Last-mile Research Articles

Dockless bike-sharing as a feeder mode of metro commute? The role of the feeder-related built environment: Analytical framework and empirical evidence

The newly prevailing dockless bike-sharing system offers a decent solution to the first- and last-mile problem and connects trip origins/destinations and transit (mostly metro) stations. Few studies, however, have explored the effects of built environment characteristics on the integrated usage of dockless bike-sharing and the metro, especially in different conditions (e.g., access versus egress and morning peak versus evening peak) and using panel data. To fill the gap, this study proposes a people–metro–bike–route–urban space framework to describe the feeder-related built environment from the perspective of the feeder process. Using 3-day data of ofo bikes in Shenzhen, China, this study then develops multilevel negative binomial models that incorporate random effects and address the intracluster correlation attributed to repeated measures to scrutinize the feeder-related built environment effects on the integrated usage. The findings are listed as follows: (1) The majority of access and egress integrated trips have a distance range of 500–2000 m and a duration range of 2.5–10 min; (2) Popular metro stations (with a large ridership) are positively related to the access integrated usage; (3) The number of available shared bikes and the length of bikeway in the catchment areas of the metro are positively related to the integrated usage; and (4) Mixed land use increases the integrated usage, whereas urban villages are places with few demands for the integrated usage. These findings are beneficial in developing a bike-friendly built environment that facilitates the seamless connection between dockless bike-sharing and the metro.

Addressing the New Last-Mile Problem in Health Care With Home-Based Complex Diagnostics

Addressing the New Last-Mile Problem in Health Care With Home-Based Complex Diagnostics

Analyzing the structural properties of bike-sharing networks: Evidence from the United States, Canada, and China

Abstract To solve the last-mile problem and promote low carbon transportation, hundreds of cities around the world have launched bike-sharing services. A growing number of studies have been mining bike-sharing data from different cities to understand bike-sharing systems. However, there is still a lack of comprehensive understanding of a bike-sharing network structure. Thus, this paper attempts to use complex network theory and spatial autocorrelation analysis approaches to examine structural properties of bike-sharing systems, quantify the importance of bike stations in the network, and evaluate their spatial clustering patterns. This research analyzes bike-sharing trip data from five different sized bike-sharing systems in the United States, Canada, and China. The results of network analysis reveal that the bike-sharing networks have a small-world property with a small average path length and a high clustering coefficient. Compared with medium-scale networks, the connectivity and accessibility of bike stations are relatively low in the large-scale bike-sharing network. Also, the connectivity of bike stations is positively related to their accessibility while they are not highly correlated with their intermediateness. The spatial clustering analysis results indicate that the spatial distributions of connectivity and accessibility of bike stations have a strong global spatial autocorrelation. Also, the stations with high connectivity and accessibility are concentrated in the urban centers, and the stations with low connectivity and accessibility are clustered in the periphery of the urban areas. However, their intermediateness does not show a strong global spatial clustering pattern, which implies that bike-sharing networks consist of multiple sub-groups. The findings provide new insights for transport planners and managers to understand bike-sharing systems and to improve their service quality.

Beam divergence and operating wavelength bands effects on free space optics communication channels in local access networks

Abstract The paper outlines the divergence of beam and operating wavelength bands effects on free-space optics communication channels in local access networks. The max Q factor and min bit error rate are measured based on the divergence of beam and operating wavelength bands variations. The signal is tested also at the receiver side by using an optical power meter visualizer at various operating signal wavelength bands and under the optimum values of the divergence of the beam. The study has presented the optimum operating conditions for upgrading network operation efficiency.

Modular transit: Using autonomy and modularity to improve performance in public transportation

In this paper we investigate a new form of automated public transportation, named ‘modular transit’, configured to overcome the shortcomings of the traditional bus, including the first- and last-mile problem, low occupancy, and low levels of comfort, accessibility, and flexibility. The modular transit system consists of a set of trailer modules who can travel locally to serve demand and connect travelers to main modules for long-distance trips. We mathematically model this system on a time-expanded network, thereby reducing the size of the optimization problem and rendering the problem amenable to being solved with commercial optimization engines. We conduct extensive numerical experiments and sensitivity analyses to study the performance of modular buses under various configurations. Finally, we compare the modular transit service with a door-to-door shuttle service as benchmark to showcase the benefits of modular transit.

