Engineering Commons^™

Slow, Red-Green Counterphase (Parvo) And Fast, Black-White Magno) Snow In The Detection Of Scotomata In Primary Open-Angle Glaucoma, Rey Favis

Theses

No one knows why Primary Open Angle Glaucoma sufferers can detect their glaucoma induced blindspots by monocularly fixating on a mark in the center of a screen of television snow. An attempt was made to determine which of two pathways from retina to lateral geniculate nucleus is more involved in the detection of the blindspots. Previous studies demonstrated that the large diameter axon, magno cellular pathway is maximally stimulated by 30 Hertz high contrast black-white patterns. The small diameter axon, parvo cellular pathway is known from past research to be maximally stimulated by 12 Hertz red-green counterphase patterns. It was …

Disinfection Of Wastewater Using Ultraviolet Radiation, David L. Klemm

Theses

The disadvantages associated with the use of chlorine for disinfection, in conjunction with improvements in ultraviolet radiation disinfection technologies have led to the recent increased use of ultraviolet radiation to provide disinfection of effluents from wastewater treatment plants. The theory of ultraviolet radiation and the engineering design of the ultraviolet disinfection system are discussed in depth.

The operational history and records of two wastewater treatment plants that use ultraviolet radiation for disinfection were analyzed in an attempt to develop correlations on the factors that affect ultraviolet radiation disinfection efficiency and to investigate as to whether disinfection with ultraviolet radiation is …

The Study Of Activated Sludge Settleability Using The Solids-Flux Analysis, Churng-Cherng Lin

Theses

The activated sludge was cultivated in two pilot-scale activated sludge systems under three ratios of BOD to N, equal to 20:1, 70:1 and 300:1 in the influent wastewater. The aeration tank of the activated sludge system was constructed in two different configurations: one without compartments in the tank, the other consisting of six compartments. The activated sludge withdrawn from the last compartment of each system was tested in a one-liter graduate cylinder to measure its zone settling velocity. The solids-flux method was employed to analyze the sludge settling characteristic as a function of solids concentration. The results show that the …

Expert System For Preventive Maintenance The Aluminum Extrusion Press And Related Equipment, E-Ping Lin

Theses

ESPM is an Expert System for Preventive Maintenance that provides the framework for application-specific equipment maintenance tools. The expert system for preventive maintenance and diagnosis was developed for the Aluminum Extrusion Press and Related Equipment. The system is built in VP-Expert and is implemented on a personal computer.

The expert system includes many characteristics of an expert system cell because it can be expanded easily by adding new information to its knowledge base or by changing the existing information. The expert system can be connected directly with a PC system through a VP-Expert software package and can interact with C …

Clustering Algorithm For Local Area Network Design In A Cim Environment, A. C. Manjunath

Theses

Communication systems have come to be regarded as being one of the most important aspects in manufacturing enterprises in recent years. It continues to offer enormous potential for improving the efficiency of manufacturing enterprises through Computer Integrated Manufacturing (CIM). It is true however that this potential cannot be realized by developments on the communications front alone. Strategic and economic considerations in installing a communications system in a manufacturing environment is of vital significance.

This thesis, at the outset attempts to bring out some of the issues in the area of communications (research), specifically in relation to CIM. A perception of …

Design Of A Material Handling System For The Automatic Assembly Of A Shower Head, Irshad Meherally

Theses

The design of a Material Handling System for the Shower Head assembly is proposed. The working principle of complete automation and individual workstation is presented using "I-DEAS" software. Alternative equipments and their usage in the automation of the assembly is also proposed. Custom made fixtures, workcarriers, orienters, magazines, part feeders are designed for the assembly. Analysis of design for assembly in terms of cost and efficiency is performed by generating a Coding System Technique.

Modeling And Performance Of Token Bus Lan With Petri Nets, Zhenggang Pan

Theses

A token bus local area network (LAN) is analyzed by Generalized Stochastic Petri Nets (GSPN). The GSPN models of both a single station and LAN for four types of service schemes are obtained and their liveness property is proved. The network performance parameters comprise throughput and delay. The performance analysis for both symmetric and asymmetric single-service systems is conducted for varying load. In order to analyze a token bus LAN with a large number of stations, an approximation method is developed to resolve the .state space explosion problem. A token bus LAN with twenty-one stations is used to show the …

Design For Quality Manufacture : Formulation Of The Macro Architecture For A Dfqm Methodology, Shrad Prasad

Theses

The focus of the available techniques in concurrent engineering for the development and improvement of the design of a product, has been in the areas of product assemblability and manufacturability. These techniques are concerned with the reduction of the cost associated with the manufacture and handling of the product.

