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Multistage Interconnection Networks : Improved Routing Algorithms And Fault Tolerance, Kuo-Yu Chen May 1991

Multistage Interconnection Networks : Improved Routing Algorithms And Fault Tolerance, Kuo-Yu Chen

Theses

Multistage interconnection networks for use by multiprocessor systems are optimal in terms of the number of switching element, but the routing algorithms used to set up these networks are suboptimal in terms of time. The network set-up time and reliability are the major factors to affect the performance of multistage interconnection networks. This work improves routing on Benes and Clos networks as well as the fault tolerant capability. The permutation representation is examined as well as the Clos and Benes networks. A modified edge coloring algorithm is applied to the regular bipartite multigraph which represents a Clos network. The looping …


Dynamic Analysis Of The Generalized Slider Crank, Sahidur Rahman May 1991

Dynamic Analysis Of The Generalized Slider Crank, Sahidur Rahman

Theses

A numerical technique is used to analyze the kinematics of the generalized slider crank mechanism and an analytical technique to derive dynamic force equations for that mechanism has been formulated. The numerical technique used for displacement analysis is based on a combination of Newton-Raphson and Davidon-Fletcher-Powell optimization algorithm using dual-number coordinate-transformation matrices. Velocity analysis is performed by using a dual number method. Finally, dynamic force analysis is accomplished on the basis of the dual-Euler equation and D'Alembert's principle. The approach is developed in such a manner that a digital computer can detect when a solution is possible and then solve …


Off-Line Programming Using Igrip, Narahari K. Bhandary May 1991

Off-Line Programming Using Igrip, Narahari K. Bhandary

Theses

AT&T's FWS-200 (Flexible Work Station) has been modeled and simulated to implement Off-Line Programming (OLP). IGRIP (Interactive Graphics Robot Instruction Program) from Deneb Robotics, Inc. has been used to simulate the FWS operation.

A GSL(Graphics Simulation Language) program has been used to simulate the chip placements during PCB assembly. The program leads the user through the motions of chip placement, and after the simulation run downloads the motion sequence to the FWS. The animation sequences of the FWS have been downloaded to the FWS on the Factory Floor using a C program, which is utilized to communicate the data to …


Performance Evaluation And Comparison Of Ordinary, Adaptive And Exhaustive Services In The Token Ring Network, Hong Wang May 1991

Performance Evaluation And Comparison Of Ordinary, Adaptive And Exhaustive Services In The Token Ring Network, Hong Wang

Theses

Ordinary service and exhaustive service are two major alternatives of scheduling policies considered in providing access to token ring networks. Results to date have shown that exhaustive service results in more delay to lightly loaded stations in asymmetric traffic while ordinary service wastes time in circulating the token after each transmission. This work presents a new token passing protocol, called adaptive service, in which the token holding time is dynamically changing; in this way, it provides a fair compromise between exhaustive and ordinary service. The simulation results show that in asymmetric traffic, adaptive service gives improvement on the local delay …


Performance Evaluation In Terms Of Congestion And Flow Control Of Interconnected Token Ring Local Area Networks, Muhammad Salim Raza May 1991

Performance Evaluation In Terms Of Congestion And Flow Control Of Interconnected Token Ring Local Area Networks, Muhammad Salim Raza

Theses

In an interconnected network, if user demands are allowed to exceed the system capacity, unpleasant congestion effects occur which rapidly neutralize the delay and efficiency advantages. Congestion can be eliminated by using an appropriate set of traffic monitoring and control procedures called flow control procedures. This thesis first investigates the major technical concepts underlying the token-ring technology; performance and flow control issues and then gives an approximate analytical solution in terms of mean end-toned delay in a system of token-ring local area network interconnected through bridges. The analytical solution is based on an approximation of the mean end-to-end delay in …


Image Enhancement And Analysis Of Leukocyte Adhesion, Yee-Ruh Lin May 1991

Image Enhancement And Analysis Of Leukocyte Adhesion, Yee-Ruh Lin

Theses

The image of leukocyte adhesion to microvascular walls in the isolated rat perfused heart model has been observed and processed. Some of the fluorescent labeled leukocytes are barely visible due to microscope focal plane and the motion of objects. The purpose of this thesis is to extract leukocyte from the image of the experimental data using image enhancement and analysis (segmentation) techniques and develop a program to handle automatically counting of leukocytes in a predefined scene.


