Engineering Commons^™

Mesoscopic Modeling And Simulation Of Mixed Traffic Flow Of Buses And Vehicles, Yiting Zhu, Yun Yan, Zhaocheng He

Journal of System Simulation

Abstract: Aiming at the problem that the existing mesoscopic simulation models only convert buses into several standard vehicles and ignore the movement difference between buses and vehicles, a mesoscopic simulation model of mixed traffic flow is proposed. In the process of road driving, on the one aspect, we consider the feature that bus speed is usually lower than vehicle speed, and correspondingly establish the reduction function of bus speed; on the other aspect, we consider the influences of bus-station queue overflow on the adjacent lanes, and correspondingly construct the lane-based speed model of mixed flow.Moreover, we use the …

Examining Bicycle And Motorized Vehicle Speeds And Their Relationships In The Context Of Urban Roadways, Jaclyn Sue Schaefer

Dissertations and Theses

This thesis presents a compilation of papers exploring passenger car and bicycle speeds through their interactions with each other and with urban roadway factors.

First, following a concern raised in part of the traffic literature that a large mode shift toward bicycling may cause travel time delays and potentially exacerbate congestion instead of alleviate it unless bicycle lanes are installed, an empirical study detailing how the presence of bicycles on urban roads without bicycle lanes may affect passenger car speeds is presented. Pneumatic tube data from six predominantly low speed, low volume roads in Portland, Oregon were utilized to identify …

An Empirical Study Of The Impacts Of Bicycles On Passenger Car Speeds On Urban Roads Without Bicycle Lanes, Jaclyn S. Schaefer, Miguel Figliozzi, Avinash Unnikrishnan

Civil and Environmental Engineering Faculty Publications and Presentations

Higher bicycle mode share has been suggested as part of a solution to reduce the burden of congestion in urban areas. As strategies to promote bicycling are implemented, concerns have been raised by some road users and stakeholders citing simulation based traffic studies that indicate that an increase in the bicycle mode share generates major travel time delays via reduced vehicle speeds unless bicycle lanes are provided. The current research investigates the effects bicycles may have on motorized vehicle speeds on a variety of lower speed and volume urban roads without bicycle lanes. A detailed comparative analysis of passenger car …

Travel Behaviors Of Persons With Intellectual And Developmental Disabilities, Joseph C. Totten

Civil and Environmental Engineering Master's Project Reports

People with intellectual and developmental disabilities live different lives than the general population. Often prohibited from driving, persons with intellectual disabilities cite transportation as top concern, limiting their independence and freedom to live, work or recreate where and when they choose. Improving services for persons with developmental disabilities requires that engineers and planners understand how persons with intellectual disabilities travel, and what types of transportation are available to them. This report hopes to identify the availability of transportation options to persons with developmental disabilities such that planners, engineers and advocates can determine how altering the transportation system might affect persons’ …

Modeling The Impact Of Traffic Conditions And Bicycle Facilities On Cyclists' On-Road Stress Levels, Àlvaro Caviedes, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Past research efforts have shown that cyclists’ safety, stress, and comfort levels greatly affect the routes chosen by cyclists and cycling frequency. Some researchers have tried to categorize cyclists’ levels of traffic stress utilizing data that can be directly measured in the field, such as the number of motorized travel lanes, motorized vehicle travel speeds, and type of bicycle infrastructure. This research effort presents a novel approach: real-world, on-road measurements of physiological stress as cyclists travel across different types of bicycle facilities at peak and off-peak traffic times. By matching videos with stressful events, it was possible to observe the …

Transportation Impacts Of Affordable Housing: Informing Development Review With Travel Behavior Analysis, Amanda Howell

PSU Transportation Seminars

Planning for affordable housing is challenged by development policies that often do not differentiate between the travel patterns of residents of market-rate housing and those living in affordable units. The development review process generally requires an evaluation of the anticipated additional transportation demand that new development places on the system and an assessment of fees or improvements to mitigate these impacts.

However, industry standard guidelines for assessment of travel demand outlined within the Institute of Transportation Engineers (ITE) Trip Generation Handbook have been focused solely on vehicle trip rates for these traffic impact analyses. Given the public goals of providing …

Exploring The Determinants Of Vulnerable Road Users’ Crash Severity In State Roads, Álvaro Caviedes

PSU Transportation Seminars

Part of the Student Presentations from TRB

Pedestrians and bicyclists are the most vulnerable road users and suffer the most severe consequences when crashes take place. An extensive literature is available for crash severity in terms of driver safety, but fewer studies have explored non-motorized users’ crash severity. Furthermore, most research efforts have examined pedestrian and bicyclist crash severity in urban areas. This study focuses on state roads (mostly outside major urban areas) and aims to identify contributing risk factors of fatal and severe crashes involving pedestrians and bicyclists in state roads. The results seem to suggest that besides improvements …

Diseño De Un Sistema De Rutas Para El Acceso Y Salida De Los Estudiantes Del Programa De Ingeniería Industrial De La Universidad De La Salle En La Sede Candelaria, Brandon Andrés Ballesteros Barriga, Santiago Cruz Benjumea

Ingeniería Industrial

No abstract provided.

