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Full-Text Articles in Electrical and Electronics

Neural Net Classification Of States In Finite State Vector Quantization, Zhigang Zhang Sep 1990

Neural Net Classification Of States In Finite State Vector Quantization, Zhigang Zhang

Theses

In this thesis, a new image coding technique based on Neural Network Finite State Vector Quantization(NNFSVQ) is presented. The new design takes advantage of the high interblock spatial correlation of pixels in typical grey-level images, in addition to intrablock correlation already exploited by vector quantization (VQ). Although many FSVQ require large memory space for the storage of the numerous state codebooks, the memory space requirement of NNFSVQ can be reduced by a very large factor (about 102-103) to manageable size without impairing image quality. Simulation experiments have shown that by using NNFSVQ the bit rate can …


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 …


Optimization Of Bandwidth Allocation In Atm Nets Through Simulated Annealing, Chien-Long Hou Sep 1990

Optimization Of Bandwidth Allocation In Atm Nets Through Simulated Annealing, Chien-Long Hou

Theses

Optimization of Bandwidth Allocation in ATM network is considered in this thesis. We address the problem of determining optimal bandwidth allocation in such BISDN's that adopt ATM as their basic switching. technique by using Simulated Annealing. Computer simulation shows that this optimal policy leads to the configuration which yields the minimum average packet delay.


Landmark-Based Shape Recognition By A Modified Hopfield Neural Network, Kuowei Li Sep 1990

Landmark-Based Shape Recognition By A Modified Hopfield Neural Network, Kuowei Li

Theses

In this thesis, we introduce a new thethod to achieve partial shape recognition by means of a modified Hopfield neural network. To recognize partially visible object, 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. Given a scene consisting of partially occluded objects, a model object in the scene is hypothesized by matching the landmarks of the model with those in the scene. A measure of similarity between two landmarks, one from a model and the other from the scene, is needed …


A Novel Schottky Barrier Mosfet For Vlsi Applications, Venkata S. Simhadri Sep 1990

A Novel Schottky Barrier Mosfet For Vlsi Applications, Venkata S. Simhadri

Theses

Schottky barrier MOSFETs are expected to offer certain fabrication advantages, low series resistance and the feasibility to go into sub-micron technology without having short-channel effects. A p-channel MOSFET using Schottky contacts as source and drain is reviewed theoritically. The limitations of the device arising from the oxide offset between source/channel is studied with the help of one dimensional simulation SEDAN. The process sequence leads to an offset between source and channel. The performance of the SBMOSFETs with and without offset is estimated using two dimensional device simulation program PISCES-II for PtSi and IrSi as source and drain material. A novel …


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 …


Comparative Analysis Of Single And Double Dwell Acquisition Schemes, Gurinder Singh Ahluwalia Aug 1990

Comparative Analysis Of Single And Double Dwell Acquisition Schemes, Gurinder Singh Ahluwalia

Theses

Single and double dwell pseudonoise (PN) acquisition systems are described, explained and analyzed. These systems are designed to synchronize a locally generated PN signal with a received PN signal of unknown phase in the presence of noise. The mean, variance and an approximate probability distribution function (PDF) of the acquisition time for the single and double dwell PN acquisition schemes is developed. Intuitively, the double dwell acquisition system should be superior to the single dwell system because of the ability to quickly dismiss incorrect cells and further verify probable hits. It is shown analytically that this is in fact true …


Design Of A Microengineered Pressure Sensor, Ranjeet Alexis Aug 1990

Design Of A Microengineered Pressure Sensor, Ranjeet Alexis

Theses

A new family of microengineered vacuum ionization gauges of an approximate volume of 200µ3 has been designed. These devices can he fabricated using existing semiconductor processing capabilities. The focus of this thesis is to scale down the current state-of-the-art for ionization sensors to micron dimensions. These gauges can be manufactured economically and potentially will be integrated with more complex structures and circuitry. In these devices an active ionization volume of micron dimensions is used for launching ions in a trajectory towards a collection electrode. Ionization of gas species is accomplished by an electron flux of sufficient energy. Analysis of …