Effect Of Shrinkage On The Design And Manufacture Of Plastic Parts In Injection Molding Using Cad/Cam Techniques, Deepak M. Shastri May 1991

Effect Of Shrinkage On The Design And Manufacture Of Plastic Parts In Injection Molding Using Cad/Cam Techniques, Deepak M. Shastri

Theses

Computer aided design software in injection molding has revolutionized injection molding in the design and manufacturing processes. Computer Aided Engineering can be applied to injection molding to increase the process efficiency, reduce part costs, and produce accurate parts in less time. The mold designer has many software programs to choose from to produce satisfactory mold designs from part geometries, and a correct selection can produce profitable results. A study of the need for and the scope of computers in injection molding is performed to evaluate the suitability of a CAE package by considering the value added to the parts using …


Biological Coal Desulfurization, Ming Le May 1991

Biological Coal Desulfurization, Ming Le

Theses

Sulfur removal from coal before combustion is of considerable interest to avoid emission of oxides of sulfur(SOx). Chemical and physical methods have been developed for removing the inorganic sulfur component in coal. This component is generally associated with pyrites(FeS2). However, no commerical methods have been developed for the removal of the organic sulfur conponent. This study describes microbial methods for removing organically bound sulfur from coal. The specific goals of this study were to ascertain whether a robust biologically active population such as activated sludge biomass can remove organic sulfur from coal and to devise sulfur analytical methods …


Burn Wound Healing Evaluation By Infrared Imaging, Shang-Yuan Chen May 1991

Burn Wound Healing Evaluation By Infrared Imaging, Shang-Yuan Chen

Theses

Infrared imaging is a pictorial method of temperature representation. Its advantage in the treatment of burns is that it is a non-invasive, safe and reliable method for estimating the area, temperature and depth of burns. An Imaging Burn program was developed for comparing changes in burn area in response to treatment with time. The program proved itself capable of determining the surface area of simulated lesions on the skin of human volunteers to within an error of 1.6 percent. The size and temperature of burn lesions in patients was recorded. First degree burns were warmer than surrounding areas of normal …


Design For Manufacturability : Re-Design Of Pencil Sharpener For The Ease Of Assembly, Amit R. Rathod May 1991

Design For Manufacturability : Re-Design Of Pencil Sharpener For The Ease Of Assembly, Amit R. Rathod

Theses

A Design For Manufacturability (DFM) approach is used to analyze the existing design of a pencil sharpener, and to reduce and re-design the parts of pencil sharpener for the ease of assembly. The procedure for the selection of a suitable and economical assembly method is based on the Boothroyd and Dewhurst methods. Analysis of the initial design for manual assembly and re-design for automatic as well as manual assembly is presented. An algorithmic approach for simplified generation of all mechanical assembly sequences and selection of the assembly sequences is presented using De Fazio and Whitney approach.


Experiments In Aerobic And Anaerobic Biodegradation Of Methylene Chloride Using Activated Sludge, Vivek Chandrakant Sinkar May 1991

Experiments In Aerobic And Anaerobic Biodegradation Of Methylene Chloride Using Activated Sludge, Vivek Chandrakant Sinkar

Theses

Biological removal of methylene chloride was studied under aerobic and anaerobic conditions using activated sludge cultures. Shaker flask experiments were conducted to test the ability of the microorganisms to degrade methylene chloride under aerobic conditions. Hydrogen peroxide was used a as source of dissolved oxygen to minimize physical removal of methylene chloride due to aeration. The effect of secondary substrates like glucose, cellulose acetate, ammonium acetate and nutrient broth on biodegradation of methylene chloride was studied. Biodegradation in the presence of surfactant and alkaline stress was also investigated.

No significant degradation was observed in all aerobic experiments.

Anaerobic sludge was …


Acid Recovery Of Cadmium And Lead From Immobilized Activated Sludge Used To Biosorb Metals, Chandrakanth Hartman May 1991

Acid Recovery Of Cadmium And Lead From Immobilized Activated Sludge Used To Biosorb Metals, Chandrakanth Hartman

Theses

A study of the adsorption and subsequent desorption of heavy metals using various concentrations of hydrochloric acids has been performed.

To accomplish this task, the following areas were investigated : immobilization of the sludge, adsorption of heavy metals, various concentrations of acid used as stripping agents, examination of the relative fractions of heavy metals obtained using various stripping agents, and the actual concentration of the acid at a particular fraction.

