Electrical and Electronics Commons^™

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 …

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 …

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 …

Performance Studies Of Lapped Orthogonal Transforms, Frank E. Wadas

Theses

The comparative performance of several Lapped Orthogonal Transforms(LOTs) [1][2][3][12] is studied in this thesis . Blocking effects of conventional block transforms at low bit rates are reduced with LOT, through basis functions that overlap in adjacent blocks. The block transforms of Discrete Cosine Transform (DCT), Discrete Sine Transform (DST)[4], Discrete Legendre Transform (DLT), and the Modified Hermite Transform (MHT)[16] are extended to LOT in a way that a fast algorithm for nearly optimal LOTs is derived. The Markov and two different exponential correlation models are used as the source models for the derivation of these LOTs. It is shown that …

Optical Isolation Of Single Board Computer For Use In High Electrical Noise Environments, Meng Xiao

Theses

This thesis describes various electrical noises, noise environments and noise effects for electronic logic circuitry. The optical isolator is introduced and its concept, classification and characteristics are discussed.

Various design considerations are reviewed: input forward current, reverse breakdown protection, threshold, current transfer ratio, isolation voltage, data rate, common mode rejection, CMOS compatibility, isolation resistance, isolation capacitance, temperature effect and cost.

A multi-channel optical isolated input/output interface board for 8052AH BASIC SBC is designed. It includes 16 input channels, 16 output channels, decoder circuit, latching circuit, PC895 interface and input protection circuit. The sample board has been built, tested in the …

Temperature Dependent Current-Voltage Characteristics In Thin Sio2 Films, Jin Zhao

Theses

An analysis of the Fowler-Nordheim tunneling (FNT) theory and its application to temperature dependent current-voltage characteristics, of very thin films of SiO₂ on silicon, is presented. The final results are believed to provide the most complete examination of FN emission theory and predict the breakdown electric field in thin SiO₂ films. The role of the roughness, at the Si-SiO₂ interface, in determining the FNT current and breakdown mechanisms in metal-oxide-semiconductor (MOS) structures are also discussed.

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. …

A Code Verification System For Ink Jet Printing, Daniel Liang Hsu

Theses

This paper describes system integration of a code verification system. The system utilizes a feature matching

Non-Parametric Dominant Point Detection Algorithms, Kuo-Wei Huang

Theses

Dominant point detection is one of the most important preprocessing steps for landmark-based shape recognition and point-based motion estimation. Two new methods for detecting dominant points are presented. Both methods do not require any input parameter and the dominant points obtained by these methods remain relatively the same even when the object curve is scaled or rotated.

In the first method, for each boundary point, a support region is assigned to the point based on its local properties. Each point is then smoothed by a Gaussian filter with a width proportional to its determined support region. A significance measure for …

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 T_c 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 < ε_r < 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 ε_{r …}

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 …

Design Of An Ionized Cluster Beam System For Thin Film Deposition And Cluster Size Measurement, Steven K. Krommenhoek

Theses

This thesis describes a study of a unique deposition technique known as Ionized Cluster Beam (I.C.B.) deposition. According to I. Yamada and T. Takagi, the inventors of the I.C.B. concept, the beam of deposited material contains clusters as large as thousands of atoms. To study the mass distribution of the ionized species, an I.C.B. source was designed and built by the author. The design provided temperature control along the axis of the crucible by using electron beam heating with two independently controlled emission filaments. Special attention was given to minimizing the background of charged particles generated in various sections of …

Optimum Power System Planning, Youn Tae Kyong

Theses

This thesis presents analysis method of optimum power system planning. The Gauss-Seidel iteration method is used to calculate load flow data of power system. The real and reactive powers, voltage magnitude and phase angle at each bus were obtained using Gauss-Seidel iteration method for a given IEEE sample power system. The load flow calculations were repeated under 60 percentage, 70 percentage, 80 percentage, 90 percentage, 100 percentage loading condition.

The transformation of reference frames were performed to simplify given IEEE sample power system identification. The transformation of reference frame transforms real and reactive voltage, current and impedance variables(reference frame 1) …

An Mcs Basic-52 Sbc Using Anything But An 8052ah-Basic, Hyunyeop Lee

Theses

This thesis exploits the ways to develop a new MCS BASIC-52 SBC using anything but an 8052AH-BASIC microcontroller. The 8052AH-BASIC based SBC offers short development time and low system cost; it is advantageous for numerous applications especially in the instrumentation, measurement and process control. However, the 8052AH-BASIC is no longer officially supported by INTEL and could disappear. Also, this SBC is not adequate for applications where power consumption is an important factor because the 8052AH-BASIC, a MOS product, draws a considerable amount of current.

