Electrical and Computer Engineering Commons^™

Excitation Of Whispering Gallery Modes In Glass Microspheres Using Optical Fiber Couplers, Sudha Sneha Devarakonda

Masters Theses

"This research is a study conducted on the excitation of whispering gallery modes (WGM) in small micron-scale glass spheres. Optical WGM may be represented by a light wave that propagates along the surface of the sphere and reaches back itself in phase at specific wavelengths. Due to this, very high intensities of light with narrow line widths circulate in the microspheres contributing to high Q factor. The evanescent field of an optical waveguide is used to resonantly stimulate the WGM.

The WGM excitation in fused silica spheres was demonstrated in the laboratory with 60% coupling efficiency. Tapered optical fibers were …

"In Situ" Printed Circuit Board Material Extraction Procedure With Conductor Surface Roughness Study, Amendra Koul

Masters Theses

"Analysis of printed circuit board (PCB) behavior in a wide frequency range from tens MHz to at least 40 GHz is very important for modern high-speed digital design and assuring for signal integrity (SI). this analysis includes preliminary evaluation of per-unit-length parameters of the PCB transmission line and transmission line characteristics, such as propagation and attenuation constants, and also extraction of these parameters from measurements on real test vehicles. This thesis describes an impedance calculator tool, which can substantially speed up PCB design, and the second topic considered in this work is characterization of dielectric parameters of substrates of printed …

Audio Watermarking Using Transformation Techniques, Rajkiran Ravula

LSU Master's Theses

Watermarking is a technique, which is used in protecting digital information like images, videos and audio as it provides copyrights and ownership. Audio watermarking is more challenging than image watermarking due to the dynamic supremacy of hearing capacity over the visual field. This thesis attempts to solve the quantization based audio watermarking technique based on both the Discrete Cosine Transform (DCT) and Discrete Wavelet Transform (DWT). The underlying system involves the statistical characteristics of the signal. This study considers different wavelet filters and quantization techniques. A comparison is performed on diverge algorithms and audio signals to help examine the performance …

Quantification Of Energy Intake Using Food Image Analysis, Sertan Kaya

LSU Master's Theses

Obtaining real-time and accurate estimates of energy intake while people reside in their natural environment is technically and methodologically challenging. The goal of this project is to estimate energy intake accurately in real-time and free-living conditions. In this study, we propose a computer vision based system to estimate energy intake based on food pictures taken and emailed by subjects participating in the experiment. The system introduces a reference card inclusion procedure, which is used for geometric and photometric corrections. Image classification and segmentation methods are also incorporated into the system to have fully-automated decision making.

Modeling And Analysis Of Radial Flux Toroidally Wound Twin Rotor Permanent Magnet Motor, Ravi Kishore Pratapa

LSU Master's Theses

The main objective of current thesis is the study of Radial Flux Twin Rotor Permanent Magnet (RFTWTRPM) motor. The tasks were to review the literature about RFTWTPM motors and model the motor using Finite Element Method Magnetics (FEMM 4.0). Later the performance of RFTWTRPM motor as a brushless dc motor was analyzed by using MATLAB/SIMULINK package. To find the electrical and mechanical parameters of the RFTWTRPM motor, the rotor and stator dimensions of the motor were firstly optimized using linear FEMM model of the motor. The optimized dimensions were used to construct the cylindrical FEMM model. This model was later …

The Weakening Of Branch Predictor Performance As An Inevitable Side Effect Of Exploiting Control Independence, Christopher Joseph Michael

LSU Doctoral Dissertations

Many algorithms are inherently sequential and hard to explicitly parallelize. Cores designed to aggressively handle these problems exhibit deeper pipelines and wider fetch widths to exploit instruction-level parallelism via out-of-order execution. As these parameters increase, so does the amount of instructions fetched along an incorrect path when a branch is mispredicted. Many of the instructions squashed after a branch are control independent, meaning they will be fetched regardless of whether the candidate branch is taken or not. There has been much research in retaining these control independent instructions on misprediction of the candidate branch. This research shows that there is …

Integrating Lattice Space-Time Codes Of Highest Rank And Multiplexing Over Rayleigh Fading Channels, Vamshi Krishna Samudrala

LSU Master's Theses

In this thesis, we consider the problem of finding an optimal combination of multiplexing and space-time coding over a MIMO array when a transmitter has a prior knowledge about correlation. Some existing work in this area used multiplexing and space-time coding methods as a technique to achieve capacity over a MIMO wireless channel. In this work, we consider a 2x2 lattice space-time code of highest rank and multiplex it over a MIMO system to improve the bit error rate performance. The main focus of this thesis is to address the problem of switching between spatial multiplexing and space-time coding to …

Modeling Pm Rotary-Linear Motors With Twin-Stator Using 3d Femm, Oleksandr Dobzhanskyi

LSU Master's Theses

A rapid growth of automatization nowadays requires electric machines to be adjusted to any technological process. Therefore, a need in machines with two degrees of mechanical freedom (TDMF), which can operate rotationally and linearly, is relatively large. This thesis is directed on the design and study of performance of PM (permanent magnet) rotary-linear synchronous motors with twin-armature as a new type of electric machines which can perform linear, rotational and helical movements. Three stator versions are considered, namely: stator with rotary and linear armatures, two rotary armatures, and two linear armatures. The rotors have PMs skewed with respect to the …

Carbon Nanotube Interconnect Modeling For Very Large Scale Integrated Circuits, Yao Xu

LSU Doctoral Dissertations

In this research, we have studied and analyzed the physical and electrical properties of carbon nanotubes. Based on the reported models for current transport behavior in non-ballistic CNT-FETs, we have built a dynamic model for non-ballistic CNT-FETs. We have also extended the surface potential model of a non-ballistic CNT-FET to a ballistic CNT-FET and developed a current transport model for ballistic CNT-FETs. We have studied the current transport in metallic carbon nanotubes. By considering the electron-electron interactions, we have modified two-dimensional fluid model for electron transport to build a semi-classical one-dimensional fluid model to describe the electron transport in carbon …