Engineering Commons^™

Ultrasonic Signal Detection And Recognition Using Dynamic Wavelet Fingerprints, Jidong Hou

Dissertations, Theses, and Masters Projects

A novel ultrasonic signal detection and characterization technique is presented in this dissertation. The basic tool is a simplified time-frequency (scale) projection which is called a dynamic wavelet fingerprint. Take advantage of the matched filter and adaptive time-frequency analysis properties of the wavelet transform, the dynamic wavelet fingerprint is a coupled approach of detection and recognition. Different from traditional value-based approaches, the dynamic wavelet fingerprint based technique is pattern or knowledge based. It is intuitive and self-explanatory, which enables the direct observation of the variation of non-stationary ultrasonic signals, even in complex environments. Due to this transparent property, efficient detection …

Synthysis Of Polymer/Nano-Droplet Composites From Reverse Microemulsion Polymerization, Liehui Ge

Master's Theses and Doctoral Dissertations

L₁ and L₂ domains of the water/AOT/MMA ternary system were investigated at 22±1°C. Free radical polymerizations were conducted in L₂ domain. Only opaque polymer rods were obtained. Acrylamide, a water soluble monomer, plays a role of co-surfactant which greatly expands the L₂ domain. However, polymerizations only yielded opaque material. SEM showed images of phase separation.

MDOS (2-Methacryloyloxy)ethyl trimethylammonium bis(2-ethylhexyl) sulfosuccinate, was synthesized by ion exchange method. L₁ and L₂ domains of the water/MDOS/MMA ternary system were also investigated at 22±1°C. Free radical polymerizations were conducted in L₂ domain. Transparent polymer was produced. The …