For incident response operations to be appreciated by the general public, it is essential that responsible highway agencies are capable of providing the estimated clearance duration of a detected incident at a level sufficiently reliable for motorists to make proper decisions such as selecting a detour route. Depending on the estimated clearance duration, the incident response center can then implement proper strategies to interact with motorists, ranging from providing incident information only to executing mandatory detouring operations. This study presents a knowledge-based system, based on detailed incident reports collected by the Maryland-CHART (Coordinated Highway Action Response Team) program between years 2012 and 2016, for such needs. The proposed system features the use of interval-based estimates derived from knowledge of historical data, with different confidence levels for each estimated incident clearance duration, and its rule-based structure for convenient updates with new data and available expertise from field operators. As some key variables associated with incident duration often only become available as the clearance operations progress, the developed system with its sequential nature allows users to dynamically revise the estimated duration when additional data have been reported. The preliminary evaluation results have shown the promise of the developed system which, with its invaluable historical information, can circumvent the many data quality and availability issues which have long plagued the applicability of some state-of-the-art models on this subject.

Autonomous driving technology, in which cars recognise their surroundings and drive by way of mechanical control, has attracted much attention. However, before the introduction of autonomous driving technology, there will be a mixture of autonomous and non-autonomous vehicles, which will require a traffic operation management strategy to ensure the safety and operational efficiency of the mixed traffic flow. In response, an operation plan is proposed here to design and operate a managed lane to minimise friction between autonomous and non-autonomous vehicles in the commercialisation phase of autonomous vehicles (AVs). To evaluate this AV managed-lane operation strategy, effectiveness measurements relation to safety, operation efficiency and the environment were derived by conducting a simulation analysis using Vissim software. Then, a value function was developed that reflects the three measurements and their importance weighting values. Using this approach, the paper provides a strategy of optimal AV managed-lane operation that can increase operational efficiency and safety in expressway on/off-ramp areas.

Traditionally, traffic safety improvement programs (TSIPs) have been based on the number of crashes at a specific location or their severity. However, the crash datasets used for such programs are obtained from the police and include two limitations: not all crashes are collected by the police (most minor and near-miss crashes are not reported), and the traditional process uses crash data recorded for the past two or three years (meaning most data inevitably include a time lag). To overcome these limitations, this study proposes a new approach for a TSIP based on citizen participation through an online survey that is broadcasted through social media. The method uses the public as sensors of hazardous road information, which means that information can be collected on individual experiences of minor crashes and latent risk factors, such as near misses and traffic conflicts. To demonstrate this approach, a case study was carried out in a small district in the city of Goyang, Korea, which has one of the highest usage rates of social media technologies. The proposed method and a traditional method were both assessed.