This study proposes a methodology to solve the integrated problems of selection and scheduling of the exclusive bus lane. The selection problem intends to determine which roads (links) should have a lane reserved for buses while the scheduling problem intends to find the time period of the application. It is formulated as a bi-objective optimization model that aims to minimize the total travel time of non-bus traffic and buses simultaneously. The proposed model formulation is solved by the hybrid non-dominated sorting genetic algorithm with Paramics. The results show that the proposed methodology is workable. Sets of Pareto solutions are obtained indicating that a trade-off between buses and non-bus traffic for the improvement of the bus transit system is necessary when the exclusive bus lane is applied. This allows the engineer to choose the best solutions that could balance the performance of both modes in a multimode transport system environment to achieve a sustainable transport system.

This paper investigates the quantitative characteristics of the vehicle arrival pattern on highways. Inspired from a remarkable finding on data network traffic that most data packet arrival patterns follow the self-similar process as opposed to the classical Poisson process, this paper aims to explore whether the vehicle arrival pattern on highways exhibit the self-similarity property and the corresponding time headway distribution it obeys. By using real highway traffic data provided by the Texas Department of Transportation, United States, this paper examines the existence of self-similarity characteristics on these vehicle arrival data. This is done by estimating the Hurst parameter, which is an index for self-similarity testing. Hypothesis testing for the Hurst parameter estimation shows that the highway vehicle arrival pattern under moderate to heavy traffic conditions exhibit the self-similarity behavior. Then, using the headway data recorded from the Federal Highway situated in Kuala Lumpur of Malaysia, this paper further demonstrates that the time headway of vehicles on the highways follows the heavy-tailed distribution rather than the classical exponential distribution. These two novel findings not only shed some light on the existence of a new distribution to describe the vehicle arrival pattern but also enrich the studies on traffic flow theory.

Globally, the environmental sustainability of air transport is receiving greater concern nowadays owing to its critical impact on climate change. This paper provides an overview of the environmental (green) issues in relation to aviation activities, focusing on aircraft emission and noise. The influential factors of the respective green issue (including aircraft characteristics and operations) as well as the relevant mitigation strategies, ranges from the technological innovation, operational strategy, fleet planning to the policies, rules and regulations are discussed accordingly. Besides, mathematical modeling, statistical analysis and survey which emerge to be the main methodologies adopted to alleviate the green issues are also discussed in detailed. Concisely, the literatures reveal that there is no single strategy or approach that can be implemented to ease the green issue. Thus, integrated effort and commitment from the relevant parties are required to yield a greener system. By identifying the literature gaps and also the potential rooms for improvement under uncertainty, it is anticipated that this paper could provide some useful insights to the relevant parties in charting the effective strategies to attain a green air transport system.

Malaysia is one of the few countries in the world that provides a fuel subsidy to consumers. Due to the recent economic crisis, the Malaysian Government decided to revise its fuel subsidization policy from a fixed price subsidy to a floating price subsidy dependent on global oil demand. Recognizing that the change in fuel subsidization policy can have an impact on travel behavior, this article investigates the short-term impact of the policy change on private and public transportation in the Klang Valley region of Malaysia. Spectral analyses are performed to investigate if the policy change has an impact on private vehicle travel demand, measured in terms of road traffic, and short-term travel demand elasticity with respect to fuel price is estimated. To measure the impact on the public transportation system, the demand cross-elasticity values of rail transit and buses are also estimated. It was found that traffic flow reduces with an increase in fuel price, although elasticity and cross-elasticity values obtained are low. The article finds that there is a potential mode shift from private vehicles to rail transit with increasing fuel price. It is demonstrated that reducing fuel price subsidy can be an effective travel demand management strategy to alleviate congestion.

Megacities worldwide have been employing some form of traffic information systems to manage their road network and to mitigate congestion. However, the full benefits of such systems can only be achieved if drivers perceive the system to be of adequate quality for them to actually use the disseminated information in their travel choices. One way to evaluate the underlying quality of the system is to conduct questionnaire survey, gather direct driver feedback and perform statistical analyses to derive attributes or indicators such as driver awareness, utilization of traffic information and perceived effectiveness which are useful to agencies for their planning and management activities. However many past works have treated the attributes to be independent and did not offer a complete picture on the perceived quality of the traffic information system. This paper therefore presents the development of a holistic structural equation model that can consider all potential attributes affecting perceived quality in a single framework. Attributes considered in the paper include: driver awareness, driver utilization, perceived effectiveness, expectation, and perceived necessity of the system. Using the traffic information system in Klang Valley, Malaysia as a case study, it is demonstrated that there are causal and cross-loading relationships between the attributes contributing to perceived system quality and the attributes must be considered in a comprehensive manner. In addition, the model offers a useful interpretation on the factors affecting road user perception on the traffic information system, thereby allowing agencies to undertake appropriate measures to further improve the level of user satisfaction.