Cumulative NH3 emission ranged from 3.0 to 8.1 g kg?1 DM, and was significantly decreased by reed straw and zeolite addition. In conclusion, combined pre-composting and vermicomposting with reed straw and zeolite addition would be strongly recommended in mitigating emissions of N2O, CH4, and NH3 from duck manure. Moreover, this method also provides nutrient-rich products that can be used as a fertilizer. 相似文献
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996.
997.
A GIS-based decision support system for regional eco-security assessment and its application on the Tibetan Plateau 总被引:1,自引:0,他引:1
Regional eco-security assessment is an intricate, challenging task. In previous studies, the integration of eco-environmental models and geographical information systems (GIS) usually takes two approaches: loose coupling and tight coupling. However, the present study used a full coupling approach to develop a GIS-based regional eco-security assessment decision support system (ESDSS). This was achieved by merging the pressure-state-response (PSR) model and the analytic hierarchy process (AHP) into ArcGIS 9 as a dynamic link library (DLL) using ArcObjects in ArcGIS and Visual Basic for Applications. Such an approach makes it easy to capitalize on the GIS visualization and spatial analysis functions, thereby significantly supporting the dynamic estimation of regional eco-security. A case study is presented for the Tibetan Plateau, known as the world’s “third pole” after the Arctic and Antarctic. Results verified the usefulness and feasibility of the developed method. As a useful tool, the ESDSS can also help local managers to make scientifically-based and effective decisions about Tibetan eco-environmental protection and land use. 相似文献
998.
999.
Collecting municipal solid waste (MSW) is a major and expensive task for local waste management authorities, thus efficient MSW collection is a necessity. This study presents a procedure for developing an aggregate indicator (AI) to assess MSW collection efficiency based on multiple factors. The applicabilities of various key performance indicators (KPIs) are evaluated based on five selection criteria, and five KPIs are chosen to form the AI. The relative efficiencies of local MSW collection services are analyzed by the data envelopment analysis (DEA) method. A set of common weights for all five KPIs is then generated based on DEA results and four selection rules by modifying a previous approach. Finally, the proposed AI is applied to assess the MSW collection services provided by 307 local governments in Taiwan, and associated results are compared and discussed. 相似文献
1000.
Jenq-Renn Chen Hsiao-Yun TsaiJui-Hsing Chien Huang-Jen Pan 《Journal of Loss Prevention in the Process Industries》2011,24(5):662-670
In this study, direct visualization of flow and flame from the ignition of methane/air and propane/air mixtures near the UFL at elevated pressures of up to 2.0 MPa were obtained with a test cell comprised of double-sided plexiglass and a containment vessel with double-sided glass. These visualizations allowed direct observations of ignition and flame near UFL at elevated pressures. Two distinctive features were observed in ignition at elevated pressures that differ from those under ambient pressure: the hot igniter formed a convective plume, rather than a convection cell; and the flame initiated from the top of the test cell and propagated downwards, rather than directly from the igniter. Both these distinctive features are characteristics of convection at high Rayleigh number accompanied with increased gas density at elevated pressures. Our study also shows that visualization of the formation of planar flame provides the most objective criterion for defining flammability limits at elevated pressures. 相似文献