Articles

Bottlenecks and the evening commute.

Motion

During the evening commute there are often bottlenecks as people try to get home on fixe routes with finite capacity. Vickrey's "Congestion Theory and Transport Investment" (1969) decribes the problem of commuters trying to pass the bottleneck. A recent paper, "The evening commute with cars and transit: Duality results and user equilibrium for the combined morning and evening peaks" by Eric Gonzales and Carlos Daganzo tackles the commute problem looking at both the evening and morning commute, since mode travel decisions are often made based upon the travel needs for the whole day. 

The paper then considers both the morning and evening peaks together for a single mode bottleneck (all cars) with identical travelers that share the same wished times. For a schedule penalty function of the morning departure and evening arrival times that is positive definite and has certain properties, a user equilibrium is shown to exist in which commuters travel in the same order in both peaks. The result is used to illustrate the user equilibrium for two cases: (i) commuters have decoupled schedule preferences in the morning and evening and (ii) commuters must work a fixed shift length but have flexibility when to start. Finally, a special case is considered with cars and transit: commuters have the same wished order in the morning and evening peaks. Commuters must use the same mode in both directions, and the complete user equilibrium solution reveals the number of commuters using cars and transit and the period in the middle of each rush when transit is used.

The whole paper can be found here

Air-traffic demand and capacity during bad weather

Landing Incheon Airport

What should airlines and air traffic controllers do to structure flights when airspace is reduced due to bad weather? A new paper from the recent aviation themed Transportation Research Record (no. 2325) examines that question. In "Mechanisms for Equitable Resource Allocation When Airspace Capacity Is Reduced," researchers from University of Maryland explore how carriers can prioritize flights. 

During bad weather and under other capacity-reducing restrictions, FAA uses various initiatives to manage air traffic flow to alleviate problems associated with imbalanced demand and capacity. A recently introduced alternative concept to airspace flow programs is the collaborative trajectory options program, in which aircraft operators are allowed to submit sets of alternative trajectory options for their flights, with accompanying cost estimates. It is not clear that these sets of alternative trajectory options can be generated or evaluated quickly enough to respond to flow programs that arise unexpectedly or that the program is intended to be folded into a formal resource allocation mechanism. This research proposes (a) a meaningful, yet simple, way for carriers to express some preference structure for their flights that are specifically affected by flow programs and (b) a resource allocation mechanism that will improve system efficiency and simultaneously take these airline preferences into account. The results are compared with the events that could occur if an airspace flow program were run by using a ration-by-schedule approach, with or without the opportunity for carriers to engage in swaps among their own flights.

The full paper can be found here

Is the stereotype of of electric vehicle drivers changing?

Special parking for Ram Plug-in Hybrid Electric Vehicle (PHEV)

That's the question a new article from Transportation Researc Part F asks. In "Electric vehicle drivers’ reported interactions with the public: Driving stereotype change?", researchers from Oxford Brookes University interviewed drivers of electric vehicles about their perceptions of the general public. They found that the stereotype is in a state of flux as the market shifts. It is also shown that the drivers are important as ambassors for electric vehicles taking hold with the rest of the general public. 

Bad Moods and Risky Drivers

Road Rage*

There's a new article from Transportation Research Part F that explores a possible link between driver mood and risky driving. Researchers from Peking University's Department of Psychology tested to see how a good or bad mood could affect driving bevaior. From the paper, "Negative or positive? The effect of emotion and mood on risky driving"

This research explored how two states of affect, emotion and mood, would influence driver’s risky driving behavior through risk perception and risk attitude. An experiment and a survey were adopted to test the two paths. In this model, negative affect played an opposite and more powerful role compared to positive affect. Study 1 was an experimental study with four treatment groups. Participants watched one of four video clips (traffic-related negative, traffic-unrelated negative, positive and neutral) and different emotions were induced. Negative emotion significantly elevated drivers’ risk perception but such perception failed to develop an appropriate attitude for drivers. A more favorable risk attitude resulted in increased reports of speeding. Turning from a “point” effect to a similar “period” effect, a survey was carried out in Study 2 to explore the effect of positive and negative mood instead of emotion. Mood states affected drivers’ risky driving behavior through risk perception as well as risk attitude, which was in line with the results of Study 1. The “bad is stronger than good” effect and the two paths in the model were discussed.

The whole paper can be found here

Truck Emissions at Container Terminals

Port of Singapore

Freight and transportation are large producers of emissions and considered a good area to target for emissions reduction. How though? A new paper from Transportation Research Part E: Logistics and Transportation Review examines how queing optimization can help. "Reducing truck emissions at container terminals in a low carbon economy: Proposal of a queueing-based bi-objective model for optimizing truck arrival pattern," estimate emissions produced during truck idling and wait times at ports. 

This study proposes a methodology to optimize truck arrival patterns to reduce emissions from idling truck engines at marine container terminals. A bi-objective model is developed minimizing both truck waiting times and truck arrival pattern change. The truck waiting time is estimated via a queueing network. Based on the waiting time, truck idling emissions are estimated. The proposed methodology is evaluated with a case study, where truck arrival rates vary over time. We propose a Genetic Algorithm based heuristic to solve the resulting problem. Result shows that, a small shift of truck arrivals can significantly reduce truck emissions, especially at the gate.

