Engineering Commons^™

Computational Aspects Of A Three Dimensional Non-Intrusive Particle Motion Tracking System, Avadhani S. Ashok

Theses

Development of a technique for non-intrusive particle motion tracking in three dimensions is considered. This technique is based on the principle of magnetic induction. In particular, the determination of the position and onentation of the particle from the information gathered is the pnncipal focus of this thesis. The development of such a system is motivated by the need to understand the flow patterns of granular material. This is of cntical importance in dealing with problems associated with bulk solids flows which occur in almost all industries and in natural geological events. A study of the current diagnostic techniques reveals the …

Analysis Of Electric Field On Surface Of An Atomically Sharp Field Emitter, Ziyan Cheng

Theses

In this thesis, exact calculation and computer simulation of an atomically sharp emitter are presented. In the theoretical analysis, the cathode-anode or cathode-gate complex is modeled for cone- and wedge-shaped emitters so that exact solution can be obtained. The exact solution reveals that the field on the emitter surface depends not only on the sharpness of the emitter, but also on the global geometry of the field emitter, gate, and anode complex. This finding is contrary to a widely accepted concept that field is predominantly determined only by local curvature of the tip.

The theoretical results are confirmed by computer …

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 …

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 …

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 …

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 …

A Computer Implementation Of A Multi-Neuron Expandable Network, Mary Ellen Ellen Aleksza

Theses

The primary goal of this thesis is to develop a small, expandable neural network that oscillates when presented with an appropriate stimulus. This model will be used in the future as a base to create larger networks. Future studies of these larger networks may be used in the simulation of neuronal activity such biological oscillators.

This thesis encompasses a study of neuron activity, neural networks, neuron models and biological oscillators. The focus of the thesis is the modification and expansion of a single neuron simulation into a simulation of an interconnected multi-neuron oscillatory network.

A single neuron model based on …

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 …

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 …

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.

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 …

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 …

Improvement Of Light Collection Efficiency By Laser-Induced Patterning The Surface Of Schottky-Barrier Solar Cells, Kejia Fang

Theses

In order to achieve maximum light collection efficiency in silicon made solar cells, reflectivity of the silicon surface must be reduced to as low level as possible. In the past, researchers have concentrated on coating the Si surfaces with anti-reflection coatings. Another approach was to form textures on the Si wafers to capture further the light impinging on the solar cells.

Theoretical studies, which were based on ray tracing approach, revealed that some geometrical patterns are better capturing the light than others. In this work, different geometrical surface configurations on a Cu/n-Si Schottky-barrier solar cell have been investigated. The configurations …

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 …

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 …

Improving The Throughput Of Plasticating Extruders : Manufacture Of Non-Circular Pellets, Measurement Of Their Interparticulate Friction Coefficient, And Implications For Screw Design, Chia-Ying Liu

Dissertations

This dissertation addresses the hypothesis that the interparticulate friction coefficient of a bed of polymeric particulates is a function of the cross-section of the pellets. Most pellets have a circular cross-section especially those that are strand cut. But when such pellets constitute a particulate bed there are few restrictions to adjacent pellets turning with respect to each other, or of the beds rupturing under shear load. This rupture can occur in plasticating extrusion, and it results in a poorly mixed melt with an inhomogeneous temperature distribution. The temperature fluctuations cause viscosity fluctuations which in turn cause pressure fluctuations. The pressure …

Series Compensation Investigation On The Hydro-Quebec And Nypa 765 Kv Transmission System : Modeling And Stability Analysis, Hans J. Candia

Theses

This thesis presents a mathematical approach for raising the power steady state stability limit by adding series capacitive compensation to a transmission line. The effect of series capacitive compensation and degree of compensation were investigated in detail. The power system studied includes an automatically controlled power system, IEEE Type I.

The results of the actual and theoretical steady state stability limits for a given series capacitance location and degree of compensation were obtained by applying the frequency domain technique. The natural frequencies of each compensated power network were examined.

