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| Current Research Projects |
| Handheld Travel Survey Technology to Supplement Vehicle Tracking in a Shared-use Station Car Program (2002) | [ back to top ] |
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Investigator: Michael G. McNally Support: U.S. Department of Transportation and California Department of Transportation via UCTC Summary: An experimental shared-use station car program using electric vehicles is being implemented in association with several public and private sector organizations in Irvine, CA. The goal of this program is to demonstrate the potential of linking shared-use electric vehicles with conventional line-haul public transit services to provide automobile-like accessibility at the ends of the commute trip. The decision to travel with the shared-use vehicles can be understood only through examining the process of how participants schedule activities before and after shared-use vehicles become a travel option. To address this need, GPS-based in-vehicle tracking technologies are being utilized with web-based travel surveys. It is proposed to supplement this survey approach with a GPS-based handheld device to track travel and activity when not using program vehicles. The handheld device continuously records and stores spatial position, dumping this data via a wireless link to the in-vehicle device when completing activities. In conjunction with current program technologies and as a stand-alone technology, the handheld technology will be assessed relative to its efficacy in the acquisition of comprehensive data on daily travel and activities, while minimizing user effort and inconvenience. These devices will also be evaluated as a means of providing remote access to reservation systems and as keyless access to program vehicles. | |
| Paramics Support for Transportation Planning (2002) | [ back to top ] |
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Investigator: Michael G. McNally and
Will Recker Support: California Department of Transportation (Caltrans) via PATH TO 4320 Summary: As Caltrans begins to integrate microsimulation models with conventional travel forecasting models, critical issues must be resolved and a variety of anticipated problems resolved. Work tasks include providing On-call API Support, including supporting Caltrans user inquiries on currently implemented UCI-developed APIs and providing API maintenance, enhancement, and development; providing Technical Guidance on Microsimulation, including microsimulation modeling guidance and evaluation, and peer review of Caltrans microsimulation model guidelines; and providing Research-related Support on the interface between the 4-step model and traffic microsimulation models, and on the evaluation of validation and calibration techniques for microsimulation. | |
| Activity-based Modeling in the Wireless Information Age (2002) | [ back to top ] |
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Investigator: James Marca Support: University of California Transportation Center (UCTC) Summary: One of the main barriers to a better understanding of activities and travel patterns is the difficulty in collecting long-duration data. Previous studies have examined computer-aided interview techniques. Others have researched the potential for global positioning system (GPS) antennas to collect more accurate travel data. This dissertation adds the use of wireless communications technology to integrate GPS data with a dynamically generated, web-based activity survey. In addition, three separate analysis techniques are examined using the results of an informal pilot test. The goal of these analysis techniques is to weave together the large set of GPS data that can be collected with the much smaller set of activity responses. The net result represents both an advance in data collection techniques, as well as a new, peer-to-peer approach to gathering and sharing experiential transportation information, an approach that should be incorporated into future Intelligent Transportation Systems designs. | |
| Methodological Implications of Human Activity System Complexity for Travel Demand Forecasting (2002) | [ back to top ] |
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Investigator: Craig Rindt Support: University of California Transportation Center (UCTC) Summary: The Holy Grail of activity analysis is a "grand unified theory" that successfully relates motivation and constraint to pattern. This research is motivated by this search and adopts the premise that such a unified theory requires a focus on causal theories as much as it requires analytical characterizations of empirical data. Capturing complex networks of causation in the system requires a model that is based less on analytical characterizations of the world (constraint vs. pattern) and instead focuses on direct descriptions of the features of the world that produce the patterns we observe. In other words, models should represent the mechanisms of constraint and pattern and not use these concepts as building blocks for theory. --- more --- | |
| Applications of Traffic Microsimulation to Transportation Planning (2002) | [ back to top ] |
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Investigator: Michael G. McNally and
Will Recker Support: University of California Transportation Center (UCTC) Summary: UCI has developed considerable expertise in the development and application of microsimulation models, and has worked closely with PATH, Caltrans, FHWA, and other agencies in a variety of primarily traffic applications. Spurred by policy needs and the availability of commercial microsimulation models, planners and engineers who deal with conventional transportation forecasting models have expressed an interest is investigating the application of microsimulation models, in general, and in conjunction with conventional model systems, in particular. Caltrans has requested Irvine faculty to provide an overview of microsimulation capabilities to Caltrans planners and engineers. Material for a 1-day microsimulation workshop for Caltrans planners and engineers will be developed. The workshop will provide an overview of available software packages, case studies of applications, issues of coordination with conventional travel forecasting models, and demonstrations. A user-oriented focus rather than a decision-maker orientation is defined. Workshop material will be defined in a modular format to allow for variations in presentation for subsequent offerings. | |