The Design For Quality Manufacturability focuses on the quality manufacturability issue of the product design. A macro architecture is developed for the introduction of a new methodology to evaluate designs based on the quality manufacturability of these designs. A set of defects occurring at the assembly stage of the manufacture of …

Optimization Of A 3-Micron Bccd Process For High Density Ccd Registers, Mark Ratner

Theses

In July 1991, Dr. Walter F. Kosonocky proposed a High-Frame-Rate-CCD Imager. The design of the imager is such that the CCD channel width be 3-microns and capable of handling at least 3000 - 5000 electrons per square micron. Using process (SUPREM III) and device (PISCES IIB) simulations, charge handling capacities as a function of implant energy and junction depth were studied. Arsenic implants ranging from 100 to 200keV were driven-in to obtain junction depths between 0.40µm and 0.80µm. As a result of this work it was determined that charge handling capacities as high as 9400 electrons/µm² were achievable with …

Comparing Techniques Of Mapping Pyramid Algorithms Onto The Hypercube : A Case Study For The Connection Machine, Muhammad Ali Siddiqui

Theses

The pyramid structure is most widely used for low-level and intermediate-level image processing and computer vision because of its efficient support of both local and global operations. However, the cost of pyramid computers (PC) may be very high. They also do not support the efficient implementation of the majority of the scientific algorithms. In contrast, the hypercube network has widely been used in the field of parallel processing because it offers a high degree of fault tolerance, a small diameter and rich interconnection structure that permits fast communication at a reasonable cost. Thus, several algorithms have been developed for the …

Ultrasonic Ranging System For Gait Analysis, Mu Wu

Theses

A new method of measuring range for gait analysis is described. The method is based on a coherent measurement of the phase shift of an ultrasonic signal as a function of range.

A prototype of the ranging system was breadboarded, tested, and found to have a relative accuracy of better than 0.5 mm over a range of 3 meters. The maximum range the system is at least 20 meters. The method used here is new and has not been found in the literature. Tt is demonstrated by experiments with a prototype system that can measure distance with a higher accuracy …

A New Method To Optimize The Satellite Broadcasting Schedules Using The Mean Field Annealing Of A Neural Network, Youyi Yu

Theses

This thesis reports a new method for optimizing satellite broadcasting schedules based on the Hopfield neural model in combination with the mean field annealing theory. A clamping technique is used with an associative matrix, thus reducing the dimensions of the solution space. A formula for estimating the critical temperature for the mean field annealing procedure is derived, hence enabling the updating of the mean field theory equations to be more economical. Several factors on the numerical implementation of the mean field equations using a straightforward iteration method that may cause divergence are discussed; methods to avoid this kind of divergence …

Effect Of 2,3-Butanedione Monoxide On Whole-Cell Potassium Channel Currents In Rat Single Myocytes, Youliang Zhou

Theses

The patch clamp technique is a simple procedure which can isolate ion channels on cell membranes. Our previous data have shown that 2,3-Butanedione Monoxime (BDM) could inhibit the calcium current by dephosphorylation of the channel. In this study, the effect of BDM on the potassium channels were investigated with the whole-cell recording method in single myocytes enzymatically isolated from the left ventricle of 3-4 months old rats. Superfusion of myocytes with BDM elicited a dose dependent decrease of the outward transient potassium current. BDM with concentrations of 5, 20 and 50 mM reduced the maximal peak potassium current by 7.3 …

Kinetic Measuremenmt Of Decomposition Of Aniline, 2,4-Dichlorophenol And 1,2,4-Trichlorophenol Using A Calorimetric Method, Ming-Chin Chang

Theses

Biological treatment techniques for detoxification of toxic organic compounds have been studied and applied for many years. There are many research and commercial applications proving that the biological method is more economic and efficient than the other treatment methods.

The traditional biomass measurements are time-consuming tasks. Researchers have intended to develop a simpler, faster, and also accurate method for determining the bioactivity. This study has tried to use the microcalorimetric method to monitor the energy productions from the degradation of aniline, 2,4-Dichlorophenol and 1,2,4-Trichlorobenzene. Thereafter, by utilizing the data obtained from the present study, it was possible to compute kinetic …

Pure Strong Competition For Two Microbial Populations In A Chemostat, Efthimios Ioannis Banias

Theses

The dynamics of pure, strong, double competition between two microbial populations in an ideal chemostat have been investigated by using mathematical and numerical analysis. The two nutrients competed for have been assumed to be complementary for both competitors. Inter active models have been used for the specific growth rates. Two cases have been considered; one in which neither of the two substrates exerts inhibitory effects on the growth of either one of the competing populations, and one in which the growth of one population is inhibited by only one of the two substrates. The primary focus of this investigation was …

Evaluating The Homogeneity Of Solidification/Stabilization Treated Waste Soils By Chemical Analysis Method, Mei Liu

Theses

Solidification/Stabilization technology has been widely used for waste treatment, especially for heavy metals, non-volatile wastes, radioactive wastes and soils. Homogeneity is a very important criterion for this kind of technology.

