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Development Of A Computer Model To Track Water Droplet Trajectories As Related To Aircraft Icing, Satyen G. Harve Sep 1984

Development Of A Computer Model To Track Water Droplet Trajectories As Related To Aircraft Icing, Satyen G. Harve

Theses

In order to be able to predict the local ice accretion rate, or the icing profile on any surface it is neccessary that a model be available, which helps in determining the local impingement values of water droplets on the object. Two models have been developed. One model determines the potential and the velocity field around any arbitrary object. The second model determines the trajectory of the water droplets in the presence of a potential field. The two models have been combined to form a general trajectory model capable of tracking water droplet trajectories around any arbitrary object. The object …


Enhancement Of The Integrated Mechanisms Program (Imp) By Addition Of Graphic Output, Anil Parsaram Hingorani Sep 1984

Enhancement Of The Integrated Mechanisms Program (Imp) By Addition Of Graphic Output, Anil Parsaram Hingorani

Theses

The Integrated Mechanisms Program (IMP) is enhanced to include the capability of graphic output of simple mechanisms. The subroutines available in the graphics package GP-10 are used. The output consists of a drawing of the mechanism at its initial position and for every position for which the analysis is done. In addition, a graph of velocity and/or acceleration against the angle of the driving link may be plotted. There are limitations. The output of the mechanism represents only prismatic joints by a different symbol. It is represented by a rectangle and the symbol of the fixed link. All the other …


Optimization Of The Sputtering Technology For Preparation Of Hg1-[Subscript X] Cd[Subscript X] Te Heterojunction Diodes, Kyriacos Kokkinos Sep 1984

Optimization Of The Sputtering Technology For Preparation Of Hg1-[Subscript X] Cd[Subscript X] Te Heterojunction Diodes, Kyriacos Kokkinos

Theses

The deposition of (Hg1-xCdx)Te onto Si and (Hg1-yCdy)Te (x>y) substrates by rf triode sputtering was studied. Ionized mercury vapor, in the 0.6 to 1.2 micron pressure range, was used to bombard pressed-powder targets, consisting of HgTe and CdTe particles, with effective target x value of 0.3, 0.35, and 0.4. The sputtering procedure, parameters, and system were modified to optimize film characteristics. Higher substrate temperature (270°C) was required to obtain metallic gray films with x>0.3. With substrate temperatures less than 270°C and deposition rates 0.5-1.0 micron per hour the films were …


Japanese Management Techniques And Its Transition To Taiwan, Shih-Tung Shu Sep 1984

Japanese Management Techniques And Its Transition To Taiwan, Shih-Tung Shu

Theses

Japan's success, as measured by a vertically increasing balance-of-payments surplus, has created serious issues between Japan and other industrial democracies. It has created fears about the economic superpower status of Japan. On the other hand, because of this very success in coping with worldwide economic problems and in sustaining its export drive, Japan's unique style of managenemt has attracted a great deal of attention. As the Japanese have begun to demonstrate on ability to transfer their management style to the U. S. and other western countries, Japanese management and its transferability continue to be a subject of special interest in …


Prefeasibility Study Of Flexible Manufacturing System, Patrice Gerault Sep 1984

Prefeasibility Study Of Flexible Manufacturing System, Patrice Gerault

Theses

Most major companies over the world are or intend to go into Flexible Manufacturing System. But, FMS is not as easy to implement as most cf the other equipments. It affects the whole company and careful studies must be done before parchasing it.

After a description of this new system, this paper reviews the effects introduced by FMS and the alements of savings or surcosts in comparison to conventional systems ; but no numerical evaluations are stated.

This paper gives a frame to any company which wants to undertake a prefeasibility study.


X-Ray Fluorescence Spectroscopic Analysis Of Coal Ash, George Patrick Watson Sep 1984

X-Ray Fluorescence Spectroscopic Analysis Of Coal Ash, George Patrick Watson

Theses

Several coal ashes and prepared mixtures were analyzed by x-ray fluorescence spectroscopy. Various techniques were studied to determine the most reliable procedure for quantitatively estimating, from fluorescent peak intensities, the concentrations of seven major oxides typically present in the ash. These ashes were analyzed with only minimal sample preparation. In order to determine the self-consistency of the procedure, several mixtures of known composition were prepared containing the major elements present in an ash.

