Effect of trip attributes on ridehailing driver trip request acceptance

A generalized additive mixed model was estimated to investigate the factors that impact ridehailing driver trip request acceptance choices, relying on 200 responses from a stated preference survey in Seattle, US. Several policy recommendations were proposed to promote trip request acceptance based on ridehailing drivers willingness to accept compensation for undesired trip features. The findings could be useful for transportation agencies to improve ridehailing service efficiency, better fulfill urban mobility needs, and reduce environmental burden.Comment: Paper in print at Journal of Sustainable Transportatio

Travel Behavior Modeling and Emerging Mobility Technologies - Annual Report from the University of Washington To Argonne National Laboratory

This report presents work completed at the University of Washington in 2020-21 under contracts with Argonne National Laboratory. Specifically, it includes work completed in the fourth year of the UW’s efforts on the US-China Clean Energy Research Center - Clean Vehicles Consortium (CERC-CVC), and work under the Systems and Modeling for Accelerated Research in Transportation (SMART) consortium. The work completed includes survey design, data collection, and modeling. Specifically, we report on: 1. Modeling and analysis of autonomous vehicle mode choices and car ownership decisions that leverage data collected in prior years with CERC-CVC support. 2. Collection of data on travelers’ preferences for solo and pooled ridehailing services, taking advantage of a survey that was designed with prior CERC-CVC support but delayed by the onset of the COVID-19 pandemic. We also report on modeling efforts employing these data. 3. Design and administration of a stated choice survey of ridehailing drivers, aimed at collecting data to support modeling of drivers’ working time, location, and trip request acceptance decisions. We also include a summary of some practical lessons learned about surveying this hard-to-reach group. 4. Analysis of changes in transit usage before and during the COVID-19 pandemic, exploring differences between those who plan to return to transit and those who do not. 5. The design of a survey intended to link personality traits with preferences for autonomous vehicles and for sharing rides in ridehailing services

Assessing Agricultural Drought Vulnerability by a VSD Model: A Case Study in Yunnan Province, China

Drought vulnerability of agriculture is significant to economic development and sustainable food production. In this paper, we proposed a framework to evaluate the regional agricultural-eco environment in the face of drought caused by climate change. Based on a vulnerability scoping diagram (VSD) model, we built up a comprehensive system to evaluate the agricultural drought vulnerability of Yunnan Province in China. The model highlights the human-land relationship by considering both natural conditions and human activities. Twelve indicators were generated to construct three components of the model: exposure, sensitivity, and adaptive capacity. During the construction of the VSD model, the entropy and the analytic hierarchy process (AHP) comprehensive analysis method were adopted to generate the weights and to compute the composite index for each section. Furthermore, the factor analysis method was used to determine the dominant factors of different cities and the main indicators driving the system. The results indicated a spatial pattern that the vulnerability value was high on the eastern and western sides, but low in the middle of Yunnan Province. Most of the vulnerable regions were concentrated in remote areas. Indicators such as population density, irrigation level, annual average precipitation, cultivation land ratio, and difficulty of water supply were the main driving factors. This means that there is a deep connection between agricultural drought vulnerability and urbanization. The evaluation system developed during this research will provide guidance for drought mitigation in regions of complex terrain

Gas-Dependent Active Sites on Cu/ZnO Clusters for CH₃OH Synthesis

This study describes an instantaneously gas-induced dynamic transition of an industrial Cu/ZnO/Al2O3 catalyst. Cu/ZnO clusters become “alive” and lead to a promotion in reaction rate by almost one magnitude, in response to the variation of the reactant components. The promotional changes are functions of either CO2-to-CO or H2O-to-H2 ratio which determines the oxygen chemical potential thus drives Cu/ZnO clusters to undergo reconstruction and allows the maximum formation of Cu–Zn2+ sites for CH3OH synthesis

Gas-Dependent Active Sites on Cu/ZnO Clusters for CH₃OH Synthesis

This study describes an instantaneously gas-induced dynamic transition of an industrial Cu/ZnO/Al2O3 catalyst. Cu/ZnO clusters become “alive” and lead to a promotion in reaction rate by almost one magnitude, in response to the variation of the reactant components. The promotional changes are functions of either CO2-to-CO or H2O-to-H2 ratio which determines the oxygen chemical potential thus drives Cu/ZnO clusters to undergo reconstruction and allows the maximum formation of Cu–Zn2+ sites for CH3OH synthesis