Search results for "Travel time"
showing 5 items of 25 documents
Neighborhood resources associated with active travel in older adults: A cohort study in six European Countries
2020
Objectives: To study associations between perceived neighborhood resources and time spent by older adults in active travel. Methods: Respondents in six European countries, aged 65–85 years, reported on the perceived presence of neighborhood resources (parks, places to sit, public transportation, and facilities) with response options “a lot,” “some,” and “not at all.” Daily active travel time (total minutes of transport-related walking and cycling) was self-reported at the baseline (n = 2,695) and 12–18 months later (n = 2,189). Results: Reporting a lot of any of the separate resources (range B’s = 0.19–0.29) and some or a lot for all four resources (B = 0.22, 95% confidence interval [0.09, …
A branch-and-cut algorithm for the Team Orienteering Problem
2017
The Team Orienteering Problem aims at maximizing the total amount of profit collected by a fleet of vehicles while not exceeding a predefined travel time limit on each vehicle. In the last years, several exact methods based on different mathematical formulations were proposed. In this paper, we present a new two-index formulation with a polynomial number of variables and constraints. This compact formulation, reinforced by connectivity constraints, was solved by means of a branch-and-cut algorithm. The total number of instances solved to optimality is 327 of 387 benchmark instances, 26 more than any previous method. Moreover, 24 not previously solved instances were closed to optimality.
The emission reduction potentials of First Generation Electric Aircraft (FGEA) in Finland
2020
Under the looming climate crisis, aviation needs to find new solutions to cut its greenhouse gas emissions. One pathway towards zero emissions is the use of electric aircraft. While current battery technology will not allow for medium and long-haul flights at full capacity, on short-haul routes First Generation Electric Aircraft (FGEA) could play a significant role in the near future. Current FGEA under development could carry 9–19 passengers on distances of 400–1046 km by 2025. This study focuses on the emissions reduction potentials of FGEA in Finland. It compares the carbon dioxide equivalent (CO2-eq) emissions and real travel times (RTT) from door-to-door of FGEA on 47 routes with exist…
Replacing short-haul flights with land-based transportation modes to reduce greenhouse gas emissions: the case of Finland
2019
Even though air travel often provides the fastest transport option, it also has the highest climate impact. Especially on long-haul trips, an aircraft usually represents the only feasible option. Nevertheless, aircraft are more often used on short-haul routes as well. It is the short-haul flights that produce the highest emissions per passenger. These are also the ones that could be replaced the most easily by land-based transportation modes. This study investigates the greenhouse gas emissions reduction potential of replacing short-haul flights with train, coach and car travel within Finland while also taking into account real travel times from door to door. Our results showed that replaci…
The emissions reduction potential of substituting short-haul flights with non-high-speed rail (NHSR) : The case of Finland
2021
Replacing short-haul flights with high-speed rail (HSR) has been widely discussed as one solution to mitigate the climate change impacts of aviation. However, although HSR can provide travel times similar to those provided by short-haul flights, and at lower emission levels, it also requires considerable investments in time and infrastructure to build. Instead, this study considers the feasibility of replacing short-haul flights with existing non-high-speed rail (NHSR). Our study is based in Finland, a country that has an extensive route network of short-haul flights but does not possess any HSR. We compared all 16 city pairs for which short-haul flights are offered with existing NHSR based…