UCTC Research Abstracts 1995-1996

Dissertation Research

Faculty Research:

The following projects, submitted by faculty members of the University of California, were evaluated and selected for funding based on a peer review process.  

Economic Gains and Losses from Highway Corridors
Marlon G. Boarnet, Urban and Regional Planning, Irvine

This study will test the hypothesis that economic growth near urban highways reflects a redistribution of growth that would have occurred elsewhere in the metropolitan area. According to the hypothesis, highways often do not generate increases in economic activity but largely shift activity from one location to another. Sales-price data from commercial and office properties near two new southern California highways will be used to identify places that experienced economic gains and those that suffered economic losses. Then, this project will explore rationales for excluding economic effects from cost-benefit analyses of highway projects. In particular, the researcher will show that projects using state or federal funds should not claim economic gains if those gains may be offset by economic losses within the same funding jurisdiction.

The Environmental Quality of Multiple-Roadway Boulevards
Peter Bosselmann, City and Regional Planning, Berkeley
Allan Jacobs, City and Regional Planning, Berkeley

This research will examine resident satisfaction and livability associated with multiple-roadway boulevards. The research methods and experiments planned for this study are modeled after Donald Appleyard's famous 1972 study on the environmental quality of city streets. Here, the street-environment satisfaction level of residents living on multiple-roadway boulevards will be compared with that of residents living on "control" streets with similarly high-traffic volumes in the vicinity of the boulevards. Two of the boulevards chosen for this study are located in California, Chico and Fremont, and serve low-density suburban residential populations. Two are located in New York City and serve medium to high residential density districts. This study will build upon recently completed traffic safety and behavior research related to selected boulevards in Europe and the U.S.

Energy and Environmental Effects of Hybrid Electric Vehicles
Andrew F. Burke, Institute of Transportation Studies, Davis
Marshall Miller, Institute of Transportation Studies, Davis

Hybrid electric transit and private vehicles can be designed and operated to either minimize annual emissions or to maximize fuel economy. It is difficult to do both. The California Air Resources Board favors hybrids that minimize emissions. The NGPV program with the U.S. Big Three automakers intends to maximize fuel economy. This research will investigate the tradeoffs between emissions and fuel economy for both series and parallel hybrid vehicles using advanced energy storage components (high energy density batteries, pulse-power batteries, ultracapacitors, and flywheels) and highlight the effects of energy-control strategies and vehicle use patterns on these tradeoffs. Current controversies concerning the energy and environmental effects of hybrid vehicles relative to electric and internal combustion engine vehicles will be identified and clarified using detailed simulation results for a variety of hybrid vehicle designs, operating strategies, and use-patterns. The research will also investigate how the evolving gasoline-engine-electric hybrids considered in this study may lead to fuel-cell-powered hybrid vehicles in the future.

Assessing the Dynamics of Freeway Traffic
Michael J. Cassidy, Civil and Environmental Engineering, Berkeley

This research will investigate freeway dynamics by empirically evaluating how traffic disturbances propagate in time and space. The researchers have already developed a unique method to examine freeway flow dynamics using cumulative vehicle arrival curves constructed in series. This method facilitates freeway assessment in much greater detail than other methods allow. Using an extensive database, this study will categorize observed traffic phenomena and identify underlying cause and effect relationships. This research will advance the traffic engineering and planning professions by informing traffic analysts about the researchers' methodology and by providing a verifiable foundation for mathematical models of freeway traffic flow.

Influence of Mixed Land Uses on Travel Behavior
Robert Cervero, City and Regional Planning, Berkeley

This research will investigate how mixed land uses in predominantly residential settings influence trip generation rates, modal splits, and trip distances. Analyses will concentrate on shopping and nonwork trip-making. It is hypothesized that mixed uses exert their biggest influence on nonwork, internal trips. These should substitute transit trips for external, automobile trips, leading to lower VMT per capita. Matched pair comparisons will be made on travel characteristics of mixed- and single-use neighborhoods, controlling for household incomes, proximity, transit service levels, and density. A gravity-based model will also be estimated to weigh the importance of mixed uses in the attractiveness of internal versus external destinations, adjusting for proximity. Data from metropolitan Chicago and the San Francisco Bay Area will be used. Research results will provide guidance on how trip generation estimates may be adjusted to account for the effects of land use mixture.

