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Testing Chromatic Adaption Models Using Object Colors, Elizabeth Pirrotta Mar 1994

Testing Chromatic Adaption Models Using Object Colors, Elizabeth Pirrotta

Theses

The objective of this research was to determine which published chromatic adaptation model performed best under a single set of conditions. Previous research has been conducted to study chromatic adaptation, develop models and to indirectly test those models. This research directly tested the performance of these models using printed, simple-field, object colors through a successive-ganzfe/cf haploscopic, paired comparison, matching experiment. The chromatic adaptation models tested were CIELAB, CIELUV, Fairchild '91, Hunt '91, LABHNU2, Nayatani et al. '90 and von Kries. The test illuminant was incandescent at 231 lux. Model predictions were calculated for the reference simulated daylight at 2,396 lux. …


Type Pictures: The Life And Work Of Albert Schiller, Michael Keefe Feb 1994

Type Pictures: The Life And Work Of Albert Schiller, Michael Keefe

Theses

None provided.


Plasma Modification Of Poly(Ester Sulfonic) Acid Aniomoneric Membranes, Linda Slapelis Feb 1994

Plasma Modification Of Poly(Ester Sulfonic) Acid Aniomoneric Membranes, Linda Slapelis

Theses

The effect of variations in plasma parameters on the fluorination, degradation, and etching of poly(ester sulfonic) acid (AQ55) anionomeric membranes was examined. The determination of how the plasma gas composition, power, proximity of the sample to the glow, and time of exposure could be used to maximize surface fluorination and minimize degradation of polymer films is discussed. Membrane surfaces were characterized using contact angles, SEM, gravimetric analysis, DSC, FTIR/MIR, and XPS. These techniques aided in the determination of changes in surface energy, surface topography, sample weight, bulk property, and the identification and quantification of chemical functionalities produced at the AQ55 …


Daedalus: Cockpit Flight Management System, Jeffrey Paris Feb 1994

Daedalus: Cockpit Flight Management System, Jeffrey Paris

Theses

The purpose of this thesis was to design a portable computer-based flight management system for general aviation pilots.


Rapid Thermal Processing Of Polysilicon Emitter Transistors, Diane Mauersberg Feb 1994

Rapid Thermal Processing Of Polysilicon Emitter Transistors, Diane Mauersberg

Theses

The recent developments in rapid thermal processing in the past several years have shown it to have much potential in achieving full dopant activation of implanted junctions with a limited amount of junction depth movement. Its application to polysilicon emitter transistors allows for the formation of very shallow emitter-base junctions and narrow base widths with far greater activation capability than conventional furnace processes. A process for polysilicon emiter transistors utilizing rapid thermal annealing has been developed. Furnace processing at 875 C; and rapid thermal processing for 20 seconds at 950 C, 1000 C, and 1050 C was performed to anneal …


Vhdl Modeling And Design Of An Asynchronous Version Of The Mips R30000 Microprocessor, Paul Fanelli Feb 1994

Vhdl Modeling And Design Of An Asynchronous Version Of The Mips R30000 Microprocessor, Paul Fanelli

Theses

The goal of this thesis is to demonstrate the feasibility of converting a synchronous general purpose microprocessor design into one using an asynchronous methodology. This thesis is one of three parts that details the entire design of an asynchronous version of the MIPS R3000 microprocessor. The design includes the main architectural features of the R3000: the 5-stage pipeline, the thirty-two 32-bit register bank, and the 32-bit address and data paths. To limit the size of the project, the memory and coprocessor are excluded. Therefore, this design has implemented the entire set of instructions from the original synchronous version with the …


A Hardware Approach To Neural Networks Silicon Retina, Arif K. Golwalla Feb 1994

A Hardware Approach To Neural Networks Silicon Retina, Arif K. Golwalla

Theses

The primary goal of this thesis was to emulate the function of the biological eye in silicon. In both neural and silicon technologies, the active devices occupy approximately 2 percent of the space, wire fills the entire remaining space. The silicon retina was modeled on the distal portion of the vertebrate retina. This chip generates, in real time, outputs that correspond directly to signals observed in the corresponding levels of the biological retinas. The design uses the principles of signal aggregation. It demonstrates a tolerance for device imperfection that is characteristic of a collective system. The digital computer is extremely …


Delicate Intimacies, Jeanne Marie Ferraro Feb 1994

Delicate Intimacies, Jeanne Marie Ferraro

Theses

None provided.


