Engineering Commons^™

Evapotranspiration Estimation: A Study Of Methods In The Western United States, Clayton S. Lewis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Theoretical water use of well-watered vegetation in the western United States was investigated by comparing a gridded dataset developed from satellite and ground instruments to weather stations representative of irrigated agricultural conditions. Since wetter environments are cooler and therefore subject to lower levels of evaporation than the same scenario with warmer temperatures, models derived from dryland and often populated areas overestimate potential plant needs in semi-arid or arid conditions. Evaluation of the model revealed an acceptable fit for air temperatures and solar radiation but with less confidence in humidity and wind speeds. Ultimately, the last two parameters were minor components …

A Comprehensive Safety Analysis Of Diverging Diamond Interchanges, Holly Lloyd

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With the implementation of new roadway configurations, there is a great need to study the influence of the roadway design on the crash rate. Utah is one of the leading states in the implementation of the Diverging Diamond Interchange.

In order to determine the effects of the new roadway configuration on the safety of the intersection, this study employs an Empirical Bayes before-after study of the crash rates at selected Diverging Diamond Interchanges in Utah. The results of the Empirical Bayes method were also used to calculate crash modification factors. The total number of crashes at each site were analyzed. …

Traffic Sign Management: Data Integration And Analysis Methods For Mobile Lidar And Digital Photolog Big Data, Majid Khalilikhah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Traffic signs often convey critical information to drivers. However, traffic signs are only effective when clearly visible and legible. This study aims to determine the effects of various damage and deterioration forms on sign retroreflectivity, identify the most important factors affecting traffic sign visual condition, predict traffic sign vandalism that obstructs critical messages to drivers, and identify important environmental factors contributing to the temporary obstruction of the sign messages. To do so, two data sets are used. A sample data of over 1,700 signs was manually collected in the field, and the background retroreflectivity of each sign was measured using …