Market Opportunities and Barriers to Expanded Paratransit Services
Robert Cervero, City and Regional Planning, Berkeley
Michael Bernick, Institute of Urban and Regional Development

This project will analyze the market potential of paratransit services (such as jitneys, shared-ride taxis, and commercial vans) to supply attractive transportation alternatives to private automobiles in California. The study will concentrate on the following areas: (1) defining the cost, service quality, and market demand for paratransit services in the U.S. and abroad; (2) identifying regulatory and institutional barriers, included government restrictions on market entry, to expanded paratransit services; (3) assessing the market potential for smart paratransit systems involving ATMS/ATIS technologies and jitney-van services in large urban centers, using both economic evaluations and informant interviews; and (4) outlining the parameters of a pilot program on the feasibility of smart paratransit and investigating possible sites for field studies.

Subcontracting for Transit Services
Linda Cohen, Economics, Irvine

This project will study contracting practices in the public bus industry based on service costs, contract provisions, and bus market characteristics. The researcher will test hypotheses on the conditions necessary for efficient contracts and for agencies to take advantage of contracting opportunities. The research initially will use Section 15 data for 1992, plus information from California, Arizona, Colorado, and Texas. This project will be the first year of a multiyear project on contracting practices at different U.S. bus agencies.

Market Value of Transportation Benefits Under Alternative Financing Schemes
Randall Crane, Urban and Regional Planning, Irvine

Land-price differentials have long been used as a proxy for the value of transportation improvements in cost-benefit analyses. But both empirical and theoretical literatures largely ignore two important facts: (1) taxes financing local improvements are often distorted; and (2) improvements that influence property values consequently affect the fiscal budget, tax rate, and final economic burden. This means that the true economic cost of an improvement is endogenous to both the transportation benefit and the revenue structure. This research will evaluate the accuracy of land-rent measures on the willingness to pay for improved access financed by either benefit taxes, property taxes (excise taxes), or highway tolls (user fees). Research results will be used to correct conventional empirical property value regression models that do not account for tax revenue effects or the excess burden of taxes.

BART at Twenty
Elizabeth E. Deakin, City and Regional Planning, Berkeley
Robert Cervero, City and Regional Planning, Berkeley
John Landis, City and Regional Planning, Berkeley

The Bay Area Rapid Transit System (BART) is now twenty years old and it's time to redo the BART Impact Studies of the mid-seventies. Accordingly, the Federal Transit Administration and Caltrans are sponsoring a joint project to expose the outcomes of BART's operations. The studies will examine BART's patronage trends, its effects on regional travel and land use patterns, its institutional settings within Bay Area government and politics, and its finances. This retrospective project will consider both BART's and the region's recent histories in an effort to understand their mutual influences.

Measuring the Effects of Transit-Linked Land Development on VMT
Elizabeth E. Deakin, City and Regional Planning, Berkeley
Charles Lave, Economics, Irvine

This study will empirically assess the reduction in personal VMT caused by transit-linked land development or by increased density or mixed-use zoning. The researchers will use a unique source of VMT data: objectively measured travel information at the zip code level of disaggregation. Research results will provide quantitative estimates of the extent that VMT is reduced by improved transit access or by urban form. Further, the new database produced in this study will be a general resource for Caltrans planning activities and other research.

Full Costs of Transportation: Motor Vehicles and Public Transit
Mark A. Delucci, Transportation Studies, Davis

The problems caused by petroleum-fueled passenger vehicles-air pollution, dependence on imported oil, global warming, and highway congestion-have prompted a growing number of researchers and policymakers to seek transportation alternatives. These alternatives include new fuels, new vehicles, new vehicle-highway systems, and public transit. From an economic perspective, policymakers should push the market to adopt transportation options with the minimal costs compared with benefits. This research aims to estimate the full costs (including private user costs, environmental costs, accident costs, parking costs, and the costs of importing energy, among others) of motor-vehicle and public transit modes. Besides evaluating the costs of gasoline-fueled passenger vehicles, this study will consider the following fuels and modes: methanol, compressed or liquefied natural gas, hydrogen, battery- or fuel-powered electric vehicles, buses, and light- and heavy-rail trains.

The Century Freeway's Effects on Nucleation, Land Use, and Travel Behavior
Joseph DiMento, Urban and Regional Planning, Irvine

Research on travel behavior concludes that factors affecting demand for urban travel include the location and intensity of land use, the socioeconomic characteristics of local residents, and the extent, cost, and quality of available transportation services. This research will use a case study, the Century Freeway/Transitway Corridor, to investigate the relationships among these factors. The 17.2 mile Century project includes six lanes for general traffic, two HOV lanes, the Green Lane (a light rail project with ten transit stations and park and ride lots), and ten local interchanges. This project will analyze transportation behavior and attitudes before and after the opening of the Century Freeway/Transitway, focusing on how land use changes around transit nodes affect modal choice and trip distribution.

