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PSU Transportation Seminars

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Articles 31 - 37 of 37

Full-Text Articles in Engineering

Estimating Reliability Indices And Confidence Intervals For Transit And Traffic At The Corridor Level, Travis B. Glick Jan 2017

Estimating Reliability Indices And Confidence Intervals For Transit And Traffic At The Corridor Level, Travis B. Glick

PSU Transportation Seminars

As congestion worsens, the importance of rigorous methodologies to estimate travel-time reliability increases. Exploiting fine-granularity transit GPS data, this research proposes a novel method to estimate travel-time percentiles and confidence intervals. Novel transit reliability measures based on travel-time percentiles are proposed to identify and rank low-performance hotspots; the proposed reliability measures can be utilized to distinguish peak-hour low performance from whole-day low performance. As a case study, the methodology is applied to a bus transit corridor in Portland, Oregon. Time-space speed profiles, heatmaps, and visualizations are employed to highlight sections and intersections with high travel-time variability and transit low performance. …


Avoiding Bus Bunching: From Theory To Practice, Ricardo Giesen Jan 2017

Avoiding Bus Bunching: From Theory To Practice, Ricardo Giesen

PSU Transportation Seminars

The problem of bus bunching in a high frequency service has been largely studied in the literature.

This phenomenon is produced by three main factors

(i) the variability in travel time between stops; (ii) variations in passenger demand; and (iii) drivers’ heterogeneity.

In order to tackle this phenomenon a wide range of control strategies have been proposed, however, none of them had been successfully implemented on a large transit network with high frequency services.

In this talk, we present a control scheme based on a rolling horizon optimization problem that has been successfully implemented for real-time control of two high …


Pricing And Reliability Enhancements In The San Diego Activity-Based Travel Model, Joel Freedman Dec 2016

Pricing And Reliability Enhancements In The San Diego Activity-Based Travel Model, Joel Freedman

PSU Transportation Seminars

The estimation of demand for priced highway lanes is becoming increasingly important to agencies seeking to improve mobility and find alternative revenue sources for the provision of transportation infrastructure.

However, many modeling tools fall short of what is required for robust estimates of demand with respect to toll and managed lanes in two key areas:

  • The value-of-time is often aggregate and not consistently defined throughout the model system, and
  • The reliability of transport infrastructure is rarely taken into account.

This presentation describes an effort which implemented recommendations of the Strategic Highway Research Program C04 and L03\L04 tracks on pricing and …


Pursuing Vision Zero In Seattle – Results Of A Systemic Safety Analysis, Rebecca Sanders Jun 2016

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 …


Connected Vehicles And Rural Road Weather Management, Rhonda Young May 2016

Connected Vehicles And Rural Road Weather Management, Rhonda Young

PSU Transportation Seminars

Changing weather patterns and increases in extreme weather events has led to the deployment of more weather responsive traffic management strategies. As the transportation system moves towards a connected vehicle environment, questions arise as to how connected vehicle technology can support weather responsive systems. The presentation will discuss the use of connected vehicles in a rural environment as providers of mobile weather data. Two projects will be highlighted - a recently completed research project using passenger vehicle CAN-BUS data as weather surrogates, and the ongoing USDOT CV Pilot Deployment Project in Wyoming.


Measuring What We Value: Using Performance Measures To Achieve Goals, Chris Rall May 2016

Measuring What We Value: Using Performance Measures To Achieve Goals, Chris Rall

PSU Transportation Seminars

Performance measures are commonly used in transportation planning, but how effectively are public agencies using them, and to what ends?

Metro, ODOT and many cities use performance measures to evaluate investment choices and monitor progress. Drawing from Transportation for America’s report Measuring What We Value, and some of the most cutting edge examples of performance-based planning around the nation, Chris' presentation will step back to consider what makes a performance-based planning approach effective at achieving an agency’s goals.


Lighten Everyone's Load: Lidar Applications To Support Engineers, Planners, Scientists And More, Michael J. Olsen May 2015

Lighten Everyone's Load: Lidar Applications To Support Engineers, Planners, Scientists And More, Michael J. Olsen

PSU Transportation Seminars

Light detection and ranging (LIDAR) technology is reshaping the civil engineering profession and offers many unique advantages. National efforts such as the 3D Elevation Plan (3DEP) are helping increase the availability of LIDAR data. LIDAR is one of the crucial technologies that is transitioning the world of civil and construction engineering from 2D paper-based design to 3D digital design. The high spatial resolution and accuracy capabilities of LIDAR have led to increased efficiencies, improved analyses, and more informed decision making.

A further advantage of this dataset is that multiple people can use the same dataset for a variety …