A content analysis of transportation planning documents in Toronto and Montreal

In a well-designed public transportation system, planners aim for service to be frequent, fast and cost-effective. The absence of connectivity in a transit system results in public transportation becoming the least appealing mode of choice. This research focused on the last-mile problem (LMP) and its existing interventions in two Canadian cities. It explored the framework employed and language used within transportation planning documents in order to address the last-mile problem (LMP). Through a two-pronged content analysis method, 10 planning documents from Toronto and Montreal were examined to identify ways in which the last-mile problem is engaged and what kind of strategies are provided to address the issue. The manifest content analysis revealed that only two planning documents directly address the last-mile problem. However, the latent content analysis demonstrated ways in which the rest of the key-terms were utilized to further engage with the LMP, resulting in three recurring themes. Several policy recommendations expand on the three themes extracted from the content analysis with emphasis on shared-mobility, public-private partnerships and diversifying land-use as last-mile strategies.

Mikromobilność w systemie transportowym miasta

Mikromobilność to wykorzystywanie w systemie transportowym miast małych i lekkich środków transportu umożliwiających pokonywanie krótkich dystansów. Dzięki niewielkim gabarytom i małej masie ułatwiają one poruszanie się po wąskich i zatłoczonych odcinkach miast, a ich alternatywny napęd eliminuje hałas i redukuje tzw. ślad węglowy. Do środków tych zaliczają się m.in. rowery, hulajnogi, deskorolki, skutery, motorowery, a także małe, lekkie samochody (ang. microcar, quadricycle). Celem artykułu jest wyjaśnienie, czym jest mikromobilność, wskazanie jej miejsca i zastosowania w systemie transportowym miasta oraz zaprezentowanie stanu mikromobilności w Polsce. W realizacji tego celu przydatne były: analiza wybranej literatury przedmiotu i próbne badania z wykorzystaniem kwestionariusza ankietowego. W podsumowaniu zwrócono uwagę na duże zainteresowanie mikromobilnością i jej wpływem na obsługę pierwszego i ostatniego kilometra transportu w mieście, a także na liczne bariery związane z jej wdrażaniem. Zdaniem autora artykułu w postępie mikromobilności bardzo istotnymi zagadnieniami są rozbudowa tzw. niezmotoryzowanej infrastruktury, poszerzenie dostępności do niej, uzupełnianie, modyfikowanie i szybkie przyjmowanie stosownych uregulowań prawnych, opracowanie standardów bezpieczeństwa, homologowanie urządzeń mikromobilności oraz kontrolowanie i nadzór nad tymi urządzeniami w ruchu.

Built environment effects on the integration of dockless bike-sharing and the metro

Bike-sharing provides a convenient feeder mode for connecting to a metro and is believed to be an efficient way to solve the first- and last-mile problem. Despite the increasing attention paid on the use of bike-sharing, few studies have investigated how built environment factors affect the integrated use of dockless bike-sharing (DBS) and the metro. Using data from one of the largest DBS operators in China (Ofo), this paper employed a series of negative binomial regressions to examine the effect of the built environment on the integrated use of DBS and the metro, using Shenzhen as a case study. The findings show that mixed land use is positively related to integrated use. Residential areas have higher access-integrated rates during the morning peak hours, while industrial areas are associated with more integrated uses, connecting factories and metro stations. Furthermore, parks and public squares encourage both access- and egress-integrated use during peak times. Transportation facility features, including bus stops and dedicated bike lanes, are positively related to integrated use, while areas with dense metro distribution and main streets with many intersections are negatively related. Transfer distance also plays a crucial and negative role in integrated use. In addition, metro stations that are closer to the city center with a higher number of passengers are more likely to be integrated with bike-sharing. These findings can be used to collectively facilitate a connection between cycling and metro transit by creating a bicycle-friendly environment.

