Digital Commons Network^™

Modeling Route Choice Of Utilitarian Bikeshare Users From Gps Data, Ranjit Khatri

Masters Theses

This research examines the behavior of bikeshare users from Grid Bikeshare Program in Phoenix, Arizona under two behavioral frameworks: facility usage assessment and route choice assessment. The analysis is performed for the two different categories of subscribers: registered and casual subscribers. This is the first study that uses the real-time GPS data from bikeshare users to model their route preferences. The data used for this study were obtained from 9,101 trips made by 1,866 bikeshare. An important aspect of this bikeshare is that it allows non-station origin and destinations. The GPS points collected from the trips made by bikeshare users …

Gis-Based Streambank Video Mapping To Determine Erosion Susceptible Areas, Brett Allen Connell

Masters Theses

According to the U.S. Environmental Protection Agency, excess sediment is a significant cause of water quality impairment for rivers (USEPA, 2009). Therefore, determining the areas of river where streambank erosion is the highest should provide valuable information. Considering the amount of funds being spent on river restoration and storm flow retention, there needs to be a more efficient method to document annual conditions, on a watershed scale. Traditional streambank survey methods are limited in total characterized area, time consuming, environmentally intrusive, and expensive. This project describes the development of a Bank Erosion Susceptibility Index (BESI) to map landscape scale, streambank …

A Gps-Based Mobility Power Model For Military Vehicle Applications, George William Bozdech

Masters Theses

In recent years, military vehicles have been equipped with hybrid, diesel-electric drives to improve fuel efficiency and stealth capabilities. These vehicles require an accurate estimate of the power duty cycles during distinct operating conditions. To meet this demand, a GPS-based mobility power and duty cycle analysis is one approach to predict the power requirements of on-road and off-road vehicles. The dynamic vehicle parameters needed to estimate the forces developed during locomotion are determined from the GPS tracking data, and these forces include the following: the motion resistance, gravitational, linear inertia, rotational inertia, and aerodynamic drag. The motion resistance force generated …

Short Distance Ground Wave Propagation Modeling In Irregular And Forested Environments, Zachary Michael Crane

Masters Theses

A model for the phase of a ground wave propagating over irregular and forested terrain has been developed and tested for a transmission system operating at 3.315 MHz.

In this model, the time delay induced beyond that of the standard velocity of radio waves in air is modeled as a combination of 3 effects: the finite conductivity of the earth, the irregularity of the terrain over which the wave is propagating, and the forestation of the terrain.

The finite conductivity model is based on a small curvature formula developed by Van Der Pol and Bremmer. The terrain irregularity model models …