bluuebunny/crossref_metadata_2025 huggingface dataset:
Voltaire on Mazepa and Early Eighteenth-Century Ukraine
Authors: Prymak Thomas M .
Published: December 2016

This study offers a comparison of Voltaire’s treatments of Ivan Mazepa and his Ukrainian Cossack homeland in two of his best known historical works: his History of Charles XII, King of Sweden and his History of the Russian Empire under Peter the Great. It also discusses Voltaire's use of written and oral sources and his historical method in general. Voltaire's attitude towards the Ukrainian rebel Hetman or ruler, Mazepa, and Ukrainian independence in general, was basically positive in his earlier work on Charles, but was much more guarded, indeed negative, in his History of the Russian Empire, which was a work commissioned by the Russian court that greatly praised the reforms of the iron-willed Tsar. However, in extensive revisions of his book on Charles, done simultaneously with his work on Russia, Voltaire did not change his generally positive view of Mazepa and Ukrainian independence, and so, his true attitude remains somewhat difficult to determine. Voltaire's work on Charles in particular was very influential throughout Europe during the Romantic period and was the ultimate source of Byron's poem on Mazepa, and after him, many other works of literature, painting and music that treated the Mazepa theme.
June 1940: The Italian Army and the Battle of the Alps
Authors: Sica Emanuele
Published: December 2016

This article focuses on the Battle of the Alps of June 1940, which pitted the Italian Regio Esercito against the French Armée des Alpes. Fearing that an early capitulation of France to the German invasion that had begun in May would prevent Italy from sharing the spoils of victory, Mussolini ordered an offensive against France on 15 June 1940. Despite the battle raging in the north, the French Army successfully repelled the attacking force and the Italian assault petered out after a few days, with no significant victories and few territorial gains. Aside from the difficulties of crossing the Alpine mountain range, a geographical feature the French had strongly fortified, the Italian campaign was hindered by poor strategy, ineffective tactics, an outdated military doctrine that failed to acknowledge the importance of combined arms warfare, and appallingly inadequate materiel owing to the erosion of the Italian military industrial base in the 1930s. In fact, the Battle of the Alps set the tone for the overall disappointing military campaign of the Regio Esercito in the Second World War, as the Italian army never fully recovered from its dismal start.
The Quest for Acceptability: The Socialists’ May Days in Bavaria and Brittany, 1920-40
Authors: Bargain-Villéger Alban
Published: December 2016

This article explores the ways in which French and German Socialists incorporated May Day in their communication strategies in the 1920s and 1930s. Focusing on two of the most important socialist parties of the interwar period, the SFIO (French Section of the Workers’ International) and the SPD (Social Democratic Party of Germany) in two particularly conservative regions, Brittany and Bavaria, this article demonstrates the importance of syncretism—defined as the blending of the traditional with the new—as a propaganda tool in hostile political environments. It argues that May Day press campaigns contributed to portraying the SFIO and the SPD as comprehensive republican parties, and that the similarities between their uses of syncretism show that the two parties have had more in common than has previously been assumed.
Evaluating Off-Peak Pricing Strategies in Public Transportation with an Activity-Based Approach
Authors: Lovrić Milan , Raveau Sebastián , Adnan Muhammad , Pereira Francisco C. , Basak Kakali , Loganathan Harish , Ben-Akiva Moshe
Published: December 2016

Public transportation authorities across the world are implementing various peak and off-peak pricing strategies to manage travel demand and improve the overall system performance. In this study, an activity-based demand framework was used to evaluate two off-peak pricing strategies currently in use in Singapore. These strategies consisted of a free prepeak travel on mass rapid transit (MRT) and an off-peak discount for an integrated transit (public buses and MRT). Smart card data collected before and after the implementation of the first policy were used to calibrate the behavioral models involved, to capture travelers’ preferences and choices properly. To evaluate both pricing strategies, a comprehensive set of key performance indicators was considered and included the changes in peak ridership, average trip fare, operator’s revenue, the number of public transportation trips, and mode share. The results indicate that off-peak discount pricing strategies are a viable policy option for spreading demand peaks and that they are more effective during the afternoon peak period. This study also demonstrates the capabilities and the advantages of an agent-based modeling platform, SimMobility, as a tool for policy analysis.
Social and Distributional Effects of Public Transport Fares and Subsidy Policies: Case of Madrid, Spain
Authors: Cadena Paola Carolina Bueno , Vassallo Jose Manuel , Herraiz Israel , Loro Manuel
Published: December 2016

