Engineering Commons^™

Fast Point Pattern Matching By Heuristic And Stochastic Optimization Techniques, Ashish Agrawal

Theses

This work is concerned with one of the methodologies used in the final stages of machine vision: the matching of model point patterns to observed point patterns. Conventional search methods not only fail to arrive at the optimal match, but are also computationally expensive and time consuming. To arrive at the optimal pattern match, stochastic and heuristic optimization as the search technique, exploiting Simulated Annealing (SA), Evolutionary Programming (EP) and Mean Field Annealing (MFA), are explored in detail. A comparison of results obtained using SA versus "hill-climbing" and "exhaustive search" techniques, and results of EP are presented. The relative effectiveness …

An Adaptive Fusion Model For Distributed Detection Systems With Unequiprobable Sources, Yuzheng Zhang

Theses

In a traditional communication system, a single sensor such as a radar or a sonar is used to detect targets. Since the reliability of a single sensor is limited, distributed detection systems in which several sensors are employed simultaneously have received increasing attention in recent years. We consider a distributed detection system which consists of a number of independent local detectors and a fusion center. Chair and Varshney have derived an optimal decision rule for fusing decisions based on. the Baysian criterion. To implement such a rule, the probability of detection P_D and the probability of false alarm …

Fabrication Of Micron-Sized Mirror/Cantilever Silicon Devices For Crosspoint Switching Arrays, Yasser A. Abdel-Aziez

Theses

This thesis describes the fabrication of micron-sized vertical mirrors at the end of horizontal cantilevers, that are electrostatically controlled. The mirrors, 40x 40 μm with thicknesses of 1.5-6 μm, were made by using the etch resistance to 40% KOH etchant of <111> planes and oxide stripes. The cantilever beams, 100 to 350 μm long and 0.44 to 0.81 μm thick, were fabricated using the etch resistance of heavily doped boron layers to 10% KOH at 50 °C. Two technologies to introduce the boron layers were investigated. The ion implantation approach was based on thick oxide/photoresist masking. A maximum doping of 2.5 …

An On-Line Approach For Evaluating Trigonometric Functions, Rajesh Amin

Theses

This thesis investigates the evaluation of trigonometric functions based on an on-line arithmetic approach. On-line algorithms have been developed to evaluate the sine and cosine functions. Error analysis and heuristics are carried out to arrive at a minimal error algorithm based on the series expansion of the sine and cosine function.

A logical design based on the algorithm is presented where the unit is designed as a set of basic modules. A detailed bit slice design of each module is also presented. A simulator was designed as an experimental tool for synthesis of the on-line algorithms, and a tool for …

A Hybrid Low Bit-Rate Video Codec Using Subbands And Statistical Modeling, Ferhat Cakrak

Theses

A hybrid low bit-rate video codes using subbands and statistical modeling is proposed in this thesis. The redundancy within adjacent video frames is exploited by motion estimation and compensation. The Motion Compensated Frame Difference (MCFD) signals are decomposed into 7 subbands using 2-D dyadic tree structure and separable filters. Some of the subband signals are statistically modeled by using the 2-D AR(1) technique. The model parameters provide a representation of these subbands at the receiver side with a. certain level of error. The remaining subbands are compressed employing a classical waveform coding technique, namely vector quantization (VQ).

It is shown …

Coordination Of Time-Overcurrent Relays For High-Speed Power Line Protection, Nicos Charalambous

Theses

A properly coordinated protection system is essential to ensure that an electricity distribution network can operate within its requirements, regarding the safety of a power system. Automatic operation is necessary to isolate faults on a power system in a minimum time. The study of time coordination of relays suggests improved ways of power line protection. The protection must be sensitive enough to operate when a fault occurs under minimum fault conditions, yet be stable enough not to operate when its associated equipment is carrying the maximum rated current, which may be a short-time value. A power system is used as …

A Graphical Tool For Timed Petri Nets Using Object Oriented Programming, Baopu Liu

Theses

The objective of this effort is to develop a computer tool for drawing, editing and simulating Timed Petri Nets using object oriented programming. The developed C++ based Timed Petri Net Simulation Tool, TimedPNT, is capable of simulating discrete systems with both deterministic and stochastic delays. Preselection is used for conflict resolution. Performance and utilization results are automatically collected. XView™ Toolkit is used for building the TimedPNT's interactive graphical interface in compliance with AT&T's OPENLOOK® standard on a SunSparc™ IPX running SunOSTM 4.1.2. Compliance with the X Window standard makes the developed tool portable to other X Window based systems.