Hardware Algorithms For Computing Transcendental Functions, Xin-Pei Gong Aug 1990

Hardware Algorithms For Computing Transcendental Functions, Xin-Pei Gong

Theses

The COordinate Rotation Digital Computer(CORDIC) is a special-purpose digital computer for real-time airborne computation. In this computer, a unique computing technique is employed which is especially suitable for solving the trigonometric relationships. A new computing technique based on the CORDIC algorithm is developed to reduce the number of iterations by one half for each input angle. This improvement is accomplished. by scanning multiple bits of the input angle(in our case, two) at a time. The CORDIC equations are rewritten accordingly and a hardware implementation structure is also presented. The results of the software simulation of the new algorithm are as …


Decomposing Non-Product Form Queuing Lattices Through Genetic Algorithm, Wei Han Aug 1990

Decomposing Non-Product Form Queuing Lattices Through Genetic Algorithm, Wei Han

Theses

In this paper, a Genetic Algorithm technique is adapted to decompose the state transition lattice of a class of non-product form queueing models. Genetic Algorithms are search algorithms based upon the mechanics of natural genetics. They combine a survival-of-the-fittest among string structures with a structured, yet randomized, information exchange to form a search algorithm with some of the innovative flair of human search. While randomized, genetic algorithms are no simple random walk. They efficiently exploit historical information to speculate on new search points with improved performance. Here genetic algorithms is applied to a non-product queueing lattices optimization problem. Only the …


Performance Evaluation Of Consumer Electronic Bus, Sairaj R. Pakkam Aug 1990

Performance Evaluation Of Consumer Electronic Bus, Sairaj R. Pakkam

Theses

This thesis describes the performance evaluation of the Consumer Electronic Bus proposed by the Electronic Industries Association. To study the behaviour of CEBUS under different traffic conditions, a simulation program was developed modelling the layer architecture of CEBUS. The CEBUS is based on the ISO/OSI model of layered architecture. The simulation results have shown that, when the throughput of the network is small, the delay is bounded for all messages of all priorities. As the throughput of the network increases, under the presence of more high priority messages, the lower priority messages get queued at their nodes. It is also …


Point Pattern Matching By A Genetic Algroithm, Minghwang Chen Aug 1990

Point Pattern Matching By A Genetic Algroithm, Minghwang Chen

Theses

The problem we consider is to find a subset of points in a pattern that best match to a subset of points in another pattern through a transformation in a least squares sense. Exhaustive search to find the best assignment mapping one set of points to another set is, if the number of points that are to be matched is large, computationally expensive. We develop a genetic algorithm which searches for the best ("almost the best") assignment efficiently. To map the point pattern matching into the framework of a genetic algorithm, we use a fitness function which inversely proportional to …


Conditional Artificial Dielectric Waveguide, Hsien-Wen Ho Aug 1990

Conditional Artificial Dielectric Waveguide, Hsien-Wen Ho

Theses

A thin layer of semiconductor ( the guest material ) is sandwiched between two polymeric films ( the host material ) to form an artificial dielectric waveguide. An artificial dielectric is a composite material consisting of a dielectric with a large number of conducting particles arranged in a three-dimensional pattern. The particle dimensions are smaller than the optical wavelength of interest. A beam of light with a photon energy above the band-gap of the semiconductor ( pump light ) induces electric and magnetic dipoles which affect the propagation of light with a photon energy below the band-gap ( probe light …


Small Disturbance Stability As Affected By Excitation Controls, Alfredo Flores Jun 1990

Small Disturbance Stability As Affected By Excitation Controls, Alfredo Flores

Theses

The effect of excitation control systems on the power system's small disturbance stability limits has been investigated in this thesis. Three excitation control schemes namely the proportional, fast?acting and the modified fast?acting have been studied.

The stability results were predicted directly in terms of the AVR gain controlling parameters following one?dimensional and two?dimensional frequency domain separation technique. The necessary algorithms and computer simulation programs have been developed.