Despite the widespread implementation of urban transport subsidies in many cities, there are still only a limited evaluation of the equity of these policies and scarce quantitative assessment of their distributional incidence. This research contributes to filling this gap by developing a practical approach to evaluate the impact of fare subsidization on vertical equity. This paper implements a two-step methodology. First, two main indicators were developed to measure the social impact of the travel pass, a highly subsidized fare, to determine the effectiveness of the policy in reaching lower-income citizens. Second, by using the latest disaggregated data from a transportation survey, in Madrid, Spain, a multiple regression model revealed that travel pass usage (TPU) depended mainly on income level and accessibility to public transport. The results show that the accessibility level has a positive effect on the TPU indicator, whereas income level has a negative influence. Because income level is shown to play the most significant role in influencing public transport use, the subsidy policy associated with the travel pass in the city can be considered progressive, since it effectively targets economically disadvantaged groups. This fact suggests that subsidies for public transport in Madrid tend to favor vertical equity.
Predicting Express Train Choice of Metro Passengers from Smart Card Data
Authors: Kim Kyung Min , Hong Sung-Pil , Ko Suk-Joon , Min Jae Hong
Published: December 2016

This paper addresses the problem of predicting the express local train choices of metro passengers. The model was built and tested on the preferences observed from smart card data. The revealed preference data, because of intensiveness, can also accurately capture the marginal effects of the core attributes, in-vehicle time and wait time, on the express train choices by metro passengers. To be specific, the marginal disutility of a path decreases in in-vehicle time and increases in wait time. Accordingly, this paper employs a Box–Cox transform to adjust the constant marginality of a linear model to the nonconstant marginal disutility. The resulting nonlinear logit model improved the predictability of a conventional linear model. Tested on the Incheon–Yongsan interval of the Gyeong-In Line of the Seoul metropolitan area in South Korea, the model predicted a correct choice by a passenger in 99.9% and 99.5% of the cases during peak and nonpeak hour periods, respectively, compared with 96.9% and 95.8%, respectively, from a linear model. The model, applied to Line 9 without a parameter tuning, achieved a predictability greater than 95%.
Bus Network Microsimulation with General Transit Feed Specification and Tap-in-Only Smart Card Data
Authors: Gaudette Philippe , Chapleau Robert , Spurr Tim
Published: December 2016

Simulation models are vital instruments for properly evaluating proposed interventions on the public transport network. Because of data constraints, traditional planning models have been based on simplified representations of supply and demand. The goal of this paper is to demonstrate the feasibility of constructing a highly detailed public transit microsimulation model using general transit feed specification (GTFS) (complete planned service in the form of schedules transmitted to the public) and smart card data collected from a surface bus network. Since the validation protocol is tap-in only and the validation equipment by default provides no location information, algorithms are developed to derive boarding and alighting locations by using the recorded times of the fare validations. The GTFS schedule data are transformed into network format. The smart card data and GTFS data generate, respectively, highly detailed representations of transit demand and supply that are ideally suited for analysis using a powerful microsimulation tool (in this case, TRANSIMS). The results of these procedures demonstrate the feasibility of using smart card data and GTFS data as the basis for simulation of a surface transit network and offer the potential to dramatically increase the precision and versatility of public transport planning.
How Smart Is Your Smart Card?: Evaluating Transit Smart Card Data with Privacy Restrictions and Limited Penetration Rates
Authors: Erhardt Gregory D.
Published: December 2016

Transit smart card data can be analyzed for a number of planning applications, but not all smart card systems produce data of similarly high quality. The primary objective of this research is to evaluate the usefulness and validity of smart card data that are constrained by strong privacy protections and a limited penetration rate. In addition, a method is proposed to mitigate the biases inherent in the data. This analysis, done for the Clipper Card system in the San Francisco Bay Area of California, provides evidence for other agencies seeking to understand the value and limitations of their own data. The evaluation finds that the major limitation of the data is that a combination of the card technology, data coding, and privacy restrictions prevents the transaction location from being identified when the tag-on occurs on a vehicle instead of at a station. Several biases are identified in the users of Clipper Cards in terms of when the data are compared with external data sources, including automated passenger counters and onboard survey data. The onboard survey data are used to estimate a discrete choice model of Clipper Card use. The reciprocal of the modeled probability of using a Clipper Card is proposed as a correction factor. The proposed correction factor is found to mitigate, but not to eliminate fully, the biases in Clipper use. In spite of these limitations, the data are found to be valuable for certain applications, such as identifying transfers. Recommendations are provided for how the data can be improved.
Perspectives on Transit: Potential Benefits of Visualizing Transit Data
Authors: Stewart Colin , Diab Ehab , Bertini Robert , El-Geneidy Ahmed
Published: December 2016