Performance Of National Research And Education Network While Transmitting Healthcare Information Data, Bhavesh Mahendra Shukla

Theses

National Research and Education Network(NREN) is a first step in the process of building a National Information Infrastructure(NII). NII will ultimately lead to Broadband Integrated Services Digital Network(B-ISDN), a network which will support global exchange of voice, data, images and video.

NREN will evolve out of present National Science Foundation Network (NSFNET), also known as Interim NREN. At present NSFNET operates at 45 MBits/sec. By 1996, there are plans to boost the data rate to 155 MBits/sec and to 620 MBits/sec by the turn of century.

In this thesis, present actual NSFNET is simulated using software simulation tool Networkll.5. The …

Measurement Of Heart Rate Variability Using Correlation Dimension And Entropy, Su Zhang

Theses

Heart rate variability regulation is controlled by the autonomic nervous system. Disorders of the autonomic nervous system may cause the loss of heart rate variability. Two new approaches, correlation dimension and entropy, based on ideas from nonlinear dynamics, have been applied to studying heart rate variability. The correlation dimension measures the extent of correlation between the data points. The entropy measures the amount of information needed to specify the state of a system. The interbeat interval signal (1BI) from eighteen subjects (nine normal controls and nine patients with Chronic Fatigue Syndrome (CFS) ) have been analyzed and compared. The results …

Adaptive Notch Filter, Yuchen Huang

Dissertations and Theses

The thesis presents a new adaptive notch filter (ANF) algorithm that is more accurate and efficient and has a faster convergent rate than previous ANF algorithms. In 1985, Nehorai designed an infinite impulse response (UR) ANF algorithm that has many advantages over previous ANF algorithms. It requires a minimal number of parameters with constrained poles and zeros. It has higher stability and sharper notches than any ANF algorithm until now. Because of the special filter structure and the recursive prediction error (RPE) method, however, the algorithm is very sensitive to the initial estimate of the filter coefficient and its covariance. …

Polarimetric Fiber Optic Weigh-In-Motion Sensor, Jieping Wang

Theses

During the past decade, the demand for new methods of measuring the weight of moving vehicles has grown substantially. In the 1980's, several techniques for weighing vehicles in motion were developed. However, they often suffer from high installation and maintenance costs as well as low accuracy. This thesis describes a new technique based on polarization preserving optical fibers. A fibercore HB600 Bow-Tie fiber with an initial beat length of 1.16 mm was employed in the present study. Sensor response is discussed in terms of the effects of force amplitudes and velocities on the calibration parameter T_f. T_{f …}

Information Processing Using Laser Speckle, Rathnakar Gopisetty

Masters Theses

"The random speckle intensity pattern, which is produced by the scattered optical field from a rough surface when illuminated, can be used as a carrier of information. A theoretical study is performed to use the speckle patterns for retrieving the information of various kinds of object motions. A mathematical model of speckle is developed and used to relate different speckle patterns at various intervals as the object is experiencing motion. Four different object motions, i.e., one dimensional perpendicular motion, axial motion, three-dimensional motion, and rotational motion of an object are analyzed. In each case an interference pattern is produced which …

Color Image Enhancement Using Both Chromatic And Luminance Components, George Eric Hague Ii

Retrospective Theses and Dissertations

A vast amount of work has been published regarding grayscale processing of digital images. Although some of this work has been adapted for color images, many of the resulting algorithms neglect the correlation that exists between the individual RGB color components. Consequently, they introduce color artifacts. Attempts have been made to decouple the RGB components through color space transformations that isolate the luminance from the chromatic information. Color image enhancement is then considered a two step process, where the luminance and the chromatic components are processed independently. However, the RGB color space only has a finite number of available colors, …

Synthesis Of Numerical Integrators For The Real-Time Digital Simulation Of Continuous Systems, Michael James Panzitta

Retrospective Theses and Dissertations

Real-time digital simulation is a powerful means for engineers and scientists in government, industry, and academia to perform research and training as well as serving as a basis for many commercial applications. Due to the special constraints imposed by digitally simulating continuous systems in real time, however, many of these systems either require costly high-speed components or are unable to provide suitable performance characteristics using affordable computers.

