This study develops a time-driven train performance simulation (TPS) model consisting of train traction module, track alignment module, and train control module, which is applied to emulate the movement of a train, calculate energy consumption, and estimate travel time, considering various vertical track alignments and operational controls. A numerical example is given in this study to demonstrate the features of the developed TPS, such as generating time varying operational measures (e.g., the tractive effort, resistance, acceleration rate, speed, and energy consumption, etc.) and calculating energy consumption and travel time. The most energy efficient train control, or called “golden run,” associated with various track alignments, speed limits, and schedule adherence are identified, while the impact of coasting locations to travel time and energy consumption is also assessed. A sensitivity analysis is conducted, and the relationship between model parameters and control variables are discussed.

Intersection-related crashes account for approximately 31% of fatal crashes in Minnesota and roughly 37% of those occurred at night, dusk, or dawn. Nationally, intersection-related fatal crashes accounted for 21% of all fatal crashes and 40% of those crashes occurred during dark, dusk, or dawn light conditions while only 25–33% of the vehicle miles traveled occur at night. Furthermore, Minnesota experienced 70% of its fatal crashes in rural areas, as compared to 58% nationally. As a result, rural intersections at night are at higher risk for fatal crashes than other locations in Minnesota. This research was part of Research Rep. No. MN/RC-2006-35, “Safety impacts of street lighting at isolated rural intersections—Part II.” This research evaluated the effectiveness of roadway lighting in reducing nighttime crashes at isolated rural intersections. A before-and-after study was used to evaluate the impact of lighting at 33 intersections with 3 years of before data and 3 years of after data. A Poisson regression model evaluated the change in the expected number of crashes after installation of lighting. Crash rate was calculated using this information and used to compare day versus night since volumes are expected to differ. Results indicated that the night crash rate was 37% lower after lighting was installed and was statistically significant. The change in daytime crash rate from the before to after period was 4% but was not statistically significant indicating that there was no overall change in crash rate during the analysis period due to other factors.

Decisions regarding the location of motorway interchanges need to be made very carefully because of their economic and political implications. In this paper, we present three optimization models aimed at assisting road administrations when they deal with motorway interchange location problems. The decisions are assumed to be made from the perspective of road users, with the objective of minimizing travel costs. Two of the models are based on existing hub location models, whereas the third one is a new model. The usefulness of the models in real-world situations is illustrated with a case study involving A25, one of the most important Portuguese motorways. When applied to this case study, the new model performed in general clearly better than the other two.

This paper proposes a methodology to determine the optimum maintenance frequencies for the components of an electric railway overhead contact line system. This methodology is aimed at improving the reliability and availability of each component within its operational context and calculates the maintenance frequencies according to the criticality of each component, the importance of the area in which they are installed, and the component performance. The available maintenance team resources are also taken into account in order to optimize the frequencies and make them feasible for the maintenance team. The proposed methodology uses statistical and optimization tools to take advantage of the information obtained through the careful analysis of the historical data related to the system performance, which allows an objective determination of appropriate maintenance frequencies. Furthermore, it allows establishing the frequencies in a dynamic way through a feedback process. To prove the usefulness of the proposed methodology, a case study is presented in which maintenance frequencies of some components of the overhead contact line of the Spanish railway network are determined.

Lane changing maneuvers could have a substantial influence on traffic flow characteristics as a result of their interfering effect on surrounding vehicles. The interference effect of lane changing is more pronounced when heavy vehicles change lanes compared to when passenger cars undertake the same maneuver. This is due to the physical effects that the heavy vehicles impose on surrounding traffic. This paper investigates and compares the traffic flow characteristics which influence the lane changing behavior of heavy vehicle and passenger car drivers on freeways under heavy traffic conditions. A trajectory data set comprising 28 heavy vehicle and 28 passenger car lane changing maneuvers is analyzed in this study. The results suggest a substantial difference exists between the traffic characteristics influencing the lane changing behavior of heavy vehicle and passenger car drivers. Heavy vehicles’ speed changes little during a lane changing maneuver. Heavy vehicle drivers mainly move into the slower lanes to prevent obstructing the fast moving vehicles which approach from the rear. However, passenger car drivers increase their speed according to the speeds of the lead and lag vehicles in the target lane. They more commonly move into the faster lanes to gain speed advantages.

Traffic incidents are a major source of travel uncertainty, imposing substantial costs on the transportation system. Sometimes, an incident can result in one or more secondary incidents, which can be particularly problematic. To identify roadways where multiple secondary incidents are more likely to occur and analyze primary and secondary incidents, an innovative analysis method based on a detailed incident data set from Hampton Roads, Virginia was developed. Incidents occurring on major freeways are categorized on a three-point ordinal scale as (1) an independent incident, i.e., an incident not associated with any secondary incidents; (2) one primary-secondary pair; and (3) one primary with two or more secondary incidents in the same or opposite directions. This scale captures event adversity from a traffic management perspective, with the last category capturing multiple secondary events. To quantify associations with key factors that include incident characteristics, roadway geometry and traffic flow, ordinal regression models are estimated. The results indicate that longer duration crashes, shorter segments, and heavy traffic are associated with higher propensity for secondary incidents. Furthermore, multiple-vehicle involvement and lane blockage are associated with multiple secondary incidents. The findings provide engineers and planners with valuable information on targeting service patrols in areas that are more prone to multiple secondary incidents. Overall, this research contributes by characterizing and analyzing complex events involving secondary incidents using rigorous statistical methods.

