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171.
IntroductionAge- and health-related changes, alongside declines in driving confidence and on-road exposure, have been implicated in crashes involving older drivers. Interventions aimed at improving behind-the-wheel behavior are diverse and their associated impact remains unclear. This systematic review examined evidence on older driver training with respect to (1) road safety knowledge; (2) self-perceived changes in driving abilities; and (3) behind-the-wheel performance. Method Nine databases were searched for English-language articles describing randomized controlled trials (RCTs) and non-RCTs of driver training interventions aimed at those aged 55+ who did not have medical or other impairments that precluded licensure. Quality appraisals were conducted using Cochrane’s Risk of Bias Tool (RoB) and Risk Of Bias In Non-randomized Studies – of Interventions tool (ROBINS – I). [PROSPERO; registration no. CRD42018087366]. Results Twenty-five RCTs and eight non-RCTs met the inclusion criteria. Interventions varied in their design and delivery where classroom-based education, or a combination of classroom-based education with on-road feedback, improved road safety knowledge. Training tailored to individual participants was found to improve self-perceived and behind-the-wheel outcomes, including crashes. Conclusions Interventions comprised of tailored training can improve knowledge of road safety, changes to self-perception of driving abilities, and improved behind-the-wheel performance of older drivers. Future research should compare modes of training delivery for this driver population to determine the optimal combinations of off- and/or on-road training. Practical applications Training programs aimed at older drivers should be supported by theory and research evidence. By conducting comparative trials with a sufficient sample size alongside well-defined outcomes that are designed in accordance with reporting guidelines, the most effective approaches for training older drivers will be identified. 相似文献
172.
173.
随着中厚煤层资源的枯竭,近距离薄煤层群开采成为我国资源的重要补充。煤层群开采时合理的采掘部署是防止工作面瓦斯集中涌出的关键,本文通过分析近距离煤层群开采时各回采顺序下工作面瓦斯涌出量,建立了以工作面瓦斯涌出量预测为基础的近距离煤层群开采优化模型,利用计算机编程实现了模型的可视化操作。该模型通过对比分析全部种回采顺序方案,选择整个回采期间瓦斯涌出量最均衡的方案为最优方案。对翔升煤矿进行了实例分析,结果显示合理的回采方案可以使工作面最大瓦斯涌出量大大减小,使整个回采期间工作面瓦斯涌出量趋于均衡。为煤层群开采优化技术中的瓦斯环节提供了理论依据。 相似文献
174.
Elie Gaget Alison Johnston Diego Pavón-Jordán Aleksi S. Lehikoinen Brett K. Sandercock Alaaeldin Soultan Luka Božič Preben Clausen Koen Devos Cristi Domsa Vitor Encarnação Sándor Faragó Niamh Fitzgerald Teresa Frost Clemence Gaudard Lívia Gosztonyi Fredrik Haas Menno Hornman Tom Langendoen Christina Ieronymidou Leho Luigujõe Włodzimierz Meissner Tibor Mikuska Blas Molina Zuzana Musilová Jean-Yves Paquet Nicky Petkov Danae Portolou Jozef Ridzoň Laimonas Sniauksta Antra Stīpniece Norbert Teufelbauer Johannes Wahl Marco Zenatello Jon E. Brommer 《Conservation biology》2022,36(4):e13877
Protected area networks help species respond to climate warming. However, the contribution of a site's environmental and conservation-relevant characteristics to these responses is not well understood. We investigated how composition of nonbreeding waterbird communities (97 species) in the European Union Natura 2000 (N2K) network (3018 sites) changed in response to increases in temperature over 25 years in 26 European countries. We measured community reshuffling based on abundance time series collected under the International Waterbird Census relative to N2K sites’ conservation targets, funding, designation period, and management plan status. Waterbird community composition in sites explicitly designated to protect them and with management plans changed more quickly in response to climate warming than in other N2K sites. Temporal community changes were not affected by the designation period despite greater exposure to temperature increase inside late-designated N2K sites. Sites funded under the LIFE program had lower climate-driven community changes than sites that did not received LIFE funding. Our findings imply that efficient conservation policy that helps waterbird communities respond to climate warming is associated with sites specifically managed for waterbirds. 相似文献
175.