Advancements in information and communication technologies have enabled transit agencies around the world to generate streams of data on a high-frequency basis. Increasingly, these agencies are interested in new methods of visualizing these data to communicate the results of their planning efforts, operational investments, and overall transit performance to decision makers and stakeholders. Most agencies today collect and provide numerous kinds of data, including Google’s general transit feed specification schedule data, automatic vehicle location data, and automatic passenger count data. This paper aims to demonstrate the untapped potential of these data sources; specifically, the paper uses transit data from Montreal, Quebec, Canada, to generate performance measures that are of interest to both transit planners and marketing professionals. Some of these measures can also help in communicating the positive attributes of public transportation to the community. Performance measures are generated at different scales, including transit system, neighborhood, route, and stop levels. This paper expands on previous research on transit performance research and visualization by adopting currently available resources for so-called big data.
Analysis of Grid Cell–Based Taxi Ridership with Large-Scale GPS Data
Authors: Nam Daisik , Hyun Kyung (Kate) , Kim Hyunmyung , Ahn Kijung , Jayakrishnan R.
Published: December 2016

Understanding the spatial variation of taxi ridership is of critical importance to many government agencies and taxi companies because taxis’ location dependency on spatial pattern of passenger demand results in spatially unbalanced taxi demand and supply. This study presents an analysis of the spatial distribution of taxi ridership by using large-scale GPS taxi trip data collected from Seoul, South Korea. To capture the spatial variations better in taxi ridership, GPS entities were disaggregated into units of a uniform size with a grid cell decomposition method. A geographically weighted spatial regression was applied to model spatial correlations of factors associated with transit and urban density to taxi ridership. Results from the proposed method demonstrated a higher relationship between taxi and subway ridership in the regions where lower accessibility to subway stations existed. In these regions, taxis were found to perform as a complementary mode to subway. In residential and commercial districts, this analysis showed that population and employment were highly related to taxi ridership. In contrast, in central business districts it was the building area (floor space), rather than population and employment, that was highly related to taxi ridership.
Toward a Demand Estimation Model Based on Automated Vehicle Location
Authors: Moreira-Matias Luis , Cats Oded
Published: December 2016

The rapid increase in automated data collection in the public transport industry facilitates the adjustment of operational planning and real-time operations based on the prevailing traffic and demand conditions. In contrast to automated passenger counts systems, automated vehiclve location (AVL) data are often available for the entire public transport fleet for monitoring purposes. However, the potential value of AVL data in estimating passenger volumes has been overlooked. This study examined whether AVL data could be used as a stand-alone source for estimating onboard bus loads. The modeling approach infers maximum passenger load stop from the timetable and then constructs the load profile by reverse engineering through a local constrained regression of dwell times as a function of passengers flows. To test and demonstrate the potential value of the proposed method, a proof of concept was performed by conducting unsupervised experiments on 1 month of AVL data collected from two bus lines in Dublin, Ireland. The results suggest that this method can potentially estimate passenger loads in real time in the absence of their direct measurement and can easily be introduced by public transport operators.
Asset-Lite Parking: Big Data Analytics in Development of Sustainable Smart Parking Solutions in Washington, D.C.
Authors: Dey Soumya S. , Darst Matt , Dock Stephanie , Pochowski Alek , Sanchez Eduardo Cardenas
Published: December 2016

Real-time parking occupancy detection is often the missing piece when municipalities migrate up the smart parking spectrum. Municipalities use occupancy detection to ( a) provide real-time information to customers about parking availability; ( b) make demand-based price adjustments for the efficient use of curb space in a congested area; ( c) establish the right meter policies, such as time limits; and ( d) inform parking enforcement. The state of the practice for occupancy detection has been the use of assets (e.g., sensors and cameras) for every parking space. However, given current pricing models and usage patterns, this approach is neither economically sustainable nor necessary. The ParkDC Penn Quarter–Chinatown pilot launched in Washington, D.C., seeks to develop reliable occupancy data on the basis of information from all parts of the parking ecosystem (e.g., networked meters, enforcement, and pay-by-cell transactions). Combined with a sampling of occupancy data collected through limited sensor deployment, mobile cameras, and fixed cameras, Washington, D.C., aims to develop a sustainable solution based on an optimal mix of assets and coverage. The cost, customer satisfaction, revenue, and operational implications of asset-lite solutions are discussed. This paper will enable jurisdictions to develop cost-efficient models for occupancy detection so that those jurisdictions can strategically position themselves to implement real-time availability information and performance-based pricing.
Operational Concepts for Truck Maneuvers with Cooperative Adaptive Cruise Control
Authors: Nowakowski Christopher , Thompson Deborah , Shladover Steven E. , Kailas Aravind , Lu Xiao-Yun
Published: December 2016

