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971.
Transportation infrastructure planning process requires cost–benefit analysis in the evaluation of project proposals. Value of time (VOT) facilitates the conversion of travel time savings, which is a significant proportion of benefits in monetary terms. In cases where VOT has not been established, planners resort to crude estimates that often results in erroneous or biased measurements of benefits. This is the case of the Western Visayas region in the Philippines where transportation studies are rare. Secondary cities and its peripheral regions have often been overlooked subjects of transportation studies. In this study, multinomial logit models using revealed preference data were estimated to facilitate the calculation of the VOT. The total cost, square of the total cost, and total time were identified as significant explanatory variables affecting mode choice. The square of the total cost term was introduced in the models in order to account for income effect. Results indicate that VOT estimates for the inter-island passenger transportation between Iloilo and Negros Occidental generally range from 78.15PHP to 179.15PHP (1.91USD to 4.37USD) depending on trip and traveller characteristics. 相似文献
972.
Mahmoud Javanmardi Mehran Fasihozaman Langerudi Ramin Shabanpour Abolfazl Mohammadian 《Transportation》2016,43(6):1023-1039
Activity conflict resolution as the core of scheduling process in activity-based modeling is a challenging step because the activity diary databases mostly report the outcome of the scheduling decisions and often fail to capture key factors influencing the resolution process itself. Consequently, most activity-based frameworks ignore modeling this process by using either predefined set of activity patterns or priority-based assumptions to schedule daily activities and prevent conflict occasions. ADAPTS is one of the few activity-based models that attempts to simulate the process of activity scheduling and resolve the conflicts as they occur. This paper advances the current rule-based conflict resolution model of ADAPTS by implementing an advanced and flexible non-linear optimization model. A set of linear optimization sub-models is then proposed that together perform the same task as the non-linear model, however they are much easier to implement and maintain, while fast to run and flexible to extend. The proposed approach defines an objective function, which aims to minimize the extent of changes in timing and duration of conflicting activities, while fitting them in the schedule. Comparing performance of the proposed model with TASHA scheduler and former resolution module of ADAPTS using CHASE scheduling process data reveals significant improvement in fitting the newly planned activities in the schedules with the minimal modifications in the timing and duration of activities. 相似文献
973.
Existing user equilibrium models of activity-travel scheduling generally fall short in representing travelers’ decision-making processes. The majority have either implicitly or explicitly assumed that travelers follow the principle of utility maximization. This assumption ignores the fact that individuals may be loss–averse when making activity-travel decisions. Allowing for the situation that travelers possess accurate information of the urban-transportation system due to modern technologies, studies on reference-dependent decision-making under near-perfect information are receiving increasing attention. In view of traveler heterogeneity, individuals can be divided into multiple classes according to their reference points. In this paper, we propose a reference-dependent multi-class user equilibrium model for activity-travel scheduling, which can be reformulated as a variational inequality problem. Moreover, comparative analyses are conducted on the equilibrium states between utility-maximization (no reference) and reference-dependency of exogenous and endogenous references. A numerical example regarding combined departure-time and mode choice for commuting is conducted to illustrate the proposed model. The simulated results indicate that reference points and loss aversion attitudes have significant effects on the choice of departure time and mode. 相似文献
974.
In this paper, added resistances acting on a hull of non ballast water ship(NBS) in high waves is discussed. The non ballast water ships were developed at the laboratory of the authors at Osaka Prefecture University, Japan. In the present paper, the performances of three kinds of bow shapes developed for the NBS were theoretically and experimentally investigated to find the best one in high waves. In previous papers, an optimum bow shape for the NBS was developed in calm water and in moderated waves. For a 2 m model for experiments and computations, the wave height is 0.02 m. This means that the wave height is 15% of the draft of the ship in full load conditions. In this paper, added resistances in high waves up to 0.07 m for a 2 m model or 53% of the full load draft are investigated. In such high waves linear wave theories which have been used in the design stage of a ship for a long time may not work well anymore, and experiments are the only effective tool to predict the added resistance in high waves. With the computations for waves, the ship is in a fully captured condition because shorter waves, λ/Lpp0.6, are assumed. 相似文献
975.
蔡昌 《广东交通职业技术学院学报》2014,(2):47-48
针对基于Domino的OA系统当前存在的性能问题进行分析,找出造成性能瓶颈的原因,并提出可行的解决方案来优化性能。 相似文献
976.
常伟 《国防交通工程与技术》2014,(2):69-71
水平泥岩砂岩互层围岩的地质特点导致围岩在施工爆破后易沿结构面及软弱破坏面破坏,形成较难人为控制的超欠挖现象。以大梁峁特长公路隧道为工程背景,提出了相应的超欠挖控制措施:采用科学合理的控制爆破技术和施工措施,经此处理后,超欠挖值明显减小,开挖面基本平整、光滑,隧道施工过程中未发生塌方事故,拱顶掉块也明显减少。 相似文献
977.
使用空气制动系统与纵向动力学联合仿真系统,计算l辆HXD1机车+60辆载重C70车辆+1辆HXD1机车短编组列车加挂350 t落下孔车回送运行施行紧急制动的列车纵向冲动,分析350 t落下孔车编组位置、前后机车操纵同步性对回送列车的纵向动力学影响.仿真分析表明,主控机车和从控机车操作同步性能的好坏直接决定了整列车纵向动力学性能,350 t落下孔长大货物车的位于列车中部时列车最大车钩力增幅最小. 相似文献
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