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621.
在铁路"一带一路"实践中,各国对系统兼容性、互联互通性要求很高,我国铁路电气化系统制式的特点优势明显,对各种气候条件、速度目标值适应性强。我国地形地貌、气候条件、铁路功能的多样性及各类项目的不断建设,使电气化工程技术人员积累了大量实践经验。通过我国电气化标准与国际标准的理论分析与对比,并结合近10年来海外铁路项目,分析总结铁路电气化工程的实践经验与教训,为"一带一路"国际工程项目提供参考。  相似文献   
622.
本文为对温拌沥青混合料(Warm Mix Asphalt简称WMA)与热拌沥青混合料(Hot Mix Asphalt简称HMA)的主要路用性能进行对比,基于ZQ-WB3型温拌剂在G220牡丹区段的实际施工生产中的应用情况进行了技术分析。结论表明,使用温拌剂可以在不降低沥青混合料性能的情况下达到到温拌温铺的目的,并更具经济性和环保价值。  相似文献   
623.
从北京市违法停车管理遇到的实际问题和适用法律法规上的争议入手,以法理运用和法条理解为基点,通过分析违法停车和临时停车的行为表征,以期为解决北京市违法停车管理提供法制保障。  相似文献   
624.
Negative externalities often surface after policies are implemented. This paper analyses how two “hard” Travel Demand Management (TDM) policies implemented in Singapore to target vehicle ownership and road usage may contribute to a negative externality namely excessive mileage accumulation. This has implications on resource depletion such as petrol wastage, higher CO2 emission and losses in time and productivity. Vehicle ownership in Singapore is managed firstly via the requirement to bid for a Certificate of Entitlement (COE) which entitles the usage of local roads and secondly via the payment of an Additional Registration Fee (ARF) which is refundable between 75% and 50% to incentivise the de-registration of a vehicle before it is 10 years old. Such deregistered vehicles may also be eligible for a COE refund between 0% and 80% depending on age. The COE and ARF costs are significant as they typically account for more than half the purchase price of a vehicle. Furthermore, road usage is subject to Electronic Road Pricing (ERP) fees on busy segments. A sample of over 8700 used cars is analysed to infer the effects of the non-refundable (or “sunk”) and the “variable” portions of the combined cost of COE and ARF as well as the number of ERP gantries on mileage over and above traditional factors such as petrol price and engine size. The findings suggest tweaks to the TDM policies to reduce mileage and its negative implications.  相似文献   
625.
Road networks play a vital role in maintaining a functioning modern society. Many events perceptibly affect the transport supply along these networks, especially natural disasters such as floods, landslides, and earthquakes. Contrary to more common disruptions of traffic from accidents, or maintenance closures, natural disasters are capable of destroying large numbers of roads and usually cover vast areas. When evaluating network damage no single measure alone is able to describe the full extent of network destruction. In this study, we investigated six highly damaging natural disasters, which occurred in the Czech Republic between 1997 and 2010. They were all induced by extreme rainfall or by rapid snowmelt and resulted in floods and landslides. Their impacts are evaluated with respect to the damage to road networks and decreased serviceability. For mutual comparison of the impacts and their analysis we used several criteria, described in the paper, related to economic impacts, physical harm to individuals and infrastructures, and the effects on connectivity and serviceability. We also introduced a new measure based on the network efficiency index which takes into account the importance of nodes based on their population. Moreover, we provide a detailed analysis of one such event in July 1997 that significantly affected the road network of the Zlín region.  相似文献   
626.
ABSTRACT

The safety of maritime transportation along the twenty-first century Maritime Silk Road (MSR) is important to ensure its development and sustainability. Maritime transportation poses risks of accidents that can cause the death or injury of crew members and damage to ships and the environment. This paper proposes a Bayesian network (BN) based risk analysis approach that is newly applied in the main route of the MSR to analyse its relevant maritime accidents. The risk data are manually collected from the reports of the accident that occurred along the MSR. Next, the risk factors are identified and the results from the modelling method can provide useful insights for accident prevention. Historical data collected from accident reports are used to estimate the prior probabilities of the identified risk factors influencing the occurrence of maritime accidents. The results show that the main influencing factors are the type and location of an accident and the type, speed, and age of the involved ship(s). In addition, scenario analysis is conducted to analyse the risks of different ships in various navigational environments. The findings can be used to analyse the probability of each possible maritime accident along MSR and to provide useful insights for shipowners’ accident prevention.  相似文献   
627.
结合丹东地区水毁情况,介绍了路基沉陷、路基坍塌、桥涵破坏、防护与加固工程损坏等4种类型,分析了各类水毁发生的原因,提出防治措施。  相似文献   
628.
李明  邹勃 《北方交通》2007,(1):26-28
通过对沥青混合料掺加聚酯纤维的研究,分析了聚酯纤维增强沥青混合料的马歇尔稳定度、水稳定性、高温稳定性及低温抗裂性,并与基质沥青混合料、SBS改性沥青混合料进行试验对比,指出聚酯纤维对沥青混合料路用性能的影响,为利用纤维加强沥青混合料性能研究提供参考。  相似文献   
629.
论文在对城市道路网形态论述的基础上,以国内牡丹江、常州、扬州、德州四个城市的城市道路网与公交线网的关系为例,对公共交通的线网形态受到城市道路网形态的影响和制约进行了较为详细的论述,最后对道路网布线方法与道路网形态适应性进行了研究,并提出了研究展望,以期对国内公交线路规划起到一定的促进作用。  相似文献   
630.
Road segmentation is one of the most important steps in identification of high accident-proneness segments of a road. Based on the ratio of the Potential to Safety Improvement (PSI) along the road, the objective of the paper is to propose a novel dynamic road segmentation model. According to the fundamental model assumption, the determined segments must have the same pattern of PSI. Experimental results obtained from implementation of the proposed method took four Performance Measures (PMs) into consideration; namely, Crash Frequency, Crash Rate, Equivalent Property Damage Only, and Expected Average Crash Frequency with Empirical Bayes adjustment into the accident data obtained from Highway 37 located between two cities in Iran. Results indicated the low sensitivity of the method to PMs. In comparison with the real high accident-proneness segments, identified High Crash Road Segments (HCRS) obtained from the model, demonstrated the potential of the method to recognize the position and length of high accident-proneness segments accurately. Based on the road repair and maintenance costs limitation index for safety improvement, in an attempt to compare the proposed method of road segmentation with conventional ones, results demonstrated the efficient performance of the proposed method. So as to identify 20 percent HCRS located on a read, the proposed method showed an improvement of 38 and 57 percent in comparison with the best and worst outcomes derived from conventional road segmentation methods.  相似文献   
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