Excess Travel Time Research Articles

Riding transit to parks in Utah: Motivations, constraints, negotiations, and policy recommendations

In this paper, we studied the motivations, constraints, negotiations, and policy changes for riding transit to parks in Utah’s Wasatch Front region, exploring how these factors vary between disadvantaged and non-disadvantaged individuals. This is one of the first studies to explore transit-to-parks experiences in large urban regions. We conducted interviews with 25 diverse transit riders. Motivations for riding transit to parks included environmental concerns and the convenience of avoiding parking and traffic. Constraints involved excessive travel time due to limited service, transit frequency and reliability issues, and last-mile connection issues. The main negotiation strategy was to plan trips to limit travel time. People in low-income neighborhoods had limited transit-to-parks services, and available services were adequate for fit and non-disabled people. Policy changes that would help participants address constraints included new or modified routes, improved last-mile connections, information and marketing campaigns, and better service for low-income communities and people with disabilities.

Public Transport Prioritization and Descriptive Criteria-Based Urban Sections Classification on Arterial Streets

The present paper is aimed at improving minimization methods in traffic flows, particularly reducing the costs of civil transportation through sections of the transport network by giving priority to public transport in densely developed areas. In cities with a radial and radial–circular planning scheme of the road network, where arterial traffic flows converge in the central part, the challenge of street congestion with traffic often arises. As a result, delays of all types of vehicles increase, which causes excessive travel time for users of private and public transport. In this regard, it is proposed to divide the sections of the transport network into eight types based on their geometric parameters and traffic conditions. This differentiation of sections improves the existing methods for determining the spatial delay of traffic flows on sections of the transport network with different parameters. It was achieved by considering the duration of vehicles passing signalized intersections and pedestrian crosswalks and the sections of streets between them, while simultaneously recording the duration of public transport movement, as well as the time they spend at stopping points, using GPS receivers. The results of onsite monitoring and further computations revealed that there are particular urban sections with specific, different distances between adjacent stop lines that are critical for public transport operation. Furthermore, based on the delay criterion, there were three different passage modes proposed to improve the efficiency of the traffic.

A joint optimisation model for charger locating and electric bus charging scheduling considering opportunity fast charging and uncertainties

The continuous improvement of charging technologies makes fast charging applicable to overcoming the limited driving range of electric vehicles by providing en-route opportunity charging. Fast chargers can be deployed at bus stops to top up the battery for an electric bus during its dwelling time when passengers board and alight, which allows the usage of small size battery and avoids deadheading trips to depot or charging station for recharging. This paper examines the joint optimisation problem of locating fast chargers at selected bus stops and developing charging schedule to support electric bus operation considering time-varying electricity price and penalty cost if passengers’ extra waiting time, the delay time of starting a trip or the excessive travel time of completing a trip is caused by charging activities. To handle the uncertainties associated with the travel time and passenger demand, a robust model is proposed and formulated. The proposed methods are applied to multiple bus routes in Sydney in the numerical studies. The numerical results show that frequent charging activities occur at both intermediate and last stops during bus service trips, indicating that it is beneficial for buses to utilise passengers’ boarding and alighting time at intermediate stops and resting time at the last stop between two adjacent trips to top up battery. Sensitivity analysis on a series of system parameters, such as the acquisition cost of chargers, amortized battery price and charging power, is conducted. The numerical results verify the feasibility of deployment of fast chargers and corresponding top-up charging activities at both intermediate and last stops. Electric buses outperform the conventional diesel buses regarding energy consumption cost, especially considering the increasing diesel fuel price and its costly environmental impacts. Moreover, charging activities at intermediate stops will become more common when passenger demand (the volume of boarding and alighting passengers) increases at intermediate stops.

Resilience Assessment of a Twin-Tube Motorway Tunnel in the Event of a Traffic Accident or Fire in a Tube