Transportation Impacts Of Affordable Housing: Informing Development Review With Travel Behavior Analysis, Amanda Howell, Kristina Marie Currans, Steven R. Gehrke, Gregory Norton, Kelly J. Clifton

Civil and Environmental Engineering Faculty Publications and Presentations

Planning for affordable housing is challenged by development policies that assess transportation impacts based on methodologies that often do not distinguish between the travel patterns of residents of market-rate housing and those living in affordable units. Given the public goals of providing affordable housing in areas with good accessibility and transportation options, there is a need to reduce unnecessary costs imposed by the potential overestimation of automobile travel and its associated impacts. Thus, the primary objective of this paper is to examine and quantify the influences of urban characteristics, residential housing type, and income on metrics commonly used to assess …

Advisory Bike Lanes In North America, Michael Williams

PSU Transportation Seminars

Despite being used successfully for decades in Europe, Advisory Bike Lanes are an emerging facility type in North America and can be an effective tool for communities wishing to provide bicycle lanes on streets that are otherwise too narrow to accommodate them. This talk will introduce the concept and operation of advisory bike lanes and look at some lessons learned from the early installations of this facility in the U.S. and Canada.

Getting To Know The Data: Understanding Assumptions, Sensitivities, Uncertainty, And Being "Conservative" While Using Ite's Trip Generation Data In The Land Development Process, Kristina Marie Currans

PSU Transportation Seminars

Many agencies rely on trip generation estimates to evaluate the transportation impacts of land development in urban and suburban areas alike. Over the past decade, substantial attention has been paid to one national set of guidelines—the Institute of Transportation Engineers (ITE) Trip Generation Handbook (2014) and corresponding Manual (2012)—focusing in particular to improve the use of these data and supplementary methods for urban contexts.

The purpose of this study is to explore the typical data provided in the Handbook, within the context of these new improved state-of-the-art methods. As ITE’s describes, “an example of poor professional judgment is to rely …

Addressing Data Challenges For Bicycle Crash Analysis, Eleni Christofa

PSU Transportation Seminars

Although an increasing number of separated bicycle facilities have been appearing across the US over the last few years, the majority of bicyclists are still traveling on roadways shared with motorized vehicles.

As a result, bicycles are essentially double exposed to safety risk, due to their interactions with both motorized vehicles and other bicycles. In addition to this double exposure, data challenges–such as a lack of continuous counts and bicycle crash data—complicate the assessment of bicycle safety further.

This research presents a bicycle crash analysis framework for estimating bicycle crash rates accounting for both bicycle and motorized vehicle exposure as …

Land Use Mix And Pedestrian Travel Behavior: Advancements In Conceptualization And Measurement, Steven Robert Gehrke

Dissertations and Theses

Smart growth policies have often emphasized the importance of land use mix as an intervention beholding of lasting urban planning and public health benefits. Past transportation-land use research has identified potential efficiency gains achieved by mixed-use neighborhoods and the subsequent shortening of trip lengths; whereas, public health research has accredited increased land use mixing as an effective policy for facilitating greater physical activity. However, despite the celebrated transportation, land use, and health benefits of improved land use mixing and the extent of topical attention, no consensus has been reached regarding the conceptualization and measurement of this key smart growth principle …

Webinar: Integrating Explicit And Implicit Methods In Travel Behavior Research: A Study Of Driver Attitudes And Bias, Tara Goddard

TREC Webinar Series

Car crashes are still a leading cause of death in the United States, with vulnerable road users like bicyclists and pedestrians being injured or killed at rates that outpace their mode share.

Planners, engineers, and advocates are increasingly adopting Vision Zero and Tactical Urbanism approaches and trying to better understand the underlying causes of dangerous roadway interactions. However, existing research into crash causation has focused on instrumental factors (e.g. intersection type, vehicle speed) while little research has probed the role of attitudes or socio-cognitive mechanisms in interactions between roadway users.

Social psychology suggests that attitudes and social cognitions can play …

Pursuing Vision Zero In Seattle – Results Of A Systemic Safety Analysis, Rebecca Sanders

PSU Transportation Seminars

Many cities are considering pursuing Vision Zero to eliminate traffic deaths, but may not know how to move beyond addressing past crash locations toward preventing future crashes. Systemic analysis, which looks at crash patterns to determine common characteristics associated with various types of crashes, shows promise in helping cities to identify problematic locations and treatments in the hopes of preventing future crashes.