It was observed that water helps in extraction of cadmium to a certain extent, but lead cannot be extracted with water. Also, water mixed with dilute hydrochloric acid is more …


Biodegradation Of Styrene In A Recirculation Reactor Using Immobilized Activated Sludge, Shreyans Dilip Shah May 1991

Biodegradation Of Styrene In A Recirculation Reactor Using Immobilized Activated Sludge, Shreyans Dilip Shah

Theses

The performance of immobilized cells in the biological treatment of hazardous waste was investigated using a recirculating flow reactor in batch mode. A mixed culture activated sludge from a municipal waste water treatment plant was immobilized in calcium alginate gel, The bio-oxidation ability of these microbes towards a model toxin (styrene) was studied under closed system using dilute H2O2 solution as an oxygen source.
The process parameters studied were as follows:

  1. Effect of flow rate of recycle stream,
  2. Effect of biomass loading,
  3. Effect of spiking concentration of styrene, and
  4. Flow pattern and average residence time within the …


Catalytic Oxidation Of Trace Concentrations Of Chlorinated Hydrocarbons Over 1.5% Platinum On Alumina/Monolith, Yi Wang May 1991

Catalytic Oxidation Of Trace Concentrations Of Chlorinated Hydrocarbons Over 1.5% Platinum On Alumina/Monolith, Yi Wang

Theses

The catalytic oxidation of chlorinated hydrocarbons CH2Cl2 (DCM) and C2HCl3 (TCE) was investigated over a 1.5% Pt on Al2O3/monolith at 150 to 450°C. The studies were conducted at space velocities from 1,000 v/v/hr to 30,000 v/v/hr. Chemical equilibrium calculations showed the potential conversion and products distribution. The reactivity and selectivity for destruction of these compounds with air over Pt catalyst were evaluated experimentally. This research was conducted in a tubular reactor system with associated feed and product flow measuring equipment. Feed and product streams were analyzed using gas chromatography (GC) with ECD, FID and …


Analysis Of The Influence Of Natural Wear And Tear In Gates And Runners On The Filling Of A Balanced Multi-Cavity Injection Mold, Ranga Reddy V. Adavelly May 1991

Analysis Of The Influence Of Natural Wear And Tear In Gates And Runners On The Filling Of A Balanced Multi-Cavity Injection Mold, Ranga Reddy V. Adavelly

Theses

Design of injection molds is outmost important in the manufacture of parts. Its components runners and gates significantly influence the mold filling. Using a simulation package for injection molding a balanced multi-cavity mold was designed. Wear in the gates of runner was simulated by varying the cross-sectional area of the components. Influence of wear of tear in gates of runners on mold filling was measured in terms of flow rate of time of fill. Detailed analysis is done on four different models using four different materials Polycarbonate, Polypropylene, Nylon6 and Polybutylene terephthalate. Graphical display of result is presented and analyzed …


3-D Structure Recovery Using Unified Optical Flow Field Approach, Anees Ahmad May 1991

3-D Structure Recovery Using Unified Optical Flow Field Approach, Anees Ahmad

Theses

Recovery of the 3-D structure that is characterized by an Nth order factorable and/or non-factorable polynomial equation is studied in this thesis. Analytical tools have been employed to analyze and solve the problem. The solution is based on the direct method, which is derived from the unified optical flow field, which, in turn, is an extension of optical flow to spatial image sequences. Least squares formulation has been employed for optimum estimation. The method used does not require the establishment of point to point correspondence, nor the estimation of the optical flow, as an intermediate step.

The theoretical results …


The Design And Testing Of A Personal Computer Controlled Scanning Acoustic Microscope For Orthopaedic Surgical Applications, Hubert Heinrich Berndt May 1991

The Design And Testing Of A Personal Computer Controlled Scanning Acoustic Microscope For Orthopaedic Surgical Applications, Hubert Heinrich Berndt

Theses

This thesis describes scanning acoustic microscopy and ultrasonic image processing to characterize and evaluate materials of known properties, as well as novel materials. This work describes the assembly and testing of a PC based device for nondestructive evaluation of bone materials for usage in orthopaedics research. It includes the identification of some hardware problems and their solution, and it also describes different image processing techniques that have been developed and applied in this work. In a growing number of disciplines it has been discovered that an acoustic microscope can provide new information, especially about the elastic properties of specimens and …


Electroretinogram Modeling : Parameter Identification And Intensity-Response Function Fits, Juan J. Castro May 1991

Electroretinogram Modeling : Parameter Identification And Intensity-Response Function Fits, Juan J. Castro

Theses

Electroretinography testing provides many useful techniques for clinical diagnosis of the visual system. However, the interpretation of the electroretinogram data involves a great amount of subjectivity. The use of mathematical models and parameter estimation techniques to fit the electroretinogram data supply a non-subjective and more standard way for analysis of the electroretinogram data. Mathematical models provide a way of summarizing the information enclosed in the raw electroretinogram response into a small set of parameters that define the response.