We have developed a traffic simulation model to quantitatively assess the resilience of a twin-tube motorway tunnel in the event of traffic accident or fire occurring within a tube. The motorway section containing the tunnel was investigated for different possible scenarios including its partial or complete closure. The functionality of the road infrastructure, in the case of an accident in one of the two tubes (each tube presents two lanes with unidirectional traffic under ordinary conditions), was assumed to be recovered both by using the remaining undisrupted lane of the tube interested by the disruptive event (only one lane is closed) and reorganizing the traffic flow by utilizing the adjacent tube for bi-directional traffic (both lanes are closed). The effects of an alternative itinerary individualized in the corresponding open road network were also examined. The level of functionality of the system during the period in which the tube is partially or completely closed was computed as the ratio between the average travel time required to reach a given destination from a specific origin before and after the occurrence of the disruptive event. The resilience metrics were assumed to be resilience loss, recovery speed, and resilience index. The best scenario was found to be the partial closure of the tube in contrast to the complete one. However, in order to contain the negative effects on the functionality of the motorway section due to the complete closure of the tube, it is worth highlighting how the traffic by-pass before the entrance portal of the closed tube should be open in a very short time by the tunnel management team to allow for the quick use of the adjacent tube for bi-directional traffic. An additional improvement, with reference exclusively to passenger cars traveling through the adjacent unblocked tube, might be obtained by activating the variable message signs, located at a sufficient distance from the motorway junction before the entrance portal of the closed tube, in order to suggest an alternative route to heavy good vehicles (HGVs) only. Whereas, when the alternative itinerary is used by all vehicles traveling towards the blocked tube (i.e., both passenger cars and HGVs), this redirectioning of the motorway traffic flow was found to be characterized by an excessive travel time, with it therefore not being advisable. The results obtained might be useful as a decision-making support tool aimed at improving the resilience of twin-tube tunnels.

Studies of the effectiveness of transport sector interventions in low- and middle-income countries: An evidence and gap map.

Studies of the effectiveness of transport sector interventions in low- and middle-income countries: An evidence and gap map.

A data-driven approach to scheduling the U.S. presidential primary elections

In this article we formulate and solve a model for choosing the grouping and ordering of state primary elections for a United States presidential election cycle. Our work fills a gap in the existing literature by defining a reproducible procedure for deriving an entire schedule of U.S. primary elections in a way that meets quantifiable goals of efficiency, equity, and effectiveness.Our model considers each state's attributes and gives higher priority to states whose voting and demographic profiles more closely reflect those of the county as a whole. It also clusters states into primary dates in a way that spreads the electorate relatively evenly over the primary season. Finally, the clustering process takes proximity into account, so that political campaigns can focus more effectively on a particular region without incurring excessive travel time. Since these criteria may conflict, the preferred ordering depends on the tradeoffs made among the goals. We highlight two solutions in which states with voting and demographic attributes close to those of the national profile are scheduled early on, while the geographic grouping and spread of voters over the schedule are significantly better than those of the status quo.

More than just a bus trip: School busing, disability and access to education in Toronto, Canada

Children with disabilities in Ontario, Canada have their right to equal access to education protected by the 1990 Ontario Human Rights Code and the 1990 Education Act. These legislated rights require the delivery of stigma- and barrier-free education services to children with disabilities. However, the extent to which compliance is achieved by school boards and individual schools is questionable and warrants attention as a matter of both scholarship and public policy. In this paper, we take up and apply the concept of excess travel (i.e., the travel beyond what would be required given a more optimal distribution of housing and schools) to examine the extent to which students with disability and their families are required to undertake longer, more time-consuming school trips. Our analysis includes students who were bused to TDSB elementary (grade school) and secondary (high school) schools. We use TDSB student busing records for the 2016–17 school year obtained in collaboration with the TDSB between December 2017 and March 2018. Our findings indicate substantial excess travel, particularly for students who are labelled as deaf, physically disabled, or having a behavioural exceptionality. Excess travel time experienced by students with disability is concerning given that it can lead to missed classroom time and may limit opportunities for peer interaction. The availability of busing services for students with disability confers access to education, yet it may paradoxically produce disabling experiences.

PROTOCOL: Evidence and gap map: studies of the effectiveness of transport sector interventions in low- and middle-income countries.

PROTOCOL: Evidence and gap map: studies of the effectiveness of transport sector interventions in low- and middle-income countries.

Customized bus route design with pickup and delivery and time windows: Model, case study and comparative analysis

The customized bus (CB) is an emerging type of public transportation system, which not only provides a flexible and reliable demand-responsive service, but also reduces the usage of private car to alleviate traffic congestion in metropolitan cities. The customized bus route design problem (CBRDP) is a crucial procedure in the CB service system designing. In this work, we develop a new type of problem scenario: Multi-Trip Multi-Pickup and Delivery Problem with Time Windows, to describe CBRDP by simultaneously optimizing the operating cost and passenger profit, where excess travel time is introduced to estimate passenger extra cost compared with taxi service, and each vehicle is allowed to perform multiple trips for operational cost savings. To solve this problem, a constructive two-stage heuristic algorithm is presented to obtain the Pareto solution. Taking a benchmark problem and Beijing commuting corridor as case studies, we calculate and compare the monetary and travel costs of CB with other travel modes, and quantitatively confirm that the CB can be a cost-effective choice for passengers.