This study focuses on the development of a method to evaluate the homogeneity of S/S treated soil. A chemical analysis method, atomic absorbance, is employed to evaluate the distribution of S/S reagent in a soil-cement mixture and thus the uniformity of the soil-cement mixture. Also, a fluorescent tracer method is discussed in this study, which can be used to estimate the homogeneity of the soil-cement surface. The fluorescent tracer method …

Inability Of Phanerochaete Chrysosporium To Degrade Polychlorinated Biphenyls In Sand, Pankaj Pankaj

Theses

The white rot fungus Phanerochaete chrysosporium has been previously found to successfully degrade a wide spectrum of chlorinated aromatic hydrocarbons (some of them in soil or sand matrices). In this research, it was tested if the fungus could also degrade a very recalcitrant class of pollutant, i.e. Polychlorinated Biphenyls (PCBs) in sand at a concentration of 100 ppm (w/w PCB to sand). For this purpose, a number of experiments were performed, in which several operating parameters, such as nutrient concentrations (nitrogen and glucose), amount of initial biomass, aeration, and degree of chlorination of the PCBs were varied. The results obtained …

Wear And Friction Of Titanium Nitride On Ultra High Molecular Weight Polyethylene Under Oscillating Motion For Evaluation Of Use In Articulating Orthopedic Applications, David Scott Jacobson

Theses

Materials are a factor in the performance of articulating orthopedic implants. An oscillating tribometer is utilized to investigate mechanisms of wear and friction of TiN (titanium nitride) coated on Ti-6Al-4V (titanium) alloy against UHMWPe (ultra high molecular weight polyethylene). Three thicknesses of TiN coating (1.76 pm, 4.15 µm, and 10.5 µm) are used to evaluate the performance of each in UHMWPe wear reduction and coating integrity. An uncoated Co-Cr (cobalt chromium) coupon is used against UHMWPe pins for control purposes. Oscillations are carried out to 10 million cycles to discover and evaluate short- and long-term wear mechanisms. Mass differentials and …

Evaluation Of Homogeneity For Hazardous Waste Solidification By Video Imaging Technique, Yi-Min Gao

Theses

The field of chemical solidification has just begun to mature into an accepted environmental technology for hazardous waste disposal. From the engineering point of view, some key issues still dominate the feasibility and effectiveness of hazardous waste solidification process. "Mixing" is essentially regarded as the most critical element but unfortunately, no evidence has been proposed to prove the homogeneity of the large monolith produced by solidification in order that the effectiveness of the solidification process can be evaluated in satisfactorily short time. The Homogeneity Evaluation by Video Imaging System (HEVIS) proposed in this study is to solve this problem with …

Low Temperature Synthesis And Characterization Of Lpcvd Silicon Dioxide Films Using Diethylsilane, Chakravarthy Srinivasa Gorthy

Theses

Diethylsilane (DES) has been used as a precursor to produce silicon dioxide films by low pressure chemical vapor deposition. These films were synthesized in the temperature range of 350 to 475°C thus allowing the use of the material as an intermetal dielectric or as a top layer passivation coating in microelectronic devices. In that process, the growth rate was observed to follow an Arrhenius behavior yielding an activation energy of 10 kcal/mol. The growth rate was also observed to increase with higher pressure and to vary as a function of the square root of the DES flow rate and O …

Processor Allocation Strategies For Modified Hypercubes, Nagasimha G. Haravu

Theses

Parallel processing has been widely accepted to be the future in high speed computing. Among the various parallel architectures proposed/implemented, the hypercube has shown a lot of promise because of its poweful properties, like regular topology, fault tolerance, low diameter, simple routing, and ability to efficiently emulate other architectures. The major drawback of the hypercube network is that it can not be expanded in practice because the number of communication ports for each processor grows as the logarithm of the total number of processors in the system. Therefore, once a hypercube supercomputer of a certain dimensionality has been built, any …

The Effects Of Twist On Pressure Through A Teflon Vascular Prosthesis, Steven Alfred Olivieri

Theses

A closed loop fluid system was developed which mimics the flow curve in the human circulatory system in order to test the effects of pressure drop and flow velocity on artificial arterial implants. This device consists of a piston pump connected to a microcomputer controlled servo-motor. Fluid (in this case distilled water) flows through transparent Tygon tubing to a test chamber. The prosthetic tube is placed in the fluid but is attached through a specially constructed chamber. The pressure across the implant can be measured for different conditions. System compliance was generated by using flexible tubing in the return loop …

An Embedded Controller-Based Fiber Optic Sensor For Use In Fresh Concrete, Zhaowu Zhang

Theses

The principle of refraction and reflection of light in optical fibers is applied to detection of air bubbles in a previous thesis. In the earlier work, a microcomputer was employed in acquisition and processing of air bubble data. In the present thesis, an embedded controller system is interfaced and programmed in order to replace the microcomputer. In this way, the system can be more easily integrated into field construction operations. Reflected light intensity signals are detected and analyzed by a microcontroller. The entrained percentage of air in concrete is displayed immediately. The signal can be transferred through a UART (Universal …

Local Stress Due To A Radial Loading At Nozzle-Pipe Connection With Different Thickness, Guosheng Lu

Theses

This thesis presents an analysis using the finite element method of the local stress at the nozzle and pipe connection subjected to a radial loading.

