Engineering Commons^™

Implementing Ray Tracing Algorithm In Parallel Environment, Tjah Jadi

Dissertations and Theses

Ray tracing is a very popular rendering algorithm in the field of computer graphics because it can generate highly-realistic images from three-dimensional models. Unfortunately, the computational cost is very expensive. To speed up the rendering process we present both static and dynamic scheduling (balancing) strategies for a multiprocessor system. Hence, the load balancing among the processors is the most important problem in parallel processing. The implementation of the algorithm is based on a modified octree structure.

A Cmos Circuit Generator Using Differential Pass Transistors For Implementing Boolean Functions, Rabe'eh Mahooti

Dissertations and Theses

This study uses differential pass transistor methodology for implementing and evaluating Boolean functions. The main goal is investigation of CMOS and nMOS approaches in pass transistor logic design. Pass-transistor logic is most effective in the implementation of Boolean functions when the vectors are in the same format. It has been demonstrated that nMOS pass transistor logic driven by a control signal voltage above the V_dd level offers a significant improvement in speed. nMOS pass transistorsalso offer less area consumption in comparison to the CMOS approach.

The philosophy developed here has been used in the design of a program for …

Dc-Excited Cw Co₂ Metal Waveguide Laser, Fahad Saleh Al-Mashaabi

Dissertations and Theses

A novel design for a DC excited cw CO₂ metal waveguide laser has been developed in which a slotted hollow-cathode in a transverse discharge also doubles as a metal waveguide. This design has been implemented in a compact design that produces up to 1 watt of cw, 10.6 μm radiation. The discharge characteristics, laser gain and laser output has been studied as functions of various discharge parameters. The advantages of the new transverse discharge of the slotted hollow cathode geometry include low voltage, positive impedence and high optical gain. Overall efficiency is comparable with those of conventional longitudinal CO …

A New General Purpose Systolic Array For Matrix Computations, Hai Van Dinh Le

Dissertations and Theses

In this thesis, we propose a new systolic architecture which is based on the Faddeev's algorithm. Because Faddeev's algorithm is inherently general purpose, our architecture is able to perform a wide class of matrix computations. And since the architecture is systolic based, it brings massive parallelism to all of its computations. As a result, many matrix operations including addition, multiplication, inversion, LU-decomposition, transpose, and solutions to linear systems of equations can now be performed extremely fast. In addition, our design introduces several concepts which are new to systolic architectures:

- It can be re-configured during run time to perform different …

Voltage Controlled Resistance Model For Mos Transistors, Joey Zong-Yi Jia

Dissertations and Theses

The voltage controlled resistance model is developed for a reliable MOS transistor resistance mapping. The model includes both system and local parameters, and incorporates the effect of rise and fall time variations on the gate delay. MOS transistor resistance mapping is applied in logic simulation and timing verification. Also, it can be used in automatic transistor sizing and critical path analysis.

A Lagrangian For A System Of Two Dyons, Rainer Georg Thierauf

Dissertations and Theses

Maxwell's equations for the electromagnetic field are symmetrized by introducing magnetic charges into the formalism of electrodynamics. The symmetrized equations are solved for the fields and potentials of point particles. Those potentials, some of which are found to be singular along a line, are used to formulate the Lagrangian for a system of two dyons (particles with both electric and magnetic charge). The equations of motion are derived from the Lagrangian. It is shown that the dimensionality constants k and k * , which we r e introduced to define the units of the electromagnetic fields, have to be equal …

Logic Design Using Programmable Logic Devices, Loc Bao Nguyen

Dissertations and Theses

The Programmable Logic Devices, PLO, have caused a major impact in logic design of digital systems in this decade. For instance, a twenty pin PLO device can replace from three hundreds to six hundreds Transistor Transistor Logic gates, which people have designed with since the 60s. Therefore, by using PLD devices, designers can squeeze more features, reduce chip counts, reduce power consumption, and enhance the reliability of the digital systems.

This thesis covers the most important aspects of logic design using PLD devices. They are Logic Minimization and State Assignment. In addition, the thesis also covers a seldomly used but …

Safety Related Model And Studies Of Trojan Nuclear Power Plant Electrical Distribution System, Hamidreza Sharifnia

Dissertations and Theses

The most important requirement for running a nuclear power plant safely is having a reliable safety system, especially during the emergency shutdown condition. For performing a scrutiny load flow and voltage drop study a detailed and comprehensive electrical model for the emergency electrical distribution system of the Trojan Nuclear Power Plant has been developed. This model includes the representation of the transformers, circuit breakers, motors, cables and load data from 4160 volts level down to the individual 480 volts loads.

Two Dimensional And Three Dimensional Path Planning In Robotics, Hyun Suk Kim

Dissertations and Theses

A methodology for 2D and 3D collision free path planning algorithm in a structured environment is presented. The isolated free convex areas are represented as a nodes in a graph, and a graph traversal strategy that dynamically allocates costs to graph path is used. Modification of the algorithm for small computational time and optimality is discussed. The 3D path planning is done in the three orthogonal two-dimensional projections of a 3D environment. Collision checking to increase the optimality for 3D paths is done in each of the three orthogonal two-dimensional subspaces.

Off-Axis Multimode Light Beam Propagation In Tapered Lenslike Media Including Those With Spatial Gain Or Loss Variation, Anthony Alan Tovar

Dissertations and Theses

The propagation of light beams in inhomogeneous dielectric media is considered. The derivation begins with first principles and remains general enough to include off-axis asymmetric multimode input beams in tapered lenslike media with spatial variations of gain or loss. The tapering of lenslike media leads to a number of important applications. A parabolic taper is proposed as a model for a heated axially stretched fiber taper, and beams in such media are fully characterized. Other models are proposed by the concatenation of a parabola with other taper functions.