This presentation will share results from part of Seattle’s Vision Zero effort – a multi-phased analysis of pedestrian and bicycle crash data aiming to help the City understand both where crashes have occurred and where they are most …

Utilizing High Resolution Bus Gps Data To Visualize And Identify Congestion Hot-Spots In Urban, Nicholas B. Stoll, Travis B. Glick, Miguel Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Congestion and travel delay on urban roadways can influence the roadways’ operating costs and service attractiveness. This research used high-resolution bus data to examine sources of delay on urban arterials. A set of tools was created to help visualize trends in bus behavior and movement; these tools allowed larger traffic trends to be visualized along urban corridors and streets. With buses as probes and examining aggregated bus behavior, contoured speed plots were used to understand the behavior of roadways outside the zone of influence of bus stops. Speed plots were used to discover trends and travel patterns with only a …

Integrating Freight Into Livable Communities, Kristine M. Williams, Alexandria Carroll

TREC Final Reports

Where livability is a goal of the planning process, freight runs the risk of not being considered except as an afterthought or as something to be excluded. Yet, freight is an integral part of local economic development. Because economic prosperity is a key characteristic of livable communities, freight must be incorporated into the planning process. This study explores the relationship between freight and livability through a comprehensive literature review and case study research. The final report includes a menu of strategies and case study perspectives that highlight the importance of transportation and land use integration, interagency coordination, and context-sensitivity in …

Predicting Public Bicycle Adoption Using The Technology Acceptance Model, Benjamin T. Hazen, Robert E. Overstreet, Yacan Wang

Faculty Publications

Bicycle sharing programs provide a sustainable mode of urban transportation. Although cities across the globe have developed these systems for their citizens and visitors, usage rates are not as high as anticipated. This research uses the technology acceptance model as the basis to understand one’s intention to adopt bicycle sharing programs. Using survey data derived from 421 participants in Beijing, China, the proposed covariance-based structural equation model consisting of perceived quality, perceived convenience, and perceived value is found to predict 50.5% of the variance in adoption intention. The findings of this research contribute to theory and practice in the burgeoning …

Evaluating The Use Of Crowdsourcing As A Data Collection Method For Bicycle Performance Measures And Identification Of Facility Improvement Needs, Miguel A. Figliozzi, Bryan Philip Blanc

Civil and Environmental Engineering Faculty Publications and Presentations

This research developed a smartphone application called ORcycle to collect cyclists’ routes, users, and comfort levels. ORcycle combines GPS revealed route data collection with new questionnaires that try to elicit cyclists’ attitudes as well as comfort levels and factors that influence their perceived comfort and route choice. The new questionnaires were developed to better understand how cyclists’ comfort levels are affected by route characteristics, route stressors, safety reports, cyclists’ demographics, and cyclists’ cycling attitude. Preliminary results show that many trip characteristics, route choice factors, route stressors and demographic variables are correlated with comfort levels. ORcycle is the first statewide deployment …

Comparing Mode Shares For Non-Residential Destinations In Urban And Suburban Environments, Tasnia Subrin

Civil and Environmental Engineering Master's Project Reports

To ensure facility for multimodal transportation is one of the most important concerns in today's transportation sector, with initiatives being taken to make multimodal transportation popular. The built environment variables have a strong relationship with transportation mode choice, but whether that relationship holds true in urban and suburban neighborhoods in the same manner has not been considered. Using data for three non-residential land uses, this research explores whether the built environment variables in suburban areas influences mode share like it does in urban areas. We used survey data conducted at the establishments regarding respondents' travel characteristics from a previous study, …

Modeling Social Norms In Real-World Agent-Based Simulations, Rahmatollah Beheshti

Electronic Theses and Dissertations

Studying and simulating social systems including human groups and societies can be a complex problem. In order to build a model that simulates humans' actions, it is necessary to consider the major factors that affect human behavior. Norms are one of these factors: social norms are the customary rules that govern behavior in groups and societies. Norms are everywhere around us, from the way people handshake or bow to the clothes they wear. They play a large role in determining our behaviors. Studies on norms are much older than the age of computer science, since normative studies have been a …

Workshop Synthesis: Built Environment And Contextual Variables, Kelly Clifton, Pascal Perez

Civil and Environmental Engineering Faculty Publications and Presentations

This two-day workshop focused on the important issue of how to define, convey and understand the built environment context as it relates to transport decisions. The field has grown tremendously over the last few decades, fueled in part by the increasing availability of archived spatial data about the environment and geo-referencing activity and travel patterns. But there are persistent issues particularly with inconsistencies in data format or availability across locations that hamper efforts to advance our understanding across regions. Further, there are new challenges in how we communicate context to survey respondents, particularly in stated preference surveys. Much of the …

A Comparative Assessment Of Crowded Source Travel Time Estimates: A Case Study Of Bluetooth Vs Inrix On A Suburban Arterial, Fahad Fasha Alhajri

