Kendra K. Levine's blog

Bus Bunching Explained Visually

 

Any bus rider knows what a problem bus bunching can be. (Anybody riding AC Transit's 51B to campus lives with this daily.) It's a popular research topic, with many articles and reports exploring the causes and solutions to prevent bunching.

ITS PhD student Lewis Lehe and designer Dennys Hess have developed visualization to explain why bus bunching happens. (You need to use Chrome.) Go try it out. CityLab and Metafilter are talking about it.  

Lehe has made many other visualizations explaining transportation phenomena like gridlock vs. bottlenecks and traffic waves. You can see more of his work on setosa.io

On Positive Train Control


flickr photo shared by m01229 under a Creative Commons ( BY ) license

It's been almost a week since the Philadelphia train derailment and people the question remains - would postive train control prevented the incident

What is potive train control? The Federal Railorad Administation (FRA) defines it as: "Positive Train Control (PTC) systems are integrated command, control, communications, and information systems for controlling train movements with safety, security, precision, and efficiency." Its deployment is mandated in the Rail Safety Improvement Act of 2008 by December 31, 2105. There is still a ways to go. 

The Association of American Railroads notes the enormity of the task

PTC is an unprecedented technical and operational challenge. Since enactment of RSIA, railroads have devoted enormous human and financial resources to develop a fully functioning PTC system over the 60,000 miles that are subject to the PTC mandate. Progress to date has been substantial. Railroads have retained more than 2,400 signal system personnel to implement PTC and has already spent $5 billion on PTC development and deployment. Railroads expect to spend more than $9 billion before development and installation is complete.

A GAO report from 2013 outlines a number of challenges facing OTC roll out, echoing AAR's concerns about the complexity of the system and the timeline not being feasible. 

The week before the Philadelphia derailment, the FRA also issued a research brief about PTC across shared networks that could be used by multiple railroads. 

For more research about PTC you should go check out TRID

 

Amtrak Train Derailment in Philadelphia: Time to think about rail and infrastructure safety

Photo credit: AP 

Last night Amtrak Northeast Regional Train 188 frp, Washington to New York derailed in Philadelphia killing 7 and injuring more than 200 passengers and crew. The cause of the derailment is not yet known but the data recorders have been recovered and are currently being analyzed. This has been one of the biggest passenger rail crashes in recent times and investigators are looking at a number of factors. It should be noted that while rail fatalities have climbed in recent years, derailments are rare. You can find more rail safety data here.

Vice President Joe Biden, one of Amtrak's Northeast Regional's biggest proponents gave an emotional reaction. Today Congress rejected a funding increase proposal to Amtrak to make capital improvements. The last time Congress passed an Amtrak bill, it was after another fatal train crash - the 2008 Los Angeles Metrolink crash.  This week was also dubbed "Infrastructure Week" by USDOT Secretary Anthony Foxx as he's been campaigning for increased investment in our nation's infrastructure needs. (For a take on the current state of the US's infrastructure needs, check out Last Week Tonight with John Oliver (NSFW)). 

 

Modeling network of vehicles in a heterogeneous non-urban environment

USMC-111104-M-YP696-003

Last week's Friday Seminar featured EECS Professor Ruzena Bajcsi and grad student Katie Driggs-Campbell presenting their research on developing driver models to address issues in heterogeneous environments (with autonomous vechiles and human drivers). Their research group has focused on the relationship of the individual driver in the environment around them. Modeling driver behavior is important because driver distraction makes drivers unpredictable and leads to significant safety implications. NHTSA reports in 2013, 424,00 people were involved in distracted driving crashes with 3,154 fatalities. Even with the rapid advances in automated and connected vehicle technology,  Bajcsy forseees heterogeneous environments for at least the next 15 years, so the ability of the models controlled the autonomous vehicles will need to understand potential behaviours of human drivers. To develop the models using control theory, Driggs explained how they used human-in-the-loop driving simulations to better detect different stages of driver distraction and maneuvering. These models can then be used for semiautonomous vehicular control

Stay tuned for this Friday's Seminar, which is the last of the semester. ITS gradstudent Haoyu Chen will present his dissertation research on improving public transit at city-wide scales. 

