Planning and Evaluation of Passenger Ferry Service in Hong Kong

A predominant observation in Hong Kong is the continuous loss in ferry patronage. There are two main reasons for this: poor level-of-service and better competitors. New roads, bridges, and tunnels are serving the buses, and to some extent the railways; whereas the investment in ferry terminals is relatively at a lower level. On the one hand, there is no need to promote the ferries in a free market environment; but on the other hand, the ferries have the best safety record, can only relieve some traffic congestion and need water access that is one of the characteristics of Hong Kong. The goal of this paper is to design a planning approach combined with an evaluation procedure on how to make the best use of the existing water and pier resources in Hong Kong through the provision of commercially viable ferry services. The approach used covers the impact of future developments planning up to 2006 comprising all public transport modes in Hong Kong (heavy rail, metro, bus, and ferry). The planning tool is based on a newly developed multi-objective evaluation method in order to assess the ferry routes with scientific, practical, and simplified analyses for future use. This assessment is applied to the existing ferry routes and candidate routes and can also be carried out on an individual route basis or on a given set of routes. The objective functions set forth analytically in the evaluation method take into account the interests of the three participants: the passengers, the operators and the government. The proposed ferry network design formulation and the suggested new ferry routes will have a positive impact on changing the ferry system’s image in Hong Kong.     

Analysing Demand for Suburban Trips: A Mixed RP/SP Model with Latent Variables and Interaction Effects

We analyse mode choice behaviour for suburban trips in the Grand Canary island using mixed revealed preference (RP)/stated preference (SP) information. The SP choice experiment allowed for interactions among the main policy variables: travel cost, travel time and frequency, and also to test the influence of latent variables such as comfort. It also led to discuss additional requirements on the size and sign of the estimated model parameters, to assess model quality when interactions are present. The RP survey produced data on actual trip behaviour and was used to adapt the SP choice experiment. During the specification searches we detected the presence of income effect and were able to derive willingness-to-pay measures, such as the subjective value of time, which varied among individuals. We also studied the systematic heterogeneity in individual tastes through the specification of models allowing for interactions between level-of-service and socio-economic variables. We concluded examining the sensitivity of travellers’ behaviour to various policy scenarios. In particular, it seems that contrary to political opinion, in a crowded island policies penalising the use of the private car seem to have a far greater impact in terms of bus patronage than policies implying direct improvements to the public transport service.     

The Impact of Travel Time Information on Travelers’ Learning under Uncertainty

In this work, laboratory experiment was conducted in order to evaluate the effect of feedback on decision-making under uncertainty, with and without provided information about travel times. We discuss the prediction of travelers’ response to uncertainty in two route–choice situations. In the first situation travelers are faced with a route–choice problem in which travel times are uncertain but some external information about routes’ travel times is provided. The second situation takes place in a more uncertain environment in which external information about travel times is not provided, and the travelers’ only source of information is their own experience. Experimental results are in conflict with the paradigm about traveler information systems: As a consequence of information, the propensity of travelers to minimize expected travel time is not necessarily increased. Providing travelers with static information about expected travel times reveals an increase in the heterogeneity of travelers’ choices and reduces the maximization rate.     

Mixed Logit模型及其在交通方式分担中的应用研究

离散选择模型的典型代表Logit模型简洁易用的特点使其在经济、交通等领域得到了广泛的应用，但同时Logit模型的两个重要缺陷限制了其应用范围。在分析了Logit模型固有的两个缺陷和Mixed Logit模型的良好性质后，比较了Logit模型与Mixed Logit模型的差异，对Mixed Logit模型的算法进行了研究，并借助SAS统计软件提供的仿真算法给出了详细的工程实践应用范例。结果表明，Mixed Logit模型有着更丰富的物理含义，对个人出行交通方式选择行为的描述更符合实际。     

信号控制对动态路线选择的影响研究

以动态路线选择模型为基础的先进的出行者信息系统（ＡＴＩＳ）的实施必然对城市交通控制系统产生影响，同时交通控制系统的控制方案对路线诱导信息“运行时间”的估计也发生作用，影响用户对最优路线的造选择。对两系统的相互关系进行了分析，并建立了两系统相互关系模型最后给出了实际案例分析。     

基于期望间距的车辆跟驰模型的建立

以“期望间距”为基准参理，考虑驾驶员的心理和生理因素，建立了车辆跟驰模型，为研究驾驶行为提供了一种新的思路。     

A conceptual and methdological framework for the generation of activity-travel patterns

This paper develops a conceptual framework for the generation of activity and travel patterns in the context of more general structures and presents an integrated model system as a step toward development of an improved travel demand forecasting model system. We propose a two-stage structure to model activity and travel behavior. The first stage, the stop generation and stop/auto allocation models, consists of the choices for the number of household maintenance stops and the allocation of stops and autos to household members. The second stage, the tour formation model, includes the choices for the number of tours and the assignment of stops to tours for each individual, conditional on the choices in the first stage. Empirical results demonstrate that individual and household socio-demographics are important factors affecting the first stage choices, the generation of maintenance stops and the allocation of stops and autos among household members, and the second stage choices, the number of tours and the assignment of stops to tours. This revised version was published online in June 2006 with corrections to the Cover Date.     

砂卵石地层台阶法施工隧道围岩-支护结构应力应变特性三维离散元分析

为了解砂卵石地层隧道围岩和支护结构的应力应变特性，以青海循隆高速公伯峡隧道为依托，借助PFC3D离散元软件对公伯峡隧道穿越砂卵石地层进行三维模拟，重点研究以密排短管棚预支护为根本前提，以三台阶预留核心土为施工方法的砂卵石地层围岩和支护结构的应力应变特性，并与现场实测进行对比分析。研究结果表明： 隧道台阶开挖时，围岩应力集中范围逐渐从拱顶过渡到拱腰，直到拱脚，对应的塑性区范围不断扩大，且密排短管棚对塑性区的发展有一定的“遮拦效应”； 围岩横纵向变形规律一致，主要是向隧道临空面产生收敛变形，且密排短管棚形成的梁拱效应限制了掌子面前方位移发展； 2种方法得到的初期支护变形规律一致，均呈阶段性变化，拱顶下沉累计值大于周边收敛累计值，且两者的最终变形量均满足规范限值要求。     

最小二乘平差在纸海图矢量化过程中的应用

在矢量化纸海图时,由于基准点的采样误差,导致转换参数的误差,最终导致电子海图的空间对象的精度不高。本文应用最小二乘法对基准点的采样误差实施平差,提高转换参数的精度,最终可较大幅度地提高电子海图中空间对象的精度