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371.
The goal of a network design problem (NDP) is to make optimal decisions to achieve a certain objective such as minimizing total travel time or maximizing tolls collected in the network. A critical component to NDP is how travelers make their route choices. Researchers in transportation have adopted human decision theories to describe more accurate route choice behaviors. In this paper, we review the NDP with various route choice models: the random utility model (RUM), random regret-minimization (RRM) model, bounded rationality (BR), cumulative prospect theory (CPT), the fuzzy logic model (FLM) and dynamic learning models. Moreover, we identify challenges in applying behavioral route choice models to NDP and opportunities for future research. 相似文献
372.
Knowledge on human behaviour in emergency is crucial to increase the safety of buildings and transportation systems. Decision making during evacuations implies different choices, of which one of the most important concerns is the escape route. The choice of a route may involve local decisions on alternative exits from an enclosed environment. This study investigates the effect of environmental (presence of smoke, emergency lighting and distance of exit) and social factors (interaction with evacuees close to the exits and with those near the decision-maker) on local exit choice. This goal is pursued using an online stated preference survey carried out making use of non-immersive virtual reality. A sample of 1503 participants is obtained and a mixed logit model is calibrated using these data. The model shows that the presence of smoke, emergency lighting, distance of exit, number of evacuees near the exits and the decision-maker and flow of evacuees through the exits significantly affect local exit choice. Moreover, the model indicates that decision making is affected by a high degree of behavioural uncertainty. Our findings support the improvement of evacuation models and the accuracy of their results, which can assist in designing and managing building and transportation systems. The main aim of this study is to enrich the understanding of how local exit choices are made and how behavioural uncertainty affects these choices. 相似文献
373.
陈红 《武汉船舶职业技术学院学报》2009,8(3):114-116
本文简要介绍了听力理解的实质和图式理论,探讨了图式理论在英语听力教学中的应用。指出教师要在教学中充实、激活和应用相关图式,以提高学生的听力能力。 相似文献
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"聚焦物流"是美军提出的一种先进物流理念,它要求在准确的地点、时间提供给联合作战各种参战人员和各类装备数量合适的后勤物资供应,它建立在以网络为基础的实时可视化信息系统之上,高效快速地连接战场指挥官和后勤供应机构,通过物流机构和程序的改革,为联合作战提供多功能的后勤保障。"聚焦物流"在历次局部战争中得到很好应用,取得良好... 相似文献
376.
为详细研究降雨量对OD行程时间可靠性的影响,基于Uber 出行共享的3 年美国波士顿10 对OD行程时间数据及WeatherUnderground 网站提供的小时历史天气,构建了OD行程时间高斯混合模型(GMM). 模型参数利用EM法进行求解,K 值根据K-S 检验后的P 值 (大于0.500 0)进行确定,模型分位数利用二分法进行求解. 提出一种基于缓冲指数(BI)的新指标——缓冲指数变化率(BIVR)作为定量评估指标. 结果表明:降雨会降低总体OD行程时间可靠性,降低效果随降雨量提高而增强,但增强效果并不明显;尽管可能性较低,但当降雨处于次要影响因素时可能提高可靠性;小雨天气可视为正常天气;雨天可靠性显著低于正常天气,居民在雨天(除小雨外)出行应预留更多时间. 相似文献
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高速公路收费经营企业的发展战略是基于高速公路的基本特征及其未来发展趋势的前提下制定的,因此,理解高速公路的产业特征是制定高速经营发展战略的前提,同时企业战略思想的把握决定着高速公路企业经营发展战略的制定方向。 相似文献
380.
With the progress of information and sensing technologies, estimating vehicular queue length at signalized intersections becomes feasible and has attracted considerable attention. The existing studies provided a solid theoretical foundation for the estimation; however, the studies have some restrictions or limitations more or less. This paper presents a new methodology for estimating vehicular queue length at signalized intersections using multi-source detection data under both undersaturated and oversaturated conditions. The methodology applies the shockwave theory to model queue dynamics. Using data from probe vehicles and point detectors, analytical formulations for calculating the maximum and minimum (residual) queue lengths of each cycle are developed. Ground truth data were collected from numerical experiments conducted at two intersections in Shanghai, China, to verify the proposed methodology. It is found that the methodology has mean absolute percentage errors of 17.09% and 12.28%, respectively, for maximum queue length estimation in two tests, which are reasonably effective. However, the methodology is unsatisfactory in estimating the residual queue length. Other limitations of the proposed models and algorithms are also discussed in the paper. 相似文献