This thesis presents a mathematical model for the electroretinogram response due to light stimuli. It also provides a non-subjective method for obtaining …


The Performance Of Training Pattern Sets In A New Art-Based Neural Architecture For Image Enhancement, Fu-Chun Chang May 1991

The Performance Of Training Pattern Sets In A New Art-Based Neural Architecture For Image Enhancement, Fu-Chun Chang

Theses

Neural network can be applied on the image enhancement after adding another two layers into the Adaptive Resonance Theory architectures (ART 1). The analysis for selecting a nice training pattern set associate the appropriate vigilance values is the main concerns in this thesis. For a single training pattern ,the network can act as a mathematical morphology operators such as erosion , dilation, opening and closing. With more than one training patterns in the network, 16 experiments are tested and are compared to each other in order to find the best selection for doing the image enhancement work. With both the …


The Bandwidth Allocation Of Atm Control By Neural Networks, Jin-Syan Chou May 1991

The Bandwidth Allocation Of Atm Control By Neural Networks, Jin-Syan Chou

Theses

In this thesis, we develop a neural network method based on Adaptive Resonance Theory to train and control the optimum bandwidth allocation of ATM network. In Broadband Integrated Service Digital Network (BISDN), the Asynchronous Transfer Mode (ATM) is already adopted as the transfer facility by CCITT. ATM is a high-bandwidth, low- delay, fast-packet switching and multiplexing technique. Using ATM technique, we can flexibly rearrange the network and reassign the bandwidth to meet the requirement of all types of services. As an effective optimization method, Genetic Algorithm (GA) is applied to implement the bandwidth allocation of ATM. Then, we use Adaptive …


A Process For Implementing Cim In A Small Manufacturing Facility, Tushar R. Desai May 1991

A Process For Implementing Cim In A Small Manufacturing Facility, Tushar R. Desai

Theses

This work is dedicated to small manufacturing enterprises seeking to explore Computer Integrated Manufacturing (CIM) technology, which is the recent trend in the manufacturing world. The main theme of this thesis is to improve productivity, product quality and reliability, and to reduce costs by integrating various discipline in small manufacturing environment, using computer technology.

To achieve this goal, a hypothetical small manufacturing company was chosen as a subject. The typical functional and organizational structures were analyzed and possible problem areas were highlighted. The problems relating to manufacturing process were studied in detail, and possible solutions were proposed to computerize the …


A Modified M/G/1/N System And Its Application, Bernice Annette Figueroa May 1991

A Modified M/G/1/N System And Its Application, Bernice Annette Figueroa

Theses

We study a single server queueing system with finite buffer, Poisson arrivals and exceptional service requirements for the first customer in each busy period. The system is studied as a Markov Chain and the limiting probability distributions are obtained. The explicit form sorution for the queue length distribution, blocking probability, waiting time distribution as well as the busy period are derived through the Laplace-Stieltjes transform method. These results are then applied to a tandem system with a finite buffer in front of the first station and no intermediate buffer between the two stations. Finally, similar results are obtained for the …


Rule-Based Module And Object-Oriented Design For Optical Character Recognition, Min Gao May 1991

Rule-Based Module And Object-Oriented Design For Optical Character Recognition, Min Gao

Theses

In this thesis, I present a optical character recognition technique based on the rule-based module and object-oriented design. A document image is first scanned, and then segmented into isolated characters by the use of projection profiles. The recognition procedures include three steps: contour extraction, strokes detection and rule-based classification. The contour extraction is to extract the outbound boundary and to perform the boundary linking and noise removal. The stroke detection is to detect the features or strokes of the outbound boundary, such as horizontal/vertical lines, left/right slash lines and left-/right-opened curves. The rule-based classification consists of two rules: character definition …


Load-Deformation Behavior Of Reinforced Fibrous Concrete Beams, Rujun He May 1991

Load-Deformation Behavior Of Reinforced Fibrous Concrete Beams, Rujun He

Theses

This study deals with the load-deformation behavior of steel fiber reinforced concrete beams.

