Friday Seminar - Tasos Kouvelas on Adaptive Fine-tuning for Large-scale Nonlinear Traffic Control Systems

Traffic Light Tree

This week’s Friday TRANSOC Seminar has Tasos Kouvelas, Ph.D., Postdoctoral Researcher, University of California, Berkeley, presenting  “Adaptive Fine-tuning for Large-scale Nonlinear Traffic Control Systems.”

This talk introduces and analyzes a new learning/adaptive algorithm that enables automatic fine-tuning of Large-scale Nonlinear Traffic Control Systems (LNTCS), so as to reach the maximum performance that is achievable with the utilized control strategy. LNTCS have many applications in transportation, as with urban signal control or ramp metering, and yet their efficient design and deployment remains elusive due to the involved complexity and nonlinearities. Often, the deployment of a new algorithm (or the updating of an existing one) requires extensive fine-tuning before it reaches its best achievable performance. Typically, this fine-tuning procedure is conducted manually, via trial-and-error, relying on expertise and human judgment and without the use of a systematic approach. The proposed Adaptive Fine Tuning (AFT) algorithm is aiming at replacing the conventional manual optimization practice with a fully automated online procedure. The talk provides a detailed analysis of the algorithm as well as a step-by-step application description. Finally, application results of the algorithm to real-time fine-tuning problems of general LNTCS are presented using the commercial micro-simulation tool AIMSUN.

The seminar will take place today 4:00 PM in 406 Davis Hall. Please join us for a TRANSOC-sponsored Cookie Hour in the ITS Library at 3:30 PM.

Friday Seminar - Sebastien Blandin on Modeling, Estimation and Control of Distributed Parameter Systems

Istanbul highway traffic

This week’s Friday Seminar has Sebastien Blandin, PhD., Research Scientist, IBM Singapore Research Collaboratory, presenting “Modeling, Estimation and Control of Distributed Parameter Systems: Application to Transportation Networks.”

Scalar conservation laws expressing the evolution of traffic density have been extensively used for macroscopic traffic modeling and forward simulation using loop detector measurements. The mobile sensing paradigm allowing increased understanding of traffic flow motivates the need for novel partial differential equation results, of practical interest for real-time traffic operations. The research contributions of this work are centered on traffic modeling capabilities, data assimilation performances, and Lyapunov stabilizability guarantees. We propose a new 2X2 phase transition model of traffic flow able to account for classical traffic phenomena as well as heterogeneous driving behaviors. In the context of traffic information systems and filtering algorithms, we present one of the first numerical and analytical descriptions of the consequences of the emergence and propagation of shockwaves in traffic flow on estimates accuracy. Finally, we propose a Lyapunov stability result for the entropy solution to the transport equation using boundary actuation. The results presented in this work are instantiated on the Mobile Millennium system providing real-time traffic estimates in Northern California.

The seminar will take place on Friday, January 27, from 4:00-5:00 p.m. in 534 Davis Hall.

Friday Seminar - Nikolas Geroliminis on Traffic Systems

A (small) part of traffic-1

Today’s TRANSOC Friday Seminar has Nikolas Geroliminis, PhD., Assistant Professor, Urban Transport Systems Laboratory, École Polytechnique Fédérale de Lausanne (EPFL) presenting “The M6 of traffic systems: Macroscopic Modeling, Monitoring and Management of Multimodal Mobility.”

As more people and transport modes compete for limited urban space to travel, there is a need to understand how this space is used for transportation and how it can be managed to avoid traffic congestion. Our research seeks to shed some light in the modeling, planning and management of traffic flow for overcrowded cities with multimodal transport. We develop methodologies to model and understand the collective behavior for different types of multi‐modal systems, with emphasis in conflicts for the same road space (e.g. mixed traffic of buses and cars). The goal is to develop optimization tools on how to distribute city road space to multiple modes and to understand the level of accessibility for cities of different structures. We also investigate what type of real-time active traffic management schemes (congestion pricing, vehicle restriction, large scale traffic signal control) can improve mobility measures in a city. Until now traffic control systems in urban areas are locally programmed with little control over the impact of a micro-scale response to the macro-scale level. We build a hierarchical feedback control network of multiple levels. The validation of the modeling methodologies and the traffic management schemes are conducted in various and complex city structures scenarios using data from field experiments advanced micro-simulations.