To solve these problems we demonstrate how the 8052AH-BASIC can be replaced by any of a …

Image Data Compression With Neural Networks, Jianjun Li

Theses

Three efficient image coding schemes, based orb neural networks, have been developed in this thesis: (1) Neural network vector quantization (NNVQ). The main advantage of this new technology is that it can accomplish the complex encoding process much faster than the previous algorithms. Its properties are studied and demonstrated by simulations. (2) A adaptive NNVQ for image sequence coding. Simulation experiments have been carried out with 4 x 4 blocks of pixels from an image sequence consisting of 40 frames. At 0.67 bits/pixel, this scheme achieves good image quality suitable for videoconferencing systems; (3) Neural network prediction. This new prediction …

Automatic Contour Extraction From Hvem Image Of Microvessel, Yong-Gang Liu

Theses

The research work reported in the thesis is motivated by the problem raised in the biomedical research utilizing high voltage electron microscope (HVEM) to study microvessels. There the contour data of cross-sections of microvessels are fed into some special electronic device to reconstruct three-dimensional pictures of microvessels. However, the contour data acquisition as routinely conducted by manual operation. This tedious procedure costs large amount of human power.

In this thesis, computer image processing techniques are applied to replace the time-consuming manual operation. A synthetic method is recommended. A software with various digital image processing functions has been developed and tested …

A Stereo Vision Technique Based On The Multi-Positioned Camera Criterion, Jie Bao

Theses

A modified feature based stereo vision [sic] technique is described in this thesis. The technique uses the curve-segments as the feature primitives in the matching process. The local characteristics of the curve-segments are extracted by the, Generalized Hough Transform.

A set of images of a scene, which are taken by a multi-positioned camera satisfying the parallelism criterion, are first filtered by the Laplacian of a Gaussian operator in different widths, i.e. coarse to fine channels. At each channel, the Generalized Hough Transform is applied to the curve-segments in each image. The curve position, the curve-length, the curve centroid, the average …

Token Bus Lan Performance : Modeling And Simulation, Ramesh Kurnool

Theses

A simulation model based on CSIM, a process oriented simulated language, to analyze the performance of the Token Bus protocol is developed. Performance measures such as throughput, average delay and maximum delay per packet are presented. System performance is analyzed for different loads, number of stations, network lengths, different physical and logical distribution of the stations with packet length as a parameter. Previous studies were based on the delay-throughput analysis with no discussion on the effect of variation of the logical and physical distribution of the stations on the performance of the model which is done in the present thesis. …

Fault Tolerant Benes Networks, Manoj Bhatnagar

Theses

A fairly large number of fault tolerant topologies have been proposed for the multistage interconnection networks in the recent years. However very few of these schemes have focused on the Benes network. This thesis presents two new fault tolerant architectures for the Benes network. The thesis includes algorithms to construct these fault tolerant networks from a Benes network and the reconfiguration procedure in the event of a fault. The hardware characteristics of both the fault tolerant networks have been analyzed and compared.

Formation And Characterization Of Thin Superconducting Y-Ba-Cu-O Films, Gyusuk Kim

Theses

Thin Y-Ba-Cu-O superconducting films were fabricated reproducibly on MgO (100) substrates by two different processes ; (1) deposition at a low substrate temperature fiom a single sintered YBa₂Cu_3.3O_x target using RF diode reactive sputtering followed by a post-annealing at around 830 ° C ; (2) deposition at the crystallization temperature under oxidizing atmosphere. The superconducting properties of films deposited by process (1) and (2) were studied. The variation of film composition and thickness as a function of distance from the target gas pressure and distance between target and substrate was studied. The Dependence of the …

Simulation And Design Of Field Emission Diode, Yun Yuan

Theses

A new generation of microelectronic devices utilizing vacuum field emission cathodes becomes surging interest in recent years. This paper concentrates on the study of the field emission diode — a basic vacuum microelectronic device. The field emission efficiency, current spatial distribution and time dispersion of conical tips and wedges of various geometrical shapes are compared and calculated by analytical methods and computer simulations. Two field emitter heating effects, namely the Joule heating and Nottingham effect, are discussed theoretically. All the simulation results in this paper are performed on 386 based personal computer. The limiting memory space of PC induced simulation …

Sputter Deposition And Characterization Of High Tc Superconducting Thin Films, Vipulkumar Patel

Theses

Preparation of thin superconducting films by direct RF sputter deposition on Si, MgO, SrTiO₃ and quartz substrates and silver and Sl3N4 buffer layers (deposited on silicon substrates) was studied. To study resistance versus temperature characteristics of thin films and bulk materials, a computerized measurement system was developed. 1-1.5 pm thick YBaCuO films deposited on Si₃N₄/Si were found to be insulating with room temperature resistance higher than 236KΩ, while films with Ag as a buffer and/or a passivating layer exhibited metallic behavior with room temperature resistances lower than 700mΩ. The area directly under the 2.25 inches …

