No abstract

The unprecedented COVID-19 outbreak has significantly influenced our daily life, and COVID-19’s spread is inevitably associated with human mobility. Given the pandemic’s severity and extent of spread, a timely and comprehensive synthesis of the current state of research is needed to understand the pandemic’s impact on human mobility and corresponding government measures. This study examined the relevant literature published to the present (March 2023), identified research trends, and conducted a systematic review of evidence regarding transport’s response to COVID-19. We identified key research agendas and synthesized the results, examining: (1) mobility changes by transport modes analyzed regardless of government policy implementation, using empirical data and survey data; (2) the effect of diverse government interventions to reduce mobility and limit COVID-19 spread, and controversial issues on travel restriction policy effects; and (3) future research issues. The findings showed a strong relationship between the pandemic and mobility, with significant impacts on decreased overall mobility, a remarkable drop in transit ridership, changes in travel behavior, and improved traffic safety. Government implemented various non-pharmaceutical countermeasures, such as city lockdowns, travel restrictions, and social distancing. Many studies showed such interventions were effective. However, some researchers reported inconsistent outcomes. This review provides urban and transport planners with valuable insights to facilitate better preparation for future health emergencies that affect transportation.

This study proposes a policy for urban railway travel demand management system in order to decrease the load factor of the Seoul metro Circle line, particularly for the segment between Sadang and Samsung stations, through analyzing the transit smart card data. We propose mixed train operations of the existing Circle line and a line that goes toward Samsung station in order to transport passengers that have two distinct groups: those with the destination of Samsung station and those with destinations after Samsung station. The introduction of a mixed train operation that encourages passengers passing through Samsung station to take a Circle line train will decrease the congested load factor by 11.3% during the morning peak hours using the mixed train operation of the Circle and Samsung lines. This policy could be an effective method to decrease the load factor and improve the comfort of rail passengers without extra investment in the railway facilities.

Following the success of the KTX (Korea's first high-speed rail system) with a maximum operating speed of 300 km/h opened in 2004, experts in Korea started a research on the development of key technologies for high-speed rail (HSR) with a top speed of 500 km/h. This paper is a preliminary analysis of the research. It first reviews HSR experiences around the world, in terms of traffic and economic impacts of HSR, and presents a preliminary analysis of 500 km/h HSR in Korea. It is estimated that introduction of 500 km/h HSR with a 54% of travel time reduction will increase HSR passengers to about 9.8 million (about 78% of market share) between Seoul and Busan. It is a 23% of growth compared to the base scenario. Along with conventional rail passengers, air passengers are expected to be significantly impacted by the 500 km/h HSR. As a function of HSR travel time, the estimated market shares of both KTX and 500 km/h HSR compared to air are very comparable with previous international experiences. Based on the forecasted traffic, estimated total benefits are $758 million per year.

Rapid demographic ageing is a global challenge and has tremendous implications for transportation planning, because the mobility of elderly people is an essential element for active ageing. Although many studies have been conducted on this issue, most of them have been focused on aggregated travel patterns of the elderly, limited in spatiotemporal analysis, and most importantly primarily relied on sampled (2–3%) household travel surveys, omitting some trips and having concerns of quality and credibility. The objectives of this study are to present more in-depth analysis of the elderly’s spatiotemporal activity and travel behaviors, to compare them with other age and gender groups, and to draw implications for sustainable transportation for the elderly. For our analysis, we used locational trajectory-based mobile phone data in Gangnam, Korea. The data differs from sampled household travel survey data, as mobile phone data represents the entire population and can capture comprehensive travelers’ movements, including peculiarities. Consistent with previous researches, the results of this study showed that there were differences in activity and travel patterns between age and gender groups. However, some different results were obtained as well: for instance, the average nonhome activity time per person for the elderly was shorter than that of the nonelderly, but the average numbers of nonhome activities and trips were rather higher than those of nonelderly people. The results of this study and advantage of using mobile phone data will help policymakers understand the activities and movements of the elderly and prepare future sustainable transportation.