The seminar will take place today 4:00 PM in 406 Davis Hall. Please join us for a TRANSOC-sponsored Cookie Hour in the ITS Library at 3:30 PM.

Automated Enforcement: Safety or Revenue?


Red light cameras and other forms of automated traffic law enforcement continue to generate controversy. This week, Iowa Governor Terry Branstad said that he is in favor of banning such devices and a bill was introduced in the Colorado legislature to ban photo enforcement. On the other hand, the Insurance Institute for Highway Safety found strong public support for camera enforcement in cities with such programs. Much of the debate in Iowa and elsewhere stems from disagreement over whether such enforcement enhances traffic safety or merely produces revenue in the form of fines. Privacy is also a big concern and some who object on these grounds also see a very disturbing trend towards privatization of law enforcement. US PIRG released a report in October which outlines some of the pitfalls in privatization, including conflicts of interest, political clout of vendors and possible intrusion in setting transportation policy.

Infographic: Bicycle Statistics in the US


A nice summary of bicycle ridership in the United States, as well as information pretaining to bicycle related fatalitities in 2008 and investment in bike-ped infrastructure. The Bay Are has done well - San Francisco is ranked Gold for bicycle friendly and Oakland is bronze. (via CFIRE)

Parking Minimums: Revisiting an old problem

New York Parking Structure

In today's New York Times, architecture critic Micahel Kimmelman looks at parking requirements for urabn development and he doesn't like how things have been going. 

For big cities like New York it is high time to abandon outmoded zoning codes from the auto-boom days requiring specific ratios of parking spaces per housing unit, or per square foot of retail space. These rules about minimum parking spaces have driven up the costs of apartments for developers and residents, damaged the environment, diverted money that could have gone to mass transit and created a government-mandated cityscape that’s largely unused. We keep adding to the glut of parking lots. Crain’s recently reported on the largely empty garages at new buildings like Avalon Fort Greene, a 42-story luxury tower near downtown Brooklyn, and 80 DeKalb Avenue, up the block, both well occupied, both of which built hundreds of parking spaces to woo tenants. Garages near Yankee Stadium, built over the objections of Bronx neighbors appalled at losing parkland for yet more parking lots, turn out never to be more than 60 percent full, even on game days. The city has lost public space, the developers have lost a fortune.

Streetsblog wonders what this endorsement for eliminating parking minimums might have on the Department of City Planning

This is not a new topic by any means. Donald Shoup's High Cost of Free Parking is a cornerstone of the field. Researchers from NYU have looked at the enforcement of New York City's minumum parking requirements and how proximity to transit affects the reuirements and the impact on housing affordability. There is also a thought that well-functioning off-street parking markets might be a solution. 

The Guardian discusses cycling safety in London

Were Cycle Superhighways designed to encourage 'vehicular cycling'?

This week's Guadian Focus Podcast discusses whether or not Boris Johnson's cycling superhighways have really improved cycling for the London area, in light of yet another cycling death. A study from 2010 questions shows that fatality rates did not drop between 1992-2006. Here's a map of cycling accidents in London between 2000 and 2008. Despite Johnson's proclamation fo 2010 being "London's year of cycling," ultimately cycling success will depend on public safety

Friday Seminar - Jeff Lidicker on Pavement Resurfacing Policy for Minimization of Life-cycle Costs and Greenhouse Gas Emissions

Pot hole and dent - #71/365

Tomorrow's TRANSOC Friday Semiar has Ph.D. candidate Jeff Lidicker presenting, "Pavement Resurfacing Policy for Minimization of Life-cycle Costs and Greenhouse Gas Emissions."