Infrared Tv Camera With Ptsi Schottky-Barrier Detectors, Steven J. Blume

Theses

An infrared TV camera was developed for operating various sizes of Schottky-barrier IR-CCD image sensor chips. A digitally programmable frequency synthesizer is used so that the camera has the flexibility of using a 160 x 244 or 320 x 244 image sensor developed at the David Sarnoff Research Center. The outputs of the camera are compatible with an XYZ monitor, a standard TV monitor, and a computer workstation. Operation of the camera was demonstrated with a 160 x 244 image sensor producing an output on a standard TV monitor. Performance of the IR-TV camera system was investigated by evaluating CCD …

Uniformity Corrector And Signal Processing For A 160 X 244-Element Ir-Ccd Camera With Ptsi Schottky-Barrier Detectors, Paul D. Blume

Theses

An off-set-type, one point response uniformity corrector and the associated signal processing circuits was developed to be used for a 160 x 244-element IR-CCD camera with PtSi Schottky-barrier detectors. Image sensors with PtSi Schottky-barrier detectors exhibit two types of noise in the displayed video output, a temporal noise and a spatial fixed pattern noise. The performance of the image sensor, limited by the spatial noise which obscures low contrast detail and limits camera sensitivity, can be improved by a uniformity corrector. The uniformity corrector was constructed to substantially reduce the spatial noise in the output display by digitally subtracting a …

The Magnetotransport Analysis Of Hemt Structures At Low Fields, Naghmeh Nouri

Theses

On the basis of a study on numerous HEMT structures, a simple and useful technique was established for the characterization of 2DEG layers. This technique utilizes the magnetic field-dependence of the resistivity and Hall coefficient of the HEMT structure, to determine the values of the sheet density and mobility of 2DEG in the presence of other parallel conductive layers. This method of analysis was compared with previously used techniques such as Shubnikov-de Haas and the etch removal of the parallel conductive layers. Through this comparison and several measurements it was found that this procedure gives reproducible values for the 2DEG …

Adaptive Fir Digital Filter Design And Simulation In The Noise Reduction System, Jack Jiabing Pang

Theses

The adaptive FIR digital filter is designed to suppress the noise in the tape recording and audio communication systems. The cutoff frequency of the digital FIR filters can be varied adaptively depending on the energy level of the input signal. In audio communication, especially, in tape recording systems, the noise obviously gets much bigger, when the frequency band of the system increases. The noise reduction system makes use of a phenomenon called masking, where the big signal-to-noise ratio makes human ears not sensitive to the noise. In a constant interval time, the system detects the signal level and compares the …

The Design Of Decentralized Optimal Regulator Systems Using Matrix Minimum Principle, Sunny Lai Yick

Theses

This research considers the design of linear, time-varying regulator systems using Matrix Minimum Principle in the frame work of decentralized control theory. The regulator system is modeled in terms of state equation with multiple controllers. Each controller works cooperatively to optimize a common quadratic performance index. An additional constraint is imposed such that the controllers are linear time-varying functions of the outputs.

Necessary and sufficient conditions for optimality of the system are provided by the Matrix Minimum Principle and Hamilton-Jacobi Theory.

Two examples are developed to illustrate the concept.

Performance Analysis Of A Dynamic Reservation Multichannel Local Area Network, Abubakar A. Ibrahim

Theses

A reservation multiaccess protocol. is proposed to be used on multichannel local area networks. This protocol is advantageous for networks supporting integrated services. The delay and throughput performance for message transmission are obtained by analysist The delay performance of the protocol is similar to the M-CSMA/CD/IC multichannel network proposed by Marsan and Roffinella. It is found that the reservation protocol can provide better throughput-delay characteristics when the fraction of the total available bandwidth allocated to data is increased. It is also observed that the maximum throughput increases with the increase in the number of channels when the total bandwidth is …

Propagation Of Millimeter Wave Signals In Forests Using The Equation Of Radiative Transfer With Strong Forward Scattering Phase Functions, Nack Yang Cho

Dissertations

A forest is a highly scattering medium at millimeter wave frequencies. The propagation of cw millimeter wave signals in forests has been studied previously, both theoretically and experimentally. Published experimental data verified that continuous wave transmission is possible over lengths of the order of a few hundred meters and that a forest acts to strongly scatter energy in the forward direction. The cw studies yielded the determination of the range dependence, beam broadening effects and depolarization effects of millimeter wave signals in a forest. However, pulse broadening effects, which are of importance particularly in the case of digital signal transmission, …

Manufacturing Workstation Model Using Petri Nets, Reni Alexander

Theses

Petri nets have become a powerful tool for modeling and analyzing asynchronous concurrent systems. In this thesis I apply Petri nets for analyzing and modeling a flexible manufacturing workstation (FMS). A manufacturing workstation is modeled by using Colored- Timed Petri nets, with the consideration of tool handling, raw materials, quality checking and the reuse of reworkable scraps. A simulation program for a simplified Petri net model of manufacturing workstation is described and the production throughput is computed.