Examining the prospects for Gigabit Broadband: Lessons learned from Google Fiber

This study examines possible lessons learned from the deployment of residential Gigabit networks based upon the novel approach taken by the Google Fiber project started in 2010. Even though Google Fiber paused any project expansion in 2016, calling into question the viability of their business model, the approach taken by Google Fiber elicits further research interest given four major innovations that this analysis identifies in its fiber-to-the-home business model. Based on a “top-down” financial model to estimate the costs of fiber deployment, this analysis shows that these four innovations pursued by Google Fiber, and now adopted on a widespread basis by other broadband providers, lower the costs of building residential Gigabit networks, and therefore can improve the prospects for new entry of service providers of residential broadband services. With technology advances pointing to further cost reductions in the cost of Gigabit networks, this analysis elevates the need for more detailed study of ongoing changes in the cost structure of local access networks to better anticipate future prospects for broadband competition.

Optimal Location Analysis of Delivery Parcel-Pickup Points Using AHP and Network Huff Model: A Case Study of Shiweitang Sub-District in Guangzhou City, China

The use of parcel-pickup points (PPPs) is an effective approach for solving the last-mile problem. However, few studies provide specific guidance for the optimal organization of PPPs. Here, a geographic information system(GIS)-based hybrid model was developed combining the widely used analytic hierarchy process (AHP) multi-criteria analysis method with the Huff model that predicts the number of visiting customers to determine the optimal facility for collaboration and service as a PPP. Using this model, a decision-maker can select the highest-ranking facility or use the fluctuation ranking graph to determine a priority list of candidate facilities according to the appropriate PPP service distance. Our findings suggest that the optimal candidate facility should be located near high population density areas, a dense road network, and few geographic barriers. The facility should have a high attractiveness value, long business hours, and convenient access to public transportation, cover a large, high-population area, and should be a retail chain store. Based on these findings, the AHP method can improve the accuracy of obtaining the facility attractiveness value using the Huff model. Facility attractiveness has a strong effect on the resulting number of customers in the case of acceptably long distances to residential buildings.

Strategy for the South-South cooperation on schistosomiasis control under the Belt and Road Initiative

Following the concerted efforts for nearly 70 years, great successes have been achieved in the national schistosomiasis control programme in China. Currently, the national schistosomiasis control programme in China is facing the challenges to solve the problems during the"final mile"stage towards schistosomiasis elimination, and contribute Chinese experiences, Chinese strategy and Chinese wisdom to the global schistosomiasis control programmes, so as to facilitate the transformation of the joint efforts in the Belt and Road Initiative to a high-quality development, thereby well supporting the activities on global health security. This paper analyzes the current global status of schistosomiasis and the challenges of the global schistosomiasis control programmes, describes the basis for the cooperation on schistosomiasis control among the countries along the Belt and Road Initiative, illustrates the challenges for translation of Chinese experiences and techniques in schistosomiasis control to other diseaseendemic countries, and proposes the patterns and prospects of the South-South cooperation on schistosomiasis control under the Belt and Road Initiative.

Overclaimed Refunds, Undeclared Sales, and Invoice Mills: Nature and Extent of Noncompliance in a Value-Added Tax

I leverage a Pakistani tax reform that cuts the tax rate on the supply chains of five major industries of the country from 15% to 0% to cast light on the extent of, and mechanisms driving, VAT noncompliance in a representative emerging economy. I find that firms overclaim refunds by 22% and underreport domestic B2C sales by 43.5%. Together, this implies an evasion rate of 77% in the treated industries and 38% in the population. I explore the role of three mechanisms (1) the destination principle, (2) the last-mile problem, and (3) invoice mills in driving this noncompliance.

