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Provocations: Raw Constructs In Mixed Media, Heinrich Klinkon Nov 1990

Provocations: Raw Constructs In Mixed Media, Heinrich Klinkon

Theses

None provided.


A 512 X 512 Random Addressable Variable Resolution Image Sensor, Chakravarthy Yarlagadda Oct 1990

A 512 X 512 Random Addressable Variable Resolution Image Sensor, Chakravarthy Yarlagadda

Theses

This thesis presents the design and layout of a 512 x 512-element with 20μm x 20μm pixels image sensor that emulates the properties of the human eye and is useful in high speed processing of visual data for machine vision applications. The imager will be able to operate with random-address selection in variable resolution or with multiple regions of interest to reduce the number of pixels readout. The selection of the pixels is done by x-y addressing the MOS switches which connect the photodiode pixel to the output through the sense lines. The design of column decoder and row decoder …


Photo-Induced Electrochemical Etching Of Inp Semiconductor In A Thin Film Cell, Bungsu Iskandar Oct 1990

Photo-Induced Electrochemical Etching Of Inp Semiconductor In A Thin Film Cell, Bungsu Iskandar

Theses

The Photo-Induced Electrochemical Etching of n-InP wafer in aqueous solution is investigated for both reservoir and capillary systems. A sinusoidal spatial variation of light intensity pattern is directly illuminated and promoting etching on an InP semiconductor wafer. The etching process is time-efficient, and produces highly isotropical and a promising high resolution pattern. It gives a good reproducibility and has less contaminating features. Its features may be explained by a non-linear relationship between the electrolyte concentration and the photo-generated holes density at the interaction surface. An optimal reaction rate is determined by the ratio of the reactivity to ionic diffusion, either …


The Dynamics Of Bicycling : An Analytical And Experimental Investigation To Determine The Principles Of Design, Sylvester Yen Oct 1990

The Dynamics Of Bicycling : An Analytical And Experimental Investigation To Determine The Principles Of Design, Sylvester Yen

Theses

Bicycles have existed in working order for a century. They are mechanical products whose dynamic characteristics are highly nonlinear. This has to some extent prevented detailed analysis and for the most part design has been made from practical experience. The advent of computers has markedly changed the techniques and procedures used to calculate the performance of a bicycle. Bicycling began long ago, and since the first bicycle was demonstrated, bicyclists, scientists and engineers have designed thousands of different bicycles considering safety, comfort to ride and ease of control. Nonetheless, nobody claims to fully understand bicycling. If the fundamental principles exist, …


Rotary Micromotor Design With Ic-Compatible Processing, Hong Yu Oct 1990

Rotary Micromotor Design With Ic-Compatible Processing, Hong Yu

Theses

Several microelectromechanical rotary motors have been designed and simulated with varying rotor and stator configurations. All of these micromotors operate with an electrostatic power source and have rotor diameters varying from 0.2 to 0.4 mm. These micromotors develop torques in the range 8 to 50 picoNewtons with rotors of polysilicon with 2 micron film thickness based on the detailed simulations of this thesis using a 3-phase voltage power source. The geometries modelled in this work are side-drive and vertical-drive configurations. These micromotors obtain drive torque from the fringe-field differential at the periphery of the rotor poles.

Unlevitated micromotors (with bearings) …


Modeling A Fuel Rich Premixed Laminar Methane Flame Oh, Ch, Nh, Cn Profiles, Including Prompt No, Md. Hasan Ul Karim Oct 1990

Modeling A Fuel Rich Premixed Laminar Methane Flame Oh, Ch, Nh, Cn Profiles, Including Prompt No, Md. Hasan Ul Karim

Theses

A detailed reaction mechanism based upon fundamental thermochemical kinetic principles has been developed to describe the concentration profiles of OH, CH, NH, CN, and NO including prompt NO radicals in laminar flow, fuel rich methane flames as well as flames doped with 700 ppm ammonia. A one dimensional laminar flat flame code which incorporated diffusion, and the detailed reaction mechanism was used to predict the radical concentration profiles from the model. These calculated values are compared to experimental data of Dean (1984).

The model consist of two reaction subsets, hydrocarbon oxidation set and an ammonia oxidation set. The reactions most …


Shaping Wood/Naming Shapes, Robert Thomas Leverich Oct 1990

Shaping Wood/Naming Shapes, Robert Thomas Leverich

Theses

None provided.