Interiors, Dana Ranke Feb 1994

Interiors, Dana Ranke

Theses

None provided.


Patient, Disease And Surgical Parameters In The Prediction Of Histologic Nodes And Recurrence Of Squamous Cell Carcinoma, Adolfo A. Ferreira Jan 1994

Patient, Disease And Surgical Parameters In The Prediction Of Histologic Nodes And Recurrence Of Squamous Cell Carcinoma, Adolfo A. Ferreira

Theses

This research explores the impact of a variety patient, disease and lesion parameters upon the probability of post surgery recurrence of squamous cell carcinoma and the involvement of histologic nodes. It was found that parameters such as number of nodes, Lymph Vascular Space Invasion (LVS), figo stage, growth rate and host response as well as tumor thickness, depth of invasion and lesion size are good predictors. Other parameters such as cell type and condylomas were found to correlate minimally with recurrence and histologic nodes. Surgical parameters such as surgical margin and distance surgical margin were found to have poor correlation …


Implementation Of An Automatic Mapping Tool For Massively Parallel Computing, Ajitha Gadangi Jan 1994

Implementation Of An Automatic Mapping Tool For Massively Parallel Computing, Ajitha Gadangi

Theses

In this thesis, an implementation of a generic technique for fine grain mapping of portable parallel algorithms onto multiprocessor architectures is presented. The implemented mapping algorithm is a component of Cluster-M. Cluster-M is a novel parallel programming tool which facilitates the design and mapping of portable softwares onto various parallel systems. The other components of Cluster-M are the Specifications and the Representations. Using the Specifications, machine independent parallel algorithms are presented in a "clustered" fashion specifying the concurrent computations and communications at every step of the overall execution. The Representations, on the other hand, are a form of clustering the …


Investigation Of Reduced Hypercube (Rh) Networks : Embedding And Routing Capabilities, Michalis A. Sideras Jan 1994

Investigation Of Reduced Hypercube (Rh) Networks : Embedding And Routing Capabilities, Michalis A. Sideras

Theses

The choice of a topology for the interconnection of resources in a distributed-memory parallel computing system is a major design decision. The direct binary hypercube has been widely used for this purpose due to its low diameter and its ability to efficiently emulate other important structures. The aforementioned strong properties of the hypercube come at the cost of high VLSI complexity due to the increase in the number of communication ports and channels per node with an increase in the total number of nodes. The reduced hypercube (RH) topology, which is obtained by a uniform reduction in the number of …


Study Of The Leaching Of Pentachlorophenol From Treated Utility Poles, Jingyi Zhang Jan 1994

Study Of The Leaching Of Pentachlorophenol From Treated Utility Poles, Jingyi Zhang

Theses

Pentachlorophenol ( PCP ) has been used as a preservative in wood industry over 40 years. If new regulations are passed, the disposal of used treated utility poles in landfills could be restricted because of the toxic properties of PCP. This study was undertaken to provide a better understanding of the rates and mechanisms of leaching of PCP from these poles.

Following the initial analytical method development for PCP determination, a study was done to apply and validate the method in a leaching characteristics study of PCP from Douglas Fir and Southern Pine.

The major factors which influence the leaching …


Performance Modeling Of High Data Rate Ring Networks Using Stochastic Petri Nets, Le Zhong Jan 1994

Performance Modeling Of High Data Rate Ring Networks Using Stochastic Petri Nets, Le Zhong

Theses

This thesis has proposed a performance analysis method for Carrier Sensing Multiple Access Ring Network (CSMA) based on Petri net methodologies. The method can offer more accurate results than traditional queuing methods, but less than simulation results. In the CSMA network access protocol is studied in this thesis, when a passing message is detected by a station, it stops transmitting immediately in order to avoid a collision.

