Travel Distance Research Articles

A Hybrid Adaptive Simulated Annealing and Tempering Algorithm for Solving the Half-Open Multi-Depot Vehicle Routing Problem

The half-open multi-depot vehicle routing problem (HOMDVRP) is a typical decision optimization problem in the field of collaborative logistics that considers resource sharing. This study aims to develop an effective meta-heuristic algorithm for solving the HOMDVRP. Firstly, a mixed-integer programming model of HOMDVRP is established to minimize the total travel distance of the vehicles. After that, a novel hybrid adaptive simulated annealing and tempering algorithm (HASATA) is proposed based on the features of HOMDVRP. The proposed algorithm combines the strengths of the simulated annealing algorithm and the large-neighborhood search algorithm to balance the algorithm’s searching capabilities in both breadth and depth. Meanwhile, an adaptive Markov chain length mechanism and a tempering mechanism are designed to improve the algorithm’s computational efficiency and convergence ability. Finally, simulation experiments are conducted to verify the effectiveness of the proposed model and the computational performance of the proposed algorithm. Four comparison algorithms are selected and analyzed using 24 groups of problem instances. The comparison results show that the proposed HASATA can solve the HOMDVRP more efficiently and obtain a solution with better optimization performance and satisfactory stability.

Exploring the changes of individuals’ travel behavior in response to COVID-19 and their influencing factors based on mobile phone data

IntroductionThe COVID-19 pandemic has produced a profound impact on travel behavior. Yet, few studies explored how individuals resist such impact to maintain their daily life from the perspective of people's responses. A comprehensive theoretical framework to elucidate individual travel behavior changes and a quantitative analysis of the pivotal factors driving these changes was lacking. MethodsThis study constructed a framework for individuals' travel behavior in response to COVID-19 and utilized anonymized mobile phone trajectory data before and during COVID-19 in Guangzhou to explore the changes of individuals’ travel behavior on workdays. Gradient boosting decision trees was used to quantify the degree of the factors driving travel changes. ResultsDuring the pandemic workdays, non-essential trips experienced a reduction of 51.4%, while essential trips decreased by 30.94%; Subway trips decreased by 1.63%, whereas motorized trips increased by 8.75%. The most significant decrease was observed in travel duration (50.92%), followed by travel frequency (41.28%), and travel distance (39.19%). The three travel indices displayed significant social disparities and spatial disparities. However, the relative relationships among these three travel indices did not vary with groups and spaces. Risk perception and intervention measures, emerged as primary drivers of individuals’ travel changes, contributing to 27%–35% of the total impact, while individual socio-economic characteristics and built environment accounting for less than 10%. ImplicationsThe results indicated that individuals curtailed both their essential and non-essential trips and adjusted their travel mode in response to the epidemic. These changes in travel purpose and mode led to differing reduction rates in travel frequency, duration, and distance. These findings contribute to individual travel changes prediction and fine-grained epidemic modelling during other public health emergencies like COVID-19.

The Solution of Traveling Salesman Problem with Time Windows by MILP in Matlab Code

A delivery driver uses his truck to distribute ordered goods from the warehouse (depot) to n customers. Each customer determines the delivery point (by GPS coordinates) and time window for the distribution of goods. This problem can be called the traveling salesman problem with time windows (TSPTW). The objective of the solution is to select the sequence of delivery points so that the travel distance and the total travel time are minimal. The necessary condition is that the deliverer leaves the warehouse, visits all delivery points (where he arrives at the required time windows), and returns to the warehouse. In this article, one exact robust solution of the TSPTW is presented by using mixed integer linear programming implemented in Matlab code. The created algorithm can be used for any number n of customers.