| ZEVNET - A Shared-use Station Car Project (2001) | [ back to top ] |
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Investigator: Michael G. McNally,
Will Recker, and
Scott Samuelson Support: Toyota Motor Corporation Summary: The National Fuel Cell Research Center (NFCRC) and the Institute of Transportation Studies (ITS) at the University of California, Irvine have entered Phase 2 of a three phase program investigating the feasibility of deploying city electric vehicles in shared-use and station car modes within a corporate management structure. This program is the subject of the research, development, and evaluation effort currently underway. This effort initially focuses on the implementation of novel survey systems in each ZEVNET vehicle to track vehicle trajectories and to subsequently survey individual drivers, and their households, relative to their use of the cars and the associated impact on household travel behavior. The project objective is to determine whether such a program can reduce the traffic and environmental impacts of the automobile-dominated transportation system and help to achieve the goals of California's ZEV mandate? | |
| Activity-Based Forecasting Model for Planning Applications (2001) | [ back to top ] |
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Investigator: Will Recker Support: U.S. Department of Transportation and California Department of Transportation via UCTC Summary: The work proposed here will be based on previous activity-based research conducted by the principal investigator and his colleagues and will be directed toward developing a practical planning application of a mathematical programming activity-based model as an effective travel demand forecasting tool. In the proposed research, we seek to complete the modeling framework that has evolved over past research efforts by extending it to a "traditional" planning framework. Specifically, we will couch the activity-based approach in terms that are amenable to its development as a planning tool for travel demand forecasting that not only provides output consistent with accepted trip-based static planning methodologies, but further provides full estimates of the associated dynamics of trip generation, distribution and route selection; all from a theoretically consistent paradigm based on the need/desire of households to interact with their environment. By showing that the particular mathematical programming paradigm can be used to describe the demand modeling processes both for conventional trip-based travel demand and for activity- based approaches it is hoped not only to facilitate the practicality of activity-based modeling approaches, but also to tap into the wealth of research that has guided mainstream travel demand analysis. If successful, the research will produce the first known activity-based model framework that can be applied to empirical demand forecasting - an application that has long eluded activity-based modeling proponents. | |
| Assessing the Influence of Residential Location Changes on Travel Behavior (2001) | [ back to top ] |
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Investigator: Michael G. McNally Support: U.S. Department of Transportation and California Department of Transportation via UCTC Summary: There are certain fundamental transportation problems that have remained problems, in part, due to an inability to effectively collect the data necessary to address the problem. One such problem involves the "learning" process by which a household re-locating into a new neighborhood evolves new household activity patterns. More specifically, when a household relocates, what are the immediate and longer term impacts on travel behavior of the local activity and transportation systems? How do household travel patterns evolve? While simple logic suggests that new alternatives will be available for travel and activity decision-making, what are these choices and how does knowledge of these choices evolve. This project proposes to use technologies developed in prior UCTC, PATH, and Testbed research projects to facilitate the observation of a small number of households re-locating from other areas in Orange County, CA to selected new home developments in Irvine. We will install in-vehicle GPS/Wireless Communication units in all household vehicles to measure specific vehicle use for a multi-day period prior to moving, upon re-locating, and a few months after relocating to Irvine. We will also have the sampled households use REACT!, an computer-based survey research software developed in prior UCTC research, to record their household activities during this same period. We will utilize GIS-based data sets depicting both the local activity-systems and transport networks. Together, this data will enable us to address the immediate changes in travel behavior upon relocation, and to assess the evolution of stability in this behavior over time. | |
| Considering Risk-Taking Behavior in Travel Time Reliablity (2001) | [ back to top ] |
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Investigator: Will Recker Support: California Department of Transportation, Partners for Advanced Transit and Highways (PATH) Summary: Despite the importance of assessing the reliability of road networks, there exist only a few suitable techniques. The approaches used in water supply systems, communication systems, and power transmission systems are not directly applicable for transportation systems. The reason is that these approaches ignore route choice behavior when evaluating the performance reliability of a network. This research proposes to incorporate a risk-taking, route choice behavior when estimating travel time reliability of a road network. The proposed research approach will allow the evaluation of network performance under uncertainty. It is particularly useful for the traffic information systems in which travel time information (not only the mean travel time but also the variance of travel time) is