Cooperative adaptive cruise control (CACC) has been loosely defined in recent literature to represent a wide variety of vehicle-following control concepts, and when trucks are discussed, CACC is often used synonymously with platooning. This paper discusses the similarities and differences between CACC and platooning and provides a more precise functional description of CACC operations for trucks. CACC operations include not only the steady state cruising mode but also the maneuvers needed to join vehicles together and separate them when a vehicle needs to leave a CACC string or when the string is interrupted by a cut-in maneuver by a noncooperative vehicle. Activity diagrams are used to describe the CACC maneuvers; the diagrams specify the sequence of actions that need to be taken by each driver and each vehicle (and its CACC software) and the information that needs to be exchanged between them. These precise definitions can be used to specify the vehicle-to-vehicle messages that need to be exchanged between vehicles to implement CACC and the driver–vehicle interface displays and controls that are needed. The paper also addresses practical considerations in CACC operation, such as maximum lengths for strings of CACC trucks, strategies for sequencing the trucks in CACC strings, and higher-level strategies for clustering CACC-capable trucks; these strategies range from ad hoc to local and global coordination.
Use of Speed Measurements for Highway Traffic State Estimation: Case Studies on NGSIM Data and Highway A20, Netherlands
Authors: Roncoli Claudio , Bekiaris-Liberis Nikolaos , Papageorgiou Markos
Published: December 2016

This paper presents two case studies in which a macroscopic model-based approach for the estimation of traffic conditions, which the authors have recently developed, is employed and tested. The estimation method is developed for a mixed traffic scenario, in which traffic is composed of both ordinary and connected vehicles. Only average speed measurements, which may be obtained from connected vehicle reports, and a minimal number (sufficient to guarantee observability) of spot sensor–based total flow measurements are utilized. In the first case study, NGSIM microscopic data are used to test the capability of estimating traffic conditions on the basis of aggregated information retrieved from moving vehicles and considering various penetration rates of connected vehicles. In the second case study, a longer highway stretch with internal congestion is utilized to test the capability of the proposed estimation scheme to produce appropriate estimates for varying traffic conditions on long stretches. In both cases, the performances are satisfactory and the obtained results demonstrate the effectiveness of the method in both qualitative and quantitative terms.
Information Age in Forward Collision Warning Based on Vehicle-to-Vehicle Communications: Sensitivity Analysis
Authors: Hsu Chung-Jen
Published: December 2016

Connected vehicles transmit and receive basic safety messages that enable the use of safety applications intended to avoid crashes. The information age (IA) is the latency between the basic safety message being generated by the transmitting vehicle and received by another vehicle. The receiving vehicle’s processing time is included in the IA but, at several milliseconds, can be ignored. The IA of vehicle-to-vehicle communications needs to be kept beneath a certain threshold so as not to compromise the effectiveness of safety applications. Forward collision warning (FCW) requires a critical IA in scenarios in which a lead vehicle brakes hard and abruptly. An analytical model of FCW, with the lead vehicle coming to a complete stop, is proposed. For the host vehicle behind the lead vehicle to stop safely, an appropriate IA, perception–reaction time, and deceleration rate are required. Sensitivity analysis of the IA is performed to provide the probabilities of a safe stop for various combinations of speed and deceleration rate. Monte Carlo simulations are implemented to generate the probabilities, and perception–reaction times, speeds, and deceleration rates are formulated as probability density functions. The results show that the IA is a sensitive factor in the safe operation of an FCW application. The IA for a low-speed host vehicle is more sensitive than the IA for a high-speed host, when the host and lead vehicles are both traveling at similar speeds with a normal clearance gap. The IA is more sensitive when the host vehicle speed is low (≤40 mph) or when the lead vehicle’s deceleration rate is high (≥0.5 g).
Challenges in Applying Calibration Methods to Stochastic Traffic Models
Authors: Wagner Peter , Buisson Christine , Nippold Ronald
Published: December 2016

This paper evaluates calibration and validation as a means to understand traffic flow models better. The paper concentrates on the car-following part of these models and demonstrates that the calibration of stochastic models under certain circumstances can become difficult. Three types of stochasticity are distinguished for microscopic traffic flow models: the stochasticity coming from noisy data, the stochasticity coming from the distribution of the parameters describing the driver’s behavior, and the stochasticity coming from the model itself when a noise component is added to a deterministic differential equation governing the vehicle’s movements. By using four submodels with four noise terms and an identical deterministic part, this paper shows that a calibration with synthetic and, therefore, reproducible data can lead to results that are awry. The parameters fitted by the calibration procedure were significantly different for the deterministic and stochastic models. It was concluded that stochasticity was the reason why the parameter estimation of stochastic models sometimes failed. Up to now, the authors have not been able to propose a solution to cope with this intrinsic pitfall of genuine stochastic models.
Data Assimilation Using a Mesoscopic Lighthill–Whitham–Richards Model and Loop Detector Data: Methodology and Large-Scale Network Application
Authors: Duret Aurélien , Leclercq Ludovic , El Faouzi Nour-Eddin
Published: December 2016