Economic Valuation of Tourist Attractions with Travel Cost Approach

Umbul Sidomukti is an excellent tourist area with several tourist objects. Umbul Sidomukti tourism was designated as a tourist attraction because the area has a potential economic value from the tourism sector. This study aims to determine the economic value of the Umbul Sidomukti tourist attraction based on the travel cost method (TCM). This study uses the travel cost method based on primary data from in-person interviews and online surveys with 105 visitors visiting the Umbul Sidomukti tourist area. The study results show that the relationship between travel costs and distance and the number of tourist visits has a ceteris paribus negative relationship following tourism demand. Service and income variables have a positive effect that is not significant. Meanwhile, the potential economic value of the Umbul Sidomukti tour is estimated at Rp. 28,142,763,075 per year. This research can be used to develop natural tourism objects using the travel cost approach, especially the Umbul Sidomukti tourism object.

Geospatial methodology for determining the regional prevalence of hospital-reported childhood intussusception in patients from India

Both developed and developing countries carry a large burden of pediatric intussusception. Sentinel site surveillance-based studies have highlighted the difference in the regional incidence of intussusception. The objectives of this manuscript were to geospatially map the locations of hospital-confirmed childhood intussusception cases reported from sentinel hospitals, identify clustering and dispersion, and reveal the potential causes of the underlying pattern. Geospatial analysis revealed positive clustering patterns, i.e., a Moran’s I of 0.071 at a statistically significant (p value < 0.0010) Z score of 16.14 for the intussusception cases across India (cases mapped n = 2221), with 14 hotspots in two states (Kerala = 6 and Tamil Nadu = 8) at the 95% CI. Granular analysis indicated that 67% of the reported cases resided < 50 km from the sentinel hospitals, and the average travel distance to the sentinel hospital from the patient residence was calculated as 47 km (CI 95% min 1 km–max 378 km). Easy access and facility referral preferences were identified as the main causes of the existing clustering pattern of the disease. We recommend designing community-based surveillance studies to improve the understanding of the prevalence and regional epidemiological burden of the disease.

Are electric vehicles really the optimal option for the transportation sector in China to approach pollution reduction and carbon neutrality goals?

Profound worldwide fleet electrification is thought to be the primary route for achieving the target of carbon neutrality. However, when and how electrification can help mitigate environmental impacts and carbon emissions in the transport sector remains unclear. Herein, the overall life-cycle environmental impacts and carbon saving range of two typical A-class vehicles in China, including electric vehicle (EV) and internal combustion engine vehicle (ICEV), were quantified by the life cycle assessment model for endpoint damage with localization parameters. The results showed that the EV outperformed the ICEV for the total environment impact after a travel distance of 39,153 km and for carbon emissions after 32,292 km. The ICEV was more carbon-friendly only when the driving distance was less than 3229 km/a. Considering a full lifespan travel distance of 150,000 km, the whole life-cycle average environmental impacts of EV and ICEV were calculated as 8.6 and 17.5 mPt/km, respectively, but the EV had 2.3 times higher impacts than the ICEV in the production phase. In addition, the EV unit carbon emission was 140 g/km, 46.8% lower than that of the ICEV. Finally, three potential reduction scenarios were considered: cleaner power mix, energy efficiency improvement and composite scenario. These scenarios contributed 19.1%, 13.0% and 32.1% reductions, respectively. However, achieving carbon peak and neutrality goals in China remains a great challenge unless fossil fuels are replaced by renewable energy. The research can provide scientific reference for the method and practice of emission reduction link identification, eco-driving choice and emission reduction path formulation.

Effects of Front Total Toe-In Angle on Tire Wear and Emissions for a Light-Duty Vehicle