Transit Bus Maintenance: Methods to Analyze Performance
G.J. Fielding, Economics, Irvine

This project will develop procedures to assist managers in evaluating how different inputs affect the cost and reliability of transit service. This project will analyze Section 15 data from 1985-1991 using a variety of measuring instruments including the following: ratio measures, total factor productivity, stochastic frontier analysis, and data envelopment analysis. The purpose is to determine which method is best for analyzing factors that affect bus maintenance.

Measurements of Motor Vehicle Cold-Start Emissions
Robert Harley, Civil and Environmental Engineering, Berkeley

This project will undertake to quantify cold-start emissions by testing cars that have been parked in public garages. Excess emissions occur during the first one to two minutes of vehicle operation because emission control equipment must warm up to function effectively. In morning (warmed up) and afternoon (cold start) sampling periods, researchers will measure carbon monoxide, carbon dioxide, nitrogen oxides, and speciated hydrocarbon concentrations. The significance of cold start emissions may be overstated in current computer model predictions. Understanding cold start emissions will help assess the impact of facilities such as transit park and ride lots.

Advanced Public Transit Systems Planning
R. Jayakrishnan, Civil and Environmental Engineering, Irvine
M.G. McNally, Civil and Environmental Engineering, Irvine

This study will implement the theoretical and analytical models developed during the first-year project, "APTS Planning: Transit Assignment and Implications of Route Choice." To create a useful framework, research will include the following areas: modifications to study various information supply schemes, conversion programs to use existing transportation planning packages, programs that correct defects in those planning packages, and guidelines to use the framework for design exercises. The Irvine city portion of the Orange County Transit Authority (OCTA) bus network will provide a case study.

Improving Transit-Oriented Land Development
Robert A. Johnston, Environmental Studies, Davis

Regional transportation agencies in California make two main types of investments in their plans: new HOV lanes and expanded transit, including rail modes. To make transit more productive, agencies advocate land use intensification; to make access to transit easier, they are studying pedestrian-friendly urban designs. This project will evaluate the relationships between zonal and discrete land use characteristics and household transit ridership in the Sacramento region. It will test a variety of models on the 1991 household travel survey and land use data sets for the region. Further, it will test for sample bias and other survey problems.

Strategic Planning Method for Regional Transportation and Land Use
Robert A. Johnston, Environmental Studies, Davis

This project will develop an integrated regional urban model, Tranus, based on data for the Sacramento region. The researcher has collected all necessary data and entered all coverages into the GIS-based California Urban Futures Model. Further study will resolve theoretical issues, improve contingency plans, and yield a refined planning method that integrates regional transportation and land use variables.

Edge Transit: Decentralization and Competition in Transportation Services
Daniel B. Klein, Economics, Irvine

This project will explore the economic and political viability of decentralized, competitive transportation services. "Edge transit" refers to variants of urban transportation: paratransit, jitneys, downsized vehicles, open markets, shuttle services, "smart" technologies, and privatized systems. The researchers will study how a decentralized system may evolve, considering policy factors. Hypothesized advantages of edge transit include consumer responsiveness, flexibility, innovation, technological suppleness, cost-effectiveness, and safety. Potential disadvantages include lack of coordination, irregularity of service, collusion, accidents, failure to exploit scale- and network-economies, and problems in designing a legal framework. The researchers will use Orange County as a case study.

Revising the California Urban Futures Model
John D. Landis, City and Regional Planning, Berkeley

This project will revise the California Urban Futures Model (CUF Model) specifically for the fourteen-county San Francisco Bay-Sacramento region. The researchers will develop the following models: (1) a model to explain past rates and allocations of employment growth; (2) a model that assesses demand for housing based on tenure type (rental or owner) and structure type; (3) a model that determines annual city-average housing prices and rents; and (4) a model based on the above three to evaluate the profitability of potential development sites depending on type of use. Further, the researchers will use the revised CUF Model to test how various regional transportation investments, such as highway expansion and transit construction, would influence land use patterns in the San Francisco Bay-Sacramento region.