Theoretical development of moment-curvature and load-deformation relationships is presented in this paper. It is based on the assumption that the failure at a section occurs either when the force equilibrium equation is violated or when the concrete elements start to get crushed in the member. The complete stress-strain relationship of plain fibrous concrete in reference [2] was used in this study.

A special computer program is presented herein to carry out the theoretical studies of load-deformation behavior of simply supported beam under two-point loading. The validity of …


Representing Tolerances In A Geometric Modeller, Chih-Tsung Huang May 1991

Representing Tolerances In A Geometric Modeller, Chih-Tsung Huang

Theses

Current geometric modeller contains dimension information only. This thesis describes how tolerance can be added to a geometric modeller. The modeller is based on a hybrid design of the Constructive Solid Geometry (CSG) scheme and Boundary Representation (B-Rep). Various tolerances based on the ANSI standard are considered.


Computer Graphic Simulation Of Sweeping Of Solid Objects, Jr-Jyun Jang May 1991

Computer Graphic Simulation Of Sweeping Of Solid Objects, Jr-Jyun Jang

Theses

This thesis is on the computer graphic simulation of the swept volume of a solid object undergoing Euclidean motions (including translation and rotation). The study helps visualize different types of Euclidean motions and supports the previously developed swept volume theories by providing graphic realism.Included in the thesis presentation are the following :

  1. Description of Euclidean motions of polyhedral objects, using ruled surfaces to represent swept volumes.
  2. Representation of sweeping of solid objects, -using parametric cubic equation and sweep differential equation.
  3. Simulation of motions of PUMA and IBM robots.
  4. Wire-frame and shaded image displays of swept volumes.


Brushless Dc Motor Speed Control System With Saturation Nonlinearity, Khawja M. Kamal May 1991

Brushless Dc Motor Speed Control System With Saturation Nonlinearity, Khawja M. Kamal

Theses

A study of a three-phase, pulse-width modulated, velocity controlled brushless DC motor speed control system is presented. Previous works on brushless DC drive systems could not explain global instability, due to linear approximations. A complete three-phase system model is presented here, along with a simplified single-phase model, which is similar to a conventional DC motor model. The models incorporate saturation nonlinearity. The brushless DC drive system is analyzed and simulated. Special emphasis is laid on the study of the limit-cycle phenomenon, due to saturation nonlinearity. Global instability is accounted for and relevant parameter regions are established for global stability. The …


Numerical Simulation Of The Heating Of Glass Mat Thermoplastic (Gmt) By Combined Conduction And Dual Beam Microwave Source Terms, Shrenik Kasturi May 1991

Numerical Simulation Of The Heating Of Glass Mat Thermoplastic (Gmt) By Combined Conduction And Dual Beam Microwave Source Terms, Shrenik Kasturi

Theses

Fabrication of parts from glass mat thermoplastic involves the heating of the composite to a temperature above the melting point of the matrix iesin to obtain a low viscosity and to allow sheets to be molded without fractui ing. The focus of this work is this heating stage, particularly the influence of a source term in the energy equation.

The solution to this physical situation is complicated by the nature of the GMT sheet, which has a layeied structure, with diffeient thermophysical properties in different layers. The use of source terms has not been reported yet. and is the piimary …


Successor Employers' Obligations Under The National Labor Relations Act, Ting-Wang Lu May 1991

Successor Employers' Obligations Under The National Labor Relations Act, Ting-Wang Lu

Theses

A wave of business acquisitions is currently sweeping the American corporate scene. Companies are purchasing both unionized and non-unionized businesses at a dizzying pace.

Not surprisingly, after years of confrontational contract renewals, management and 10 unions at the New York Daily News are jockeying for position in talks over agreements that expire on March 30, 1990. Throughout the long negotiation process then the strike began on October 25, 1990. End with Robert Maxwell, the British press baron, signing an agreement on his purchase of the Daily News on March 14, 1991. Obviously, this question of successor employers' obligations is one …


Workstation Allocation Schemes For Response Time Improvement In A Multiserver Pc Lan, Asit V. Merchant May 1991

Workstation Allocation Schemes For Response Time Improvement In A Multiserver Pc Lan, Asit V. Merchant

Theses

Microcomputer Local Area Networks have recently become quite popular. Higher demand in term of number of users who contribute a variable amount of load has led to Multiple File servers in a LAN. As a result of variable load, response time at workstations differ significantly depending not only on total load on the network but also on workstation distribution across servers. The goal of this study is to develop schemes to keep response time as low as possible and constant among workstations. This study is based on minimizing response time and containing it or keeping it constant by distributing workstations …