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151.
李力 《城市道桥与防洪》2020,(1):21-23,36,M0005
农村公路是农村经济发展、人民生活条件改善的重要基础条件,同时其在加强城乡联系、调整农业结构、促进农村土地资源开发等方面发挥了重要作用。但是在农村公路深人发展的同时,其交通安全问题严重影响并制约着农村公路的发展态势。通过研究农村公路线形与交通安全关系,运用交通仿真软件对农村公路线形设计进行了安全性评价,并针对其安全问题提出交通安全保障的主要技术手段。  相似文献   
152.
针对高桩码头的检测评估工作中缺少合理有效的评估方法和评估指标的问题,对结合干扰能量法的高桩码头结构评估指标进行研究。采用变分原理和最小势能原理,结合高桩码头的结构特点,建立基于干扰能量法的高桩码头结构整体安全评价的指标体系,并与现行规范进行对比。结果表明,此方法在评估局部构件的同时,还可定量给出结构的整体安全系数,能够反映不同构件对于整体安全性的贡献。  相似文献   
153.
陈华  高杨 《港工技术》2020,(2):97-100
本文结合某港油库的工业控制系统信息安全升级项目,介绍了该港根据《工业控制系统信息安全防护指南》、《工业控制系统信息安全行动计划(2018-2020)》以及国内外相关标准规范的要求,通过多角度评估,建立健全油库工业控制系统的安全保障体系,实现对其全方位的防护。  相似文献   
154.
王立学  曾海权 《城市道桥与防洪》2019,(2):143-148,M0016,M0017
顶推施工技术作为大跨度钢桁梁施工中非常重要的一项施工技术,其不仅能够有效的缩短工期,而且在不影响既有线路正常运营。依托兰州市北滨河西延段工程大跨度钢桁梁顶推施工项目,从施工方法、措施、技术、安全、质量保证上对顶推施工过程进行全面分析,制定具体施工方案,对顶推过程中钢桁梁的受力特性进行数值计算与分析,以确保施工过程安全可控。通过研究大跨度钢桁梁顶推施工技术与工艺流程要点,优化了施工过程中结构的受力状态,并节约工程造价,可为同类工程建设管理和施工组织提供参考。  相似文献   
155.
One interaction between environmental and safety goals in transport is found within the vehicle fleet where fuel economy and secondary safety performance of individual vehicles impose conflicting requirements on vehicle mass from an individual’s perspective. Fleet characteristics influence the relationship between the environmental and safety outcomes of the fleet; the topic of this paper. Cross-sectional analysis of mass within the British fleet is used to estimate the partial effects of mass on the fuel consumption and secondary safety performance of vehicles. The results confirmed that fuel consumption increases as mass increases and is different for different combinations of fuel and transmission types. Additionally, increasing vehicle mass generally decreases the risk of injury to the driver of a given vehicle in the event of a crash. However, this relationship depends on the characteristics of the vehicle fleet, and in particular, is affected by changes in mass distribution within the fleet. We confirm that there is generally a trade-off in vehicle design between fuel economy and secondary safety performance imposed by mass. Cross-comparison of makes and models by model-specific effects reveal cases where this trade-off exists in other aspects of design. Although it is shown that mass imposes a trade-off in vehicle design between safety and fuel use, this does not necessarily mean that it imposes a trade-off between safety and environmental goals in the vehicle fleet as a whole because the secondary safety performance of a vehicle depends on both its own mass and the mass of the other vehicles with which it collides.  相似文献   
156.
航运枢纽的建设对鱼类生态环境及鱼类资源影响较大,为减缓工程对鱼类的不利影响,文章通过综合分析,提出采取修建过鱼设施和建立增殖保护站、开展人工增殖放流为主要鱼类保护措施,并结合鱼梁枢纽工程,对鱼道结构及布置、增殖保护站布置及生产方式等设计进行介绍。  相似文献   
157.
通过对目前常用驾驶人安全意识培训方法的对比,认为体验式培训为最适合的培训方法;进一步对我国2007-2010年间大型道路交通事故特征进行分析,得出驾乘人员不系安全带是引起人员伤亡一大原因。通过设计研发碰撞、翻转两个体验式训练装置,使驾乘人员在保证安全的前提下真切感受道路交通事故发生瞬间安全带对人体的保护作用,有效提高驾驶人的安全意识,减少道路交通事故的发生及人员的伤亡。  相似文献   
158.
In the fight to reduce CO2 emissions from international shipping, a bunker-levy is currently under consideration at the International Maritime Organization (IMO). Faced with the inability of the IMO to reach an agreement in the short term, the European Commission is now contemplating a unilateral measure of a speed limit for all ships entering European Union (EU) ports. This paper argues that this measure is counterproductive for two reasons. Firstly, because it may ultimately generate more emissions and incur a cost per ton of CO2 which is more than society is willing to pay. Secondly, because it is sub-optimal compared to results obtained if an international bunker-levy was to be implemented. These elements are illustrated using two direct transatlantic services operated in 2010.  相似文献   
159.
This paper develops an operational activity-based method to estimate CO2 emissions from container shipping in contrasts to the traditional aggregated activity-based method. Two case studies investigate the impacts of empty container repositioning policies and port handling capacity on CO2 emission index. The results show that the aggregated method could well overestimate CO2 emissions and the operational activity-based method is more appropriate. The paper also demonstrates that high port-handling capacity and efficient empty container repositioning could reduce CO2 emissions in seaborne container transportation.  相似文献   
160.
Surrogate indicators are meant to be alternatives or complements of safety analyses based on accident records. These indicators are used to study critical traffic events that occur more frequently, making such incidents easier to analyse. This article provides an overview of existing surrogate indicators and specifically focuses on their merit for the analyses of vulnerable road users and the extent to which they have been validated by previous research. Each indicator is evaluated based on its ability to consider the collision risk, which can be further divided into the initial conditions of an event, the magnitude of any evasive action and the injury risk in any traffic event. The results show that various indicators and their combinations can reflect different aspects of any traffic event. However, no existing indicator seems to capture all aspects. Various studies have also focused on the validity of different indicators. However, due to the use of diverse approaches to validation, the large difference in how many locations were investigated and variations in the duration of observation at each location, it is difficult to compare and discuss the validity of the different surrogate safety indicators. Since no current indicator can properly reflect all the important aspects underlined in this article, the authors suggest that the choice of a suitable indicator in future surrogate safety studies should be made with considerations of the context-dependent suitability of the respective indicator.  相似文献   
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