An experimental investigation is carried out in this study to investigate the effect of wheel alignment, particularly the front total toe-in angle, on tire wear and emissions for a light-duty vehicle. Such investigations reveal that there is a substantial correlation among rolling resistance, energy consumption, tire wear, tire travel life, and the total toe-in angle of the front wheel. It is observed that the rate of loss in tire travel life with regard to a condition without misalignment is up to 98.33% when the front total toe-in angle is out of alignment (ranging from 0.00° to 4.20°). It is found that rolling resistance increases by about 128.86%, while CO2, CO, and NOx emissions rise by nearly 36.67%, 26.83%, and 31.25%, respectively, as the front total toe-in angle increases from 0.00° to 4.20°. The experimental results also reveal that tire circumferential groove wear is observed at 0.04 mm after the vehicle’s travelling distance of 500 km, where the front total toe-in angle is 0.00°, and the tire travelling life is 92250 km. In addition, the tire circumferential groove wear is investigated as 2.40 mm after the vehicle’s travelling distance and tire travel life are recorded to be 3,500 km and 1537.50 km, respectively, due to the occurrence of misalignment (the front total toe-in angle is 4.20°). Finally, a regression model is proposed using the test data. Such a model would be useful to explain the relationship between the related factors and determine the rate of tire wear and emissions. It is noteworthy that the wheels should always remain aligned in accordance with the manufacturer’s specifications in order to ensure optimal performance and longevity of the tires

Rural Native Veterans' Perceptions of Care in the Context of Navigator Program Development.

American Indian and Alaska Natives serve in the military at one of the highest rates of all racial and ethnic groups. For Veterans, the already significant healthcare disparities Natives experience are aggravated by barriers to accessing care, care navigation, and coordination of health care within the Veterans Health Administration (VHA) between the VHA and tribal health systems. To mitigate these barriers, the VHA is developing a patient navigation program designed specifically for rural Native Veterans. We describe formative work aimed at understanding and addressing barriers to VHA care from the perspective of rural Native Veterans and those who facilitate their care. Thirty-four individuals participated in semi-structured interviews (22 Veterans, 6 family members, and 6 Veteran advocates) drawn from 9 tribal communities across the US. Participants described many barriers to using the VHA, including perceptions of care scarcity, long travel distances to the VHA, high travel costs, and bureaucratic barriers including poor customer service, scheduling issues, and long waits for appointments. Many Veterans preferred IHS/tribal health care over the VHA due to its proximity, simplicity, ease of use, and quality. Rural Native Veterans must see a clear benefit to using the VHA given the many obstacles to its use. Veteran recommendations for addressing barriers to VHA care within a navigation program include assistance enrolling in, scheduling, and navigating VHA systems; paperwork assistance; cost reimbursement; and care coordination with the IHS/tribal health care.

What happens to rural hospitals during a ransomware attack? Evidence from Medicare data.

Hospitals are increasingly the target of cybersecurity threats, including ransomware attacks. Little is known about how ransomware attacks affect care at rural hospitals. We used data on hospital ransomware attacks from the Tracking Healthcare Ransomware Events and Traits database, linked to American Hospital Association survey data and Medicare fee-for-service (FFS) claims data from 2016 to 2021. We measured Medicare FFS volume and revenue in the inpatient, outpatient, and emergency room setting-at the hospital-week level. We then conducted a stacked event study analysis, comparing hospital volume and revenue at ransomware-attacked and nonattacked hospitals before and after attacks. Ransomware attacks severely disrupted hospital operations-with comparable effects observed at rural versus urban hospitals. During the first week of the attack, inpatient admissions volume fell by 14.7% at rural hospitals (P=.04) and 16.9% at urban hospitals (P=.01)-recovering to preattack levels within 2-3 weeks. Outpatient visits fell by 35.3% at rural hospitals (P<.01) and 22.0% at urban hospitals (P=.03) during the first week. Emergency room visits fell by 10.0% at rural hospitals (P=.04) and 19.3% at urban hospitals (P=.01). Travel time and distance to the closest nonattacked hospital was 4-7 times greater for rural ransomware-attacked hospitals than for urban ransomware-attacked hospitals. Ransomware attacks disrupted hospital operations in rural and urban areas. Disruptions of similar magnitudes may be more detrimental in rural areas, given the greater distances patients must travel to receive care and the outsized impact that lost revenue may have on rural hospital finances.

