Phd Dissertation

Sacred placemaking and urban policy the case of Tepoztlán, Mexico

Publication Date

June 30, 2020

Author(s)

Abstract

Sacred places – ranging from religious to secular structures, human created or natural areas, or places with ritual, symbolic, or cultural significance – are rarely addressed by urban planners but are sources of great meaning for many communities. One reason for this neglect is the inherent difficulty in measuring the value and meaning of place for different individuals or groups. This research focused on this challenge by using ethnographic field research methods to gain an in-depth understanding of how people view and interact with sacred places in their community. The case study site of Tepoztlán is an urbanizing pueblo in central Mexico where sacred places play a significant role in daily life, rituals, and festivals and urban forms facilitate these interactions. I asked how sacred meaning was ascribed to places in Tepoztlán, how the built environment impacted behavior around these spaces, how communities preserved sacred places, and the impacts of urbanization on preservation efforts. Findings derived from 53 interviews and three months of field observations revealed five themes characteristic of sacred placemaking in Tepoztlán, including intricate patterns of neighborhood exchange, intergenerational beliefs in sacred mountains, collectivism, pedestrian oriented design, and community involvement in construction of the built environment. Indigenous placemaking is then contrasted with two top-down urban development policies that changed the character of the town and threatened sacred places and placemaking. A tourism program called Pueblos Mágicos [Magical Towns] and expansion of the Pera-Cuautla freeway have degraded and commodified sacred sites and perpetuated unequal distribution of development benefits. The research discusses how employing different views of people-environment interactions beyond dominant Western views can help planners to better understand and plan for preservation of meaningful spaces and in turn preserve and enhance community identity, culture, and self-sufficiency. 

working paper

Dynamic Path-Based Equilibrium Assignment With Microscopic Traffic Simulation

Publication Date

April 1, 2005

Author(s)

Henry Liu, Will Recker

Abstract

This report summarizes research work conducted under TO4158 at the California ATMS Testbed of the Institute of Transportation Studies at the University of California, Irvine. Under this task order, the California ATMS testbed hosted two full-time PATH research postdocs (Henry Liu and Lianyu Chu) whose general responsibilities are focused on applications of ATMS in the Testbed environment. They are generally responsible for ensuring that the functional capabilities of the Testbed are designed, developed and maintained in a manner that complements and enhances the ATMS research objectives of the PATH program. Under the direction of PATH faculty researchers at UCI and the Testbed management team, they are generally responsible for software enhancements to the Laboratory “bench-top” system for modeling and evaluating ATMS, particularly with the microscopic simulation model Paramics. They also provided Caltrans the on-call support and technical guidance on various Caltrans micro-simulation projects related to the Paramics plugin modules developed at UCI. In addition to the general responsibilities outlined above, the PATH Researchers have specific research projects. The specific research project conducted under this task order is to develop a path-based equilibrium assignment model with micro-simulator Paramics. Since off-the-shlef Paramics can only do the link-based assignment, no path information during the traffic assignment process is stored nor provided. This will bring difficulties in the ATMS evaluation particularly related to the route diversion because partial or full path information is needed to conduct this type of evaluation with Paramics. To overcome this difficulty, a path-based assignment model is developed using Paramics Application Programming Interfaces (API) functions. The model comprises the advantages of the analytical traffic assignment model and the good properties of the simulation tools, which can represented the real world more properly. Some key techniques, route choice plug-in, turn penalty consideration and methods of successive average, and etc., were applied in the model. The Paramics V4 was selected as the demonstration simulation tool. A real grid network in Tucson, Arizona, was designed to test the performance of the model, and the results showed that the model converged to the user equilibrium as expected.

working paper

Death on the Crosswalk: A Study of Pedestrian-Automobile Collisions in Los Angeles

Publication Date

April 1, 2005

Author(s)

Anastasia Loukaitou-Sideris

Abstract

This research explores the spatial distribution of pedestrian-automobile collisions in Los Angeles and analyzes the social and physical factors that affect the risk of getting involved in such accidents. More specifically, this study investigates the influence of socio-demographic, land use, density, and traffic characteristics on pedestrian accident rates.

We first provide an exploratory spatial and statistical analysis of pedestrian collision data in the city of Los Angeles to identify preliminary relationships between accident frequency and socio-demographic and land use characteristics at the census tract and block group levels. This aggregate level analysis also helps us identify major concentrations of pedestrian collision data which are used at a second stage of the research for more qualitative and detailed analysis of specific case studies of intersections with high frequency of pedestrian-automobile accidents. The study uses pedestrian accident data provided by the Los Angeles Department of Transportation, traffic volume data provided by Caltrans, socio-demographic data from the U.S. Census 2000, land use data from the Southern California Association of Governments (SCAG), and pedestrian volume and built environment data from fieldwork research.

working paper

The Economic Effects of Highway Congestion

Publication Date

October 1, 1995

Author(s)

Abstract

This paper examines the link between highway congestion, labor productivity, and output in a sample of California counties for the years 1977 through 1987. A county production function is modified to include both the value of each county’s highway capital stock and a measure of the congestion on each county’s highway network. This allows a comparison of two distinct policies — expanding the highway stock versus reducing congestion on the existing stock. The productive effects of congestion reduction are significantly positive in five of six regression specifications. The effects of expanding the highway stock are more suspect, and are insignificant in what are arguably the preferred specifications. Overall, the results provide evidence that efficiently using the existing highway network is more likely to yield economic benefits than expanding the highway stock.