Traffic managers and operators need decision support systems able to provide online traffic flow monitoring and short-term traffic predictions on large-scale networks. Data assimilation (DA) techniques are used to combine observed data and a traffic model. This paper proposes a comprehensive data assimilation framework, based on a mesoscopic Lighthill–Whitham–Richards model, that has short computational times, is well suited for network discontinuities, provides individual vehicle tracking, and can easily be coupled with any dynamic traffic assignment model. The framework also relies on state variables that require adjustments of the DA framework. The requirements proposed by the paper are concerned with ( a) the model numerical scheme, ( b) the traffic state transformation operators, and ( c) updating of the model. The proposed DA framework is first applied to a simplified network. It validates the ability of the proposed framework to update and propagate traffic states accordingly. The proposed framework is then applied to a real large-scale network. The results demonstrate its ability to monitor and forecast traffic conditions with online capabilities.
Exploratory Analysis of Signal Coordination Impacts on Macroscopic Fundamental Diagram
Authors: Girault Jan-Torben , Gayah Vikash V. , Guler Ilgin , Menendez Monica
Published: December 2016

The macroscopic fundamental diagram (MFD) of urban traffic is a recently developed tool to describe traffic on large-scale urban networks. A network’s MFD can be significantly affected by various properties, including signal settings, block lengths, travel speeds, and routing behaviors. However, current understanding of the impact of signal offsets (i.e., signal coordination) on the MFD is limited to idealized one-dimensional networks, and little is known about how signal coordination affects the MFDs of more realistic two-dimensional networks. To overcome this gap, the present study examined the impacts of signal coordination on the MFD of an idealized two-dimensional grid network using both an analytical method and a microscopic traffic simulator (Aimsun). Seven coordination strategies were considered, including the simultaneous, alternating, double-alternating, one-dimensional green-wave, two-dimensional green-wave, MAXBAND, and random strategies. In general, the impacts of coordination were highly sensitive to the signal cycle length chosen. The results also revealed that poor coordination can significantly decrease the network capacity and the free-flow travel speed. However, good coordination offers little advantage over simultaneous offsets, even with directional travel demands moving in the prioritized directions. The reason is that the benefits provided to vehicles in the prioritized directions are negated by the disadvantages to vehicles traveling in the nonprioritized directions. These results suggest that the insights from other idealized simulations with simultaneous offsets may be generalizable to more realistic situations with more realistic coordination strategies.
Modeling Driver Behavior in a Connected Environment: Integrated Microscopic Simulation of Traffic and Mobile Wireless Telecommunication Systems
Authors: Talebpour Alireza , Mahmassani Hani S. , Bustamante Fabián E.
Published: December 2016

Connected and autonomous vehicles will influence the future of the surface transportation system by enhancing safety, improving mobility, reducing energy consumption, and controlling emissions. The real-time information provided by connected vehicles technology allows drivers to become more aware of the surrounding traffic conditions and to maneuver safely and more efficiently. Furthermore, when coupled with onboard sensing technologies, the connected vehicles technology can improve the efficiency and the reliability of a driverless transportation network. This paper presents a comprehensive simulation framework to model driver behavior in a connected driving environment with connected vehicles. The framework, which consists of a microscopic traffic simulator integrated with a discrete-event communications network simulator, Network Simulator 3, forms a basis for exploration of the properties of the resulting traffic systems and assessment of the system-level impacts of these technologies. Furthermore, the connectivity of a vehicle-to-vehicle and vehicle-to-infrastructure communications network was investigated with the FHWA Next Generation Simulation: US-101 Highway data set (to represent vehicular movements in a highway environment). It was found that signal interference can result in information loss and partial connectivity. Finally, through the implementation of a speed harmonization algorithm, the paper discusses the importance of consideration of telecommunications along with vehicular movements to investigate the effects of connected vehicle applications on mobility and emissions.
Effects of Dynamic Speed Limits on a Dutch Freeway
Authors: Plana Joel , Soriguera Francesc , Hegyi Andreas
Published: December 2016

This paper describes the effects of dynamic speed limit (DSL) control on a three-lane section on the A13 Freeway in Rotterdam, Netherlands. The main objective was to contrast the latest empirical findings from an experiment conducted in Barcelona, Spain, in which the main line metering capability (i.e., gating, or main line flow restriction) was questioned because of subcritical speed limits (e.g., speed limits down to 40 km/h). Moreover, according to the results of the study conducted in Barcelona, the validity of the current fundamental diagram models accounting for DSL control could be strongly compromised. This investigation took advantage of the huge amount of empirical traffic data recorded by the Dutch government and of the DSL control strategies present on most freeways in the Netherlands. The data were treated to identify stationary periods of traffic. To this end, a method that was found to be reproducible elsewhere and computerized into an algorithm was developed. The fundamental diagram was used as a graphical tool to assess the results. The main findings do not contradict the observations from the study performed in Barcelona. Flows of 1,850 vehicles per hour per lane were steadily observed at the subcritical speed limit of 50 km/h. The reactive nature of DSL control implemented in the Netherlands implies that very low speed limits do not affect a wide range of traffic states. This finding hampered the possibility to extend this conclusion. Further research with fewer limiting DSL control strategies is necessary to clarify the extent of the phenomenon considered.
New Extended Discrete First-Order Model to Reproduce Propagation of Jam Waves
Authors: Han Yu , Yuan Yufei , Hegyi Andreas , Hoogendoorn Serge P.
Published: December 2016