Sustainable waste collection optimization using electric vehicles

Solid waste management is a crucial municipal service directly influencing urban livability. Optimizing refuse collection routes enhances service efficiency and reduces costs. The recent introduction of fully electric refuse trucks, boasting features like zero emissions, low noise, and lower operating costs compared to diesel trucks, holds promise. However, their limited autonomy presents challenges that need addressing before widespread deployment. This study proposes a realistic formulation for the refuse collection routing problem with electric trucks, introducing electromobility constraints never considered before in related works. The goal is to find optimal routes covering all collection points while minimizing travel distance within vehicle battery and capacity limits. An accurate energy consumption model is presented, accounting for route elevation, vehicle speed, waste collection operations, and regenerative braking. Genetic algorithms are used to find solutions to the problem, as well as the well-known Clarke and Wright heuristic for comparison purposes. The algorithms are tested on six diverse instances reflecting real-world scenarios in New York City (United States) and Puerto Real (Spain). Results indicate the genetic algorithm’s superiority, yielding solutions with reduced travel distance and consumption while requiring fewer routes compared to the state-of-the-art heuristic.

Perspectives of patients, parents, and health care providers on facilitators of and barriers to the transition from pediatric to adult care in inflammatory bowel disease: a qualitative descriptive study.

The typical transition from pediatric to adult care in patients with inflammatory bowel disease occurs with an increase in health care utilization and a decrease in adherence to medications and scheduled appointments. An effective transition could reduce negative impacts but requires identifying opportunities to improve this process. This study aims to describe barriers and facilitators of transition according to patients, parents, and health care providers. This study used a qualitative description approach. The lead author conducted semi-structured interviews with 17 patients, 13 parents, and 15 providers recruited from Western Canada. Latent content analysis identified themes in interview transcripts. The theme of preparedness emerged across all groups as a transition facilitator. Other facilitators that emerged included patient characteristics, supportive parents, home environment, and supportive adult care team. Themes of barriers that emerged included patient factors, "hovering parents" and family factors, navigating a new health care system, and travel distance. This study describes facilitators and barriers according to each stakeholder involved in the transition process. Future studies should focus on designing and evaluating interventions aimed at promoting facilitators and addressing identified barriers in patients preparing to transition from pediatric to adult care.

The effects of long-term exposure to microgravity and body orientation relative to gravity on perceived traveled distance

Self-motion perception is a multi-sensory process that involves visual, vestibular, and other cues. When perception of self-motion is induced using only visual motion, vestibular cues indicate that the body remains stationary, which may bias an observer’s perception. When lowering the precision of the vestibular cue by for example, lying down or by adapting to microgravity, these biases may decrease, accompanied by a decrease in precision. To test this hypothesis, we used a move-to-target task in virtual reality. Astronauts and Earth-based controls were shown a target at a range of simulated distances. After the target disappeared, forward self-motion was induced by optic flow. Participants indicated when they thought they had arrived at the target’s previously seen location. Astronauts completed the task on Earth (supine and sitting upright) prior to space travel, early and late in space, and early and late after landing. Controls completed the experiment on Earth using a similar regime with a supine posture used to simulate being in space. While variability was similar across all conditions, the supine posture led to significantly higher gains (target distance/perceived travel distance) than the sitting posture for the astronauts pre-flight and early post-flight but not late post-flight. No difference was detected between the astronauts’ performance on Earth and onboard the ISS, indicating that judgments of traveled distance were largely unaffected by long-term exposure to microgravity. Overall, this constitutes mixed evidence as to whether non-visual cues to travel distance are integrated with relevant visual cues when self-motion is simulated using optic flow alone.

Travel distance and outcomes after surgical aortic valve among veterans.