Because of inter-element absorption and enhancement effects, several computational techniques were used to calculate composition from spectrum peak intensities. The method that yielded the most accurate estimates …


Contaminant Transport Against A Slowly Moving Fluid : An Experimental Investigation, Surya Man Shakya Sep 1984

Contaminant Transport Against A Slowly Moving Fluid : An Experimental Investigation, Surya Man Shakya

Theses

Leachate migration into groundwater from leaking lagoons, hazardous waste sites, solid waste disposal sites, etc. has recently become a major cause of groundwater pollution. A possible solution to prevent leachate migration into groundwater is to create a negative hydraulic gradient toward the site. This can be achieved by installing two parallel slurry trench cut-offs around the perimeter of a leaking lagoon and by filling it with water. The water und-er the influence of positive hydraulic gradient will move toward the site and will finally find its way on the surface of the lagoon. Along with the flow of water, the …


Experimental Investigation Of Submerged, Turbulent, Array Of Air Jets Impinging On A Flat Plate, Samir Sethi Sep 1984

Experimental Investigation Of Submerged, Turbulent, Array Of Air Jets Impinging On A Flat Plate, Samir Sethi

Theses

Experimental investigation was carried out on the flow characteristics of a circular, submerged, turbulent, array of axisymmetric air jets impinging normally on a smooth, flat, square, lucite plate. Jets issuing from an array of circular nozzles 0.25 and 0.375 in. (0.635 and 0.9525 cm) in diameter were considered and nozzle exit Reynolds Number varied from 10,000 to 60,000.The ratio of nozzle center to center distance to the nozzle diameter, given by Cn/D, of 2 and 3 were considered. The jet velocity was not too high, such that at a Mach Number less than 0.3, the flow was still …


Computer Aided Design Of Optimum Structures, Sanjay M. Alexander Sep 1984

Computer Aided Design Of Optimum Structures, Sanjay M. Alexander

Theses

Techniques for the improvement of procedures for large scale structural synthesis are investigated. Considerable amount of research has been devoted to structural optimization. Yet as developments continue in this area, constant improvements in structural analysis methods, most of which are computationally demanding, tax the ability of existing optimization procedures to use the most powerful of the new analysis techniques effectively. This thesis presents optimization of structures modeled by classical discretized finite elements using the direct stiffness approach. The technioue presented here utilizes a Mathematical Programming (MP) method, which is based on Zoutendijk's feasible Direction Finding Problem (DFP). Modifications on Zoutendijk's …


Woodworking, Sculpture, And Industrial Design: Three Major Influences On My Work, Terrence Brian Cray Aug 1984

Woodworking, Sculpture, And Industrial Design: Three Major Influences On My Work, Terrence Brian Cray

Theses

None provided.


A Survey Of The Reading Interests Of The Middle School Student, Kathleen Irene Hettich Aug 1984

A Survey Of The Reading Interests Of The Middle School Student, Kathleen Irene Hettich

Theses

The purpose of this study was to determine the reading interests of middle school students ranging in age from 10 to 14 years. The middle school has grown tremendously in acceptance since its beginnings in the 1960's. Years of study, careful planning, and evaluation using pilot schools preceded the success of this new grouping of students, usually consisting of grades six, seven, and eight. However, one aspect of the middle school did not receive the attention it deserved. Little can be found in a review of research on student use of the middle school library. Studies were directed either to …


Application Of Least Square Cubic Splines To The Analysis Of Edges, Roland Walter Porth Aug 1984

Application Of Least Square Cubic Splines To The Analysis Of Edges, Roland Walter Porth

Theses

A technique using least square cubic splines was developed to obtain an estimate of the MTF from edge response measurements. By making specific assumptions concerning the general nature of edges to be analyzed, an optimized procedure was developed to fit noise free cummulative gaussian edges. The procedure was evaluated using simulated data from various spread function shapes and levels of additive noise. The spline technique produced MTF estimates which had less bias and lower variance than the commonly used derivative - transform technique. Due to the various constraints which can be imposed on the spline, least square cubic splines actually …


A Signal-To-Noise Ratio Analysis Of An Autoradiographic Image Enhancement Process, Donald R. Williams Aug 1984

A Signal-To-Noise Ratio Analysis Of An Autoradiographic Image Enhancement Process, Donald R. Williams

Theses

A signal-to-noise ratio(SNR) analysis of a S-35 thiourea autoradiographic image enhancement process incorporating subproportional bleaches is performed, with emphasis on diagnostic medical Imagery. Quantifying SNR through a spatial frequency definition of DQE and NEQ, these metrics were compared between donor and receiver-composite stages. While improvements in radiometric speed and gamma were noted in the receiver-composite, these gains were more than offset in a SNR sense by correspondingly lower MTF and higher Wiener spectrum values. As a result the donor's DQF_max of .30 exceeded that of the receiver-composite's DQE_max by 50%. Similarly, ImCXA the donor's NEQ_max exceeded that of the receiver …


