Huan-Sheng Hwang

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—A full-wave moment-method technique developed for the analysis of quasi-optical (QO) systems is used to model finite grid structures in a lens system. This technique incorporates an electric-field dyadic Green's function for a grid centered between two lenses. This is derived by separately considering paraxial and nonparaxial fields. Results for the(More)
NUTESON, TODD WILLIAM. Electromagnetic Modeling of Quasi-Optical Power Combiners. (Under the direction of Michael B. Steer.) A full-wave electromagnetic simulator is developed for the analysis of finite antenna elements and grid arrays in quasi-optical systems. This electromagnetic simulator employs an efficient Galerkin moment method technique with(More)
—A dual-band R-shaped planar inverted-F antenna is proposed for vehicular application. Utilization of this unique geometry dual-frequency operation is achieved with a single feed. The proposed antenna operates in the 225-and 450-MHz bands. Input impedance and return loss data as function of various antenna parameters are presented, which show that(More)
Acknowledgment I wish to express my sincere appreciation to those who provided support, encouragement and assistance throughout the project and preparation of this thesis. First, I would like to express my gratitude to my advisor Dr. Michael B. Steer for his support and guidance during my graduate studies. I would also like to thank my past and present(More)
The solution combustion process is used to synthesize Fe1.9925P0.0075O3 nano-powders. The sintered Fe1.9925P0.0075O3 bodies are alpha-Fe2O3-based single phase with the rhombohedral structure. The electrical conductivity increases with an increase in sintering temperature because of an increase in grain size and density. The absolute value of the Seebeck(More)
We successfully synthesized nano-sized Ce(0.8)Gd(0.2)O(2-delta) powders by combustion method, using gelatin as fuel. The calcined powders showed high-quality characteristics, i.e., nano-scale size (14-35 nm) and narrow size distribution. The structural, morphological, and electrical characteristics of the sintered Ce(0.8)Gd(0.2)O(2-delta) were studied(More)
Nano-sized Ca3Co(4-x)Mn(x)O9 (0 < or = x < or = 0.6) thermoelectric powders were synthesized by solution combustion method, using aspartic acid as fuel. The microstructure and high-temperature (500-800 degrees C) thermoelectric properties of the Ca3Co(4-x)Mn(x)O9 were investigated. The addition of Mn for Co in Ca3Co(4-x)Mn(x)O9 resulted in a decrease of the(More)
Ce(0.8)Sm(0.2)O(2-delta) and Ce(1-x)Gd(x)O(2-delta) (0.1 < or = x < or = 0.3) nano-sized powders were successfully synthesized by the solution combustion synthesis process. The calcined nanopowders showed a ceria-based single phase with a cubic fluorite structure. In this study, we discussed the structural and electrical characteristics of the sintered(More)
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