provided to the network users for decision-making. It is anticipated that the proposed research can also be used to evaluate the performance of the Advanced Traveler Information Systems (ATIS) and to improve the level-of-service of a road network. A significant part of this project focuses on developing realistic route choice models by incorporating both the traveler's imperfect knowledge of network travel times as well as the variability of these travel times. Since the route choice problem and the origin-destination (OD) estimation problem are inter-dependent (i.e., the input of one problem is the output of the other problem), this project is also expected to contribute to improving the accuracy and reliability of the OD estimation problem. Though the OD estimation problem is not explicitly addressed in this proposal, the development of realistic route choice models is a key factor in the investigation of origin-destination demand procedures. In addition, it is possible to assess the quality of the estimated OD demand using the variance-covariance matrices of the link choice proportions resulted from the proposed route choice models since uncertainties associated with supply and demand variations are explicitly captured in the models. | |
| Micro-Simulation Traffic Model Implementation (2000) | [ back to top ] |
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Investigator: Michael G. McNally Support: Orange County Transporation Authority Summary: The OCTA RFP summarizes the state-of-the-practice for macro-simulation modeling in Orange County. The Orange County Transportation Authority (Authority) is responsible for transportation modeling in Orange County. The current Orange County Transportation Analysis model (OCTAM) has been recently updated to OCTAM 3.0 for Base Year 1998 and further improvements are on-going. OCTAM 3.0 incorporates state-of-the-practice modeling components that are consistent with the new Southern California Regional Transportation Model recently released by the Southern California Association of Governments (SCAG). The OCTAM 3.0 model provides a regional travel forecasting base for transportation planning work in Orange County. The OCTAM model is regional in nature and suited for macro-level analysis. This proposal offers professional services, which are required to assist the regional modeling section in evaluating and integrating a traffic micro-simulation model. The purpose of integrating a micro-simulation with the macro-simulation OCT AM model is to allow a more detailed evaluation of projects through the analysis of various measures of effectiveness. OCTA has identified candidate projects for the application of the micro- simulation model, including network infrastructure improvements such as gap closures, arterial widening, and the addition of HOV or general purpose lanes, as well as operational enhancements such as grade separation of rail, freeway auxiliary lane addition, ramp metering, one-way couplets, reversible lanes, reconfiguration of interchanges, smart streets, and the identification of specific locations to target for improvements such as arterial or freeway bottlenecks. | |
| Assessment of the Potential of Trip Chaining, Ridesharing and Carpooling Mandates to Reduce Energy Consumption and Vehicle Emissions (2000) | [ back to top ] |
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Investigator: Will Recker Support: U.S. Department of Transportation and California Department of Transportation via UCTC Summary: The 1990 Clean Air Act Amendments (CAAA) and 1991 Intermodal Surface Transportation Efficiency Act (ISTEA) have defined a broad range of transportation control measures (TCMs) to mitigate the negative energy and emissions effects of increased travel. These measures include alternatives to single-occupant travel and reduction of travel through substitution or more efficient chaining of trips. Yet is not clear how these measures will change travel behavior, how these changes will impact environmental goals and whether or not these policies will disproportionately impact certain household members or segments of society. Building upon previous research in activity-based behavioral analysis, this project uses empirical travel/activity behavior linked with a geographic information system (GIS) to assess impacts of TCMs on energy consumption, vehicle emissions and mobility/accessibility. | |
| GPS/GIS Technologies for Traffic Surveillance and Management (2000) | [ back to top ] |
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Investigator: Michael G. McNally Support: California PATH and ATMS Testbed Summary: Despite the advances in Intelligent Transportation System (ITS) technologies, in particular in the Advanced Transportation Management and Information Systems (ATMIS) area, and the potential for improving transportation system performance, there is still at least one critical bottleneck which must be addressed prior to any real operational advances. The bottleneck limiting the effective applications of many ITS technologies is our limited understanding of the relationships between transportation system performance and characteristics of travel demand. While our models of supply tell us what we should do under various traffic scenarios, there is little that we may confidently implement due to a fundamental lack of understanding of individual travel demand and route utilization. Any attempt to implement traffic management strategies requires assuming a demand pattern -- one that we cannot subsequently modify based on the implemented modification to the supply. Even the real-time application of simple Advanced Transportation Management and Information Systems (ATMIS) strategies such as modification of signal timings is severely limited by the inability to generate real-time Origin-Destination (OD) matrices, let alone demand matrices that reflect modifications directly resulting from the implemented strategies. A 2-phase study is proposed. A preliminary study will evaluate the concept of vehicles as probes to gather basic link characteristics such as travel time and delay. This preliminary study will provide a field assessment of the proposed technologies and will contribute to the exploration of the primary research objectives