In case of a modified fast?acting excitation control with three unknown variables, a procedure has been proposed to obtain the stability results by extending the two?dimensional frequency domain separation technique.


Damage Effects To Si-Sio2 Structures Due To Reactive Ion Etching, Moshe D. Bunyan Jun 1990

Damage Effects To Si-Sio2 Structures Due To Reactive Ion Etching, Moshe D. Bunyan

Theses

This thesis presents the damage effects to the Si ? SiO2 structures due to Reactive Ion Etching (RIE). The research was carried out on Si ? SiO2 MOS capacitors which were fabricated using RIE and wet etch (Hydrofluoric acid etch (HFE)) Process. The experiment was carried out using CV technique and Ellipsometry. Various electrical parameters were measured from CV *curves of these MOS capacitors. It was observed that the CV curve obtained for the RIE etched sample showed considerable deviation from that of the control sample. This indicates the presence of excess of interface trap charge density which …


Improving Solids Conveying In Plasticating Extruders : An Investigation Into Manufacturing Processes And Manufacturing Systems For Profiled Thermoplastic Pellets, Oommen Cherian Jun 1990

Improving Solids Conveying In Plasticating Extruders : An Investigation Into Manufacturing Processes And Manufacturing Systems For Profiled Thermoplastic Pellets, Oommen Cherian

Theses

The objective of the thesis is the manufacture of thermoplastic bilobal and trilobal profiled pellets for the determination of the interparticulate co-efficient of friction exhibited by solid beds of such pellets. The enhancement of the interparticulate coefficient of friction is expected to lead to ameliorated solids conveying rates in plasticating extruders.

Predicting the product shape from a profile die is very difficult due to the elastic memory of plastics and the complex boundary conditions. Consequently the cost involved in experimenting with different profile dies is high. Therefore a standard die with several die inserts of varying cross-sections were used to …


Effect Of Moisture On Microcircuit Failure, Chandrabala D. Patel Jun 1990

Effect Of Moisture On Microcircuit Failure, Chandrabala D. Patel

Theses

Stability and reliability of microcircuit is dependent on its design, fabrication, testing, storage and use.

In this thesis emphasis is given on various failure mechanisms of Integrated Circuits in humid environment and techniques of improving reliability. Other factors which affect the failure of integrated circuits are also discussed. Moisture induced failure modes, semi-reversible failures and irreversible failures (surface leakage current and corrosion-causing interruption of interconnection lines) are also reviewed.

Controlling the contaminants and moisture related corrosion are also covered. The quickest way to evaluate the reliability of microcircuit is by accelerated aging test and by selection of meaningful criteria of …


A Study Of Signal Cancellation Effects In Adaptive Arrays, Cheng-Der Sun May 1990

A Study Of Signal Cancellation Effects In Adaptive Arrays, Cheng-Der Sun

Theses

An adaptive array can automatically place pattern nulls in directions from which undesired signals (interference, jamming, or clutter, etc.) arrive and can also provide gain for a desired signal. The purpose of this study was to study the effects of the adaptive array on the desired signal while suppressing the undesired signal.

This was done by studying the transfer characteristics of the adaptive array between its input and output. In this study, C.W. jammers along with the desired signal were considered and input and output relationship of the adaptive array were determined. Several basic types of adaptive arrays were studied …


Memory Card Memory Read-Out Module For 8052ah Basic Single Board Computer, Yongyi Sun May 1990

Memory Card Memory Read-Out Module For 8052ah Basic Single Board Computer, Yongyi Sun

Theses

A Memory Card Memory Read-out Module is described that is used to collect the data stored in the RAMs of 8052AH BASIC SBCs and transfer it to the storage of another system called stationary recall unit.