Civil and Environmental Engineering Master's Project Reports

Travel time is one of the most widely used measures of traffic performance monitoring for the transportation systems. It is a simple concept that refers to the time required to traverse between two points of interest. Travel time is communicated and used by a wide variety of audience such as commuters, media reporters, and transportation engineers and planners. Recent developments within the wireless communication area made it possible to collect travel time data at a relatively low cost. These emerging technologies include mobile phone based technologies, in-vehicle navigation technologies and automatic vehicle identification technologies. Although these technologies offer a great …

Transit Bus Fleet Age And Replacement Type Optimization, Miguel A. Figliozzi, Wei Feng, Jesse Boudart

Civil and Environmental Engineering Faculty Publications and Presentations

Due to recent budget and fiscal constraints, it is ever more imperative for transit agencies to manage their fleets in an optimal way. Fleet data have consistently shown that bus operational and maintenance (O&M) per-mile costs increase as buses age. From a purely economic perspective, there is a cost tradeoff between the lower O&M costs of newer fleets and their higher initial capital costs. This tradeoff has a significant impact on the optimal timing of purchase and replacement decisions. Utilizing realistic cost data and an optimization modeling framework, we analyze (a) the impact of purchase timing decisions on fleet per-mile …

Improving Vehicle Trip Generation Estimations For Urban Contexts: A Method Using Household Travel Surveys To Adjust Ite Trip Generation Rates, Kristina Marie Currans

Dissertations and Theses

The purpose of this research is to develop and test a widely available, ready-to-use method for adjusting the Institute of Transportation Engineers (ITE) Trip Generation Handbook vehicle trip generation estimates for urban context using regional household travel survey data. The ITE Handbook has become the predominant method for estimating vehicle trips generated by different land uses or establishment, providing a method for data collection and vehicle trip estimation based on the size of the development (e.g. gross square footage, number of employees, number of dwelling units). These estimates are used in traffic impact analysis to assess the amount of impact …

A Mechanism For Organizing Last-Mile Service Using Non-Dedicated Fleet, Shih-Fen Cheng, Duc Thien Nguyen, Hoong Chuin Lau

Shih-Fen CHENG

Unprecedented pace of urbanization and rising income levels have fueled the growth of car ownership in almost all newly formed megacities. Such growth has congested the limited road space and significantly affected the quality of life in these megacities. Convincing residents to give up their cars and use public transport is the most effective way in reducing congestion; however, even with sufficient public transport capacity, the lack of last-mile (from the transport hub to the destination) travel services is the major deterrent for the adoption of public transport. Due to the dynamic nature of such travel demands, fixed-size fleets will …

A Mechanism For Organizing Last-Mile Service Using Non-Dedicated Fleet, Shih-Fen Cheng, Duc Thien Nguyen, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

Unprecedented pace of urbanization and rising income levels have fueled the growth of car ownership in almost all newly formed megacities. Such growth has congested the limited road space and significantly affected the quality of life in these megacities. Convincing residents to give up their cars and use public transport is the most effective way in reducing congestion; however, even with sufficient public transport capacity, the lack of last-mile (from the transport hub to the destination) travel services is the major deterrent for the adoption of public transport. Due to the dynamic nature of such travel demands, fixed-size fleets will …

Taxisim: A Multiagent Simulation Platform For Evaluating Taxi Fleet Operations, Shih-Fen Cheng, Thi Duong Nguyen

Research Collection School Of Computing and Information Systems

Taxi service is an important mode of public transportation in most metropolitan areas since it provides door-to-door convenience in the public domain. Unfortunately, despite all the convenience taxis bring, taxi fleets are also extremely inefficient to the point that over 50% of its operation time could be spent in idling state. Improving taxi fleet operation is an extremely challenging problem, not just because of its scale, but also due to fact that taxi drivers are self-interested agents that cannot be controlled centrally. To facilitate the study of such complex and decentralized system, we propose to construct a multiagent simulation platform …

Planning Of Optimal Transit System Design, Yongning Liu

Theses

This study presents a methodological approach for finding an optimal design of bus transit service in an urban transportation corridor with elastic demand and under various objective functions. Service design decision variables to be optimized include the route length, route density, headway, number of stops and stop spacing pattern. The objective functions that optimize the transit system design include: minimizing operator cost, maximizing profit, minimizing sum of operator and user costs and maximizing the users' net benefits.

The analysis uses an elastic demand function wherein the number of trips are sensitive to the quality of service provided and price charged …

A System Dynamics Model To Test Urban Transportation Policy Alternatives, John Paul Burtle

Retrospective Theses and Dissertations

This study investigates the structure of urban transportation systems, the bases of commuter mode selection, and the effects of alternate transportation system management policies. The study was based on the hypothesis that changes in transportation system management policies are possible which will significantly increase the demand for public transportation in urban areas.