Traffic Operations and Management

Integrating Traffic Network Analysis and Communication Network Analysis at a Regional Scale to Support More Efficient Evacuation in Response to a Wildfire Event

Soga, Kenichi
Comfort, Louise
Zhao, Bingyu
Lorusso, Paola
Soysal, Sena
2021

As demonstrated by the Camp Fire evacuation, communications (city-to-city, city-to-residents) play important roles in coordinating traffic operations and safeguarding region-wide evacuation processes in wildfire events. This collaborative report across multiple domains (fire, communication and traffic), documents a series of simulations and findings of the wildfire evacuation process for resource-strapped towns in Northern California. It consists of: (1) meteorological and vegetation-status dependent fire spread simulation (cellular automata model); (2) agency-level and agency-to-residents...

A Network Model of Departure Time Choice with Spillovers and Merging Effects. Part I: Building Block

Lago, Alejandro
Daganzo, Carlos F.
2003

This paper presents a departure-time user equilibrium model that explicitly considers the most important determinants of congestion behavior in cities during the morning commute: different commuter origins, merge interactions and queue spillovers. The proposed model combines three previous works: the departure-time equilibrium theory in Vickrey (1969), the traffic flow model of Newell (1993) and the merge theory in Daganzo (1996). The paper examines the simplest possible network exhibiting the three important features and discusses the ensuing policy implications. The solution algorithm...

Moving Bottlenecks: A Numerical Method that Converges in Flows

Daganzo, Carlos F.
Laval, Jorge A.
2003

This paper presents a numerical method to model kinematic wave (KW) traffic streams containing slow vehicles. The slow vehicles are modeled discretely as moving boundaries that can affect the traffic stream. The proposed scheme converges in flows, densities and speeds without oscillations, and therefore can be readily used in situations where one wishes to model the effect of the traffic stream on the bottlenecks too. The approach is more accurate than Godunov's method in situations where the latter can be applied.

Mobile Device Data Analytics for Next-Generation Traffic Management

Macfarlane, Jane, PhD
Patire, Anthony, PhD
Deodhar, Kanaad
Laurence, Colin
2021

Quality data is critically important for research and policy-making. The availability of device location data carrying rich, detailed information on travel patterns has increased significantly in recent years with the proliferation of personal GPSenabled mobile devices and fleet transponders. However, in its raw form, location data can be inaccurate and contain embedded biases that can skew analyses. This report describes the development of a method to process, clean, and enrich location data. Researchers developed a computational framework for processing large scale location datasets....

California’s Freeway Service Patrol Program: Management Information System Annual Report Fiscal Year 2019-20

Mauch, Michael
Skabardonis, Alex
2021

The Freeway Service Patrol (FSP) is an incident management program implemented by Caltrans, the California Highway Patrol and local partner agencies to quickly detect and assist disabled vehicles and reduce non-recurring congestion along the freeway during peak commute hours. The first FSP program was piloted in Los Angeles, and was later expanded to other regions by state legislation in 1991. As of June 2019, there were fourteen participating FSP Programs operating in California, deploying 338 tow trucks and covering over 1,806 (centerline) miles of congested California freeways. The...

Distributing Synchronous Programs Using Bounded Queues, a coordinated traffic signal application

Zennaro, Marco
Sengupta, Raja
2005

This paper is about the modular compilation and distribution of a sub-class of Simulink programs [10] across networks using bounded FIFO queues. The problem is first addressed mathematically. Then, based on these formal results, a software library for the modular compilation and distribution of Simulink program is given. The performance the library is given. The value of synchronous programming for the next generation of traffic control value is discussed. The adoption of these tools seems to be the natural candidate to address the needs of the traffic engineers. As a case study we present...

A Variable Formulation of Kinematic Waves: Solution Methods

Daganzo, Carlos F.
2003

This paper presents improved solution methods for kinematic wave trafficc problems with concave flow-density relations. As explained in part I of this work, the solution of a kinematic wave problem is a set of continuum least-cost paths in space-time. The least cost to reach a point is the vehicle number. The idea here consists in overlaying a dense but discrete network with appropriate costs in the solution region and then using a shortest-path algorithm to estimate vehicle numbers. With properly designed networks, this procedure is more accurate than existing methods and can be applied...

Toll Pricing “Futures” Market Could Reduce Congestion and Increase Revenue

Fournier, Nicholas, PhD
Patire, Anthony, PhD
Skabardonis, Alexander
2024

Transportation agencies are increasingly relying on tolls to raise revenue and to mitigate congestion, but conventional fixed tolls do not necessarily encourage offpeak use of infrastructure, and high tolls can dampen economic productivity. Dynamically adjusting pricing based on demand can incentivize travelers to avoid peak traffic periods and shift it to other modes, but given the unpredictable nature of traffic, travelers lack the information necessary to accurately predict congestion, so dynamic pricing has minimal effect on demand. Dynamic toll pricing also poses equity concerns for...

Dashboard Cameras Combined with AI Provide an Affordable Method for Identifying Curb Usage

Arcak, Murat
Kurzhanskiy, Alexander
2024

The increasing reliance on transportation network companies (TNCs) and delivery services has transformed the use of curb space. The curb space is also an important interface for bikeways, bus lanes, street vendors, and paratransit stops for passengers with disabilities. These various demands are contributing to a lack of parking, resulting in illegal and double-parking and excessive cruising for spaces and causing traffic disturbance, congestion, and hazardous situations. How cities manage this public asset to support safety and the local economy relies on first understanding the usage...

Wildfire Evacuation Planning Can Be Greatly Enhanced by Considering Fire Progression, Communication Systems, and Other Dynamic Factors

Soga, Kenichi, PhD
Comfort, Louise, PhD
Zhao, Bingyu, PhD
Lorusso, Paola, MSc
Soysal, sena
2021

Wildfires have become a perpetual crisis for communities across California. For life-threatening wildfires, mass evacuation often becomes the only viable option to protect lives. Yet, looking back at recent events, including the devastating 2018 Camp Fire in Northern California, there are significant challenges associated with the evacuation process, such as multi-agency coordination, agency-resident communication, and management of extraordinarily high amounts of traffic within a short period of time. Currently, emergency planners use evacuation models that are typically based on existing...