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71.
针对南京市典型道路的交通噪声控制措施,分别选取低噪声路面、声屏障、隔声窗3种噪声控制措施进行监测,监测显示低噪声路面对整体声级降噪有限,声屏障对于1kHz倍频带以上的中高频隔声相对较好,真空玻璃隔声窗能对低频噪声有显著改善。 相似文献
72.
分析云南山区公路严峻的交通形势,及山区公路交通事故的特征、事故形态及影响因素,研究山区公路交通事故发生的机理。从人、车、路和环境等方面分析事故产生的原因,提出针对云南山区事故多发路段安全对策措施。分析表明,在云南山区,路况、人员安全素质、车辆性能、安全管理均处于较低水平,是重大事故多发的根本原因。提高系统安全性,实现系统功能最强,应使系统各要素相互匹配,以实现本质安全。 相似文献
73.
A. V. KOCIOLEK A. P. CLEVENGER C. C. ST. CLAIR D. S. PROPPE 《Conservation biology》2011,25(2):241-249
Abstract: One potential contributor to the worldwide decline of bird populations is the increasing prevalence of roads, which have several negative effects on birds and other vertebrates. We synthesized the results of studies and reviews that explore the effects of roads on birds with an emphasis on paved roads. The well‐known direct effects of roads on birds include habitat loss and fragmentation, vehicle‐caused mortality, pollution, and poisoning. Nevertheless, indirect effects may exert a greater influence on bird populations. These effects include noise, artificial light, barriers to movement, and edges associated with roads. Moreover, indirect and direct effects may act synergistically to cause decreases in population density and species richness. Of the many effects of roads, it appears that road mortality and traffic noise may have the most substantial effects on birds relative to other effects and taxonomic groups. Potential measures for mitigating the detrimental effects of roads include noise‐reduction strategies and changes to roadway lighting and vegetation and traffic flow. Road networks and traffic volumes are projected to increase in many countries around the world. Increasing habitat loss and fragmentation and predicted species distribution shifts due to climate change are likely to compound the overall effects of roads on birds. 相似文献
74.
丁芝华 《中国安全科学学报》2010,20(8)
介绍和分析现代道路交通安全治理的3种思想。应用其中非常值得我国借鉴的系统治理思想对现行道路交通安全立法进行分析。现行道路交通安全立法仅围绕驾驶人的行为控制而设计,围绕道路交通安全管理部门的职能而展开,在很大程度上局限于道路交通秩序管理,在体系上存在缺失,影响道路交通安全治理的工作及其成效。基于当前形势分析,我国有必要也有条件借鉴道路交通安全系统治理的先进思想,重新构建道路交通安全立法的体系。该体系的重构需从道路安全保障、车辆安全保障、交通秩序管理、运输安全运营、交通事故处理等5个方面展开。 相似文献
75.
张新海 《中国安全科学学报》2009,19(6)
针对传统交通事故动态分析法在交通肇事逃逸案件侦查中投入高、效率低、精度差的缺点,笔者在信息主导警务理念的指导下,综合运用逻辑学、系统科学、社会学、心理学、情报科学相关原理,动态分析交通事故现场的痕迹、车辆行驶轨迹、道路交通环境、警情综合信息、驾驶人行为与逃逸心理,以及受害者损伤特征,准确掌握车辆或驾驶人局部特征,从而为侦破交通肇事逃逸案件提供精确的查缉信息,使警务行动实现精确用警、快速反应和精确打击的目标。笔者给出了利用动态分析法侦破交通肇事逃逸案件的流程和步骤;指出提高办案水平,迫切需要加强警务信息和社会信息的有效融合,研发专门系统,强化信息研判。 相似文献
76.
徐毅刚 《中国安全科学学报》1995,(Z2)
我国的道路交通事故是严重的。在对我国道路交通事故特点进行比较研究的基础上,分析了道路交通事故多发的原因,提出了提高道路交通系统安全性的建议。 相似文献
77.