The motivation for this system is as follows:

Automatic Rail Diagnostic System (ARDS) of New Jersey Transit Rail Operation (NJTRO) will revolutionize the maintenance of rail cars by monitoring selected on-board subsystems and components. The on-board unit of ARDS is a data gatherer. It can collect data describing the status and performance of selected on-board operating subsystems and components. A 8052AH BASIC SBC is …


Cryogenic Characterization Of Potential High Temperature Superconducter Substrates At Microwave Frequencies, Sukhmani Kaur May 1990

Cryogenic Characterization Of Potential High Temperature Superconducter Substrates At Microwave Frequencies, Sukhmani Kaur

Theses

The lack of characterization data for dielectric substrate materials at microwave frequencies and cryogenic temperatures hinders the development of high Tc superconducting circuits. Low loss (tanδ < 10-4) substrates with dielectric constants in the range of 5-100 at cryogenic temperatures are needed to realize the advantages of superconductor circuits. Measurement techniques previously reported are either time consuming or inaccurate. We report an adaptation of Courtney's method for accurate, simple evaluation of complex dielectric constants (10 < εr < 100) at low temperatures. The fixture was calibrated using known properties of polycrystalline ZrSnTiO4. We measured er and tans on three potential substrate materials, Al2O3, MgO, and LaAlO3 at 5-10 GHz in the temperature range 77-300K. No temperature hysteresis in either εr …


A Theoretical Model For Radio Attenuation Inside Buildings, Kyu-Sung Kim May 1990

A Theoretical Model For Radio Attenuation Inside Buildings, Kyu-Sung Kim

Theses

Research to expand the capability of indoor, portable, radio frequency links for voice and data transmission is being pursued worldwide. Sophisticated communication systems using digital portable radio telephones have been proposed. To accomplish this goal, it is necessary to ascertain the attenuation of electromagnetic signal propagation inside buildings. Because modeling of the indoor environment at radio frequencies is very complicated, most publications document experimental results. In this study,. a theoretical model is proposed for predicting path loss inside buildings. The theory involves a waveguide model of the indoor environment which permits a rigorous modal solution similar to that developed by …


Delay Improvement And Reliability Enhancement In A Cim-Based Factory Network, Vimalkumar Upadhya May 1990

Delay Improvement And Reliability Enhancement In A Cim-Based Factory Network, Vimalkumar Upadhya

Theses

Today, Computer-Integrated Manufacturing (CIM) refers to the integration of computer-controlled factory floor devices with engineering design and plant management computers. In general, there is a need for more efficient factory networks than are currently available. To this end, it is essential to investigate new network architectures and study their performance.

A number of CIM networks are analyzed in this thesis, and a new CIM network architecture is proposed. The throughput and delay characteristics of all these network architectures are derived from their respective simulation models. The results indicate that the proposed CIM network architecture has superior performance characteristics, compared to …


Temperature Dependent Current-Voltage Characteristics Of Tisi2/N+/P Silicon Shallow Junctions, Bhupendra M. Shah May 1990

Temperature Dependent Current-Voltage Characteristics Of Tisi2/N+/P Silicon Shallow Junctions, Bhupendra M. Shah

Theses

Analyses of temperature dependent current-voltage characteristics, of titanium silicide films on n+/p silicon shallow junctions, has been presented here. The fabrication technique involves the formation of shallow pn junctions, by ion-implantation of As+ through titanium films evaporated on P type silicon. The improvement of the activation of dopants has been fulfilled by different annealing processes in conjunction with the dopant drive-in. Electrical measurement of temperature dependent current-voltage technique has been employed to characterize these devices. The temperature dependent factors such as energy bandgap narrowing, majority carrier degeneracy, diffusivities, mobilities and minority carrier life time are evaluated by using key approximations.