In this study, the local stress factor (for membrane and bending stresses) is presented in a series of plots with beta (nozzle radius/pipe radius) values ranging from 0.1 to 1.0 and gamma (pipe radius/wall thickness) values ranging from 10 to 100. The membrane and bending stresses in longitudinal and circumferential directions of the run pipe are computed as a function of the dimensionless parameters, beta and gamma.

For a given external radial loading with different …

Applications Of Digital Signal Processing With Cardiac Pacemakers, Merry Thi Tran

Dissertations and Theses

Because the voltage amplitude of a heart beat is small compared to the amplitude of exponential noise, pacemakers have difficulty registering the responding heart beat immediately after a pacing pulse. This thesis investigates use of digital filters, an inverse filter and a lowpass filter, to eliminate the effects of exponential noise following a pace pulse. The goal was to create a filter which makes recognition of a haversine wave less dependent on natural subsidence of exponential noise.

Research included the design of heart system, pacemaker, pulse generation, and sensor system simulations. The simulation model includes the following components:

• Signal source, …

A New Approach To The Decomposition Of Incompletely Specified Functions Based On Graph Coloring And Local Transformation And Its Application To Fpga Mapping, Wei Wan

Dissertations and Theses

The thesis presents a new approach to the decomposition of incompletely specified functions and its application to FPGA (Field Programmable Gate Array) mapping. Five methods: Variable Partitioning, Graph Coloring, Bond Set Encoding, CLB Reusing and Local Transformation are developed in order to efficiently perform decomposition and FPGA (Lookup-Table based FPGA) mapping. 1) Variable Partitioning is a high quality hemistic method used to find the "best" partitions, avoiding the very time consuming testing of all possible decomposition charts, which is impractical when there are many input variables in the input function. 2) Graph Coloring is another high quality heuristic\ used to …

Modeling Techniques For Water Supply Forecasting In The Western United States, David Charles Garen

Dissertations and Theses

Water supply forecasting in the western United States is the prediction of the volume of water passing a given point on a stream during the primary snowmelt runoff season. Most water supply forecasts are produced from multiple linear regression models using snowpack, precipitation, and streamflow measurements as independent variables. In recent years, conceptual watershed simulation models, typically using a time step of one day, have also been used to produce these forecasts.

This study examines model usage for: water supply forecasting in the West and has three specific purposes. The first is to examine the traditional usage of multiple linear …

An Improved Formulation Of The Temperature Dependence Of The Gummel-Poon Bipolar Transistor Model Equations, Chorng-Lii Liou

Dissertations and Theses

A number of shortcomings were found after complete derivation of the temperature dependence of equations, and the expressions related to the Early effect in the present Gummel-Poon 2 model, as implemented in the TEKSPICE program. The formulation and application of improved model equations is presented, followed by a detailed comparison of the existing model with the one developed in this work.

Effectiveness Of Additive Correction Multigrid In Numerical Heat Transfer Analysis When Implemented On An Intel Ipsc2, James D. Padgett

Dissertations and Theses

The effectiveness of the Additive Correction Multigrid (ACM) algorithm, a line-byline Tri-diagonal Matrix Algorithm (TDMA), and simple Gauss-Seidel (GS) iteration in numerical heat transfer analysis is investigated on a conventional single processor computer and on a distributed memory parallel computer. The performance of these methods is studied by solving a two-dimensional, steady heat conduction problem. The execution time of ACM on a single processor is proportional to the number of unknowns to the 1.5 power. This is in contrast to the execution time of the TDMA for which the execution time is proportional to the number of unknowns to the …

Digital Model Of A Generic Infrared Tracker, James Michael Brown

Graduate Theses - Electrical and Computer Engineering

Personal computer based simulations are popular because of the wide availability of personal computers. In this thesis, a simple simulation model of a generic infrared tracker is developed for the personal computer. This thesis first centers on the definition of a generic infrared tracker and the development of a tracker model. The remainder of this thesis is a description of the personal computer based computer simulation model, and a discussion of results of simulation runs to characterize the tracker model response. The conclusion of this thesis is that the simple simulation model serves both as a prototype for developing a …