A generalized stochastic Petri nets model is made first, then the SPNP package is used to do the analysis. The analysis results show that even at a very heavy load fraction of near …


Design Of An Autonomous Vehicle System, Fritz Gerald Momplaisir Jan 1994

Design Of An Autonomous Vehicle System, Fritz Gerald Momplaisir

Theses

With advances in electronics, mobile vehicles are becoming more and more sophisticated. The Potential applications of AGVs are numerous an range from a material handling system for the factory floor to an intelligent wheel chair for the handicapped. The design of these vehicles, however, remains a difficult task. Even when the machine is given precise information about its environment, the fact that it is never free of noise further complicate the situation. One of the goals of an AGV project is to design a robust system that will operate efficiently in the presence of different sources of noise.

The scientific …


Authentication For Mobile Computing, Andreas Keppler Jan 1994

Authentication For Mobile Computing, Andreas Keppler

Theses

Host mobility is becoming an increasingly important feature with the recent arrival of laptop and palmtop computers, the development of wireless network interfaces and the implementation of global networks. Unfortunately, this mobile environment is also much more vulnerable to penetration by intruders. A possible means of protection can be authentication. This guarantees the identity of a communication peer.

This thesis studies the constraints imposed on the mobile environment with respect to authentication. It compares the two prevailing authentication mechanisms, Kerberos and SPX, and tries to make suggestions of how a mechanism can be adapted to the mobile environment.


Fabrication Of Micron-Sized Mirror/Cantilever Silicon Devices For Crosspoint Switching Arrays, Yasser A. Abdel-Aziez Jan 1994

Fabrication Of Micron-Sized Mirror/Cantilever Silicon Devices For Crosspoint Switching Arrays, Yasser A. Abdel-Aziez

Theses

This thesis describes the fabrication of micron-sized vertical mirrors at the end of horizontal cantilevers, that are electrostatically controlled. The mirrors, 40x 40 μm with thicknesses of 1.5-6 μm, were made by using the etch resistance to 40% KOH etchant of <111> planes and oxide stripes. The cantilever beams, 100 to 350 μm long and 0.44 to 0.81 μm thick, were fabricated using the etch resistance of heavily doped boron layers to 10% KOH at 50 °C. Two technologies to introduce the boron layers were investigated. The ion implantation approach was based on thick oxide/photoresist masking. A maximum doping of 2.5 …


Design And Implementation Of Ipis : An X-Window Based Image Processing Interactive System, Eduardo Morales Jan 1994

Design And Implementation Of Ipis : An X-Window Based Image Processing Interactive System, Eduardo Morales

Theses

Most of image processing systems are based on command line functions or can only display one image at a time. This is a serious inconvenience for those who need an interactive system session or want to compare two images processed by different techniques at the same time.

The system was designed with these problems in mind. It is able to display the processed image right after an operation and to display several images simultaneously, making it simple to compare techniques. The system was also created with the purpose to be used in an academic environment. Its structured design makes it …


A Hybrid Low Bit-Rate Video Codec Using Subbands And Statistical Modeling, Ferhat Cakrak Jan 1994

A Hybrid Low Bit-Rate Video Codec Using Subbands And Statistical Modeling, Ferhat Cakrak

Theses

A hybrid low bit-rate video codes using subbands and statistical modeling is proposed in this thesis. The redundancy within adjacent video frames is exploited by motion estimation and compensation. The Motion Compensated Frame Difference (MCFD) signals are decomposed into 7 subbands using 2-D dyadic tree structure and separable filters. Some of the subband signals are statistically modeled by using the 2-D AR(1) technique. The model parameters provide a representation of these subbands at the receiver side with a. certain level of error. The remaining subbands are compressed employing a classical waveform coding technique, namely vector quantization (VQ).

It is shown …


External Cavity Laser Power Stabilizer, Jie Ding Jan 1994

External Cavity Laser Power Stabilizer, Jie Ding

Theses

In this thesis, we want to design a stabilizer which does not depend on laser source--with external cavity.