Station Profiles and Development Potential of the Blue Line Corridor
Anastasia Loukaitou-Sideris, Urban Planning, Los Angeles
Tridib Banerjee, Urban and Regional Planning, University of Southern California

This project will examine whether transit can stimulate development in depressed urban areas, which in turn would increase both transit effectiveness and ridership. The researchers will study the real and perceived barriers to growth around station areas and the functions of public, private, and nonprofit sectors in stimulating that growth. The study will construct a station typology and evaluate economic development strategies and urban design guidelines for each station type.

Travel Characteristics in Alternative Land Development and Network Structures
Michael G. McNally, Civil and Environmental Engineering, Irvine

This research will apply an activity-based approach to investigate fundamental characteristics of travel behavior. It integrates household activities, land use distributions, regional demographics, and transportation networks in a framework that acknowledges the complex interactions among these factors. The research will use two extensive databases: (1) the Orange County database that comprises conventional trip diaries and GIS-based land use and transportation data; and (2) the Portland, Oregon, database that comprises two-day activity diaries and an extensive supporting activity database. Researchers will extend preliminary work with the Orange County data and investigate the Portland data, generate and classify activity patterns for both data sets, and compare the effects of external factors on travel behavior in each.

Behavioral Adjustments to Congestion
Patricia L. Mokhtarian, Civil and Environmental Engineering, Davis
Ilan Salomon, Institute of Transportation Studies, Davis

While congestion is a major concern for both citizens and policymakers, their perceptions of causes and potential solutions differ greatly. This study will evaluate commuters' responses to congestion, including their adoption or rejection of various policies. Potential responses to congestion will vary in time frame, generalized implementation costs, and distributional impact. Using data previously collected from a 628-person sample, the researchers will test the hypothesis that responses correlate with previously adopted adjustments, and that the efficacy of congestion-reduction policies differ across socioeconomic classes. Understanding the dynamics of the coping process is important because policy measures directed at groups that have already exhausted the benefits of those measures may be futile.

Fixed Route and Paratransit Services: A Comparison of Accessibility
Debbie Niemeier, Civil and Environmental Engineering, Davis

The Americans with Disabilities Act (ADA) allows transit authorities to charge twice the base fare of comparable fixed-route services. Further, Section 5(m) of the Federal Transit Act requires fixed-route services to charge half fares for the elderly and disabled during off-peak periods. These are fare differentials for essentially the same length trip. Therefore, fixed-route patrons may pay only 25 percent of a paratransit patron's fare when they travel to the same destination. But the accessibility provided by paratransit service may actually be "worth" more than that provided by comparable fixed-route service. This study will extend previous research on price and demand elasticity and will compare the value of paratransit access with that of fixed-route access for the elderly and disabled. The researcher will use new survey data and a logit-model formulation.

Effects of Transportation Policies and Neighborhood Characteristics on Access
Wilfred Recker, Civil and Environmental Engineering, Irvine
Tom Golob, Institute of Transportation Studies, Irvine

A previous UCTC study used generic algorithms to analyze and predict the optimal path of household members through time and space. The study uses a model that removes existing barriers, thereby making it possible to analyze travel behavior using activity-based approaches. The next step is to incorporate a behavioral structure into a mathematical procedure that optimizes household activity/travel paths, which applies to policy-sensitive travel demand situations. The research will use new travel/activity data from Portland, Oregon, which demonstrates the effects of transportation policy and neighborhood characteristics on accessibility. The researchers will develop a comprehensive framework to study travel options such as activity substitution, carpooling, and trip chaining.

Emissions from Current and Reformulated Gasoline
David M. Rocke, Management, Davis

Transit and highway planning strategy must conform to environmental goals and regulations. While there are many long-term strategies for reducing the environmental costs of transportation, short-term strategies are more limited. One short-term strategy adopted by both federal and state governments is the mandatory use of reformulated gasoline as an automotive fuel. Along with the California Air Resources Board (CARB), the researcher has constructed predictive models of mass emissions of NOx, CO, and HC that were included in the June 1994 CARB regulations. Improved models will include technical innovations and information on the interaction between vehicle and fuel characteristics, and on the behavior of oxygenation. This project will address policies to reduce the environmental costs of automotive transportation.

Three Puzzles in Vehicular Pollution Control
Paul Sabatier, Environmental Studies, Davis

This study will complete a two-year-old project that applies policy process theories to understand three puzzles that have plagued U.S. vehicular air pollution policy: (1) why there is great variation in the quality of inspection and maintenance programs among states; (2) whether coalitions in federal pollution control have been relatively stable over time or whether there have been a series of "minimum winning coalitions"; and (3) who have supported various measures to reduce VMT since 1960 and why Congress adopted the "consistency" provisions in the 1990 Clean Air Act after years of rebuffing effective TCM measures. The researchers will review the various theories that presently guide transportation planners and develop tools for internalizing the external costs of the current transportation system.