Aggression And Symbols Of Power, Karen Kuhn Oct 1990

Aggression And Symbols Of Power, Karen Kuhn

Theses

Weapons are one of the oldest and most significant forms of artifacts, occurring in virtually all human cultures. Weapons and their technology often determine power structures, not only by brute force of arms, but by long standing respect to ritual aggression. In many cultures, weapons have become abstracted and formalized to become symbols of power and authority, as in a ruler 's scepter, which is a glorified war club. Jewelry functions in much the same manner, proclaiming the social status of the wearer, although in the western world, we have lost most of the symbolic meaning of our jewelry; for …


Kinetic Studies Of Dna Interstrand Crosslink By Nitrogen Mustard And Phenylalanine Mustard, Margaret I. Kaminsky Oct 1990

Kinetic Studies Of Dna Interstrand Crosslink By Nitrogen Mustard And Phenylalanine Mustard, Margaret I. Kaminsky

Theses

Phenylalanine mustard (PAM) and nitrogen mustard (HN2) are bifunctional alkylating agants which covalently crosslink DNA. Their crosslinking ability forms the basis of their usefulness as anti-cancer drugs since crosslinked DNA cannot replicate and thus the cancers cells cannot reproduce. Despite apparent similarities, the two drugs are known to have important differences. PAM is more effective against cancer and has fewer side effects. In reactions with cell cultures, PAM produces crosslinks more slowly, but the crosslinks are more persistant The experiments reported here offer kinetic explanations for the differences. In vitro time-dependent crosslinking reaction profiles for HN2 and PAM produced using …


A Detailed Mechanism For Initial Phases Of Oxidation And Pyrolysis Of Methyl Tert-Butyl Ether (Mtbe), Wen-Chiun Ing Sep 1990

A Detailed Mechanism For Initial Phases Of Oxidation And Pyrolysis Of Methyl Tert-Butyl Ether (Mtbe), Wen-Chiun Ing

Theses

The lead phasedown in gasoline in both the U. S. and in Europe, the failure of other nonlead oxygenates (e.g. ethanol...) to significantly improve octance ratings and therefore to serve as replacement for tetra ethyl lead in gasline, and the U. S. Environmental Protection Agency's restrictions on gasoline RVP (Reid Vapor Pressure) to decrease tropospheric ozone concentrations are the factors causing the rapid growth in MTBE demand. There is however no detailed chemical kinetic study on the thermal or oxidative reactions of MTBE for full understanding the behavior and characteristics of MTBE and its degradation products during combustion processes.

Detailed …


Design Of A Cmos Temperature Sensor With Eeprom Error Correction Scheme, Jin-Ku Kang Sep 1990

Design Of A Cmos Temperature Sensor With Eeprom Error Correction Scheme, Jin-Ku Kang

Theses

This thesis describes the design and operation of a CMOS temperature sensor operating at very low power with an EEPROM error correction scheme including the physical layout. This device is designed for applications requiring very low power including biomedical and optically powered device applications. The sensor output is an analog voltage. The temperature sensing cell is implemented with two BJTs having different emitter areas. An op amp dissipating about 300 micro-watts power is designed and is used to amplify the sensor output voltage with a gain of 85dB. A novel EEPROM is used to correct nonlinearity error of the temperature …


A Transputer Based Distributed Graphics Display, Ramana V. Kattula Sep 1990

A Transputer Based Distributed Graphics Display, Ramana V. Kattula

Theses

The design of a transputer based graphics display is discussed. The problems associated with the single processor graphics systems are described. A solution based on multiple transputers is proposed. The transputer based graphics display described is a general purpose graphics system which can achieve any required compute performance and drawing performance without using special hardware. The display resolution and color depth can be enhanced as per the user requirements with little or no change in hardware.