This dissertation describes a new technique for the synthesis of numerical integrators specifically designed for the real-time digital simulation of continuous systems. This methodology is based upon the fact that the state derivatives …

An Efficient Method For Representing And Computing Transitive Closure Over Temporal Relations, Vincent J. Kovarik

Retrospective Theses and Dissertations

The need for temporal reasoning is found throughout the engineering disciplines. James Allen introduced a representation for temporal reasoning based upon the concept of intervals. This approach provides a rich set of temporal relations for reasoning over events and changes in state. The full temporal algebra is NP-complete however. The algorithm developed by Allen executes in 0(n³) time but only ensures consistency between any three intervals.

This research presents an approach to representing interval relations as a bit-encoded form which captures the relationships between the end-points of the intervals. A bit-algebra is then defined which provides an …

The Characteristics Of Motion And Time Study In Taiwan's Electronics Industry And Their Relationship To Business Size, Betty Chang

Dissertations and Theses @ UNI

This research was conducted to investigate the characteristics of motion and time study implementation in Taiwan's electronics industry, as perceived by industrial engineers, and the relationships of these perceptions to business sizes of the firms. The questionnaires were mailed to 252 industrial engineers in the general firms group. A total of 206 (81.75%) instruments were returned. The questionnaires were then mailed to another 15 industrial engineers in the highly productive firms group. All the instruments (100%) were returned from the highly productive firm group. Telephone interviews were later conducted with six selected highly productive electronics firms to investigate their successful …

Automation Of Formation Flight Control, Vincent P. Reyna

Theses and Dissertations

The research contained in this thesis explores the concepts of Automated Formation Flight Control documented in three previous AFIT theses. The generic formation analyzed consists of a Leader and Wingman, with the Wingman referencing its maneuvers off of Leader maneuvers. Specifically, planar formation flight control concerning only heading and velocity changes is considered. Next, the vertical separation constraint is relaxed to allow wing maneuvers outside of the flight plane of the lead in order to minimize the energy expended by the wing in a maneuver. Analysis of the two forms of formation flight control investigated in this thesis reveals the …

An Analysis Of The Payback Potential Of New Lighting Technology, James L. Cox

Masters Theses

Recent, energy saving improvements in lighting technology have been made involving the use of more efficient lamps, silver coated light reflectors, and electronic light ballasts. Research indicates that it is economically feasible to retrofit existing light fixtures to utilize the advantages of these developments. This process consists of the removal of all standard lamps and ballasts in each light fixture, the installation of a highly refined light reflector and the replacement of the existing lamps with brighter, more efficient ones. Standard magnetic ballasts are exchanged for more efficient electronic ballasts. Resulting is a light fixture that produces a comparable amount …

Investigation Of Cebus Traffic Across A Router, With And Without Acknowledgment, Wannakuwattawaduge Lalith Fernando

Theses

A power line and twisted pair implementation of the Consumer Electronic Bus(CEBus) has great potential toward inexpensive home automation. Since the introduction of the CEBus Standard, there has been increasing efforts on evaluating its performance. However, most of the work has been performed for unacknowledged networks. Pan[18] was able to implement an acknowledged network for PL CEBus. In this thesis, the acknowledgment process has been taken one step further. The effect of acknowledgment on a Power Line and Twisted Pair CEBus network interconnected by a router is studied. CEBus network performance parameters such as message and packet delays, message throughput, …

A Multi-Dimensional Model Of Passive Mesfets For Use In Non-Linear Microwave Signal Processing, Roger Dorval

Theses

A multi-dimensional model which accurately predicts device non-linearities over frequency and power has been developed for MESFETs used in a passive configuration in microwave signal processing applications.

Historically, MESFETs have been used in linear control applications as passive microwave switches and attenuators. More recently, MESFETs operated as passive elements have been employed as power-sensitive non-linear transfer function generators to produce limiters, phase shifters, and linearizers. These devices offer simplicity, high performance, and the opportunity for application in MMIC technology.

This thesis deals with a mapping of passive MESFET non-linear characteristics, and provides insight into the causes of non-linearity in MESFETs …

Logic Synthesis With High Testability For Cellular Arrays, Andisheh Sarabi

Dissertations and Theses

The new Field Programmable Gate Array (FPGA) technologies and their structures have opened up new approaches to logic design and synthesis. The main feature of an FPGA is an array of logic blocks surrounded by a programmable interconnection structure. Cellular FPGAs are a special class of FPGAs which are distinguished by their fine granularity and their emphasis on local cell interconnects. While these characteristics call for specialized synthesis tools, the availability of logic gates other than Boolean AND, OR and NOT in these architectures opens up new possibilities for synthesis. Among the possible realizations of Boolean functions, XOR logic is …