Direct analysis of the perceived importance of attributes of reliability of travel modes in urban travel

Reliability of travel modes was found to be the most important characteristic of transportation systems in several attitudinal investigations of individual travel behavior. This paper represents the first part of a research effort aimed at gaining a better understanding of the characteristics of reliability of transportation modes in urban travel. In this research, reliability characteristics are identified; their importance relative to each other is assessed, and an insight into possible structure of an objective reliability index is discussed. The research is based on perceived values of reliability, which were identified through a large attitudinal survey conducted in the Chicago metropolitan area.     

Transit subsidies and regulation: Lessons from the Israeli experience

The Israeli transport sector, like those of many other countries is subject to complete government control with regard to fares, entry into the market, terms of operation and subsidies. It is unique, however, in that the fares charged are remarkably low and that the major transit mode, buses, is operated by privately owned companies. This paper explores what makes this low level of fares possible and in doing so examines the principal characteristics of the sector. It shows that this phenomenon cannot be explained by the amount of subsidy given to the operators but must be attributed to other factors, mainly the efficiency in the production of the services which is motivated by the profit maximization objective of the operators. The paper further argues that government policies regarding subsidy and regulation are generally inefficient as they cause misallocation of resources.     

Optimisation of active suspension control inputs for improved vehicle handling performance

Active suspension is commonly considered under the framework of vertical vehicle dynamics control aimed at improvements in ride comfort. This paper uses a collocation-type control variable optimisation tool to investigate to which extent the fully active suspension (FAS) application can be broaden to the task of vehicle handling/cornering control. The optimisation approach is firstly applied to solely FAS actuator configurations and three types of double lane-change manoeuvres. The obtained optimisation results are used to gain insights into different control mechanisms that are used by FAS to improve the handling performance in terms of path following error reduction. For the same manoeuvres the FAS performance is compared with the performance of different active steering and active differential actuators. The optimisation study is finally extended to combined FAS and active front- and/or rear-steering configurations to investigate if they can use their complementary control authorities (over the vertical and lateral vehicle dynamics, respectively) to further improve the handling performance.     

Can we really measure the impact of port governance reform?

Approaches by governments to reforming the way in which ports are governed are critical to how ports operate and fulfil their roles, and much research is devoted to investigating the impact of such reform. Yet, although the challenges of such research are noted, little attention is devoted to questioning whether measuring such impact is actually possible. We argue consideration of this question is fundamentally important for policy makers and researchers. Specifically, if uncertainty exists regarding whether we have measured the impact of the reform, how can we research its effect or justify its introduction? Conversely, a more conscious consideration of whether we can really measure the impact of port governance reform arguably means a more effective contextualization and rationalization of both policy and research. In this polemical paper, we critically consider three salient areas in relation to whether we can really measure the impact of port governance reform: ‘key terms and their ambiguity’, ‘aspects of time and geography’ and ‘issues of methods and context’. We summarize the key issues and offer suggestions for policy makers and researchers to approach them in an aim to both help measure the impact of port governance reform and also aid future policy development.     

Network-based real option models

Building on earlier work to incorporate real option methodologies into network modeling, two models are proposed. The first is the network option design problem, which maximizes the expanded net present value of a network investment as a function of network design variables with the option to defer the committed design investment. The problem is shown to be a generalized version of the network design problem and the multi-period network design problem. A heuristic based on radial basis functions is used to solve the problem for continuous link expansion with congestion effects. The second model is a link investment deferral option set, which decomposes the network investment deferral option into individual, interacting link or project investments. This model is a project selection problem under uncertainty, where each link or project can be deferred such that the expanded net present value is maximized. The option is defined in such a way that a lower bound can be solved using an exact method based on multi-option least squares Monte Carlo simulation. Numerical tests are conducted with the classical Sioux Falls network and compared to earlier published results.     

Marine Shoreline Management—A 35-Year Evaluation of Outcomes in San Juan County,Washington, US

In 1976, Washington became the first state to implement the federal Coastal Zone Management Act (CZMA) primarily through the 1971 WA Shoreline Management Act (SMA). However, there has been little effort in Washington to evaluate outcomes of shoreline protection programs post SMA. In 2006–2008, we characterized shoreline conditions in San Juan County over three time periods spanning pre and post SMA and engaged community members to improve effectiveness of shoreline protection. We found modest improvements in forest retention on marine shorelines between pre and post 1977, but few other improvements through time. While we could not measure shoreline construction rates, construction practices for shore armor and overwater structures (docks) have changed very little, despite the increased regulatory standards. The vast majority of shore armor constructed post SMA occurred without mandatory county or state permits likely due to: widespread perception that permits were unnecessary and that permit standards were arbitrary and inconsistently applied; poor understanding of shoreline ecology by community members; lack of county or state enforcement authority and shoreline monitoring programs; and poor permit tracking systems.     

The implications of travel profiles for transportation investment: The Bronx Center Project

Investment in transportation infrastructure is generally regarded as an effective means for inducing economic growth and employment in a region. However, the ability of such investments to achieve these objectives, to a large extent, depends on the degree to which travel results from these investments support or conflict with present travel patterns and needs in this region. Using this view as a basis, this paper analyzes travel conditions and choices in the Bronx New York, where large scale transportation and other development projects (commonly called the Bronx Center Project) are presently taking place. Using a large data base, composed of census tract information on socio-economic and travel behavior, the paper first examines the travel profile of the Bronx population, by estimating travel choice elasticities. On the basis of these elasticities it then assesses the impact of the Bronx Center Project on travel patterns and trends.     

Empirical relation between the typhoon surge deviation and the corresponding typhoon characteristics: a case study in Taiwan

The relation between typhoon surges and typhoon characteristics measured at Kenfang Tidal Station on the northeast coast of Taiwan was studied in this paper. Typhoon characteristics include the typhoon center atmospheric pressure, the typhoon near-center wind speed, the typhoon storm radius, the distance between the typhoon center and the tidal station, and the typhoon approach tracks. The results show that the typhoon surge deviation is strongly dependent on typhoon characteristics. An empirical typhoon surge formula is proposed in terms of the typhoon wind speed, the typhoon storm radius, and the distance between the typhoon center and the tidal station. The coefficients in the empirical formula were evaluated, based on the measured typhoon surge data at Kenfang Tidal Station. The storm surge deviations at Kenfang Station during Typhoons Doug (1994) and Herb (1996) estimated using the proposed empirical formula were compared with the measured data as well as with the results of a numerical study.