Overclaimed Refunds, Undeclared Sales, and Invoice Mills: Nature and Extent of Noncompliance in a Value-Added Tax

I leverage a Pakistani tax reform that cuts the tax rate on the supply chains of five major industries of the country from 15% to 0% to cast light on the extent of, and mechanisms driving, VAT noncompliance in a representative emerging economy. I find that firms overclaim refunds by 22% and underreport domestic B2C sales by 43.5%. Together, this implies an evasion rate of 77% in the treated industries and 38% in the population. I explore the role of three mechanisms (1) the destination principle, (2) the last-mile problem, and (3) invoice mills in driving this noncompliance.

Face-to-Face EML Transceiver Tandem for Full-Duplex Analogue Radio-over-Air

An analogue coherent-optical free-space link for local cloud-based radio access networks is proposed and experimentally demonstrated. The adoption of a single externally modulated laser as optical transmitter and coherent homodyne receiver at either link end guarantees conceptual simplicity for the opto-electronic sub-systems of this optical fronthaul. The realization of full-duplex signal transmission over a single, laser-based transceiver device further allows to off-load the directional split in the optically fronthauled radio signal chain to the radio-frequency domain. We prove this concept for an in-door link and show that bidirectional transmission of orthogonally frequency division multiplexed radio signals with 64-point quadrature amplitude modulated formats is possible over an optical budget of 21.3 dB, or over an estimated reach of ∼100 m in case of bad atmospheric conditions. A small penalty of less than 1% in terms of error vector magnitude compared to a direct-detection receiver confirms the correct operation of the low-complexity coherent homodyne detector, even though no digital signal processing functions are applied for the purpose of signal recovery. Continuous long-term measurements including Ethernet payloads confirm the stability of the free-space optical link architecture, for which a small fraction of less than 1% has shown an excursion in reception penalty.

Analysis of multi-modal commute behavior with feeding and competing ridesplitting services

Public transit is an essential travel mode in many urban areas. Emerging dynamic ridesplitting programs provided by transportation network companies (TNCs) can be a double-edged sword to public transit. On the one hand, the program provides convenient services to solve first- and last-mile problems. On the other hand, long-distance ridesplitting services may also draw passengers away from public transit. In this paper, we propose a network model to analyze multi-modal commute behavior with ridesplitting programs as both feeders and competitors to public transit, which is with limited accessibility to passengers. The ridesplitting priority and ridesplitting fare ratio (i.e., ridesplitting fare over non-ridesplitting fare) are incorporated as operational strategies of the TNC. Through numerical studies, we find that a significant number of public transit passengers will shift to long-distance ridesplitting services under low fare ratios; and a high ridesplitting priority can lead to a demand drawback for long-distance ridesplitting, which raises public transit ridership. To maintain public transit ridership, the TNC needs to keep a high fare ratio and a high priority; meanwhile, the number of short-distance ridesplitting orders can also decrease dramatically, which may lead to a loss in unit time revenue of the TNC. We note that a win–win condition can be reached through a separated discount strategy for first- and last-mile ridesplitting services. Such a strategy can both increase the number of short-distance ridesplitting orders for the TNC and boost transit ridership for the government, as well as provide low-cost services to passengers.

A Robot with Decoupled Mechanical Structure and Adapted State Machine Control for Both Ground and Staircase Situations

The rapid development of e-commerce makes the last-mile problem more and more prominent. To meet the requirements of such a scenario, this paper proposes a robot with a decoupled mechanical structure. Such a hexapod robot is divided into a chassis frame with a pair of auxiliary wheel-legs for horizontal movement, a tetrapod for vertical movement, and a slide-and-rail mechanism to connect the former two parts. Such a structure is simple and, thus, cost-efficient; by managing the horizontal and vertical movements, such a robot can keep the balance and safety of the load in the various operation environments, such as roads, staircases, and even indoor ones. Meanwhile, a state-machine-based controller, which adapts well to the unique structure of the proposed robot, is also proposed, simplifying the sequential control of the robot. A prototype robot with 30-kg load ability was built, and the experimental results prove the validity of the design.