Network development and excess travel time

We study the impact of airlines network design on excess travel times for the main US carriers between 2008 and 2017 and find that network configuration affects excess travel time. Based on graph theory and a principal component analysis we build four continuous indicators to measure the airlines networks. We observe that airlines serving more destinations, organizing flights landings and take offs around banks or moving towards a point to point configuration present higher levels of excess travel time. However, there does not seem to exist a preferred network configuration between hub and spoke or point-to-point configuration to reduce excess travel time. We also find a nonlinear impact of competition measured at the city-pair level over excess travel time. These results are robust when analyzing observed delays rather than excess travel time.

Patterns of Hospital Bypass and Interhospital Transfer Among Patients With Heart Failure

BackgroundWe describe how patient characteristics influence hospital bypass, interhospital transfer, and in-hospital mortality in patients with heart failure in Washington. Rural patients with heart failure may bypass their nearest hospital or be transferred for appropriate therapies. The frequency, determinants, and outcomes of these practices remain uncharacterized. Methods and ResultsMean excess travel times based on hospital and patient residence ZIP codes were calculated using published methods. Hospitals and servicing areas were coded based on bed size and ZIP code, respectively. Transfer patterns were analyzed using bootstrap inference for clusters. Analysis of mortality and transfer-associated factors was performed using logistic regression with generalized estimating equations. There were 48,163 patients, representing 1106 instances of transfer, studied. The mean excess travel time increased 7.14 minutes per decrease in population density (metropolitan, micropolitan, small town, rural; P < .0001). The rural mean excess travel time was greatest at 28.56 minutes. Transfer likelihood increased with younger age, male gender, admitting hospital rurality, higher Charlson Comorbidity Index, and stroke. Transfer was less likely among women (odds ratio [OR], 0.82; 95% confidence interval [CI], 0.72–0.94) and patients over 70 years old (OR, 0.15–0.46; 95% CI, 0.10–0.65). Adjusting for comorbidities and transfer propensity, transfer exhibited a stronger association with mortality than any other measured patient risk factor (OR, 2.15; 95% CI, 1.69–2.73), excluding stroke (OR, 7.09; 95% CI, 4.99–10.06). ConclusionsRural hospital bypass is prevalent among patients with heart failure, although its clinical significance is unclear. Female and older patients were found to have a lesser likelihood of transfer adjusted for other factors. Interhospital transfer is associated with increased mortality when adjusted for comorbidities.

Identification and evaluation of flood-avoidance routes in Tucson, Arizona

Campaigns such as “Turn Around, Don't Drown®” encourage motorists to avoid driving into flooded roadways, but thousands of flood-vehicle incidents occur each year. Motorists may not have a feasible alternate route, or they may not be aware of one. Furthermore, few studies within hazards research consider how vulnerability changes as an individual moves through space. A survey of Tucson, Arizona residents included a mapping activity to determine whether their typical routes intersect flood areas, and whether alternate routes exist that avoid flood areas without adding excessive travel time. Of the 452 routes provided, 185 intersect with areas known to flood during routine rain events, affecting 80% of participants. ANOVA revealed no statistically significant differences in exposure rate among groups based on demographic characteristics. Network analyst was used to generate alternate routes that avoid the flood areas and to calculate how much additional time and mileage would be required. Most of the alternate routes added less than one mile to the trip, which is within participants' stated detour tolerance. These findings highlight the potential utility of a decision-support tool to help motorists choose safer, flood-avoiding routes during storms.

Multi-Center Validation of a Consensus-Based Scoring Guide for Evaluating Donor Lung Offers