Cruising for Parking
Donald C. Shoup, Urban Planning, Los Angeles

When the price of curb parking is less than the price of adjacent off-street parking, motorists have an incentive to cruise in search of vacant curb space instead of paying for higher-priced off-street parking. The researcher has developed a model of this choice to cruise, and has formed various predictions, for example, solo drivers will cruise longer than carpools. Using aerial videotapes of traffic and parking in Westwood, the researcher will examine the cruising behavior of all motorists who parked at curbside and in off-street lots. Further, he will compare the motorists' videotaped behavior with survey responses they made after being videotaped. This study will test the economic model of cruising.

A Modal Emissions Model for Environmental Impact Assessment
Daniel Sperling, Civil and Environmental Engineering, Davis
Troy Young, Civil and Environmental Engineering, Davis

Current emissions models have significant shortcomings, including the inability to reflect variation in emission rates caused by changes in acceleration, deceleration, cruise, and idle modes. This research will seek to overcome these shortcomings and to develop statistical emissions models for HC, NOx, and CO2 that can predict vehicle exhaust emissions under the full range of modal activities. The models will complement the latest modal CO emission model and facilitate integration with traffic simulation models and regional models. Since planners must comply with National Air Quality Standards within three years, there is a need for immediate air quality planning tools such as the models discussed above.

An Integrated Stated Preference Approach to Transportation Choices
Thomas Turrentine, Institute of Transportation Studies, Davis
Kenneth Kurani, Institute of Transportation Studies, Davis

Planners must consider consumer reaction to transportation initiatives designed to reduce car usage. However, current methods fail to accurately judge consumer responses to the complex interplay of new technologies, control measures, and planning. This project will develop Interactive Stated Preference (ISP) techniques to explore consumer responses to different transportation alternatives. Research results will be used to develop new ISP methods for three alternative solution sets including small electric vehicles, walking and biking, and paratransit. The researchers will test these methods on a sample of California households.

Evaluation of the Foothill Transit District
Martin Wachs, Urban Planning, Los Angeles
Brian D. Taylor, Urban Planning, Los Angeles

This project will evaluate the Foothill Transit District, which serves a 327 square mile area including the San Gabriel and Pomona Valleys in eastern Los Angeles County. The District is unique among transit operators because it has no employees; instead, it contracts all of its services. The researchers will measure the Foothill Transit District's effectiveness by comparing the District with other operators and by assessing its effects on the San Gabriel and Pomona Valley economies.

Indicators of Transit Effectiveness in California
Martin Wachs, Urban Planning, Los Angeles

Managing and evaluating transit systems in California have become more complex as the number of transit modes have increased. Although policy makers and transportation planners must make choices in allocating funds among transit options, there is no methodology for measuring and comparing the effectiveness of transit systems including multiple modes. This project will evaluate current indicators of transit performance in California and identify the promising ones for use in multimodal transit systems nationwide. By documenting and disseminating a model for applying performance indicators to multimodal transit systems, this research will immediately help transit professionals. Further, by comparing the performance of different transit modes, policy makers will be able to determine which transit modes are most effective.

Dissertation Research

New Horizons in Incident-Detection Algorithms
Baher Abdulhai, Civil and Environmental Engineering, Irvine

Nonrecurring freeway congestion due to incidents is a major cause of overall congestion. Artificial Neural Networks are the best way to detect such incidents. In the past, one network, the Multilayer Feed Forward (MLF), outperformed the others. Using both advanced technology and existing statistical theories, the researcher will seek to develop even better algorithms for freeway incident detection. Further, this project will determine whether the performance of a given algorithm can be controlled, based on where it is implemented. The researcher will use previously unavailable traffic and incident data collected from major freeways nationwide.

Demand for Alternative Fuel Vehicles by Commercial and Bus Fleets
Soheila Soltani Crane, Economics, Irvine

A major source of urban air pollution is tailpipe emissions from gasoline-fueled vehicles. A new transportation system based on alternative fuel vehicles (AFVs) may be the means to reduce this pollution, conserve petroleum, and still maintain mobility. While commercial fleets are considered to be the first likely AFV users, most studies on AFV demand have concentrated on household demand. This project will examine commercial fleet demand for the three major types of AFVs: electric, compressed natural gas, and methanol vehicles. The researcher will construct a dynamic fleet vehicle transaction model that can predict the type of vehicle that commercial and local government sectors will purchase and the timing of those purchases.