Second Opinion: Supporting Last-Mile Person Identification with Crowdsourcing and Face Recognition

As AI-based face recognition technologies are increasingly adopted for high-stakes applications like locating suspected criminals, public concerns about the accuracy of these technologies have grown as well. These technologies often present a human expert with a shortlist of high-confidence candidate faces from which the expert must select correct match(es) while avoiding false positives, which we term the “last-mile problem.” We propose Second Opinion, a web-based software tool that employs a novel crowdsourcing workflow inspired by cognitive psychology, seed-gather-analyze, to assist experts in solving the last-mile problem. We evaluated Second Opinion with a mixed-methods lab study involving 10 experts and 300 crowd workers who collaborate to identify people in historical photos. We found that crowds can eliminate 75% of false positives from the highest-confidence candidates suggested by face recognition, and that experts were enthusiastic about using Second Opinion in their work. We also discuss broader implications for crowd–AI interaction and crowdsourced person identification.

The optimization of leased line distribution at the EDGE of local access network via WAN convergence network

Managing the multiple services of the leased line at the same location is quite critical especially when the resource become highly utilized. Bundling the several network resource components into a one box by simplifying the multiple networks to a single network can help to reduce the utilization of network resources. This paper presents a study on optimiziation of leased line distribution at the EDGE of Local Access Network via WAN convergence network. In this study, a WAN Convergence Network is designed which intends to use only a single leased line network in a location rather than multiple leased lines. It is using a simple concept of SDH structured which channelized the time slots and control the transmission line. The time slots will be relocated from the multiple leased lines into a WAN Convergence Network and it will be de-multiplexed through the Data Circuit Terminating Equipment (DCE) at the customer premises. The WAN Convergence Network design starts from the Digital Data Network (DDN) until the DCE which includes the Local Access Network. This approach will be able to save the network resource especially the time slots, cable port, DCE and consequently avoid adding new network infrastructure. This research will result to the new network design which offer multiple leased line networks at the customer end by using only one dedicated leased line network namely WAN Convergence Network.

Solving the first‐mile ridesharing problem using autonomous vehicles

AbstractAutonomous vehicles (AVs) are paving a way to reshape the operation and management of urban transportation systems by improving travel mobility. In this study, we propose to use AVs for solving the first‐mile (FM) problem that aims to transport passengers from their homes to metro stations. Passengers submit travel requests in advance and a fleet operator dispatches AVs and arranges ridesharing in a rolling horizon framework. The ridesharing is implemented by assigning one AV to serve several requests subject to the vehicle capacity, the maximum travel time, and the accessibility constraints. A mixed integer linear programming (MILP) model is formulated to determine the AV dispatch and ridesharing schemes for the minimum operational costs. Then, another MILP model with the objective of the maximum user satisfaction is formulated for the purpose of comparison. A cluster‐based solution method is designed to deal with the large‐scale FM problem. Extensive numerical experiments are conducted to demonstrate the application of the proposed method. Results show that ridesharing can reduce both required AV fleet size and vehicle traveled miles. The proposed solution method is able to solve the problem efficiently and fulfil the requirement of online computation.

Segmenting the public’s risk beliefs about drone delivery: A belief system approach

Risk beliefs inherently impinge on the rapid proliferation of drone delivery, which provides a promising solution to the last-mile problem. Communication campaigns that seek to inspire the public’s uptake of the innovative technology are challenging because the risk beliefs vary across different segments in a larger population. While previous segmentation efforts rely on theoretically distal causes of behavior such as demographics and personality traits, the study was the first to explore audience subgroups based on implications of the structural interconnections of risk beliefs in a cognitive system. Using the data from a national survey, this study conducted a latent class analysis and identified four distinct profiles of U.S. urban residents’ (N = 474) risk beliefs about drone delivery. Drawing from research on belief formation and change, the study further found that attitudes toward drone delivery, perceived innovativeness of an organization due to drone adoptions, and expectancy predicted the audience profiles, but perceived behavioral control did not. The findings highlight the insights from a belief-system approach to audience segmentation and provide an empirical basis for targeting groups of the audience with the right communication strategies to inspire adoption of the innovative technology.