In recent decades pavement management optimization has been designed with the objective of minimizing user and agency costs.  However, recent analyses indicate that pavement management decisions also have significant impacts on life-cycle GHG emissions.  This study endeavors to expand beyond minimization of life-cycle costs, to also include GHG emissions.  We extend previous work on the single-facility, continuous-state, continuous-time optimal pavement resurfacing problem, to solve the multi-criteria optimization problem with the two objectives of minimizing costs and GHG emissions. Results indicate that there is a tradeoff between costs and emissions when developing a pavement resurfacing policy, providing a range of GHG emissions reduction cost-effectiveness options.  Case studies for an arterial and a major highway are presented to highlight the contrast between policy decisions for various pavement and vehicle technologies.

The seminar will take place on December 9 at 4:00 PM in 212 O'Brien Hall. (That's a new location!) There won't be a Cookie Hour this week as well. We'll see you in the new year!

How much longer do we have to wait for cars that drive themselves?

Google Self-Driving Car

Today Greater Greater Washington blogged about the prospect of self-driving cars.

Whether we are prepared for it or not, the next revolution in transportation will be here soon, and it won't be streetcars, monorails, segways, or electric vehicles. It will be self-driving cars, and the adoption of this technology will change everything we accept as a given in the field of transportation planning.

They also link to a Washingtonian interview with Michael Pack, director of the CATT Laboratory at the University of Maryland, and noted transportation technologist. He sees autonomous vehicles as a potential solution for congestion, "Completely automated cars that take the driver out of the equation, communicate with one another, and can travel at high speeds within six inches of one another."

Will Hansfield on Greater Greater Washington projects that we might see self driving cars commercialy viable in the US in the next 7-12 years. Given the clip of research, it might not be far off. Looking at "intelligent vehicles" research in TRID, automation is trend that has been becoming more common over the years. From cyber cars to intercontinental van journeys, integrated systems for autonomous vehicles are coming.

The PATH program from ITS Berkeley has been looking at autonomous vehicles for quite a while now. Though the most famous driverless cars might be the new fleet from Google. Sorry KITT.

Friday Seminar - Ilgin Guler on Strategies for Sharing Bottleneck Capacity among Buses and Cars

let photo speak...

Tomorrow's TRANSOC Friday Seminar features Ph.D. candidate Ilgin Guler presenting, "Strategies for Sharing Bottleneck Capacity among Buses and Cars."

Buses that operate in mixed traffic can be impeded by car congestion, leading to unreliable and slow bus service. Conversely, buses that frequently stop to serve passengers can interfere with the movement of cars. To address these issues, exclusive bus lanes have often been used to segregate buses from other traffic. These exclusive bus lanes provide a means for buses to bypass car queues, thereby increasing bus speed and potentially decreasing the total person hours travelled on a network. In urban settings exclusive bus lanes are typically deployed by converting an existing general purpose lane to bus use only. However, in cases where bus flow is low, these lane conversions can increase the queuing and delays to cars. The problem is particularly acute at roadways bottlenecks, since cars now discharge from one less lane, even when the bus lane is unoccupied.

This research examines strategies for judiciously inserting cars between buses in ways that minimize the losses in a bottleneck’s car carrying capacity when bus demand is low. The idea entails sharing lanes among buses and cars in the vicinities of critical bottlenecks; and to have these shared lanes augment exclusive bus lanes that are deployed elsewhere throughout the network. The specific type of sharing strategy to be used near any given bottleneck would depend upon its operating conditions. In all cases the goal is to prioritize bus travel while minimizing the additional delays that this prioritization imparts to cars. Analysis unveils the ranges of bus demands for which the shared‑lane strategies are superior to ordinary lane conversions. We find that the shared-lane strategies have merit in many instances. Implementing these strategies for a real-world case study in Amman, Jordan produces promising outcomes: simulation analysis indicates that the delay savings to cars brought by the lane–sharing strategies are considerable. The proposed ideas can help increase the political acceptability of bus priority systems and promote public transportation in cities of various sizes.

The Seminar will be from 4-5pm in 406 Davis Hall. There will be no cookie hour precedding it this week, so you'll need to sort out your sugar fix some other way. 

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