Simulation And Analysis Of Priority Classes In Extended Token Based Local Area Networks, Bhavinkumar R. Pathak Sep 1990

Simulation And Analysis Of Priority Classes In Extended Token Based Local Area Networks, Bhavinkumar R. Pathak

Theses

Recently, Local Area Networks carrying multiple priority classes of messages have received considerable attention. The IEEE 802.5 token ring standard defines an optional priority scheme to handle different priority classes of messages. A simulation model of symmetric priority based networks, consisting of token ring networks interconnected by a bridge is considered. Messages are divided into two priority classes, namely, high priority traffic and low priority traffic. High priority traffic is guaranteed access on the channel, whereas low priority messages are served when the system determines that no high priority messages are currently waiting. The simulation results are used to evaluate …


A Self Testing Strategy For The Wafer Scale Hierarchical Memory Architecture, Maremanda V. R. Rao Sep 1990

A Self Testing Strategy For The Wafer Scale Hierarchical Memory Architecture, Maremanda V. R. Rao

Theses

Since the early 1960's, semiconductor chips have matured from single transistor devices to one million transistors per chip. The integration has been achieved by reducing transistor dimensions, and by increasing chip sizes. However, physical limits are being reached as submicrometre dimensions are approached. Fault tolerance has to be used to maintain the increase in the chip complexity. Yield improvement is only one of the many possible gains of fault tolerance. The dense integration of logic on a single chip also creates a huge test problem. in recent years a great deal of effort has gone into the development of yield …


Microengineered Thermal Conductivity Vacuum Pressure Sensor, Sanjay Talreja Sep 1990

Microengineered Thermal Conductivity Vacuum Pressure Sensor, Sanjay Talreja

Theses

This thesis details the first designs for microengineered vacuum pressure gauges based on silicon microelectronic technology. A monolithic polysilicon air-bridge structure (supported at both ends), within a Wheatstone bridge circuit, is used as a pressure sensor. The device utilizes the change of the thermal conductivity of a gas with ambient gas pressure. The doubly supported beam functions as a temperature sensitive resistor with a negative temperature coefficient of resistivity. Thermal change of resistance monitored as a measure of ambient pressure constitutes the basis of operation for this sensor. The sensor operates over the pressure ranging from 1 Torr to 10 …


Simulation And Analysis Of Integrated Lans For Hospital Environment, Naveen K. Verma Sep 1990

Simulation And Analysis Of Integrated Lans For Hospital Environment, Naveen K. Verma

Theses

Hospitals generate a large number of data sets of different types and formats and it is required to integrate these data sets for their rapid and simultaneous communication in order for a better treatment of patients and to cut the escalating costs. A better approach to meet this requirement is to have a distributed system linked all together with a high capacity LAN using an efficient integration method.

This thesis begins by studying the characteristic feature and suitability of Queued Packet & Synchronous Exchange (QPSX) network architecture. The network models are simulated for QPSX, Ethernet and Token Bus networks for …


Microengineered Silicon Beam Switch For Fiber Optics, Hsu-Nien Yang Sep 1990

Microengineered Silicon Beam Switch For Fiber Optics, Hsu-Nien Yang

Theses

A novel microelectromechanical actuator has been designed for moving an optical input fiber into alignment with one of three stationary output fibers. This switching device thus can connect an input optical port to one of 3 selected optical ports. The actuation force is created by a vertical-drive armature measuring 0.5x2.7 mm2 mechanically tethered to the input optical fiber. A force of 2.33 mN is obtained from the linear acturator when the vertical stator armature gap is one micron and the applied three phase voltage is 140 Volts. The required force is a function of the input fiber length, e.g. …


Max/Min : A Novel Rank Order Based Filter Family, Raafat E. Kamel Sep 1990

Max/Min : A Novel Rank Order Based Filter Family, Raafat E. Kamel

Theses

In the early development of signal and image processing, linear filters were the primary tools. Their mathematical simplicity made them easy to design and implement. They also offered satisfactory performance in many applications. However, they show poor performance in other cases, such as image processing.

Nonlinear filtering offered a solution to these problems. Nonlinear filtering has undergone a lot development for a long time. Among the first known nonlinear filters was the median filter, which was proposed by Tukey. Median filter preserves signal or image details better compared to a linear filter. Later other nonlinear filters were developed, including median …


Recycling: Separation Of Major Thermoplastics From Postconsumer Plastics Stream, Rafael A. Rodriguez Sep 1990

Recycling: Separation Of Major Thermoplastics From Postconsumer Plastics Stream, Rafael A. Rodriguez

Theses

The complete process for separating Low Density Polyethylene (LDPE), High Density Polyethylene (HDPE), Polyvinyl Chloride (PVC), Polypropylene (PP), Polystyrene (PS), Polyurethane (PU), and Polyethylene Terephthalate (PET) from a mixture of postconsumer plastics materials was presented. The driving forces considered to achieve separation were different densities and selective solubility of plastics in specific solvents.