The previously described University of MN Donor Lung Quality Index (UMN-DLQI) score is a consensus-based decision tool that includes 16 risk-related components receiving 0-5 points, with higher scores signifying lower risk. A score >39 is considered favorable for transplant. We evaluated the UMN-DLQI score's performance across a diversity of US lung transplant centers. We modified the UMN-DLQI to include standardized response choices for all parameters to enhance inter rater consistency. A co investigator at each site was trained in UMN-DLQI scoring, including hypothetical donor test cases to ensure proficiency. We included consecutive primary donor offers (age >11) to participating sites between May 1 and October 31, 2016 that were either accepted for transplant or turned down for quality by the participating center. UMN-DLQI scores were calculated after donor acceptance decisions. We excluded donations after circulatory death and turn downs exclusively for size, HLA, known malignancy, unmet multi-organ or laterality needs, other recipient or donor issues, or excess travel time. We explored associations between the UMN-DLQI score with discrepant donor decisions (organs turned down that were subsequently transplanted elsewhere) and recipient outcomes. Eleven centers participated. 183 donor organs were accepted and transplanted. Accepted donors averaged 35 years old and 16% met increased risk criteria. The median UMN-DLQI score was 43 (range 32 - 50). One in five transplanted organs scored <40 (22%). Few accepted donors were heavy smokers (8%), had risk of lung (1%) or other malignancy (5%), or had anticipated surgical complexity (5%). Few accepted offers lost points for low oxygenation (5 %), with a mean PaO2 to FiO2 (P/f) ratio of 424. Likewise, few lost points for risks of pre-existing lung disease (9 %), contusion (16 %), or positive cross match (4 %). However, 38, 24, and 28 % lost points for risk of pulmonary edema, risk of aspiration, and donor age, respectively. Additionally, the majority of accepted donors lost points for an estimated ischemic time >6 hours, donor size mismatch, or pneumonia risk (57, 53, and 61%, respectively). The mean LAS was 45.5. Multi center use of a standardized scoring instrument offers insight into donor acceptance practices and may be useful in understanding discrepant organ decisions in lung transplantation.

A route guidance system considering travel time unreliability

Under a stochastic roadway, drivers need a route guidance system incorporating travel time variability. To recommend a customized path depending on the trip purpose and the driver’s risk-taking behavior, various path ranking methods have been developed. Unlike those methods, our proposed disutility method can easily incorporate a target arrival time in the ranking process by measuring how late the travel is and by penalizing it depending on the severity of lateness. In addition, the disutility-based route guidance system can properly address travel time unreliability that causes unacceptable disruptions to the driver’s schedule (i.e., unexpected long delay). We compare the disutility-based path ranking method with other ranking methods, the percentile travel time, the mean excess travel time, and the on-time arrival probability. We show that the disutility has stronger discriminating power and requires less solution space to find an optimal path. The most important advantage is that it can estimate a driver’s risk-taking behavior for each trip purpose by using the discrete choice analysis. We construct a simulation framework to acquire the travel time data on a hypothetical roadway. We analyze the data and show how various ranking methods recommend a customized path. Using the data, we show the advantage of the disutiltiy method over the other methods, which is generating a customized path with respect to the target arrival time by properly penalizing the travel time lateness.

Assessing travel time reliability implications due to roadworks on private vehicles and public transport services in urban road networks

Abstract Roadworks are perhaps the most controversial topic in transport professional field. On one hand, they are a necessity to assure the current and future functionality of the traffic network, while on the other, they are seen as a major disturbance by road users with concerns for excessive travel time delays. The impact of roadworks is usually analysed at a local level however the network-wide effects are crucial to ensure reliable travel times. Moreover the analysis usually focusses on private cars and the reliability impact on public transport services are too important to ignore. This paper investigates the impact of roadworks undertaken on a given road link over wider parts of the network and assesses travel time reliability for both cars and buses. This research involves setting up of a conventional network assignment model to arrive at the route choice of drivers as a result of the roadworks and then integrates the outcomes with a microsimulation model to generate space-time trajectories to arrive at travel times of individual vehicles. We adopted a reliability measure from the literature to compute travel time reliability of a given type of vehicle by unique origin-destination (O-D) pair combinations and also more generally to provide a wider picture at an aggregated network level. The method was tested on a real life network in England, and travel time reliability results were analysed both at the network scale and significant O-D pair level for private cars and bus routes.

Travel Burden to Breast MRI and Utilization: Are Risk and Sociodemographics Related?

PurposeMammography, unlike MRI, is relatively geographically accessible. Additional travel time is often required to access breast MRI. However, the amount of additional travel time and whether it varies on the basis of sociodemographic or breast cancer risk factors is unknown. MethodsThe investigators examined screening mammography and MRI between 2005 and 2012 in the Breast Cancer Surveillance Consortium by (1) travel time to the closest and actual mammography facility used and the difference between the two, (2) women’s breast cancer risk factors, and (3) sociodemographic characteristics. Logistic regression was used to examine the odds of traveling farther than the closest facility in relation to women’s characteristics. ResultsAmong 821,683 screening mammographic examinations, 76.6% occurred at the closest facility, compared with 51.9% of screening MRI studies (n = 3,687). The median differential travel time among women not using the closest facility for mammography was 14 min (interquartile range, 8-25 min) versus 20 min (interquartile range, 11-40 min) for breast MRI. Differential travel time for both imaging modalities did not vary notably by breast cancer risk factors but was significantly longer for nonurban residents. For non-Hispanic black compared with non-Hispanic white women, the adjusted odds of traveling farther than the closest facility were 9% lower for mammography (odds ratio, 0.91; 95% confidence interval, 0.87-0.95) but more than two times higher for MRI (odds ratio, 2.64; 95% confidence interval, 1.36-5.13). ConclusionsBreast cancer risk factors were not related to excess travel time for screening MRI, but sociodemographic factors were, suggesting the possibility that geographic distribution of advanced imaging may exacerbated disparities for some vulnerable populations.