relating to route choice behavior and improved prediction of travel demands for real-time traffic management. The proposed research seeks to gain better understanding of route choice behavior as part of individual travel patterns through the analysis of a sample of individual travel patterns. The second phase of the study is a full study of travel patterns which will be collected using a travel survey augmented with Global Positioning System (GPS) data. The integration of a GPS component into the survey instrument (funded separately and under current development) will allow for the analysis of observed travel demands and route choices versus the actual traffic conditions faced by the survey respondent. Real-time traffic condition data will be collected using existing ATMIS technologies that are already a part of the California ATMIS Testbed. This will enable a detailed picture of the demand for travel to be overlaid onto an equally detailed picture of the actual transportation supply levels. The combination of these two data sets will form a bridge across the existing gap in our knowledge of the relationship between transportation system performance and travel demand. | |
| Putting Behavior in Household Travel Behavior Data: An Interactive GIS-Based Survey via the Internet (2000) | [ back to top ] |
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Investigator: Michael G. McNally Support: U.S. Department of Transportation and California Department of Transportation via UCTC Summary: This project is the second phase of a planned two-year research effort. The primary goal of the research is a fundamental examination of the behavioral process that results in revealed travel behavior. To reveal this process, a computer-based household activity survey program, CHASE, has been re-programmed, enhanced, and extended for Internet application (REACT!), integrated with a GIS, and utilized in a pilot study to collect data for a study of the determinants of travel and activity behavior in households. These data are inherently dynamic, since CHASE respondents record planned activity agendas and then update and schedule these agenda, on a daily basis, fully defined in time and space (with REACT! recording the process of adding, modifying, and deleting components of a weekly travel pattern). The resultant data will facilitate the identification of fundamental inter-relationships among a comprehensive range of revealed travel and activity participation variables, leading toward the identification of what are the critical variables, relationships, and rules that govern that behavior. It is believed that an internet-based travel survey, particularly one as rich in resultant content as REACT!, will significant reduce data collection costs, improve data quality and quantity, and allow for continuous data collection. | |
| Putting Behavior in Household Travel Behavior Data: An Interactive GIS-Based Survey via the Internet (1999) | [ back to top ] |
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Investigator: Michael G. McNally and Sean Dougherty (Université Laval, Quebec City, Canada) Support: U.S. Department of Transportation and California Department of Transportation via UCTC Summary: This project examines the behavioral processes that result in revealed travel behavior. The research team uses a prototype computer-based household activity survey program that has been converted to JAVA and integrated with a geographic information system (GIS) for use on the Internet. Survey participants record planned activity agendas and then update and schedule them on a daily basis. The project also assess the feasibility of integrating global positioning system (GPS)-recorded routing data into the survey process. These findings help identify fundamental interrelationships among a range of revealed travel and activity participation variables; and enhance our understanding of the critical variables, relationships and rules that govern travel behavior. | |
| Development of Estimation Procedures for Activity-Based Model Forecasting (1999) | [ back to top ] |
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Investigator: Will Recker Support: U.S. Department of Transportation and California Department of Transportation via UCTC Summary: The work in this study is based on previous activity-based research conducted by the principal investigator and his colleagues and is directed toward developing a practical estimation procedure that will enable the use of a mathematical programming activity-based model as an effective demand forecasting tool. Although the modeling approach has been applied successfully to a number of transportation applications to explore issues relating to such areas as vehicle emissions, accessibility, trip-chaining, ridesharing and travel time reduction, in all of these applications the specification of the objective function is prescribed by the analyst; e.g., the minimization of emissions produced by travel. Conversely, the typical problem in demand modeling is focused on inferring the relative weights associated with potential components of the utility function that are determinants to a population's revealed selection of the decision variables. This particular aspect of the application of the activity-based research approach has remained a challenge. The activity-based modeling framework developed offers a real analytical option for estimating the relative importance of factors associated with the spatial and temporal interrelationships among the out-of-home activities that motivate a household's need or desire to travel. Demand estimation within the activity-based modeling framework is seen to provide both the necessary constraint considerations on the household's decision alternatives within a utility-maximizing structure as well as a convenient mechanism for generating the set of feasible alternatives that are likely to be considered. If successful, the research will produce the first known activity-based model framework that can be applied to empirical demand forecasting an application that has long eluded activity-based modeling proponents. | |
| Archival Project Summaries | [ back to top ] |
| Last revised: 04 August 2004 | [ ITS | Back to Top | UCI ] | http://www.its.uci.edu/ |