The proposed process separates Polyurethane and Polystyrene by using aqueous solutions of different densities. On the other hand, the other five plastics are separated using solvents.

Diagrams showing streams and plastics separation in each unit were discussed. Individual material balances for each step were performed for a …


Implementation Of Parallel Sorting Algorithms On A Transputer Network, Venkatraman U. Calidas Sep 1990

Implementation Of Parallel Sorting Algorithms On A Transputer Network, Venkatraman U. Calidas

Theses

Many sorting algorithms, such as the bubble sort and the binary tree selection sort, are n-squared algorithms and take O (n2) time to sort n values. These can be easily parallelized; the resulting sorts are called the odd-even transposition sort and the parallel tree selection sort, respectively. These have O(nlogn) time complexity. The quicksort is an O(nlogn) algorithm and it can parallelized to make it an O(logn) algorithm.

A transputer is a microprocessor which has serial links to transmit and receive data from other transputers. The above algorithms are implemented on a network of transputers and the link connections for …


International Technology Transfer : America Via China, Lijie Dong Sep 1990

International Technology Transfer : America Via China, Lijie Dong

Theses

Momentous changes continue to occur in China. The high priorities now accorded economic modernization and improved global relations present a sharp contrast to the years of the Cultural Revolution and earlier. But what happened last year, the June 4 Tiananmen Square massacre, brought about great confusion and uncertainty over China's future course. China may be a constructive trading and strategic partner, or it may choose a more divergent path. U.S. decisions on technology transfer will be an important determinant of which path is followed and the implications for the world.


An Optically Powered Cmos On-Chip Power Supply, Jaeyong Jeong Sep 1990

An Optically Powered Cmos On-Chip Power Supply, Jaeyong Jeong

Theses

This thesis presents an optically powered CMOS on-chip power supply for CMOS IC applications. There exists a need for specialized chips that are located remotely and are powered by light supplied through fiber-optic cabling. An optically powered CMOS on-chip power supply circuit described in this thesis is composed of three subcircuits; light to voltage converter circuit, clock pulse generator circuit, and voltage multiplier circuit. Each subcircuit has been analyzed and designed, and simmulated using SPICE 2G.5/6 with 3pm CMOS SPICE parameters from the MOSIS. The circuits layout has been done using MAGIC according to the MOSIS scalable CMOS design rules. …


Landmark-Based Partial Shape Recognition By A Two-Stage Bam Neural Network, Xianjun Liu Sep 1990

Landmark-Based Partial Shape Recognition By A Two-Stage Bam Neural Network, Xianjun Liu

Theses

In this thesis, we develop a Bitfirectional Associative Memory (BAM) based neural network to achieve partial shape recognition. To recognize objects which are partially occluded, we represent each object by a set of landmarks. The landmarks of an object are points of interest relative to the object that have important shape attributes. To achieve recognition, feature values (landmark values) of each model object are trained and stored in the network. Each memory cell is trained to store landmark values of a model object for all possible positions. Given a scene which may consist of several objects, landmarks in the scene …


Characteristic Shape Recognition With Fuzzy Dustering, Kalpesh J. Patel Sep 1990

Characteristic Shape Recognition With Fuzzy Dustering, Kalpesh J. Patel

Theses

The problem of shape detection has been treated as one of clustering. A fuzzy-shell clustering(FSC) has been formulated as non linear least squares with fuzzy memberships as weights. An improved FSC algorithm has been proposed based on this formulation to partition the input feature vectors into hyper-spheres. To illustrate the usefulness of improved FSC we have provided numerous examples in 2-D space. The idea has been extended to fuzzy ellipsoidal-shell clustering (rESC). A FESC algorithm has been proposed to partition the input feature vectors into ellipsoidal patterns. To substantiate our claims regarding usefulness of this algorithm we have provided many …


Investigation Of Micromechanical Properties Of Tungsten Silicide Thin Films, Bharat Pathak Sep 1990

Investigation Of Micromechanical Properties Of Tungsten Silicide Thin Films, Bharat Pathak

Theses

Micromechanics is a field which is maturing. Recent research interest in micromechanical structures has focussed on the fabrication of microactuators and microsensors. These microsensors and actuators can sense very small changes in the environment without disturbing the equilibrium of the environment. The refractory silicides are some of the compatible materials used to integrate the micromechanical structures and the interfacing electronic circuits on the same chip. As a result of this, the thermodynamic, electrical and mechanical properties of transition metal silicides should be given a closer look for micromechanical applications.