In the first part of the thesis ( Chapter 2 and 3 ), we discuss the wave propagation in crystals and the modulation of optical radiation. From the main two types electro-optic modulations, Phase Modulation and Transverse Modulation, we know that the transverse modulation shows an increase in the frequency limit or useful crystal length of (1-c0/ncm)-1, and we will use this type modulation in this thesis.

The second part of the thesis is the procedure of design and experiment. …


Three Dimensional Diaphragm Simulation Model For The Relationship Of The Tension, Pressure And Shape, Zhangming He Jan 1994

Three Dimensional Diaphragm Simulation Model For The Relationship Of The Tension, Pressure And Shape, Zhangming He

Theses

Weakness of inspiratory muscles is a major cause of respiratory failure. There are many clinical circumstances in which it may occur. The diaphragm is a major respiratory muscle. It has been difficult to quantify its shape, curvature and length.

To solve this question, a three dimensional diaphragm equation was derived on the, assumption that the diaphragm is only attached at its periphery to the rib cage and the abdomen is filled with fluid. Computer programs were developed to fit the equation to the diaphragm contours obtained from plane X rays.

The results indicate that the ratio of transdiaphragmatic pressure to …


Calibration Of Photoluminescence Experiment, Chihchuan Daniel Lee Jan 1994

Calibration Of Photoluminescence Experiment, Chihchuan Daniel Lee

Theses

Photoluminescence in a semiconductor at room temperature is quite difficult to distinguish from the many nonlasing optical lines from the laser, therefore, a blank test is very important. In so doing, the noises of the detector has to be taken into account. The calibration, however, mainly depends on the detector and is less dependent on other components. Instead of using black-body radiation light source and pyroelectric detector, we use globar lamp and PbS detector; because of the difficulty in the former case in doing alignment of optical path (invisible) and operating at a lower signal level from the detector. The …


Sulfuric Acid Resistance Of Fly Ash Mortar, Walairat Bumrongjaroen Jan 1994

Sulfuric Acid Resistance Of Fly Ash Mortar, Walairat Bumrongjaroen

Theses

Crown corrosion of concrete pipe and its subsequent repair is a topic much discussed in recent years. Present protective methods have not worked effectively. Due to its properties and its low cost, fly ash was used as a cement replacement of mortar to investigate its sulfuric acid resistance.

Different types and different percentages of fly ashes were mixed with and without admixtures including microsilica, and superplasticizer. The main parameters investigated included the chemical compounds, the fineness and the volume of fly ash. 2"x2" cubes were immersed in a 10% sulfuric acid pond. The weight of each cube was determined continuously …


Geotechnical Characterization Of Water Treatment Plant Residuals, Zhengyuan Xia Jan 1994

Geotechnical Characterization Of Water Treatment Plant Residuals, Zhengyuan Xia

Theses

Evaluation of engineering properties of water treatment plant (WTP) residuals is a critical part in predicting their behaviors in monofills. In this study, ten WTP residual samples were collected from ten water treatment plants across the United States. Their general chemical/physical and geotechnical properties including liquid and plastic limits, compaction) shear strength, permeability and durability characteristics were determined.

It was observed that the geotechnical properties of WTP residuals are influenced by various factors such as mineral particle composition, organic content, type and amount of chemical additives) and time of aging, etc. Based on this study, the behavior of WTP residual …


Concurrent Use Of Two Programming Tools For Heterogeneous Supercomputers, Javier G. Vasquez Jan 1994

Concurrent Use Of Two Programming Tools For Heterogeneous Supercomputers, Javier G. Vasquez

Theses

In this thesis, a demostration of the heterogeneous use of two programming paradigms for heterogeneous computing called Cluster-M and HAsC is presented. Both paradigms can efficiently support heterogeneous networks by preserving a level of abstraction which does not include any architecture mapping details. Furthermore, they are both machine independent and hence are scalable. Unlike, almost all existing heterogeneous orchestration tools which are MIMD based, HAsC is based on the fundamental concepts of SIMD associative computing. HAsC models a heterogeneous network as a coarse grained associative computer and is designed to optimize the execution of problems with large ratios of computations …


Design And Implementation Of Fuzzy Logic Controller For A Process Control Application, Sujit S. Nerurkar Jan 1994

Design And Implementation Of Fuzzy Logic Controller For A Process Control Application, Sujit S. Nerurkar

Theses

Many industrial applications of fuzzy logic control have been reported. This thesis studies and reports the problems associated with the Heat-exchanger temperature control via conventional PID control implemented with Programmable Logic Controllers (PLC) and provides an example of design and implementation of fuzzy logic controllers (FLC's) for a Heat exchanger in a Water for Injection (WFI) system.