You can read the full paper here

 

Valuation of Travel Time

Travel Time Map - Department of Transport - MySociety

There a new article in the new journal Economics of Transportation that examines how travel time is valued, how and what is considered, and what should be improved. Kenneth Small's "Valuation of Travel Time"

After decades of study, the value of travel time remains incompletely understood and ripe for further theoretical and empirical investigation. Research has revealed many regularities and connections between willingness to pay for time savings and other economic factors including time of day choice, aversion to unreliability, labor supply, taxation, activity scheduling, intra-household time allocation, and out-of-office productivity. Some of these connections have been addressed through sophisticated modeling, revealing a plethora of reasons for heterogeneity in value of time rooted in behavior at a micro scale. This paper reviews what we know and what we need to know. A recurrent theme is that the value of time for a particular travel movement depends strongly on very specific factors, and that understanding how these factors work will provide new insights into travel behavior and into more general economic choices.

The full article can be found here

10 Things You Should Know About the ITS Library

Need help finding material in the collection? Not sure which library has what you're looking for? Here is a brief list of ten things you should know about using libraries at the UC Berkeley campus. Looking for Davis? 

  1. The TRID database covers literature from around the world and is a great place to do subject searching on any technical or policy aspect of transportation. There are many other electronic article databases with which to find material. You should also try Google Scholar.

  2. Use OskiCat, the UC Berkeley catalog, to find books, technical reports, policy papers, conference proceedings and other material in the ITS Library and other UC Berkeley libraries. You can search the entire UC Library system with Melvyl (Next Gen).
  3. Electronic journals allow you to access articles anywhere and spend less time at the copy machine. You can search all E-Journals A-Z. For specific citations, Google Scholar may be useful if you are using the Berkeley network.
  4. Most material in the ITS Library circulates, so that you may borrow it. You can keep track of what you borrow and renew material through My OskiCat.
  5. You also have access and privileges at the other UC Berkeley libraries. Some of the ones that may be of particular interest to you include:
  6. Course Reserves material is located behind the Circulation Desk and you are welcome to come behind the desk and find material you need. Reserves circulate for two hours.
  7. ITS Graduate students may obtain a key to the library and use the library after 5:00 pm and on weekends. Ask in the ITS Office for details. There may be a small fee for a key deposit.
  8. You can connect to library and campus resources off campus with the Proxy Server.
  9. If you need books, reports, or other material that UC Berkeley does not own, interlibrary loan can help. Ask for items from other UC libraries through the "Request" feature in Melvyl. For other material, use the Main Library's Interlibrary Loan service.
  10. Sign up for a locker on the 4th floor and you'll have a handy, safe place to store your books. Bring your own lock and register the locker number at the Circulation Desk.

Library staff looks forward to assisting you in locating information and using library materials. Library staff Kendra K. Levine and Marissa Young and our student employees.

 

 

Finding Articles

Looking for articles? Here are some ways to help you conenct to the article you're looking for.

 

Looking for articles about a certain topic in transportation? Your best bet is to start with TRID. TRID is the most comprehensive database for transportation research. It contains articles and papers from peer-reviewed journals, conference proceedings, technical reports, and more.

Here is a video about getting started with TRID:

If you are looking for articles about subjects that might extend beyond transportation, you can find the apropriate database in this list of Article Databases by Subject. Some of good resources include:

  • Web of Science (UCB Access Only) Multidisciplinary database that covers science and engineering, social sciences, and arts and humanities.
  • Compendex (UCB Access Only) Contains scientific and techincal engineering research from 1884 to present.
  • JSTOR Contains journal articles from a wide range of subjects including economics, history, business, and planning.
  • Avery Index to Architectural Periodicals (UCB Access Only) Resources on architecture, city planning, and related fields.
  • Civil Engineering Database Covers publications, such as journals and conferences, from ASCE.
  • National Technical Reports Library (NTRL) (UCB Access Only) Contains reports from the National Technical Information Service, with full text of government funded research.  

If you a link to the full-text of the article isn't available through the database directly, try the UC-eLinks button, or Google Scholar

About the Library

The Harmer E. Davis Transportation Library houses one of the pre-eminent transportation collections in the United States. Established in 1948, the ITS Library serves the research needs of the Institute of Transportation Studies and the University of California system.

Hours

The ITS Library's hours are:

  • Monday through Friday: 1 p.m. to 5 p.m.
  • Saturday and Sunday: Closed

Location

The ITS Library is located at 412 McLaughlin Hall on the north-side of the UC Berkeley campus. Situated between McCone, O'Brien, and Bechtel, McLaughlin Hall faces out on Memorial Glade. The closest intersection to the library is at Hearst Ave. and Euclid Ave. Street parking may be available along Hearst or Euclid.


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You can contact the ITS Library through the following means:

  • Email: itslib@berkeley.edu
  • Phone: (510) 642-3604
  • Fax: (510) 642-9180
  • By mail:
    Harmer E. Davis Transportation Library
    412 McLaughlin Hall
    University of California at Berkeley
    Berkeley, CA 94720-1720

 

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