California's new ambitious greenhouse gas reduction targets.


flickr photo shared by Malingering under a Creative Commons ( BY-NC-ND ) license

Yesterday California Governor Jerry Brown issued an executive order establishing the state's greenhouse gas reduction target 40 percent below 1990 levels by 2030 (Executive Oder B-30-15).  This new executive order is another step reducing California's greenhouse gas emissions after the California Global Warming Solutions Act of 2006 (AB 32) which set reduction targets to 1990 levels by 2020. LBNL models predict we're on target to meet the 2020 goals but will need more effort ot meet the ultimate 2050 goals. 

Research in this area demonstrates that to achieve 80% greenhouse gas reductions by 2050 that moving to low-carbon and renewable energy will be important, but also investment in carbon capture and sequestration (CCS) technology. Integrated climate protection into planning and land use policies, such as smart growth planning, will also help California meet its targets. Much of the technological innovations to cut greenhouse gas emissions by 2050 hinges on the role of electricity to move away from carbon based fuels across economic sectors. And yes, high-speed rail could also be part of the solution

Monitoring Traffic for Incidents and Extreme Congestion Events


flickr photo shared by canihazit under a Creative Commons ( BY-NC-ND ) license

Last week's Friday Seminar welcomed back ITS alumn, now Univeristy of Illinois Urbana-Champaign Assistant Professor, Dan Work. He presented some of his work in the area of monitoring traffic data to better responde to incidents and extreme congestion events. The talk began with focus on how his group uses the app TrafficTurk for low-cost traffic sensing, which has been used in managing big events like homecoming weekend at University of Illinois and the Farm Progress Shows in Decatur, IL (where over 100,000 people flock for the event). He then talked about how he's used this sensing data to more quickly respond to traffic incidents through multiple model particle filtering. He concluded the talk preseting some preliminary results from New York City taxi data (which is shared here as open data) on the congestion in the city following Hurricane Sandy. The data shows that there was not much congestion during evacuation, as there was a system and a plan in place, but that the extreme congestion after the storm shows a need for better post-event planning and coordination. 

You can find more of Work's publications (and source code) here

Connected/Autonomous Vehicles, Ownership, and DMCA: What will vehicle ownership mean in the future?


flickr photo shared by sidehike under a Creative Commons ( BY-NC-SA ) license

Today Wired ran a story about John Deere's assertion that purchasing one of their tractors is "an implied license for the life of the vehicle to operate the vehicle." The key issue is not the hardware, but the software and the ability to access and modify it.  Using DMCA, many vehicle manufacturers are submitting comments to the Copyrights Office that modifying their software in a form of piracy. So legally, is this the end of ownership as we know it?

The questions and concerns about this legal development has been brewing for some time, but as the internet of thing comes closer to being a reality more people are calling into question our existing copyright and patent system and their limitations. (Even John Oliver discussed patents!)

This issue has been on the radar of USDOT's ITS JPO for a while now, especially the policy implications for connected and automated vehicles. The critical issue is the balance of open source software and concerns about cybersecurity and safety. Some of the promise of connected/automated vehicles, is the rich big data environments they will operate in but how can the industry cooperatively get there despite concerns about privacy and innovation? There is also the looming issue of liability for connected/autonomous vehicles, much of which hinges questions of safety and the perception of risk. 

It will be interesting to see how all of this develops and the rules are made. 

Accessibility and the Sharing Economy: Leap, Uber, Lyft and ADA requirements


Creative Commons licensed ( BY-NC-SA ) flickr photo shared by pix.plz

The disruption of traditional transportation by startups like Uber and Lyft has created waves and caused many cities and agencies to re-examine how they regulate taxis and the livery system. Now it looks like upstarts like Leap and Chariot, aiming to disrupt public transit, may be on the same course. 