This paper proposes an extension of the discrete Lighthill–Whitham–Richards model of the cell transmission model type to reproduce capacity drop and the propagation of jam waves. Recent studies have tried to incorporate the capacity drop into discrete first-order traffic flow models for traffic optimization purposes. It was found that the inflow to a discharging cell predicted by these models might have been overestimated, and this overestimation influenced the propagation of a jam wave. An empirical analysis was carried out to confirm this assumption. It was found that the extent of the flow reduction depended on the state difference between the targeting cell and its upstream cell. On the basis of these findings, a new mathematical model formulation is given. Simulations with both a hypothetical freeway stretch and a real-life freeway stretch are performed to test the behavior of the proposed model. The previously mentioned models are also simulated for comparison. The simulation results indicate that the proposed model is better able to reproduce jam waves. In addition, the proposed model can be used in a linear model predictive control framework and formulated as a linear optimization problem, which may be beneficial for a real-life, real-time application.
Resolution of Activity Scheduling Conflicts: Reverse Pairwise Comparison of In-Home and Out-of-Home Activities
Authors: Langerudi Mehran Fasihozaman , Anbarani Ramin Shabanpour , Javanmardi Mahmoud , Mohammadian Abolfazl (Kouros)
Published: December 2016

This paper proposes a new methodology for solving a pairwise comparison problem from a polychotomous classification. The proposed methodology reverses the pairwise coupling and employs the Bradley–Terry formulation for estimating pairwise comparison models. This methodology was implemented through relevant models in Agent-Based Dynamic Activity Planning and Scheduling (ADAPTS) and aims for solving pairwise activity conflicts. At one step of the framework, given the default algorithm, agents have to make a choice between in-home and out-of-home activities. At this time step, the reverse pairwise comparison models are called to investigate the agents’ resources and conditions for making the most probable decision about which activity to engage in. This work was conducted in conjunction with an earlier effort to incorporate in-home activities into ADAPTS, and the models proposed provide a behavioral decision-making process for this purpose.
Can Multimodal Real-Time Information Systems Induce a More Sustainable Mobility?
Authors: Pronello Cristina , Veiga-Simão José , Rappazzo Valentina
Published: December 2016

Interest in advanced traveler information systems (ATIS) is increasing in modern cities, and more attention is given to real-time multimodal information. Through those systems, decision makers hope to achieve a shift from the car to alternative, environmentally friendly modes of travel. Few comprehensive assessments have been undertaken to verify the actual contribution of ATIS to such modal shift. In this paper, the effects on travel behavior of Optimod’Lyon, a multimodal real-time information navigator for the smartphone developed in Lyon, France, in 2013 and launched in May 2015, are assessed. To this end, a mixed method was adopted. A questionnaire was administered and focus groups were organized before and after the test of the application. A stratified sample of 50 people living in the metropolitan area of Lyon was also involved. The theory of planned behavior was used as the framework for the questionnaire design, which investigated attitudes, subjective norms, and perceived behavioral control. To evaluate behavioral change, data were analyzed through the use of parametric and nonparametric tests, factor analysis, and binary logistic regression. Survey participants were initially interested in Optimod’Lyon and showed a positive attitude toward its use. Before the test, they evaluated the travel planner positively but this lessened over time. After the test, use of the various travel modes remained stable. Consistency with regard to the most used mode and to behavioral patterns and attitudes was shown, strongly related to habits and to the frequency of past behavior.
Examination of the Impacts of Telecommuting on the Time Use of Nonmandatory Activities
Authors: Asgari Hamidreza , Jin Xia , Du Yiman
Published: December 2016