To investigate the association between travel distance and postoperative length of stay (LOS) and discharge disposition among veterans undergoing surgical aortic valve replacement (SAVR). We performed a retrospective cohort study of patients undergoing SAVR, with or without coronary artery bypass grafting (CABG) at VA Boston Healthcare (January 1, 2005-December 31, 2015). Postoperative LOS and discharge disposition were compared for SAVR patients based on travel distance to the facility: <100 miles or ≥100 miles. Multivariable regression was performed to ascertain factors associated with LOS and home discharge. Data were collected via chart review. All patients undergoing SAVR at our institution who primarily resided within the defined region were included. Of 597 patients studied, 327 patients underwent isolated SAVR; 270 patients underwent SAVR/CABG. Overall median (IQR) distance between the patient's residence and the hospital was 49.95 miles (27.41-129.94 miles); 190 patients (32%) resided further than 100 miles away. There were no differences in the proportion of patients with diabetes, hypertension, chronic obstructive pulmonary disease (COPD), cerebrovascular disease, atrial fibrillation, or prior myocardial infarction between groups. Overall LOS (IQR) was 9 (7-13) days and did not differ between groups (p = 0.18). The proportion of patients discharged home was higher among patients who resided more than 100 miles from the hospital (71% vs. 58%, p = 0.01). On multivariable analysis, residing further than 100 miles from the hospital was independently associated with home discharge (OR = 1.64, 95% CI: 1.09-2.48). Travel distance was not associated with LOS. Based on our institutional experience, potential concerns of longer hospital stay or discharge to other inpatient facilities for geographically distanced patients undergoing SAVR do not appear supported. Continued examination of the drivers underlying the marked shift of veterans to the private sector appears warranted.

Estimating maximum initial wave amplitude of subaerial landslide tsunamis: A three-dimensional modelling approach

Landslide tsunamis, responsible for thousands of deaths and significant damage in recent years, necessitate the allocation of sufficient time and resources for studying these extreme natural hazards. This study offers a step change in the field by conducting a large number of three-dimensional numerical experiments, validated by physical tests, to develop a predictive equation for the maximum initial amplitude of tsunamis generated by subaerial landslides. We first conducted a few 3D physical experiments in a wave basin which were then applied for the validation of a 3D numerical model based on the Flow3D-HYDRO package. Consequently, we delivered 100 simulations using the validated model by varying parameters such as landslide volume, water depth, slope angle and travel distance. This large database was subsequently employed to develop a predictive equation for the maximum initial tsunami amplitude. For the first time, we considered travel distance as an independent parameter for developing the predictive equation, which can significantly improve the predication accuracy. The predictive equation was tested for the case of the 2018 Anak Krakatau subaerial landslide tsunami and produced satisfactory results.

Sustainable urban logistics: A case study of waterway integration in Amsterdam

This paper tackles the growing challenges in urban logistics by presenting an optimal distribution network that integrates urban waterways and last-mile delivery, tailored for cities boasting extensive waterway networks. We examine Amsterdam's city center as a case study, prompted by the strain on quay walls, congestion, and emissions, urging a reevaluation of its urban logistics design. We formulate the problem as a two-echelon location routing problem with time windows and introduce a hybrid solution approach for effective resolution. Our algorithm consistently outperforms existing methods, with a superior solution quality, demonstrating its effectiveness across established and newly developed benchmark instances. In our case study, we evaluate the benefits of transitioning from a roadway-centric to a waterway-based system, showcasing significant cost savings (approximately 28 %), reductions in vehicle weight (approximately 43 %), and minimized travel distances (approximately 80 %) within the city center. The integration of electric vehicles enhances environmental sustainability, resulting in a total daily emission reduction of 43.46 kg. Our study underscores the untapped potential of inland waterways in easing urban logistics challenges. Inspired by Amsterdam's experience, global cities can adopt innovative approaches for sustainable logistics, providing valuable insights for managers striving to enhance efficiency, cut costs, and promote sustainable transportation practices.

Synchronizing crowdsourced co-modality between passenger and freight transportation services

This study introduces a synchronized passenger and freight co-modality problem (SPFCP), exploring a crowdsourced co-modality transportation mode where passengers, viewed as an external crowd, volunteer to participate in logistics activities in exchange for compensation. In SPFCP, decision-makers have the option to utilize both crowdsourced passengers (CPs) and self-operated professional couriers (PCs) for deliveries. We formalize the problem and employ a population-based variable neighborhood search to solve it. Our findings indicate that the availability of CPs crucially enhances delivery capacity and efficiency, with the system benefiting from a larger pool of CPs and a higher variability in their travel distances. However, challenges arise from extreme average parcel distances, necessitating precise matching for short distances and extensive crowdsourced resources for long distances. The study underscores the viability of integrating crowdsourced logistics into urban transport systems, suggesting a strategic balance between leveraging crowdsourced solutions and managing logistical complexities.

