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Archives: Research Products
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Multilayered governance and infill development: Mobilizing community associations to promote sustainable land use and transport
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Phd Dissertation
Integration of Locational Decisions with the Household Activity Pattern Problem and Its Applications in Transportation Sustainability
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Abstract
This dissertation focuses on the integration of the Household Activity Pattern Problem (HAPP) with various locational decisions considering both supply and demand sides. We present several methods to merge these two distinct areas–transportation infrastructure and travel demand procedures–into an integrated framework that has been previously exogenously linked by feedback or equilibrium processes. From the demand side, travel demand for non-primary activities is derived from the destination choices that a traveler makes that minimizes travel disutility within the context of considerations of daily scheduling and routing. From the supply side, the network decisions are determined as an integral function of travel demand rather than a given fixed OD matrix. First, the Location Selection Problem for the Household Activity Pattern Problem (LSP-HAPP) is developed. LSP-HAPP extends the HAPP by adding the capability to make destination choices simultaneously with other travel decisions of household activity allocation, activity sequence, and departure time. Instead of giving a set of pre-fixed activity locations to visit, LSP-HAPP chooses the location for certain activity types given a set of candidate locations. A dynamic programming algorithm is adopted and further developed for LSP-HAPP in order to deal with the choices among a sizable number of candidate locations within the HAPP modeling structure. Potential applications of synthetic pattern generation based on LSP-HAPP formulation are also presented. Second, the Location – Household Activity Pattern Problem (Location-HAPP), a facility location problem with full-day scheduling and routing considerations is developed. This is in the category of Location-Routing Problems (LRPs), where the decisions of facility location models are influenced by possible vehicle routings. Location-HAPP takes the set covering model as a location strategy, and HAPP as the scheduling and routing tool. The proposed formulation isolates each vehicle’s routing problem from those of other vehicles and from the master set covering problem. A modified column generation that uses a search method to find a column with a negative reduced price is proposed. Third, the Network Design Problem is integrated with the Household Activity Pattern Problem (NDP-HAPP) as a bilevel optimization problem. The bilevel structure includes an upper level network design while the lower level includes a set of disaggregate household itinerary optimization problems, posed as HAPP or LSP-HAPP. The output of upper level NDP (level-of-service of the transportation network) becomes input data for the lower level HAPP that generates travel demand which becomes the input for the NDP. This is advantageous over the conventional NDP that outputs the best set of links to invest in, given an assumed OD matrix. Because the proposed NDP-HAPP can output the same best set of links, a new OD matrix and a detailed temporal distribution of activity participation and travel are created. A decomposed heuristic solution algorithm that represents each decision makers’ rationale shows optimality gaps of as much as 5% compared to exact solutions when tested with small examples. Utilizing the aforementioned models, two transportation sustainability studies are then conducted for the adoption of Alternative Fuel Vehicles (AFVs). The challenges in adopting AFVs are directly related to the transportation infrastructure problems since the initial AFV refueling locations will need to provide comparable convenient travel experience for the early adopters when compared to the already matured gasoline fuel based transportation infrastructure. This work demonstrates the significance of the integration between travel demand model and infrastructure problems, but also draws insightful policy measurements regarding AFV adoption. The first application study attempts to measure the household inconvenience level of operating AFVs. Two different scenarios are examined from two behavioral assumptions – keeping currently reported pattern and minimizing the inconvenience cost through HAPPR or HAPPC. From these patterns, the personal or household inconvenience level is derived as compared to the original pattern, providing quantified data on how the public sector would compensate for the increases in travel disutility to ultimately encourage the attractiveness of AFVs. From the supply side of the AFV infrastructure, Location-HAPP is applied to the incubation of the minimum refueling infrastructure required to support early adoption of Hydrogen Fuel Cell Vehicles (HFCVs). One of the early adoption communities targeted by auto manufacturers is chosen as the study area, and then three different values of accessibility are tested and measured in terms of tolerances to added travel time. Under optimal conditions, refueling trips are found to be toured with other activities. More importantly, there is evidence that excluding such vehicle-infrastructure interactions as well as routing and scheduling interactions can result in over-estimation of minimum facility requirement.