How and to what extent telecommuting engagement affects time allocation among nonmandatory activities are examined to help understand the impacts of telecommuting on daily activity–travel patterns. Five categories of nonmandatory activities are considered: shopping, maintenance, discretionary, escort, and in-home shopping. The hypothesis is that telecommuting relaxes the temporal and spatial constraints related to work activities at the regular workplace, and telecommuters may allocate some of the time budget to other nonmandatory activities, which may or may not lead to additional travel. The structural equations model approach is applied to capture the impacts of telecommuting as well as the interactions among the nonmandatory activities. The activity durations by type along with the number of total daily trips are considered as endogenous (dependent) variables. By incorporating work hours at the regular workplace and daily telecommuting hours as exogenous variables, the models can reveal how people may reallocate their time among different nonmandatory activities given different levels of telecommuting engagement (either part-day or full-day). All types of telecommuting arrangements increased nonmandatory activity durations (compared with those of nontelecommuters). Full-day telecommuters have higher durations of discretionary activities, while part-day telecommuters have higher durations of maintenance and out-of-home shopping errands. Telecommuting also increased total daily trip rates for both telecommuters and their household members. This study used data obtained from the 2010–2011 Regional Household Travel Survey in the New York metropolitan region.
Associations Between Online Purchasing and Store Purchasing for Four Types of Products in Nanjing, China
Authors: Zhen Feng , Cao Xinyu (Jason) , Mokhtarian Patricia L. , Xi Guangliang
Published: December 2016

As e-shopping proliferates, transportation planners examine the extent to which it will replace shopping trips. Although previous studies have explored relationships between online purchasing and store purchasing, few have examined the relationships for different types of products in China. A joint ordered probit model was applied to investigate the relationships among 963 respondents in Nanjing, China. Online purchasing had positive associations with store purchasing for all four types of products (clothing, books, daily goods, and electronics), even after shopping attitudes and demographics were controlled for. The magnitude of the complementarity effect differs by product type, with less frequently purchased products showing a larger effect. The impact of online purchasing on road systems is limited in China because transit and walking are dominant modes for shopping trips. However, the impact is expected to grow.
Long-Term Field Transverse Cracking Performance of Warm-Mix Asphalt Pavement and Its Significant Material Property
Authors: Wu Shenghua , Wen Haifang , Zhang Weiguang , Shen Shihui , Faheem Ahmed , Mohammad Louay N.
Published: December 2016

With the growing awareness of sustainable construction practices and because warm-mix asphalt (WMA) is environmentally friendly, WMA is gaining popularity for pavement construction in the United States. Currently, it is generally believed that rutting and moisture damage are two major concerns for WMA pavements, but because WMA requires less aging, its cracking resistance is expected to be improved. One of the primary cracking distresses of concern is transverse cracking, which could be thermal cracking in asphalt pavement or reflective cracking in asphalt overlay caused by underlying thermal cracking. Thus, transverse cracking is another primary distress. This study investigated the long-term field transverse cracking of 28 pavement projects, including WMA pavements and corresponding hot-mix asphalt (HMA) control pavements across the United States, covering different climate zones, WMA technologies, service years, pavement structures, and traffic volume levels. Two distress surveys were conducted at an interval of 2 years, and the material properties of the asphalt mixtures and binders were determined with field cores and extracted binders. The long-term field performance of the WMA and HMA pavements were compared for transverse cracking. The study found that HMA and WMA pavements exhibited comparable transverse cracking. Fracture work density obtained from indirect tensile testing at 14°F was found to be the significant determinant for transverse cracking. Significant mix design parameters were identified that can affect the resistance of mixtures to transverse cracking and that can be employed to guide the development of a well-performing mix design.
Effectiveness of Changes in Street Layout and Design for Reducing Barriers to Walking
Authors: Anciaes Paulo Rui , Jones Peter
Published: December 2016

This study analyzed the effectiveness of two types of interventions to reduce built environment barriers to walking: changing the layout of the local street network (by increasing the density and connectivity of the links available to pedestrians) and redesigning a busy road (by adding crossing facilities, reducing the speed limit, or reallocating road space to pedestrians). The analysis focused on a residential neighborhood in London that was being extensively redeveloped. Anticipated effects of the interventions are assessed in regard to distance, delay, risk, and environmental quality of walking trips from residences to public transport nodes. The study also addressed methodological issues by modeling the off-street space available to pedestrians and considering alternative hypotheses for pedestrian route choice. Results show that, in this neighborhood, changes to the street layout always reduced delay and improved the pedestrian environment, although the changes might have increased trip distances and collision risk. Adding crossing facilities reduced risk but did not decrease delay, while reducing the number of vehicle lanes reduced distance and delay but might increase risk. All types of intervention improved the pedestrian environment, even in the cases of routes chosen to minimize delay or exposure to traffic.
Multiobjective Evaluation of Midblock Crosswalks on Urban Streets Based on TOPSIS and Entropy Methods
Authors: Yang Zhao , Liu Pan , Xu Xin , Xu Chengcheng
Published: December 2016