Effects of Travel Distance on Complications and Outcomes in Total Ankle Arthroplasty.

Owing to the last decade's increase in the number of total ankle arthroplasty (TAA) procedures performed annually, there is a concern that the disproportionate distribution of orthopaedic surgeons who regularly perform TAA may impact complications and/or patient satisfaction. This study examines patient-reported outcomes and complications in TAA patients who had to travel for surgery compared to those treated locally. This is a single-center retrospective review of 160 patients undergoing primary TAA between January 2016 and December 2018, with mean age 65 (range: 59-71) years, mean body mass index (BMI) 28.7 kg/m2, 69 (43.1%) females, and mean 1.5 (SD = 0.51) years follow-up. Patients were grouped by distance traveled (<50 miles [n = 89] versus >50 miles traveled [n = 71]). There were no significant differences in rate or type of postoperative complications between the <50 mile group (16.9%) and the >50 mile group (22.5%) (P = .277). Similarly, there were no significant difference in postoperative PROMIS scores between the groups (P = .858). Given uneven distribution of high-volume surgeons performing TAA, this is important for patients who are deciding where to have their TAA surgery and for surgeons on how to counsel patients regarding risks when traveling longer distances for TAA care.Levels of Evidence: Level III: Retrospective Cohort Study.

Network-entropy-based morphological polycentricity in 1851-1881 England and Wales

A system of cities is morphologically polycentric when its cities are similarly sized and evenly spaced across its territory. In this paper, we adapt established spatial interaction models and entropy-based measures of heterogeneity of weighted networks to the problem of measuring morphological polycentricity. We study the evolution of the morphological polycentricity of the system of English and Welsh towns from 1851 to 1881, a period characterised by rapid urbanisation and expansion of railways. Our approach enables us to account for morphological aspects of the system that are often neglected by existing measures of morphological polycentricity, such as the evolution of transport infrastructure and its impact on travel distances. We show that the trend towards a greater concentration of the population in fewer urban centres in England and Wales was accompanied by a more diverse network of connections and potential intercity interactions.

Quantifying the relationship between mobility patterns and socioeconomic status of dockless bike-sharing users

Cycling is among the healthiest, greenest, and most affordable means of transportation for a better future city, but mobility patterns of cyclists with different income have rarely been studied due to the limitation of data availability. Newly emergent dockless bike-sharing platforms that record detailed trip information provide us a unique opportunity. Attributing to its better usage flexibility and accessibility, dockless bike-sharing is booming over the past few years worldwide and reviving the cycling fashion in cities. In this work, by exploiting massive platform-collected trip records in four diversified Chinese cities, we reveal that individual mobility patterns, including radius of gyration and average travel distance, are similar among the users with different income, indicating that human beings all follow similar physical rules. However, collective mobility patterns, in terms of average range and diversity of visitation, and commuting direction, exhibit different behaviors and spatial patterns across income categories. Hotspot locations that attract a high volume of cycling activities are quite different over groups, and locations with either a lower or higher income level have a relatively low user ratio. Cyclists from lower income groups are inclined to visit less flourishing locations across all four cities, and have a higher fraction to commute toward the city center in larger cities and away from the city center in smaller cities. Middle income groups of cyclists generally have a higher visitation diversity except in Shanghai. Our findings would be helpful on designing better promotion strategies for dockless bike-sharing platforms and toward the transition to a more inclusive and sustainable transportation.

Connecting classic cycle tourism with micromobiles - Case study of the Autonomous Province of Vojvodina

Connecting classic cycle tourism with micromobiles - Case study of the Autonomous Province of Vojvodina