Preprint Journal Article

Provably Safe and Human-Like Car-Following Behaviors: Part 1. Analysis of Phases and Dynamics in Standard Models

Abstract

Trajectory planning is essential for ensuring safe driving in the face of uncertainties related to communication, sensing, and dynamic factors such as weather, road conditions, policies, and other road users. Existing car-following models often lack rigorous safety proofs and the ability to replicate human-like driving behaviors consistently. This article applies multi-phase dynamical systems analysis to well-known car-following models to highlight the characteristics and limitations of existing approaches. It begins by formulating fundamental principles for safe and human-like car-following behaviors, which include zeroth-order principles for comfort and minimum jam spacings, first-order principles for speeds and time gaps, and second-order principles for comfort acceleration/deceleration bounds as well as braking profiles. From a set of these zeroth- and first-order principles, it derives Newell’s simplified car-following model. Subsequently, the study analyzes phases within the speed-spacing plane for the stationary lead-vehicle problem in Newell’s model and its extensions, which incorporate both bounded acceleration and deceleration. It then analyzes the performance of the Intelligent Driver Model and the Gipps model. Through this analysis, the study highlights the limitations of these models with respect to some of the aforementioned principles. Numerical simulations and empirical observations validate the theoretical insights. Finally, it discuss future research directions to further integrate safety, human-like behaviors, and vehicular automation in car-following models, which are addressed in Part 2 of this study, where it develops a novel multi-phase projection-based car-following model that addresses the limitations identified there.

Preprint Journal Article

Beyond Infrastructure: Patterns of Environmental Justice and Multi-Level Governance in Greater Los Angeles Transportation and Hazard Planning

Abstract

This study evaluates how environmental justice principles are integrated into transportation and hazard plans across multiple levels of jurisdictions in Greater Los Angeles, revealing how the multi-level governance framework shapes planning practices for environmental justice integration across levels and over time. A content analysis was conducted on 16 transportation, hazard preparedness, climate action, and racial equity plans to develop a scoring methodology. Through comparison the study identified patterns and factors contributing to effective environmental justice integration in transportation and hazard planning. Findings show that although infrastructure (transportation and hazard) plans achieve higher environmental justice integration on average than other plans after 2019, some subdimensions – like recognition justice – remain less integrated. Curiously, the positive trend between environmental justice and multi-level governance observed for climate action and racial equity plans is not observed for infrastructure plans, suggesting greater nuance among the strategies that lead to its successful integration in infrastructure planning.

blog

How a Charging-As-A-Service Model Could Support and Expand Electric Vehicle Charging Stations

Abstract

California aims to dramatically increase its electric vehicle (EV) charging infrastructure, but faces significant challenges. A new business model called charging-as-a-service (CaaS) could help overcome these obstacles and support the state’s ambitious climate goals.

policy brief

Charging-as-a-Service is an Innovative Business Model that Could Help with California’s Vehicle Electrification Goals

Abstract

Access to electric vehicle (EV) charging infrastructure is critical to advancing California’s EV adoption goals. The California Energy Commission has projected the state needs “nearly 1.2 million” chargers by 2030 “to meet the fueling demands of 7.5 million passenger plug-in electric vehicles.” Currently, California has about 152,000 publicly available EV chargers.

Innovative asset ownership models, like charging-as-a-service (CaaS), could help overcome some of the barriers to deploying and maintaining charging infrastructure. For example, CaaS providers could procure, install, maintain, and replace charging equipment for subscription customers. To better understand how CaaS solutions could expand EV use and charging access, this researchers conducted semi-structured interviews with 13 CaaS companies, electric utilities, and customers to identify the perceptions, challenges, and opportunities of the CaaS business model in addressing charging station needs in California.

research report

Assessing the Charging-as-a-Service (CaaS) Model for EV Charging Deployment in California

Abstract

Charging-as-a-Service (CaaS) is an innovative electric vehicle (EV) charging station model that allows customers access to EV chargers through a contract with a provider responsible for design, deployment, operations, and maintenance. Little is known about the motivations and experiences of stakeholders involved in CaaS operations, including providers, electric utilities, and customers. A grey literature review identified CaaS services, provider-described benefits, and utility-provided CaaS and charging services. Then, semi-structured interviews were conducted with 13 stakeholders to identify critical themes on interactions between stakeholders and the perceptions, challenges, and opportunities of the CaaS business model in addressing charging station needs in California. CaaS may have structural benefits to customer-owned chargers and could improve charger reliability, provide scalable solutions, and reduce customer fatigue with EV charging deployment. However, CaaS faces the same challenges present in the broader charging industry. The findings in this study can guide policymakers in supporting maintenance-related workforce development and streamlining and crafting EV charging infrastructure-informed subsidy programs. Additionally, stakeholders recommend municipal-led EV infrastructure planning and funding for chargers in disadvantaged communities. These interviews clarify the role of CaaS within the EV charging industry and confirm the need for engaged policymaker support to clear roadblocks, support investment, and educate customers about decision-making, which benefits all EV charging stakeholders.