It was reported today that last month a complaint was filed with the Department of Justice because Leap has failed to make its buses accessible to wheelchairs. This echoes similar concerns that has been expressed about Uber and Lyft. It is important to note that the Americans with Disabilities Act (ADA) does not require automobiles to be accessible, while other types of vehicles (vans and buses) must be accessible. 

Transit is crucial in providing accessible mobility options for people with disabilities, which is important to the quality of life. There has been much research focused on how to improve these transportation networks, including using taxis as a potential form of paratransit. TNCs like Uber and Lyft have improved accessible for some groups, it has been inconsistent. This review of Uber from the American Foundation for the Blind (AFB) points out the service works well with iOS, but that they Android app is not accessible. There is also the issue that riders with guide dogs might be refused a ride and "there appears to be no legal recourse that can be taken under the ADA at this time." The AFB has since filed a lawsuit against Uber and the DOJ now says Uber must comply with ADA. These sorts of regulatory growing pains seem to be a part of disruptive transportation companies maturity, which is why the complaint filed against Leap isn't very surprising. 

The Leap case also raises the existential question - what does it mean to be a transit service? Part of Leap's argument is that they do not provide transit, rather they connect riders with an operator. This is the same position Uber and Lyft have taken with regard to its relationship with riders and drivers, which also has a lawsuit in the courts. Leap and Chariot are basically modern jitneys that compliment existing services and jitneys are not exempt ADA requirements.

New article: Impact of Parking Prices and Transit Fares on Mode Choice at the University of California, Berkeley


creative commons licensed ( BY-NC-ND ) flickr photo shared by stevejin

A new article from the Transportation Research Record is especially close to home, examining what it would take to reduce the rate of single-occupancy vehicle community here to UC Berkeley. In "Impact of Parking Prices and Transit Fares on Mode Choice at the University of California, Berkeley," Frank Proux, Brian Cavagnolo, and Mariana Torres-Montoya use data from a campus-wide survey and discrete choice models to investigate. They find:

The University of California, Berkeley, and the City of Berkeley sought to reduce single-occupancy-vehicle commute trips to the campus as a means to reduce negative transportation externalities and to fulfill their environmental emissions reduction goals. This paper reports on the evaluation of policy scenarios to assess the potential impact of parking pricing and transit fare subsidies on the overall mode share of the University of California, Berkeley, community. A mode and parking choice model was developed on the basis of a biennial campuswide transportation and housing survey; policy alternatives were tested with a sample enumeration. The discrete choice model selected for policy analysis was a nested logit model calibrated on a randomly selected subsample of n 5 3,371 individuals and validated against the remaining 814 campus commuters. Factors found to influence mode choice significantly in this model included travel times and costs, gender, student status, age older than 70, and home location topography. Campus affiliates also appeared to have a predisposition to walk, which likely reflected the large student population that lived close to campus. A drive-alone value of time of approximately $30 per hour was calculated. Policy scenario tests suggested that, to spur a significant mode shift away from that of driving alone, parking pricing reforms would need to be used in tandem with incentives to use alternative modes. Such an approach might garner additional political support, especially if commuters who drove alone received the indirect benefits of transit subsidies, such as reduced congestion and a less competitive parking market. Policies designed to mitigate the regressive impacts of parking fees were tested also.

The full paper can be found here. If parking pricing and demand is of interest to you, then you should check out the rest of the issue. One of the other articles covers residential parking permits in the city of Berkeley

Library Closed March 23-27


creative commons licensed ( BY-NC-SA ) flickr photo shared by MoDOT Photos

We're closed this week, March 23 through March 27, for Spring Break. It's also National Work Zone Safety Week, so expect the unexpected. We'll see you on Monday, March 30. 

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