This study presents a multiobjective evaluation method to estimate the performance of various midblock crosswalk treatments on urban streets. The considered objectives included traffic operation, traffic safety, environmental impacts, and costs. Data were collected at 16 midblock crosswalks in the Nanjing area in China. Vissim simulation models were developed and calibrated with field data to evaluate the operational and environmental impacts of various midblock crosswalk treatments. For the impact of various treatments on traffic operation, the total control delay to vehicles on the major streets and pedestrians were estimated. For the impact on traffic safety, the frequency of traffic conflicts was calculated. For the impact on the environment, vehicle emissions and fuel consumption were quantified. The TOPSIS entropy evaluation method was then used to rank the performance of various treatments of crosswalks considering multiple performance measures. Compared with the life-cycle cost analysis method that quantifies the benefits and costs using monetized expressions to establish a common unit, the TOPSIS method presented does not require the well-developed economic theories of valuation. It was found that by combining multiple objectives in decision making, one may obtain different results with regard to the optimum treatments of crosswalks. The research results can be directly used by traffic engineers to select crosswalk treatments given traffic flow conditions and geometric design characteristics. The framework implemented in the study can also be used to estimate the impacts of other traffic projects considering multiobjective evaluation.
Adaptive Walk Intervals
Authors: Furth Peter G. , Halawani Ahmed T. M.
Published: December 2016

If the vehicular phase concurrent with a pedestrian phase is running under fully actuated control or is a noncoordinated phase under coordinated-actuated control, the length of its green is not known when the phase begins; it could run anywhere between a (known) minimum and maximum green, depending on when a gap is detected. In such a case, walk intervals are generally kept to a minimum length to prevent the pedestrian phase from constraining the ending of green that can lead to situations in which the pedestrian phase has cleared yet the concurrent phase continues its green for 20 more seconds. Proposed is the concept of an adaptive walk interval whose length is based on the predicted length of the concurrent phase’s green, which in turn is calculated cycle by cycle with data from recently past cycles. That way, during heavy traffic periods in which the vehicular phase usually goes well beyond its minimum, a longer-than-minimum walk interval can be provided with very little impact on signal operation or vehicular delay. Two methods, ratio estimation and stratification, are proposed and tested for predicting the green time needed by a vehicular phase; both methods use as data only traffic signal timing data from the last several cycles. Simulation tests with coordinated-actuated and fully actuated control, with and without pedestrian recall, and with and without permissive windows show that adaptive walk intervals can markedly reduce pedestrian delay with almost no impact on vehicular delay.
Pedestrian Crosswalk Safety at Nonsignalized Crossings During Nighttime: Use of Thermal Video Data and Surrogate Safety Measures
Authors: Fu Ting , Miranda-Moreno Luis , Saunier Nicolas
Published: December 2016

This paper proposes a methodology to evaluate crosswalk pedestrian safety at nighttime by using surrogate safety measures derived from thermal video data. The methodology is illustrated for two unsignalized crosswalk locations in downtown Montreal, Quebec, Canada. Video recordings from a thermal camera were used to compare nighttime and daytime safety conditions with surrogate safety measures that included vehicle approaching speed, postencroachment time (PET), yielding compliances, and conflict rates. A disaggregate measure of pedestrian exposure that excludes noninteracting road users is also proposed. A thermal camera was used to alleviate issues pertaining to low visibility at night for video analysis when road users, especially pedestrians, are difficult to track. The results showed that the thermal-video–based methodology could effectively collect interaction data at night regardless of lighting conditions. Through the use of thermal video data and the methodology proposed in this paper, the interactions between crossing pedestrians and motor vehicles, with related measures such as PET and speed, could be analyzed to evaluate the effect of different crosswalk treatments on pedestrian safety in low-visibility conditions.
Countdown Pedestrian Signals With and Without the Flashing Hand: Field Study
Authors: DeLaere Gregory M. , Van Houten Ron , Shurbutt Jim
Published: December 2016

As part of a proposed change in the Manual on Uniform Traffic Control Devices, the effects of removing the flashing “Don’t Walk” (FDW) signal from the countdown pedestrian signal (CPS) is being considered. Field research conducted 10 years ago found later pedestrian crossing finishing times when a CPS without the FDW was compared with a CPS plus FDW signal, although there was no increase in the percentage completing crossing after cross traffic was released. Results also indicated a slight decrease in pedestrians running during the CPS alone condition. The purpose of the present study was to replicate systematically the Singer and Lerner field research 10 years later while increasing the number of sites where data were collected (from two to four) and collecting baseline, treatment, and follow-up data at each site. Other differences for this study consist of including both one-way and two-way intersections, different speed limits, and different buffer times. Results of this study found statistically significant decreases in pedestrians who were still in the crosswalk when cross traffic was released at three of the four sites when the FDW was removed from the clearance phase. Additionally, an increase in the number of pedestrians running was detected at some of the sites during the CPS alone condition. Therefore, it does appear that removing the FDW signal from the CPS would result in an increase in the number of pedestrians who reach the opposite side of the crosswalk without interfering with cross traffic.