Revealed Behavior and Stated Intentions for Vehicle Transactions Noah Yong E. Kim, Economics, Davis

To predict how consumers will respond to new transportation alternatives, planners may use models based on stated-preference (SP) survey questions about hypothetical choices. But many researchers prefer observed revealed-preference (RP) data, which may be more accurate. Using detailed SP and RP data on vehicle transactions regarding alternative fuel vehicles, the researcher will perform external validity studies on SP, RP, and SP/RP models and develop and test theories that explain differences between SP and RP data.

Development of Dynamic Vehicle Transactions Models
Raghu R. Kowshik, Civil and Environmental Engineering, Davis

This project will develop dynamic vehicle transaction models using competing risk and event history models. The models created will improve the travel demand forecasting process using microsimulation. The new continuous-time models should be significantly better than existing discrete-time, discrete-choice models of vehicle ownership. Further, this research will consider the vehicle ownership decisions of households with more than two vehicles.

State Apportionment Policies for Transportation Funding
Lewison Lee Lem, Urban Planning, Los Angeles

Current research on intergovernmental grants for public transit assistance has found significant inequity in the geographical distribution of public funding. This project will evaluate the equity of apportionment policies for all transportation spending at the state level, and will recommend improvements to existing apportionment systems nationwide. The researcher will evaluate the effects of state funding for roads and highways, rail transit, and other public transportation. This evaluation will help identify apportionment variables and formulas that can increase the equity of funding distributions. Analyzing the legislative histories of the most equitable apportionment systems will help improve transportation fund apportionment in all states.

Electric Vehicle Costs, Technologies, and Policies
Timothy E. Lipman, Environmental Studies, Davis

The potential costs of mass-producing advanced electric vehicles (EVs) remain uncertain. This study will investigate those potential costs by constructing a model that estimates potential cost reductions that may occur with industrial "learning" and diffusion of innovations. The research will draw upon a wide range of disciplines-including economics, policy analysis, engineering, and sociology-and will explore the policy implications of present and future costs.

The Value of Information for Departure Time Decisions
Rosella Picado, Civil and Environmental Engineering, Berkeley

This project will determine the value of information in travelers' departure time decisions. The value of information for a single driver is the difference between having only previous knowledge (prior analysis) and having more recent knowledge (posterior analysis) about a situation. The researcher will evaluate the value of information at both the private and system levels, using a Bayesian framework, and will consider the following variables: the heterogeneity of drivers, lateness penalties, and the number of drivers with access to information.

Generation of Dynamic Trip Tables
Ruey-Min Wang, Civil and Environmental Engineering, Irvine

The researcher will develop a microsimulation model for disaggregate activity-based travel demand forecasting that integrates household activities, land use distributions, and regional demographics in an explicitly time-dependent fashion. This model will allow dynamic simulation of the effects of air quality, network mobility, and land use policies, thereby surpassing the flexibility, sensitivity, and transferability of conventional planning models. In the short term, this research will create a method for forecasting dynamic, linked-trip, origin-destination demand matrices. In the long term, this research will contribute to the development of alternative transportation planning methods.

Paratransit Operations at United States Airports
Rachel Weinberger, City and Regional Planning, Berkeley

This project examines shared-ride van services that provide airport access at five U.S. airports. Consumers seem to favor airport access paratransit modes, but evidence indicates that the operators are often financial losers. If paratransit cannot succeed in this market, its prospects for broader applications are questionable. To address these concerns, the researcher will create a framework to explain why paratransit succeeds or fails by reconciling relevant economic, infrastructure, and social policy issues. The researcher will consider labor issues, competition with other ground transportation modes, qualitative differences in airport access services, and the operating and economic factors that affect competition among paratransit operators.

Controlling Recurrent Saturated Demands in Dense Activity Centers
Wann-Ming Wey, Civil and Environmental Engineering, Irvine

This project will develop control techniques to mitigate congestion problems in high density traffic networks. The techniques will aim at reducing the queues and delays in oversaturated conditions instead of providing conventional "progressive movement," such as stop-line detectors that do not provide enough information in oversaturated conditions. The research will focus on adapting strategies for signalized arterials to produce real time control strategies that deal with gridlock. Further, the study will seek to develop measures of effectiveness (vehicle delay, travel time, queue length, etc.) that can be compared with those of current strategies.