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291.
Traffic conflict under congested conditions is one of the main safety issues of motorcycle traffic in developing countries. Unlike cars, motorcycles often display non-lane-based movements such as swerving or oblique following of a lead vehicle when traffic becomes congested. Very few studies have quantitatively evaluated the effects of such non-lane-based movements on traffic conflict. Therefore, in this study we aim to develop an integrated model to assess the traffic conflict of motorcycles under congested conditions. The proposed model includes a concept of safety space to describe the non-lane-based movements unique to motorcycles, new features developed for traffic conflict assessment such as parameters of acceleration and deceleration, and the conditions for choosing a lead vehicle. Calibration data were extracted from video clips taken at two road segments in Ho Chi Minh City. A simulation based on the model was developed to verify the dynamic non-lane-based movements of motorcycles. Subsequently, the assessment of traffic conflict was validated by calculating the probability of sudden braking at each time interval according to the change in the density of motorcycle flow. Our findings underscore the fact that higher flow density may lead to conflicts associated with a greater probability of sudden breaking. Three types of motorcycle traffic conflicts were confirmed, and the proportions of each type were calculated and discussed. 相似文献
292.
Within the simulation-based dynamic traffic assignment (SBDTA) model, the time-dependent shortest path (TDSP) algorithm plays a crucial role in the path-set update procedure by solving for the current optimal auxiliary solution (shortest path). Common types of TDSP algorithms require temporal discretization of link/node time/cost data, and the discretization could affect the solution quality of TDSP and of the overall SBDTA as well. This article introduces two variable time-discretization strategies applicable to TDSP algorithms. The strategies are aimed at determining the optimal time discretization for time-dependent links/nodes travel time data. The first proposed strategy produces a specific discretization interval for each link. The second proposed strategy generates time-varying intervals for the same link over the analysis period. The proposed strategies are implemented in a link-based time-dependent A* algorithm in a SBDTA model DynusT and tested with two numerical experiments on two traffic networks. The results show that the proposed discretization methods achieve the research goal—to flexibly and scalably balance the memory usage and run time for SBDTA without degrading the convergence. This property is rather important when dealing with a large real-world network with a long analysis period. 相似文献
293.
Traditionally, traffic monitoring requires data from traffic cameras, loop detectors, or probe vehicles that are usually operated by dedicated employees. In efforts to reduce the capital and operational costs associated with traffic monitoring, departments of transportation have explored the feasibility of using global positioning system (GPS) data loggers on their probe vehicles that are postprocessed for analyzing the traffic patterns on desired routes. Furthermore, most cell phones are equipped with embedded assisted-GPS (AGPS) chips, and if the mode of transportation the phone is in can be anonymously identified, the phones can be treated as if they are probe vehicles that are voluntarily hovering throughout the city, at minimal additional costs. Emerging cell phones known as “smartphones” are equipped with additional sensors including an accelerometer and magnetometer. The accelerometer can directly measure the acceleration values, as opposed to having acceleration values derived from speed values in conventional GPS sensors. The magnetometer can measure mode-specific electromagnetic levels. Smartphones are subscribed with roadside Internet data plans that can provide an essential platform for real-time traffic monitoring. In this article, neural network-based artificial intelligence is used to identify the mode of transportation by detecting the patterns of distinct physical profile of each mode that consists of speed, acceleration, number of satellites in view, and electromagnetic levels. Results show that newly available values in smartphones improve the mode detection rates when compared with using conventional GPS data loggers. When smartphones are in known orientations, they can provide three-dimensional (3-D) acceleration values that can further improve mode detection accuracies. 相似文献
294.
结合生态公路的建设理念及特点,阐述了西南地区建设生态公路的意义,并对公路的景观化及对周边生态的保护提出了相应的看法,希望能够将公路建设与生态保护相融合,保护当地的生物多样性. 相似文献
295.
在大量收集、调研杭瑞高速公路沿线所经“四县一市”的文化景观资源基础上,阐述地域文化的构成要素,景观设计原则,并结合高速公路景观自身的特征,探索地域文化在高速公路上最适宜的景观载体,从而引起人们对于地域文化的传承与保护意识. 相似文献
296.
文章结合行业发展实际,分析了当前交通试验检测机构普遍存在的问题,并从提升试验检测机构检测能力、提高服务水平和从业能力角度提出了相应的解决措施。 相似文献
297.
分析新形势下国内船舶制造企业用工特征、用工行情,结合行业特点,分析船舶制造企业劳动争议现状,以国内典型船舶制造企业的实际经验和数据为基础,总结出新形势下船舶制造企业人力资源管理措施。 相似文献
298.
299.
在城市交通出行环境日益严峻的背景下,公共交通已成为城市发展的关键要素之一,如何提高公共交通的管理质量与效能受到越来越多关注。为解决城市公共交通客流时间不均衡、高峰过度拥挤的问题,提出了时间差别定价的概念。梳理了国内外相关研究进展,从乘客出行时间、边际成本和各方利益三方面分析了时间差别定价在我国的可行性,最后研究了推动时间差别定价实施的策略建议。 相似文献
300.
马英明 《广州航海高等专科学校学报》2014,(1):47-49
子嗣文化是南海神庙文化中一个重要的构成部分。南海神庙文化与子嗣文化的兼容可以说明,广州文化市井味浓,包容性强,让人易于接受易于感动,成为支撑着广州成为国际文化核心城市的强大软实力。 相似文献