Information Theoretic Metrics For The Assessment Of Digital Image-Tone Restored Images, Paul W. Melnychuck Aug 1984

Information Theoretic Metrics For The Assessment Of Digital Image-Tone Restored Images, Paul W. Melnychuck

Theses

Digital image-tone restoration is examined in terms of information theoretic-based measurements. The metrics illustrate the relative degree of restorability of a 6-stop underexposure range on Kodak Tri-X pan film. An image chain model is developed to account for the discrete nature of sampled images used in digital image processing. The model includes the major system components (from object to viewed image) from which the system signal-tonoise ratio is calculated. Quantization noise and clipping are treated as signal-dependent, additive noise sources, and are shown to play a major role in degrading restored images. Although the eye characteristics are not included in …


Simulation Of Particle Size Distribution In Continuous Emulsion Polymerization Through A Modified Population Balance Approach, Ying-Yuh Lu Jul 1984

Simulation Of Particle Size Distribution In Continuous Emulsion Polymerization Through A Modified Population Balance Approach, Ying-Yuh Lu

Theses

A detailed mathematical model for particle size distribution in continuous emulsion polymerization of styrene and vinyl acetate is proposed on the basis of the population balance in the presence of several kinetic and mass transfer processes. This study is limited to the Smith-Ewart case II, which assumes instantaneous free radical termination within polymer particles. Radical desorption mechanism from polymer particles is included in the model and the desorption rate is formulated from the diffusion theory which suggests that the rate coefficient should be inversely proportional to the surface area of polymer particles.


Spectral Method Of Color Conversion Filter Thickness Applied To Simulation Of Cie Illuminants, Paul Butterfield Jul 1984

Spectral Method Of Color Conversion Filter Thickness Applied To Simulation Of Cie Illuminants, Paul Butterfield

Theses

A spectral method of determining color conversion filter thickness is described. This method uses spectral data from system parameters to determine thickness. Optimization of the input distribution by varying bulb current is discussed. Using the spectral method of thickness variation, two CIE Illuminants, D55 and D65 were simulated. The simulators were measured for goodness of fit and showed a strong similarity with their respective simulators. Mean square deviations were calculated for each Illuminant and were 11.09 and 11.33 for D55 and D65 respectively.


The Visual Box, Candace Lorimer Jul 1984

The Visual Box, Candace Lorimer

Theses

Not Included


Diversion Of Force, Linda J. Moughemer Jul 1984

Diversion Of Force, Linda J. Moughemer

Theses

I intend to complete a body of work using the concept of diversion of force as a departure point. A paper which will include the organic and inorganic scientific references which have affected my thinking and visual imagery will accompany and support the studio work. Other sources which have aided my exploration of the subject will also appear in the written presentation.


A Quantitative Image Evaluation Study Of A Concurrent Photon Amplification Treated Emulsion, Konrad E. Kern Jul 1984

A Quantitative Image Evaluation Study Of A Concurrent Photon Amplification Treated Emulsion, Konrad E. Kern

Theses

A study was performed to evaluate the effect of concurrent photon amplification (CPA) on Kodak Tri-X Pan emulsion in regard to image quality. The study evaluated detective quantum efficiency (DQE), modulation transfer function (MTF), and information content (IC) as a function of exposure in a comparison between normal exposure and CPA. The results showed CPA to enhance image quality relative to normal exposure at very low exposure levels. As the exposure was increased, normally exposed images became comparable and then exceeded CPA exposures in image quality. The exposure level at which normal exposure became preferential was distinct with each image …


Geometry And Vision To Galen, Mario Biagioli Jul 1984

Geometry And Vision To Galen, Mario Biagioli

Theses

None provided.


Constructed Clothing: Fiber To Finish, Catherine Grota Sahlin Jul 1984

Constructed Clothing: Fiber To Finish, Catherine Grota Sahlin

Theses

None provided.


The Horse: Structure And Form In Nature, Karen Ackoff Jun 1984

The Horse: Structure And Form In Nature, Karen Ackoff

Theses

None provided.


Gesture And Attitude, Stephen Piper Jun 1984

Gesture And Attitude, Stephen Piper

Theses

I intend to explore, with a small format camera, people's gestures and physical attitudes and the way in which these are enhanced by their relationship to the environment.


Synthesis And Characterization Of Poly(Amide-Sulfonamides), Michael J. Amone Jun 1984

Synthesis And Characterization Of Poly(Amide-Sulfonamides), Michael J. Amone

Theses

Nine novel poly (amide-sulfonamides) having general structures 1-3 shown below, have been prepared utilizing low temperature solution polymerization. Variously substituted dianilines containing preformed sulfonamide linkages have been reacted with terephthaloyl chloride, isophthaloyl chloride and sebacyl chloride to yield polymer structures 1, 2 and 3 respectively.


