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An ultra-wideband (UWB) spatial filter is proposed to mitigate multipath effects in a one-way, one-dimensional time-of-arrival (TOA) localization system for use inside a tunnel. The spatial filter is a weighted array of judiciously placed antennas and it exploits the fact that electromagnetic waves propagate as modes in a tunnel by selectively extracting these mode(s). The design of several spatial filters is presented alongside vigorous analyses to characterize the localization performance afforded by them in a noisy environment. The filters are evaluated using data from an analytical equation waveguide model, a ray tracer model and measurements. These spatial filters deliver accurate localization estimates across distance and well-designed filters can operate at higher SNRs and further distances than single sensors. Insights into successful spatial filter design are provided and this spatial filtering technique has created a new branch of multipath-aware localization systems.

This thesis describes the development and assessment of an undergraduate wind tunnel test engineering course utilizing the 7ft by 10ft Oran W. Nicks Low Speed Wind Tunnel (LSWT). Only 5 other universities in the United States have a wind tunnel of similar size and none have an undergraduate wind tunnel test engineering course built around it. Many universities use smaller wind tunnels for laboratory instruction, but these experiments are meant to only demonstrate basic concepts. Students go beyond conceptual learning in this wind tunnel test engineering course and conduct real-world experiments in the LSWT. This course puts knowledge into practice and further prepares students whether continuing on to graduate school or industry. Course content mainly originates from the chapters in Low Speed Wind Tunnel Testing by Barlow, Rae, and Pope. This is the most comprehensive book that addresses the specific requirements of large scale, low speed wind tunnel testing. It is not a textbook for novices. The three experiments used in the course are modeled on actual experiments that were performed at the LSWT. They are exactly what a commercial entity would want performed although the time scale is drastically reduced because of class requirements. Students complete the course with a working knowledge of the requirements of large scale, low speed wind tunnel tests because they have successfully performed real-world tests and have performed data reduction that is needed for high-quality industrial tests.

Achieving high quality, consistency, and testing efficiency in wind tunnel tests using internal balances is accomplished through the use of new testing methods, analysis of data output, and standardized documentation of test procedures at the Texas A&M Low Speed Wind Tunnel. The wind tunnel is capable of performing internal balance testing on models that experience less than 500 pounds of normal force. Testing has shown less than a 3% mean flow variation with the sting mount installed and a turbulence intensity of less than 0.25%. Documentation of procedures and check- lists for installation of internal balance testing equipment and test execution provide higher efficiency and consistency during a test. A step-by-step examination of the data analysis routines and associated uncertainty equations show uncertainty in the force and moment coefficients for the Mark XIII internal balance to be approximately ± 0.05 and ± 0.02, respectively. Quantifying the uncertainty of the primary output parameters and showing repeatability of the data within the defined uncertainty limits achieved higher quality results.

The Bolu Tunnels lie along Trans European Motorway (TEM) which is connecting Eastern Europe with the Middle East. The tunnels are approximately 3.0 km long, 40 m apart and have excavated cross sections more than 200 m2. In construction, New Austrian Tunneling Method (NATM) was used in soft ground. Due to the challenging ground conditions, many problems have been encountered during tunnelling. To solve these problems special construction techniques were adapted. To simulate and demonstrate the effectiveness of these construction techniques, 2D and 3D Finite Element Methods are utilized in this study. Through comparison between 2D and 3D modelling of advance of Bolu Tunnels, respective merits of these two approaches are investigated and the conditions under which shortcomings of the 2D approach become serious are identified.

Thesis (Ph. D.)--University of Washington, 1991. / Vita. Includes bibliographical references (leaves [154]-167).

Thèses (Ph.D.)--Université de Sherbrooke (Canada), 2002. / Titre de l'écran-titre (visionné le 20 juin 2006). Publié aussi en version papier.

Thèses (M.Sc.A.)--Université de Sherbrooke (Canada), 1998. / Titre de l'écran-titre (visionné le 20 juin 2006). Publié aussi en version papier.

Thèses (M.Sc.)--Université de Sherbrooke (Canada), 2000. / Titre de l'écran-titre (visionné le 30 août 2006). Publié aussi en version papier.