Multi-Sensor System For An Articulated Robot Hand, Narendra Sucahyo May 1990

Multi-Sensor System For An Articulated Robot Hand, Narendra Sucahyo

Theses

The precision and dexterity of a manipulator hand critically depends on the proper extraction and processing of sensory information. This thesis describes how a sensor system equipped with fingertip sensors and strain gauges can provide proper feedback to drive the grasp kinematics of an articulated robot hand. The grasp kinematic that provide the manipulator hand with precision and dexterity is based on impedance control. The fingertip sensors and the strain gauges are constructed of piezoresistive materials for force transduction. Through optimization, based on the sensitivity and capability of the sensors, a synergism of force and contact information can be obtained …


Design And Processing Of Micromechanical Sensor Devices, Zhixiong Joe Zhou May 1990

Design And Processing Of Micromechanical Sensor Devices, Zhixiong Joe Zhou

Theses

A multi-purpose cantilever beam and microbridge accelerometer structure has been designed and fabricated in this work. This same structure with modification can be employed as a capacitive accelerometer, mechanical resonance accelerometer, and a piezoresist accelerometer. Surface microengineering processing techniques have been developed in this work. The cavity structure significantly reduced the parasitic capacitance. This work reports the first instance of spin-on glass for rnicromechanical device applications as both a sacrifical layer and a planarization material for the cavity. Other results of this thesis including:

1. LPCVD low temperature oxide as the base material from which the cavity is etched;

2. …


Interconnection Of X.25 Networks, Syed Ayaz Qutubuddin Ahmed May 1990

Interconnection Of X.25 Networks, Syed Ayaz Qutubuddin Ahmed

Theses

The purpose of this work was to investigate the performance of two interconnected X.25 networks via CCITT internet protocol X.75. Since internet protocol X.75 follow the same flow approach as X.25, we are allowed to model the acknowledgement queue in such a way that this queue provides a feed back path from destination to the source queue. Thus we are able to model our interconnected network as a closed queueing network with limited number of packets in transit within the network. Mean Value Analysis with Blocking (MVA) algorithm was applied to obtain the performance characteristics as the resources available were …


An Implementation Of Mht Algorithm For Adaptive Transform Coding Of Speech, Peter Battenschlag May 1990

An Implementation Of Mht Algorithm For Adaptive Transform Coding Of Speech, Peter Battenschlag

Theses

The Modified Hermite Transform (MHT), a suboptimum block transform scheme, is implemented on a TMS320C25 signal processing system with the objective of reducing the redundancy in speech signals and transmit a quantized vector representation at bitrates as less as 0.5 bits per sample.

The generation of the Hermite polynomials with a binomial and several first order IIR filter structures is presented focusing on the fact that no muliplications are required which simplifies the MHT algorithm considerably.

An assembler program performs forward and inverse transformation together with a vector quantization using adaptive bitallocation based on short-time statistics for the transform coefficients. …


Multichannel Input Moniter, Geng Lin Chen May 1990

Multichannel Input Moniter, Geng Lin Chen

Theses

In order to communicate ,with each other, people must use the same kind of language. MIDI, the Musical Instrument Digital Interface, was established as a hardware and software specification which makes the communication between musical instruments become possible.

What this thesis does is interfacing a musical instrument with other devices using MIDI protocol. The hardware is a multichannel priority interrupt system which has already been done and was included in the discussion of this thesis. The focus of this thesis is concentrated on the software development of multichannel input monitor.


Configuring Maps For A Satellite Communication Network By Self- Organization, Yizhong Chen May 1990

Configuring Maps For A Satellite Communication Network By Self- Organization, Yizhong Chen

Theses

There are several management tasks in a telecommunication network. Among which traffic management is one of the most important and difficult tasks. It is concerned with maximizing network efficiency when the network is under stress either due to overload or failure. New attempts to automate this task such as expert system based approach are yet to be perfected. In this thesis, we advocate a new concept of traffic management. Our scheme consists of two levels. At the first level, we introduce a Self-organization model to dynamically configure a map for a satellite communication network. The second level is a routing …


A Micro-Based Machine Vision System, Hsueh-Chung Michael Feng May 1990

A Micro-Based Machine Vision System, Hsueh-Chung Michael Feng

Theses

In this thesis, a low-cost general purpose machine vision system based on a personal computer of the PC-XT/AT family and an electronic camera controller based upon a Motorola 6811C11 single-chip microcontroller has been designed and implemented. This work is focused on image formation. The system supports a long distance camera-computer configuration. A picture editor, generic image manipulation software was designed and implemented. A single computer can supervise multiple cameras.