A Microprocessor Based Hybrid System For Digital Error Correction, Peter H. Sohn Jun 1984

A Microprocessor Based Hybrid System For Digital Error Correction, Peter H. Sohn

Theses

The design of a microprocessor based hybrid system for digital error correction is presented. It is shown that such a system allows for implementation of several cyclic codes at a variety of throughput rates providing variable degrees of error correction depending on current user requirements. The theoretical basis for encoding and decoding of binary BCH codes is reviewed. Design and implementation of system hardware and software are described. A method for injection of independent bit errors with controllable statistics into the system is developed, and its accuracy verified by computer simulation. This method of controllable error injection is used to …


Characterization Of Tdi-Hema Homopolymer Prepared Via An Immiscible Solvent System. Synthesis And Investigation Of Oligodichloroketene, Manuel Montero May 1984

Characterization Of Tdi-Hema Homopolymer Prepared Via An Immiscible Solvent System. Synthesis And Investigation Of Oligodichloroketene, Manuel Montero

Theses

The objective of this thesis has been divided in two parts.

The first part is subdivided into two areas. First a "Universal" calibration curve for gel permeation chromatography (GPC) was construc-ted using different molecular weight standards of PMMA and MMA-HEMA co-polymers. By measuring the viscosity of the different molecular weight solutions and calculating the Vr, (retention volume), from GPC data, plots of In [ η ] Mw against Vr and In Mw against Vr are obtained. These curves can be used to obtain the molecular weight of any linear (not crosslinked) copolymer by simple measurements of viscosity and GPC data. …


Microcomputer Controlled Instrumentation System For Studies Of Metabolic Changes In Rats, Murat Dertlioglu May 1984

Microcomputer Controlled Instrumentation System For Studies Of Metabolic Changes In Rats, Murat Dertlioglu

Theses

The system measures the respiratory exchange in rats in a controlled experiment. An interface unit provides data, received from several measurement instruments such as gas analyzers, an electronic flowmeters, electronic thermometer and an electronic hygrometer, to the computer. The data is gathered from different chambers in a multiplexed mode.

The computer samples the chambers sequentially and prints out the results and stores them on the disk. The sampling duration of each chamber and the number of the rats to be tested can be programmed. The system can perform experiments with twelve animals, in the following arrangments, either one group of …


The Involvement Of Labor Unions In Policies Of Worker Safety And Health, Kenneth J. Dzierzawiec May 1984

The Involvement Of Labor Unions In Policies Of Worker Safety And Health, Kenneth J. Dzierzawiec

Theses

American workers are exposed to many seen and unseen hazards in their working environment. As the potential hazards in the workplace became more complicated, so too did the analysis of these hazards, as well as the means of endeavoring to protect a workers safety and health.

In the period between the 1920's and the 1960's the major thrust of Union demands were in the areas of economic gain. Although there was concern for worker welfare.

The period of the late 1960's through the early 1970's brought with it a new outlook on industrial practices as compared with worker welfare and …


Computer Based Instrumentation System For Measurement Of Cardiac Output In Small Animals, Prasad L. Gavaskar May 1984

Computer Based Instrumentation System For Measurement Of Cardiac Output In Small Animals, Prasad L. Gavaskar

Theses

The task of the instrumentation system is to measure cardiac output in animals like rats, dogs, etc. A thermal-dilution method is used for this purpose. The temperature change due to injection of saline is picked up by thermo-couple microprobes implanted in the blood-vessel. The signal after conditioning is fed to a data acquisition system controlled by a computer.

With the help of a computer it is thus possible to monitor and control an experiment on several animals. The computer can sample the chambers sequentially. The sampling cycle duration and frequency are programmable. The data is collected and processed to determine …


Automated Instrumentation System To Monitor Behavioral Experiments, Dilip S. Gokhale May 1984

Automated Instrumentation System To Monitor Behavioral Experiments, Dilip S. Gokhale

Theses

An instrumentation system has been designed to monitor behavioral experiments on monkeys. This instrumentation system is capable of performing these experiments in an automated manner without any human intervention. It is capable of monitoring these experiments concurrently in six boxes. It exhibits several features that make it more versatile than previous instrumentation systems. It is also capable of storing the data generated on to a floppy disk and later transmitting it to the mainframe.

Another feature that makes it more versatile is the flexibility of the system. Presently it is configured to run experiments with variable interval schedules. However with …