Regulating vehicle sharing systems through parking reservation policies: Analysis and performance bounds

We study the regulation of one-way station-based vehicle sharing systems through parking reservation policies. We measure the performance of these systems in terms of the total excess travel time of all users caused as a result of vehicle or parking space shortages. We devise mathematical programming based bounds on the total excess travel time of vehicle sharing systems under any passive regulation (i.e., policies that do not involve active vehicle relocation) and, in particular, under any parking space reservation policy. These bounds are compared to the performance of several partial parking reservation policies, a parking space overbooking policy and to the complete parking reservation (CPR) and no-reservation (NR) policies introduced in a previous paper. A detailed user behavior model for each policy is presented, and a discrete event simulation is used to evaluate the performance of the system under various settings. The analysis of two case studies of real-world systems shows the following: (1) a significant improvement of what can theoretically be achieved is obtained via the CPR policy; (2) the performances of the proposed partial reservation policies monotonically improve as more reservations are required; and (3) parking space overbooking is not likely to be beneficial. In conclusion, our results reinforce the effectiveness of the CPR policy and suggest that parking space reservations should be used in practice, even if only a small share of users are required to place reservations.

Impact of transition between signal timing plans in social cost based in delay, fuel consumption and air emissions

Significant effects of traffic congestion include the cost associated with extra travel time, fuel consumption, and gas emissions. This paper develops a mathematical function to quantify the monetary impact of transition designs between signal timing plans on users and the environment. This function offers an approach to reduce problems such as excessive travel time, pollution emissions and fuel consumption. The proposed social cost function is evaluated for various transition plans to assess the impact of the number of steps required to adjust signal timing. The relationships between delay, fuel consumption and gas emissions and the number of steps needed to achieve the transition are also analysed.

A structural equation model based analysis of non-workers’ activity-travel behaviour from a city of a developing country

This paper presents an empirical analysis of non-workers’ activity-travel behaviour from Bangalore city, India. The paper builds a causal model—to describe the relationships among socio-demographics, activity-participation, and travel behaviour of non-workers—following structural equation modelling methodology. The results indicate that in-home maintenance activity-duration drives the time allocation decisions of non-workers. The model also shows the presence of ‘time-budget’ effects i.e., excess travel time cuts into in-hhome discretionary activity duration, implying the trade-off between daily travel time and in-home discretionary activity duration. The out-of-home activity durations of non-workers are found to be insensitive to travel time—an important finding of this research. The model also suggests that mixed residential development reduce travel distance and indirectly contribute to more trips. An indirect effect of mixed residential development on daily travel distance offsets the direct effect, which leads to a limited total effect of this variable on travel distance. The basic model was expanded further by separating the time spent on others’ activity (children and elders) from in-home maintenance activity duration. The stable model reveals that the time spent on others’ activity also influences in-home and out-of-home activities, and travel behaviour. This indicates that the time spent on others’ activity is an important time allocation of its own.

Method for Assessing Bus Delay in Mixed Traffic to Identify Transit Priority Improvement Locations in Cambridge, Massachusetts

Urban transit services face a number of challenges from space constraints, congestion, and delays, among other issues. Implementing bus priority at traffic signals or providing exclusive operating space for buses can increase the attractiveness of taking the bus and thereby encourage ridership. The City of Cambridge, Massachusetts, was looking to pilot such interventions to demonstrate benefits of bus ridership, but needed a prioritized list of route segments with the largest levels of excess travel time to do so. Three metrics were used to evaluate delay: vehicle delay, overall passenger delay, and system reliability. These three metrics were combined into a single composite rating system for each segment and used to identify route segments along which buses experienced the most delay. The City of Cambridge analyzed high-ridership bus routes with automatic passenger counter data to identify segments along the route where buses experienced substantial delay. The next step for this project is to conduct an on-site field visit of targeted segments to develop potential bus prioritization proposals for each. This paper outlines the method developed to calculate bus delay by segment and presents results for one route analyzed.