Quantitative ground-water tracing of conduit-dominated karst aquifers allows for reliable and practical interpretation of karst ground-water flow. Insights into the hydraulic geometry of the karst aquifer may be acquired that otherwise could not be obtained by such conventional methods as potentiometric-surface mapping and aquifer testing. Contamination of karst aquifers requires that a comprehensive tracer budget be performed so that karst conduit hydraulic-flow and geometric parameters be obtained. Acquisition of these parameters is necessary for estimating contaminant fate-and-transport. A FORTRAN computer program for estimating total tracer recovery from tracer-breakthrough curves is proposed as a standard method. Estimated hydraulic-flow parameters include mean residence time, mean flow velocity, longitudinal dispersivity, Peclet number, Reynolds number, and Froude number. Estimated geometric parameters include karst conduit sinuous distance, conduit volume, cross-sectional area, diameter, and hydraulic depth. These parameters may be used to (1) develop structural models of the aquifer, (2) improve aquifer resource management, (3) improve ground-water monitoring systems design, (4) improve aquifer remediation, and (5) assess contaminant fate-and-transport. A companion paper demonstrates the use of these hydraulic-flow and geometric parameters in a surface-water model for estimating contaminant fate-and-transport in a karst conduit. Two ground-water tracing studies demonstrate the utility of this program for reliable estimation of necessary karst conduit hydraulic-flow and geometric parameters. 相似文献
176.
在治理环境污染问题时,经常要从多个污染治理方案中选择最佳的方案,方案选择的合理与否,直接影响到工程的经济性和技术性。以苏南地区常州市老城区主要河道北市河为例,根据该河道的实际情况和环境问题,采用层次分析法对该河道整治工程方案进行了优化选择,以排污口整治、生态修复、污水接管、充氧曝气作为备选方案构建了递阶层次结构模型,在标度选择上采用了指数标度e0/5-e8/5,根据实际需要将北市河分为6个区间段,重点选取了金谷庄园桥到博爱桥区间段,分别进行了判断矩阵构造、层次单排序及其一致性检验、层次总排序及其一致性检验等过程,最终结果取一致性检验均通过的最大权重值方案,其它区间的计算过程与之类似,从而得出了各个区间段的最优化治理方案。 相似文献
177.
Jürgen Bennewitz 《Environment, Development and Sustainability》2009,11(1):127-136
The IPCC Working Groups I–III 2007 publications does not consider the question of the influence of the entropy increase in
the atmosphere on current climate development. An investigation into this question, both in general terms as well as by two
quantitative approaches, reveals we must consider the entropy produced by man in connection with climate development, especially
with regard to the temperature increase of the atmosphere. The IPCC report also fails to mention the production of CO2 by humans and livestock, but calculations show we must also consider such greenhouse gas CO2 production. For solving the mitigating processes, we therefore have to take into account both the human induced entropy production
and the direct human and livestock CO2 output. In consideration of these findings, it seems necessary to introduce an “entropy identity” to people who wish to be
able to continue to live on the planet. The introduction of an entropy tax might also help in solving the most urgent fundamental
problem humanity has ever had to face.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
178.
Scenario study for a regional low-carbon society 总被引:1,自引:0,他引:1
Japan should undertake drastic greenhouse gas (GHG) emission reductions by the middle of this century in order to mitigate
climate change problems. Municipalities should design and execute scenarios toward a low-carbon society suited to their respective
regions. This study describes long-term future visions developed for Shiga Prefecture targeting CO2 emission reductions of 30–50% by 2030, and presents scenarios to attain these targets, which are achievable with mild economic
growth. For targets over a 30% reduction, region-specific measures including land-use reform and citizen behavioral changes
are necessary. Compared with other regions in Japan, Shiga should give priority to a modal shift in transport, efficiency
improvements in industry, and photovoltaic energy generation. 相似文献
179.
147团场自建场以来,在经济发展中取得了巨大成就,但同时必须看到自然对发展的限制与惩罚。从环境学出发,作者对该场的经济与环境发展规划进行了讨论,分析了农业生态环境的有利和不利条件,提出了发展经济与合理利用环境资源的建议。 相似文献
180.