The best location for series capacitive compensation is proposed which is …

Mathematic Models On Leaching Behavior Of Chemical Solidification And Stabilization Process For Heavy Metal Sludges, Sz-Hung Chen

Theses

Chemical Solidification and Stabilization of toxic metal-containing sludges is one of the most important problems for environmental protection. Although Chemical Solidification and Stabilization of hazardous wastes prior to disposal is increasing in importance, very little work has been done concerning the leaching mechanisms and kinetic models.

In this study, we apply Freundlich & Langmuir isotherms on Chemical Solidification and Stabilization process, and the theoretical results match with experimental data very well. In the same time, we develop a simple methematical kinetic model which relates leaching concentration of heavy metal to curing time. In this study kinetic model, what you need …

Ion Exchanged Glass Waveguides With Efficient Coupling To Fibers And Lasers, Shiqing Hu

Theses

To be of practical use in optical communications networks, optical components must have both low on-chip losses and efficient coupling to fibers, semiconductor lasers and detectors. In this thesis work two types of channel waveguides were designed and fabricated on BK7 glass substrate using a low-cost ion-exchange process. The first type of waveguide was formed in a simple sequence of ion-exchange and post-exchange annealing. These single mode waveguides had large mode size and were efficiently coupled to single mode fibers. The lowest loss achieved in fiber-guide direct coupling was 1.25 dB. The second type of waveguide was formed in a …

A Finite Element Thermal And Diffusion Analysis At Bearing Metal Interface In Extrusion Processes, Biju Dennis

Theses

A mathematical model is developed to study the effect of extrusion speed and the bearing length on the surface temperature along the die billet interface. The surface temperature distribution resulting from the plastic work done on the die billet interface is studied. Finite element analysis is done on the model incorporating the mass transport effect occurring during the extrusion process and the interdependence of various parameters are presented. Die wearing problem is analyzed considering the effect of diffusion. Thermal analogy of the diffusion problem is utilized in the development of the mathematical model for diffusion problem and finite element analysis …

Computer Aided Shape Optimization Using Finite Element Analysis, Charanpreet Singh Bagga

Theses

Various theories behind Computer Aided Shape Optimization are studied. A special attention is paid to the shape representation, mesh generation and refinement during the shape optimization process. Shape optimization process for a wall bracket is performed using the Computer Aided Engineering package of I-DEAS. Finite element analysis of the wall bracket is done and the stress distribution over the bracket is studied. The bracket is trimmed in the selected low stress regions using shape optimization capability of I-DEAS and an optimized shape of the wall bracket is obtained. The end product is evaluated using Supertab module of I-DEAS as well …

Computer Numerical Controlled (Cnc) Machining Of Screws And Dies For Plasticating Extruders : Determination Of The Criteria For Implementing Cnc Machining, Nilesh H. Desai

Theses

The work of this thesis is dedicated to the manufacturing industry making production equipment to manufacture plastic products. The main theme of the thesis is to determine the criteria for implementing Computer Numerical Control machining to make parts with complex geometries for production equipment.

A small manufacturing company with job shop type of production was chosen as the subject and study of extruder manufacturing process was performed. The various available alternatives of CNC manufacturing units available in the market were chosen and their feasibility examined.

At present a large variety of CNC machine tools are available in the market, offered …

Conditional Artificial Dielectric : Optically Controlled Microwave Modulator, J. Manuel Jimenez

Theses

A conditional artificial dielectric with embeddings of either CdS, GaAs or Si in PMMA form the dielectric material of a microstrip in a homodyne microwave detection system. The system consists of a Michelson or Mach-Zehnder interferometers with the microstrip placed in one arm. The index of refraction of the microstrip substrate is modulated by chopped incident light causing amplitude and phase variations in the incoming RF signal. Those variations are detected by mixing the light modulated microwave carrier(information channel) with the unmodulated carrier (reference channel) in the interferometer. The output is sensed by the square law detector and a lock-in …