Suggested Citation
Jee Eun Kang (2013) Integration of Locational Decisions with the Household Activity Pattern Problem and Its Applications in Transportation Sustainability. Ph.D.. University of California, Irvine. Available at: https://uci.primo.exlibrisgroup.com/permalink/01CDL_IRV_INST/u4evf/cdi_bjzhongke_primary_AAI3592017 (Accessed: October 13, 2023).published journal article
Efficient Estimation of Nested Logit models
Journal of Business & Economic Statistics
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David Brownstone and Kenneth A. Small (1989) “Efficient Estimation of Nested Logit models”, Journal of Business & Economic Statistics, 7(1), pp. 67–74. Available at: 10.1080/07350015.1989.10509714.conference paper
Pseudorange measurement outlier detection for navigation with cellular signals. WIP abstract
Proceedings of the 10th ACM/IEEE international conference on cyber-physical systems
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Mahdi Maaref, Joe Khalife and Zaher M. Kassas (2019) “Pseudorange measurement outlier detection for navigation with cellular signals. WIP abstract”, in Proceedings of the 10th ACM/IEEE international conference on cyber-physical systems. ACM, pp. 346–347. Available at: 10.1145/3302509.3313334.research report
Assessment and Development of Commodity Flow, Logistics, and Other Relevant Goods Movement Data Sources to Facilitate Statewide Freight Modeling
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Stephen G. Ritchie, Shin-Ting Jeng, Andre Tok, Dmitri Arkhipov, Pedro Veiga De Camargo, Rex Chen, Joseph Y.J. Chow, Jae Young Jung, Fatemeh Ranaiefar and Miyuan Zhao (2010) Assessment and Development of Commodity Flow, Logistics, and Other Relevant Goods Movement Data Sources to Facilitate Statewide Freight Modeling. Research Report. ITS-Irvine.published journal article
Joint design of multimodal transit networks and shared autonomous mobility fleets
Transportation Research Part C: Emerging Technologies
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Providing quality transit service to travelers in low-density areas, particularly travelers without personal vehicles, is a constant challenge for transit agencies. The advent of fully-autonomous vehicles (AVs) and their inclusion in mobility service fleets may allow transit agencies to offer better service and/or reduce their own capital and operational costs. This study focuses on the problem of allocating resources between transit patterns and operating (or subsidizing) shared-use AV mobility services (SAMSs) in a large metropolitan area. To address this question, a joint transit network redesign and SAMS fleet size determination problem (JTNR-SFSDP) is introduced, and a bi-level mathematical programming formulation and solution approach are presented. The upper-level problem modifies a transit network frequency setting problem (TNFSP) formulation via incorporating SAMS fleet size as a decision variable and allowing the removal of bus routes. The lower-level problem consists of a dynamic combined mode choice-traveler assignment problem (DCMC-TAP) formulation. The heuristic solution procedure involves solving the upper-level problem using a nonlinear programming solver and solving the lower-level problem using an iterative agent-based assignment-simulation approach. To illustrate the effectiveness of the modeling framework, this study uses traveler demand from Chicago along with the region’s existing multimodal transit network. The computational results indicate significant traveler benefits, in terms of improved average traveler wait times, associated with optimizing the joint design of multimodal transit networks and SAMS fleets compared with the initial transit network design.
Suggested Citation
Helen K. R. F. Pinto, Michael F. Hyland, Hani S. Mahmassani and I. Ömer Verbas (2020) “Joint design of multimodal transit networks and shared autonomous mobility fleets”, Transportation Research Part C: Emerging Technologies, 113, pp. 2–20. Available at: 10.1016/j.trc.2019.06.010.Phd Dissertation
Probabilistic learning for analysis of sensor-based human activity data
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As sensors that measure daily human activity become increasingly affordable and ubiquitous, there is a corresponding need for algorithms that unearth useful information from the resulting sensor observations. Many of these sensors record a time series of counts reflecting two behaviors: (1) the underlying hourly, daily, and weekly rhythms of natural human activity, and (2) bursty periods of unusual behavior. This dissertation explores a probabilistic framework for human-generated count data that (a) models the underlying recurrent patterns and (b) simultaneously separates and characterizes unusual activity via a Poisson-Markov model. The problems of event detection and characterization using real world, noisy sensor data with significant portions of data missing and corrupted measurements due to sensor failure are investigated. The framework is extended in order to perform higher level inferences, such as linking event models in a multi-sensor building occupancy model, and incorporating the occupancy measurement from loop detectors (in addition to the count measurement) to apply the model to problems in transportation research.
Suggested Citation
Jonathan Hutchins (2010) Probabilistic learning for analysis of sensor-based human activity data. Ph.D.. University of California, Irvine. Available at: https://uci.primo.exlibrisgroup.com/permalink/01CDL_IRV_INST/17uq3m8/alma991007581279704701 (Accessed: October 13, 2023).working paper
Projecting Use of Electric Vehicles from Household Vehicle Trials: Trial and Error?
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In 1995-96, the authors participated in an eight-month long trial of prototype EVs, with the proviso that we could use some of the results for academic research. We were particularly interested in comparing data collected from trials with matched data collected from a panel survey. Our objective was to better understand vehicle trials as a source of information for transportation planning and market research, beyond the usual consumer preference information gathered for vehicle design purposes. The methodological issues were of particular concern, for as we discuss in the next section, trials provide useful data at one level, but they can also introduce new sources of bias and uncertainty to data collection and interpretation. We also investigated how perceptions towards EVs would change with the “hands-on” experience of a trial. In this paper we report findings from this trial, with a particular emphasis upon the methodological issues. We intentionally do not discuss purchase intentions, and focus, instead, upon a broader set of results. An objective is to provide transportation planners with useful data about characteristics like vehicle miles travelled, intra-household vehicle switching, and long trip taking when there are multiple data sources from the same respondents, including travel diaries and pre- and post trial panel survey data. This provides insight into how households might choose to use future electric vehicles, and it also addresses the issue of whether trials are an effective and efficient data collection method. The research is expected to provide useful information for those who wish to organize and interpret data from future consumer vehicle trials and it also provides more limited evidence about how households would use future electric vehicles that had a limited range.
Suggested Citation
Thomas F. Golob and Jane Gould (1998) Projecting Use of Electric Vehicles from Household Vehicle Trials: Trial and Error?. Working Paper UCI-ITS-WP-98-2. Institute of Transportation Studies, Irvine. Available at: https://escholarship.org/uc/item/3d82n6k5.conference paper