Engineering Commons^™

Electric Vehicles In China: Emissions, Health Impacts, And Equity, Shuguang Ji

Doctoral Dissertations

E-bikes in China are the single largest adoption of alternative fuel vehicles in history, with more than 100 million e-bikes purchased in the past decade and vehicle ownership about 2× [time] larger for e-bikes as for conventional cars; e-cars sales, too, are rapidly growing. Electric vehicles (EVs) in China are being considered as a strategy to improve air quality, energy efficiency, and reduce health impacts due to transport emissions. Because EVs have different pollution sources, namely electric generating units (EGUs), quantitative analysis for health impacts requires understanding the exposure efficiency of related pollution sources. In this dissertation, EVs will be …

Application Of Highway Capacity Manual 2010 Level-Of-Service Methodologies For Planning Deficiency Analysis, James Oliver Ensley

Masters Theses

Influence on investment in the infrastructure is critical for decision-making by State planning departments. Judgments which are made for funding purposes and are based on limited data analysis by states can results in economic disasters for the state and nation. The Tennessee Department of Transportation (TDOT) uses the Evaluation of Roadway Efficiency (EVE) database to prioritize the importance of roadway projects in the state. In addition, EVE is also used as a method to provide deficiency analysis results for roadways in the state. This study will add support to the methodology of the current decision-making process in regards to Tennessee …

Driving Simulator Transportation Safety: Proper Warm-Up Testing Procedures, Distracted Rural Teens, And Gap Acceptance Intersection Sight Distance Design, Ryan Andrew Overton

Doctoral Dissertations

Driving Simulators have become invaluable tools for researchers through technological advancements of the twenty-first century. With increasing availability and affordability of these systems, this dissertation focuses on three research projects utilizing the University of Tennessee’s high fidelity driving simulator.

Chapter I discusses how previous research efforts reveal inconsistencies in acclimating test participants to driving simulators. Through proper warm-up time periods, researchers can be confident that the test subjects are comfortable with the handling of the simulator vehicle. This will create reliable test results for the researcher’s analysis. The warm-up acclimation study found that approximately 65% - 85% of the sample …

Studies Of Driver Behaviors And Traffic Flow Characteristics At Roadway Intersections, Qiang Yang

Doctoral Dissertations

The performances of intersections and driveway access points are crucial to a road network in terms of efficiency and safety. Driver behavior and traffic flow characteristics at these locations are relatively complex. To better understand these issues and potentially provide guidance to engineers in their designs, a series of studies were performed on the driver behavior and traffic characteristics at intersections and driveway access points based on field experiments or observations.

First, a countdown timers study was performed in China about their influences on driver behavior. It was found that the presence of countdown timers may encourage yellow running behavior …

Effects Of Highway Geometric Features And Pavement Quality On Traffic Safety, Ximiao Jiang

Doctoral Dissertations

Curbs are commonly used on roadways to serve for drainage managing, access controlling and other positive functions. However, curbs may also bring about unfavorable effects on drivers’ behavior and vehicles’ stability when hitting curbs, especially for high-speed roadways. In addition, numerous pavements have been experiencing wear off rapidly in recent decades, which significantly affected driving quality. However, previous study of pavement management factors as related to the happening and outcome of traffic-related crashes has been rare. The objective of this dissertation is to evaluate the influences of outside shoulder curbs, pavement management factors, and other tradition traffic engineering factors on …

Efficacy Of A Ternary Blend In Improving Bridge Deck Concrete Durability In Tennessee, Robert Clark Nidiffer

Masters Theses

A study related to the durability of bridge deck concrete in the state of Tennessee has been ongoing at the University of Tennessee (UT) for the past decade. The most recent phase of this research was begun in the fall of 2009 with a focus on developing assessment criteria and methodology to assess the durability of bridge deck concrete in the state of Tennessee. The methodology that was used to assess the durability of Tennessee bridge deck concrete was to determine the concrete’s resistance to chloride ion penetration by way of two test methods, the Surface Resistivity (SR) test and …

Hydrologic Reconstructions Using Dendroclimatology, Climate Signals, And Pacific Ocean Sea Surface Temperature Variability, Sallyrose Anderson

Doctoral Dissertations

The Colorado River provides water to over 25 million people. Given the importance of this water supply, it is critical to understand the hydrologic variables in the Colorado River Basin. In this dissertation, I reconstructed hydrologic conditions (soil moisture, snowpack) in the Upper Colorado River Basin (UCRB) and examined different factors that influence water supply in the region (climate oscillations, oceanic-atmospheric variability).

Firstly, I reconstructed soil moisture in the UCRB. Principal components analysis (PCA) and k-Nearest Neighbor (k-NN) techniques were used to regionalize the gridded data. Correlated tree-ring chronologies (TRCs) were used as predictor variables in stepwise linear regression (SLR) …

Hydrology, Soil Erosion And Climate Interactions On Low Compaction Steep-Sloped Reclaimed Sites In The Southern Appalachian Coal Fields, Tennessee, Siavash Hoomehr

Doctoral Dissertations

The use of loose spoil on steep slopes for surface coal mining reclamation sites has been promoted by the US Department of Interior, Office of Surface Mining for the establishment of native forest. Although low-compaction spoils improve tree survival and growth, the erodibility and hydrology of steep slopes may change due to this practice. The purpose of this study was to quantify the erodibility (K factor), and the Curve Number (CN) value for low compaction, steep-sloped (> 20%) reclaimed mine lands in the Appalachian region, USA. This study also investigated the performance of the SEDCAD model in estimating erosion and …

A Benefit Cost Model For Traffic Incident Management, Sam Dallas Moss

Masters Theses

Every day, non-recurring incidents cause delay on major roadways and cost the public valuable time and, hence, money. Some public agencies have systems that help them to identify and mitigate the problems associated with incidents such as delay. These systems are referred to as Traffic Incident Management systems. Many different agencies have searched for a way to quantify the benefits that these programs provide. This thesis details how a model was developed to help these agencies easily quantify the benefits that can be derived from saving delay through efficient incident management. This model uses real traffic data collected by roadway …