After a basic FLC was designed and tested, it is shown how its rule base evolved to achieve superior performance by utilizing additional low-cost sensing information in the process and its environment. A method for the implementation of FLC's into the existing PLC …


Photoluminescence Study Of Gallium Arsenide, Aluminum Gallium Arsenide, And Gallium Antimonide Thin Films Grown By Metalorganic Chemical Vapor Deposition, John Mark Koons Jan 1994

Photoluminescence Study Of Gallium Arsenide, Aluminum Gallium Arsenide, And Gallium Antimonide Thin Films Grown By Metalorganic Chemical Vapor Deposition, John Mark Koons

Theses

The photoluminescence produced by four MOCVD grown epitaxial thin film samples was studied to give insight into sample quality. The four samples under this study were GaAs on a GaAs substrate, Al.25Ga.75As on a GaAs substrate, Al.30Ga.7OAs on a GaAs substrate, and GaSb on a GaSb substrate. Excitation was achieved through the use of the 514.0 nm line of an argon ion laser, and sample cooling was attained by use of a cryostat cooler using helium gas to attain a low temperature limit of 10°K. The GaAs and Al.30Ga.7O …


Sensitivity Analysis In Energy Responsive Design, Bratati Biswas Jan 1994

Sensitivity Analysis In Energy Responsive Design, Bratati Biswas

Theses

Energy responsive design involves the conscious use of climatic elements and natural processes in the design of spaces. Buildings are designed to react favorably with the environment to produce balanced comfort conditions. Passive solar building design utilizes this concept to heat or cool a building by natural means. In this approach, building components and materials are articulated to make maximum use of solar radiation and climatic elements producing energy responsive spaces.

The purpose of this research is to help designers to design with energy in mind. Energy related decisions are required during conceptual design and is not an add-on item …


An Integrated Mrp And Finite Scheduling System To Derive Detailed Daily Schedules For A Manufacturing Shop, Sita D. Nathan Jan 1994

An Integrated Mrp And Finite Scheduling System To Derive Detailed Daily Schedules For A Manufacturing Shop, Sita D. Nathan

Theses

Many companies rely on Material Requirements Planning (MRP) to support their Production Scheduling and Control (PS&C) functions. Since MRP does not provide a detailed shop floor schedule, these users have to implement either a third party procedure or an internally developed procedure for shop floor controls. In this thesis we consider a class of user shops which are characterized by the following features:

  • Homogenous machines, that is all machines can produce all products.

  • Each product requires a setup, but several products may have a common setup.

  • MRP requirements are specified on a weekly basis while actual requirements are specified on …


Pyrolysis And Oxidation Reaction Of 1,2, Dichloroethylene In Ar; Ar And Ch4; Ar, Ch4 And O2 Mixtures, Byung Ik Park Jan 1994

Pyrolysis And Oxidation Reaction Of 1,2, Dichloroethylene In Ar; Ar And Ch4; Ar, Ch4 And O2 Mixtures, Byung Ik Park

Theses

The thermal reaction of trans-1,2-dichloroethylene (DCEE) in methane and oxygen mixtures in Ar bath gas has been studied in 10.5 mm I.D. tubular flow quartz reactors at I atmosphere pressure, isothermal temperature between 575°C and 1000°C, and times of 0.3 to 2.0 seconds.

The thermal reaction of trans-1,2-dichloroethylene in the gas phase proceeds via unimolecular HCI elimination under the reaction condition of the present experiments. The chain branching C-Cl bond fission reaction is expected to become important at the higher temperature, competing With the HCI elimination.

The decay trans- 1,2- dichloroethylene, intermediates and final product distributions varied in the absence …