working paper

Trucking Industry Demand for Information Technology: A Multivariate Discrete Choice Model

Abstract

The objective of this research is to understand the demand for information technology among trucking companies. Of interests in the use of information technologies in both private and for-hire carrier fleet operations. A multivariate discrete technology demand model is developed using data from a large-scale survey of the trucking industry in California. In addition to offering technology providers insight into the market for current and future information technologies the model can inform decisions made by policy analysts about public sector technology implementation aimed at congestion mitigation. The impact of congestion on trucking companies’ profitability and ability to provide timely and reliable service to customers is significant. Successful public sector technology implementation aimed at commercial vehicle operators will be complementary to investments made by companies themselves.

Phd Dissertation

Integration of Locational Decisions with the Household Activity Pattern Problem and Its Applications in Transportation Sustainability

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).

working paper

Parking fees and congestion

Publication Date

January 1, 2001

Author(s)

Abstract

Payment deterioration models are an important input for the efficient management of pavement systems, the allocation of cost responsibilities to various vehicle classes for their use of the highway system, and the design of pavement structures. This paper is concerned with the development of an empirical rutting progression model using an experimental data set from WesTrack. The data used in this paper consist of an unbalanced panel data set with 860 observations. The salient features of the model specification are: 1) three properties of the mix are sufficient to model the performance of the asphalt concrete pavement accurately, 2) the model captures the effects of high air temperatures at WesTrack, and 3) the model predicts rut depths by adding predicted values of the increment of rut depth for each time period, which is particularly advantageous in a pavement management context. The three mix properties are a gradation index, which is obtained from the aggregate gradation, the voids filled with asphalt obtained for the construction mix in the Superpave gyratory compactor, and the initial in-place air voids. The specified model is non-linear in the variables and the parameters, and is estimated using a random effects specification to account for unobserved heterogeneity. The estimation results and prediction tests show that the model replicates the observed pavement behavior at WesTrack well.

published journal article

A multi-criteria decision support methodology for implementing truck operation strategies

Transportation

Publication Date

July 1, 2012
Suggested Citation
Choong Heon Yang and Amelia C. Regan (2012) “A multi-criteria decision support methodology for implementing truck operation strategies”, Transportation, 40(3), pp. 713–728. Available at: 10.1007/s11116-012-9432-7.

working paper

Traffic Congestion and Trucking Managers' Use of Automated Routing and Scheduling

Abstract

Using data from a 2001 survey of managers of 700 trucking companies operating in California, we tested competing hypotheses about the relationship between managers’ perceptions of the impact of traffic congestion on their operations and their companies’ adoption of routing and scheduling software. Demand for automated routing and scheduling was found to be influenced directly by the need to re-route drivers, and indirectly by the need, generated by customers’ schedules, to operate during congested periods. We were also able to identify which types of trucking companies are most affected by congestion and which types are more likely to adopt such software.

conference paper

Changes in activity-travel behavior of workers before and after the 2009 recession

Proceedings of the 98th annual meeting of the transportation research board

Publication Date

January 1, 2019

Abstract

A daily tour choice model is developed for workers by hypothesizing structural relationships between activity-travel participation (time use) and choice of work and non-work tours. The model reflects tour behavior at three intervals: 3 years before the 2009 recession, during the recession, and three years after. Multiple-group structural equation models (SEM) enable an investigation of interrelationships between work (both at home and out-of-home) and non-work (out-of-home) activity time by time-of-day, by associated travel times, and the choice of tour type. The effects of socio-demographic variables on each of the activity-travel time and tour choice variables are also captured. The model also allows comparison among these relationships across pre-, during, and post-recession years. Using data from the American Time Use Survey (ATUS), the study shows that activity-travel relationships and their influence on tour choice differed significantly in the recession year (2009) compared to pre- and post-recession years. For example, during the recession people working at home preferred making out-of-home non-work activities before starting work. In the same year, the likelihood of people with multiple jobs choosing work-only tours increased. The research findings advance the understanding of tour choice as well as activity-travel behavioral change of workers during an economic downturn.

Suggested Citation
Rezwana Rafiq and Michael G. McNally (2019) “Changes in activity-travel behavior of workers before and after the 2009 recession”, in Proceedings of the 98th annual meeting of the transportation research board, p. 7p.

conference paper

Accessibility of health care

Proceedings, 8th Annual Urban Symposium, Association for Computing Machinery

Publication Date

January 1, 1973

Author(s)

R. E. Paaswell, Will Recker
Suggested Citation
R. E. Paaswell and W. W. Recker (1973) “Accessibility of health care”, in Proceedings, 8th Annual Urban Symposium, Association for Computing Machinery, pp. 49–58.

working paper

Multiple Imputation Methodology for Missing Data, Non-Random Response and Panel Attrition

Publication Date

March 1, 1997

Author(s)

Working Paper

UCI-ITS-WP-97-4, UCTC 594

Abstract

Modern travel-behavior surveys have become quite complex; they frequently include multiple telephone contacts, travel diaries, and customized stated preference experiments. The complexity and length of these surveys lead to pervasive problems with missing data and non-random response biases. Panel surveys, which are becoming common in transportation research, also suffer from non-random attrition biases. This paper shows how Rubin’s (1987a) multiple imputation methodology provides a unified approach to alleviating these problems. Before discussing solutions to problems caused by missing data and selection, it is important to recognize that their presence causes fundamental problems with identifying models and even “simple” population estimates. Section 2 reviews this work and stresses the need to make generally untestable assumptions in order to carry out any inference with missing data.

Suggested Citation
David Brownstone (1997) Multiple Imputation Methodology for Missing Data, Non-Random Response and Panel Attrition. Working Paper UCI-ITS-WP-97-4, UCTC 594. Institute of Transportation Studies, Irvine. Available at: https://escholarship.org/uc/item/03f6g5zx.

Phd Dissertation

Time-bounded cooperative recovery from hardware and software faults in real-time distributed computer systems

Abstract

TBD

Suggested Citation
Luiz Fernando Huet De Bacellar (1996) Time-bounded cooperative recovery from hardware and software faults in real-time distributed computer systems. PhD Dissertation. UC Irvine. Available at: https://uci.primo.exlibrisgroup.com/permalink/01CDL_IRV_INST/17uq3m8/alma991018567979704701.