Digital Commons Network^™

Determining Level Of Cognitive Impairment Via Computing Fractals Using A Computer, Kodhanda Karthik Siriyala

USF Tampa Graduate Theses and Dissertations

Mild Cognitive Impairment is a condition that affects an individual's thinking and decision making capabilities. Specifically, it is one where an individual's capabilities of memorizing, thinking and decision making are less efficient when compared to others. In order to diagnose this condition, a conventional method is to provide the subject with a small challenge they should be completed using pen and paper. This thesis focuses on how this method can be converted to a computer based test. A data visualization tool named Processing has been used to develop a system that runs a game-like test, which is completed by individuals …

Resonance Ultrasonic Vibrations (Ruv) For Crack Detection In Silicon Wafers For Solar Cells, William Dallas

USF Tampa Graduate Theses and Dissertations

The photovoltaic industry provides a pathway to allow renewable energy to meet world wide consumer energy needs. Past and present research and development on silicon based solar cells have helped make them the dominant player in the photovoltaic industry accounting for over 75% in 2005 as accounted by the US Department of Energy. One of the current technological problems is to identify and eliminate sources of mechanical defects such as thermo-elastic stress and cracks leading to the loss of wafer integrity and ultimately breakage of as-grown and processed Si wafers and cells.The RUV method, developed at the University of South …

Cds/Cdte Thin Film Solar Cells With Zinc Stannate Buffer Layer, Srilatha Bapanapalli

USF Tampa Graduate Theses and Dissertations

CdS/CdTe solar cell performance and reproducibility can be improved by integrating a ZTO buffer layer, which interdiffuses into the CdS layer during device fabrication. Reducing the thickness of CdS layer improves the QE in the blue spectral region without affecting the device performance. This buffer layer is expected to prevent the formation of localized TCO/CdTe junction during high temperature processing.

The CdS/CdTe Solar Cell was modified by introducing ZTO as a buffer layer between the window layer (CdS) and the absorber layer (CdTe). Studies were performed on different varying ZTO processing parameters like (a) Zn/Sn atomic ratios during sputtering process, …

Cadmium Zinc Telluride Solar Cells By Close Spaced Sublimation, Madhan Raj Ramalingam

USF Tampa Graduate Theses and Dissertations

Cadmium Zinc Telluride (Cd_xZn_1-xTe or CZT) is a ternary semiconductor with a tunable bandgap of 1.44-2.26 eV. Solar cells with efficiencies of 20% or higher can be achieved by using a tandem solar cell structure which consists of a top cell and a bottom cell connected in series. In this kind of a structure, the light passes through the top cell first which has a wider bandgap to absorb light of shorter wavelengths and the remaining light passes through the bottom cell with a lower bandgap to absorb light of higher wavelengths. For a tandem cell …

Fpga-Based Implementation Of Concatenative Speech Synthesis Algorithm, Praveen Kumar Bamini

USF Tampa Graduate Theses and Dissertations

The main aim of a text-to-speech synthesis system is to convert ordinary text into an acoustic signal that is indistinguishable from human speech. This thesis presents an architecture to implement a concatenative speech synthesis algorithm targeted to FPGAs. Many current text-to-speech systems are based on the concatenation of acoustic units of recorded speech. Current concatenative speech synthesizers are capable of producing highly intelligible speech. However, the quality of speech often suffers from discontinuities between the acoustic units, due to contextual differences. This is the easiest method to produce synthetic speech. It concatenates prerecorded acoustic elements and forms a continuous speech …