This thesis details the design and fabrication of tungsten silicide moveable …


The Interconnection Network Analysis Package, Nadeem Sabbar Sep 1990

The Interconnection Network Analysis Package, Nadeem Sabbar

Theses

This thesis focuses on the development of the Interconnection Network Analysis Package (INAP), and the use of INAP to analyze minimal permutation networks. The INAP code is written in C language using Turbo C compiler. Although the INAP has been used to analyze the subject networks it is not a dedicated system. It gives the user the freedom to create the permutation network from scratch (1-8 inputs and 1-7 stages), and then to process it for any number of stages.

The INAP made the analysis of five input networks easy and efficient. The networks have been analyzed stage by stage. …


Design And Simulation Of Submicron Microelectronic Vacuum Triodes, Hou-Jun Wang Sep 1990

Design And Simulation Of Submicron Microelectronic Vacuum Triodes, Hou-Jun Wang

Theses

This thesis presents the first design and detailed Simulation of submicron vacuum microelectronic triodes static characteristics. In this thesis a new 5-electrode active device is emphasized.

These devices have potentially important advantages over semiconductor devices. They can be used in extreme environments. The picosecond transit time for internal electron ballistics provide optimism for very fast devices applications. It appears reasonable to fabricate these devices using standard VLSI processing equipment. Further, the micron dimension makes " vacuum microelectronic chips" a reasonable goal.

Devices are characterized for static parameters including electron trajectories, electric field contours, and voltage potential contours. The field emission …


Modeling And Analysis Of Electrical Properties Of Polycrystalline Silicon Films, Yunsheng Wang Sep 1990

Modeling And Analysis Of Electrical Properties Of Polycrystalline Silicon Films, Yunsheng Wang

Theses

In recent years, investigations on polysilicon grain structures have shown that all polysilicon films by LPCVD which are most used in today's integrated circuits are columnar in structure. In this work, a square columnar grain structure has been considered to model electrical properties of polycrystalline silicon films instead of all previous one-dimensional grain structure models. By solving Poisson's equation with certain boundary conditions, we find that the barrier height at the corners of the grain is lower than that in the one-dimensional case. Assuming the trapping state energy level as constant, we also find that this level has a value …


Monolithic Induction-Sourced Ac-To-Dc Power Supply Design, Jianhua Chen Sep 1990

Monolithic Induction-Sourced Ac-To-Dc Power Supply Design, Jianhua Chen

Theses

This thesis describes techniques with design nomographs for supplying power to CMOS and microelectromechanical implanted devices. These applications require voltages in the range of 5 to 50 volts. Different kinds of voltage multiplier circuits were used to achieve high voltage output. The AC-to-DC and DC-to-DC capacitive bootstrap voltage multipliers are designed and analyzed. The AC-to-DC and DC-to-DC inductive bootstrap voltage multiplier circuits are presented and the SPICE simulations are done with those circuits. Four different options of inductive link high voltage power supply are presented, analyzed and compared. The link parameters of two VLSI-compatible square-shaped coils are calculated in both …


Ligament Reconstruction : A Biomechanical Cadaveric Test Of Autogenous Repairs And The In Vivo Evaluation Of Synthetic Scaffold Materials, Anne Marie Daly Sep 1990

Ligament Reconstruction : A Biomechanical Cadaveric Test Of Autogenous Repairs And The In Vivo Evaluation Of Synthetic Scaffold Materials, Anne Marie Daly

Theses

The knee joint is the largest and one of the most complex joints in the human body. The anterior cruciate ligament (ACL) is one of the major intra-articular ligaments responsible for controlling and guiding the knee through most of its range of motion and its rupture alters normal joint mechanics.

One objective of this thesis was to determine if two autogenous tissue ACL reconstruction methods were biomechanically equivalent. The first method using the central one-third of the patellar tendon has been used clinically since the early 1960s. The second method utilizes portions of both the semitendinosus and the iliotibial band. …