No track thermoplastic is a relatively new thermoplastic traffic marking material which can be installed on newly constructed asphalt pavement shortly after finishing paving operations. The main objectives of this study are (1) to develop a test procedure that can be used to determine whether a thermoplastic traffic marking is a no track thermoplastic traffic marking and (2) to run field tests to obtain performance data through real applications of industry-proclaimed no track thermoplastic traffic markings. Sixteen transverse lines were installed in the field for performance evaluation. The research team measured several parameters in the field such as appearance, retroreflectivity, and color. By comparing the testing parameters between no track and regular thermoplastic traffic markings, the research team intended to select a parameter that can be used to develop technical specifications to help decision makers define no track thermoplastic traffic markings. It was found that the best parameters that can be used to define a no track thermoplastic traffic marking were the CIELAB $\Delta E^{\ast }$ value and the CIE94 color tolerance $\Delta E_{94}^{\ast }$ . These two parameters were proposed by the International Commission on Illumination and have been used extensively for measuring color differences. As compared to other testing parameters, the change of these two parameters with time is more consistent and the selected no track thermoplastic traffic markings produced significantly lower $\Delta E^{\ast }$ and $\Delta E_{94}^{\ast }$ values as compared to the regular thermoplastic traffic marking. The research results have the potential to be used by decision makers to develop technical specifications to guide the real engineering applications of no track thermoplastic traffic markings.

This research aims at developing a system of real-time simulation-based dynamic traffic model under mixed traffic flow conditions. The system consists of two layers, namely, simulation layer and real-time control layer. The system is implemented based on rolling horizon approach, which is advanced for each stage; thus real-time data can be incorporated within the framework. In order to predict normative, as well as predictive, information, a simulation-based dynamic traffic assignment model is employed within each stage. Empirical data for a real city network, such as flows from vehicle detectors, are used to validate the model in a real-time environment. The values of mean absolute percentage error and root-mean-squared percentage error are within 15%, and the results show promising agreements between observed and simulated flows.

This paper presents an analysis of the dynamics of evolution of multiairport systems worldwide that can help to guide their effective development in the future. Given the capacity constraints on existing major airports, the development of multiairport systems is going to be a key mechanism by which air transportation systems around the world will be able to meet future demand. In order to better understand how these systems will evolve, a systematic case study analysis of 59 airport systems worldwide was performed. The analysis showed significant differences in the evolution of multiairport systems across world regions. In the United States and in Europe, the recent development of multiairport systems primarily involved the emergence of secondary airports. This dynamic was driven by the entry of low-cost carriers seizing the opportunity of using existing airport infrastructure but also by the barriers and opposition to the construction of green field airports. In Asia, multiairport systems have generally evolved through the construction of new high capacity airports, due to a much weaker set of available airports, high-perceived benefits of strong growth of traffic and weaker opposition to the construction of airports. This study suggests that, in the United States and in Europe, protecting existing underused airports will be key to meeting future demand. In Asia, where the existing underused airport infrastructure is weak and where projections of high volume of demand are high, there is the need to apply a dynamic approach to develop multiairport systems by reserving land area that can later be developed into airports.

High-occupancy vehicle (HOV) lanes are employed in many cities as a traffic congestion mitigation technique. These lanes are intended to provide a travel time benefit to carpools and buses, providing an incentive to choose those modes. The time and frustration involved in finding and using HOV lane access points may act as a deterrent to HOV lane use. Thus, proper planning of HOV lane access may be able to improve convenience for potential users, increasing HOV lane utilization. This paper investigated the possible relationship between the time required to access the HOV lane and travelers’ choice of HOV lane as their mode. Additionally, the distance to HOV lane access points and the type of access point were examined for their influence on HOV lane use rates. It was concluded that neither the type of HOV lane access point (for example, a T-ramp versus a slip ramp) nor the added time necessary to access the HOV lane were significant factors in HOV lane use rates. Instead, the convenience of carpool formation and the convenience of HOV lane access to traveler’s origins and destinations were found to be the most important factors in HOV lane use rates.

A large deal of research has been conducted on toll roads to better comprehend the characteristics of the tolling operations. Several researchers indicated that toll-lane processing time (or service time) is the most significant key parameter in calibrating simulated toll plazas and one of the central variables affecting toll-lane capacity. This paper analyzes the effects of various factors on toll-lane processing times including traffic characteristics, vehicle characteristics, and toll plaza characteristics. The proportional odds augmented multivariate adaptive regression splines (MARS) model outperformed the proportional odds model and was used as the final model in interpreting the results. Results indicate that plazas charging higher tolls and plazas requiring drivers to pay with inexact bills have larger processing times. Increased demand and increased interarrival times at the toll plaza’s outermost right lane also have higher processing times. Finally, results indicate that processing times during the p.m. peak hour are higher than the a.m. peak hour.

This paper presents an extensive investigation regarding the impacts of green signal countdown devices (GSCD) on the intersection safety and efficiency, based on field observation of critical driver and vehicle related parameters at two similar intersections (one with GSCD and the other without GSCD) in Shanghai. Statistical analysis results have revealed that the installation of GSCD can (1) encourage drivers to pass the stop-line during the amber time with higher speeds and thus result in better utilization of the amber time and increased capacity of the intersection approach; (2) smooth the driver’s response to the phase transition and effectively prevent the sudden change of speeds; (3) effectively eliminate the intersection dilemma zones by allowing the drivers to envision the phase transition and make decisions in advance; and (4) significantly reduce the number of red-light violations. Despite its effectiveness in facilitating the driver decision-making process, the installation of GSCD may adversely increase the possibility of collisions with unexpected crossing vehicles or pedestrians due to the significantly increased speeds of vehicles approaching the amber time. The analysis results from this study will offer the basis for traffic practitioners, researchers, and authorities in China to assess the impact of GSCD with respect to its operational and safety performance, and propose guidelines for its proper field installation.