Climatic and stream-flow controls on tree growth in a Western montane riparian forest 总被引:2,自引:0,他引:2
Humans have severely impacted riparian ecosystems through water diversions, impoundments, and consumptive uses. Effective
management of these important areas is becoming an increasingly high priority of land managers, particularly as municipal,
industrial, and recreational demands for water increase. We examined radial tree growth of four riparian tree species (Pinus jeffreyi, Populus trichocarpa, Betula occidentalis, and Pinus monophylla) along Bishop Creek, California, and developed models relating basal area increment (BAI) and relative basal area increment
(RBAI) to climatic and stream flow variables. Between years 1995–1999, univariate regression analysis with stream flow explained
29 to 61% of the variation in BAI and RBAI among all species except P. trichocarpa; growth by P. trichocarpa was not significantly related to stream flows over this period. Stepwise linear regression indicated that species responded
differently to climatic variables, and models based on these variables explained between 33 to 86% of variation in BAI and
RBAI during the decade of the 1990s. We examined branch growth of P. trichocarpa for sensitivity to differences in stream flow regimes and found that annual branch growth did not vary between a high- and
low-flow site, but that annual branch growth was significantly higher in wet years with greater stream flows. Our results
support the establishment of site-specific management goals by land managers that take into account all of the important tree
species present in riparian ecosystems and their differential responses to altered hydrologic condition. Instream flow requirements
for maintaining tree growth and vigor are only one of the species-specific responses that need to be evaluated, and these
assessments should attempt to separate experimentally stream-flow (managed) controls from climatic (unmanaged) controls on
growth. 相似文献
78.
基于多Agent技术的交通事故救援系统的研究 总被引:6,自引:0,他引:6
着重介绍了目前人工智能领域的研究热点问题———Agent技术的概念与原理 ,以及多Agent组的概念和分类 ;提出了基于多Agent技术的交通事故救援系统的流程框架 ;论述了该系统每一个Agent成员所能够完成的主要功能 ;通过该系统的实现 ,可以提高交通事故的及时报警与快速解决的效率 ,实行更加有效的交通流量合理分配 ;在利用既有交通基础设施的基础上增强了出行者的出行便利。笔者认为 ,随着Agent技术和网络技术研究的不断深入 ,基于Agent的应用研究必将有着更广泛的应用前景 相似文献
79.
George A. Whetstone 《Journal of the American Water Resources Association》1972,8(3):600-607
ABSTRACT The Republic of South Africa, legatee of a three-century history of recurring drought, is firmly committed to a program of the optimum use of its water for the national benefit. Its water law encourages centralized planning in that water is held to be the property of the state and is assignable without requiring acquiescence by the basin or province of origin. Interbasin diversions from the Tugela River to the Vaal River Basin, from the Orange River to the Fish and Sundays River Basins, and from several basins to Cape Town are under construction as are facilities for water importation from Lesotho and Angola. For satisfaction of demands beyond the year 2000 the nation may depend increasingly on a shift of its power production and water-using industry from the coal fields of the central plateau to nuclear power development with associated desalination along its coasts. Alternatively, and preferably, it may cooperate in a co-prosperity bloc in Southern Africa aiding the economies of its neighbors by development for mutual advantage of the water and power resources of the Okavango and other northern rivers. 相似文献
80.
BACKGROUND: The use of safety belts is the single most effective means of reducing fatal and nonfatal injuries in motor-vehicle crashes. This paper summarizes the systematic reviews of two interventions to increase safety belt use: primary enforcement safety belt laws and enhanced enforcement of safety belt laws. The reviews were previously published in the American Journal of Preventive Medicine. METHODS: We conducted the systematic reviews using the methodology developed for the Guide to Community Preventive Services. RESULTS: These reviews provide strong evidence that primary laws are more effective than secondary laws in increasing safety belt use and decreasing fatalities and that enhanced enforcement is effective in increasing safety belt use. Increases in belt use are generally highest in states with low baseline rates of belt use. DISCUSSION: Primary safety belt laws and enhanced enforcement programs tend to result in greater increases in usage rates for target groups with lower baseline rates. Concerns regarding public opposition to these interventions may impede their implementation in some jurisdictions. However, surveys indicate that a substantial majority of the public supports implementation of both primary laws and enhanced enforcement programs. CONCLUSION: Based on the strong evidence for effectiveness of primary safety belt laws and enhanced enforcement programs, the Task Force on Community Preventive Services recommended that all states enact primary safety belt laws and that communities implement enhanced enforcement programs. 相似文献