Digital Commons Network^™

The Theory Of Bootstrapped Algorithms And Their Applications To Cross Polarization Interference Cancelation, Abdulkadir Dinc

Dissertations

Dual-polarized transmission has become an important method for frequency re-use, particularly in satellite and microwave radio communication. Nevertheless, cross-polarization interference, which is inherent to this method, may cause degradation in system performance.

Different canceler [sic] structures have been proposed to mitigate the effect of cross-polarization. Among these are the diagonalizer, the least mean square (LMS) canceler [sic] and the bootstrapped cancelers [sic]. Bootstrapped canceler [sic] schemes have been proposed and implemented in different applications, such as satellites, tactical communications, and quadrature amplitude madulation [sic] (QAM) dual polarized microwave radio. Nevertheless, no attempt was made in the past to quantify the …

Performance Analysis Of Symbol Timing Recovery Circuits Employed In Digital Communications Systems, Elisha Yegal Bar-Ness

Theses

An analytical approach is presented for the jitter performance of a timing recovery circuit consisting of a prefilter, a zero-memory nonlinear device, and a narrow band postfilter tuned to the pulse repetition frequency. Assuming first a squarer type of nonlinearity, analytical expressions for the rms jitter in the timing wave are obtained as a function of the pre and post filtering characteristics. These expressions are suitable for judging the case where the baseband signal is bandlimited. Also for some specific examples, the jitter performance of this kind of STR circuit is evaluated.

Secondly, a general type of nonlinerity is assumed, …

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 …

Task Scheduling For Fms Based On Genetic Algorithm, Hung-Yuan Li

Theses

A Flexible Manufacturing System (FMS) consisting of p automated guided vehicles (AGV's), m workstations and n tasks is studied. The main problem investigated in this thesis is to find an optimal or suboptimal task scheduling for p AGV's among m workstations to complete n tasks.

An efficient approach based on genetic algorithms has been designed and implemented to solve the problem of task scheduling for a FMS. Near-optimal, or even optimal, task scheduling is accomplished by genetic algorithms. Simulation results on the algorithm are also discussed.

A Parallelogram Four-Frame Model In 3-D Motion And Structure Recovery Using Unified Optical Flow Field Approach, Zhichun Lin

Theses

In this paper a new concept of the unified optical flow field (UOFF) for 3 D motion analysis from a stereo image sequence is implemented which is an extension of the temporal optical flow formulations developed by Horn and Schunck. A four frame model is established and a spatial optical flow is also introduced.

In order to alleviate the problem of the strict requirement of two identical sensors in common stereo imagery a new imaging system is presented in this paper that needs only one camera, two plane mirrors and two switches to generate a phase shifted binocular sequence of …

Simulation Of Voice And Data Integration, Urmila S. Patel

Theses

A simulation model of integrated voice and data is developed. The data packets are transmitted during voice inactivity (i.e. silence duration). A statistical model of voice (talkspurt) and silence duration is generated. inter-arrival time between data packets is modeled using geometrical distribution. The data traffic statistics is simulated for a given voice activity model and various data packet arrival rates. Four important results are obtained by performing this simulation: 1. Average data packet delay versus arrival rate. 2. The optimal ratio of data packet arrival rate to average data packet delay. 3. Probability of wait time for various data packet …

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 …

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 …

The Neural Network Based Control System For Dynamic Channel Allocation In Pcn Communications, Ching-Yao Huang

Theses

A neural network based control system (NNCS) is adopted in this paper to conduct the channel allocation task in the personal communication networks (PCN). Binary adaptive resonance theory (ART-1) that was modified for pattern matching and provided the corresponding responses is selected as the basic algorithm for the system. Digital portable radio technology can provide reliable access to high quality wireless service for many users. Low power transmission requirement and small cell size configuration that can support more users and diverse services than cellular radio system are the attractive attributes of PCN. Assigning multiple time slots to a user in …

Automatic Infrared And Visual Inspection Of Solder Joints On Pcbs, Jiang Huang

Theses

This thesis reports the research results of automatic inspection of solder joints on printed circuit boards (PCBs). The previous work on this regard has been advanced significantly in the following three aspects. With the application of some microlens and the principle of geometric optics solder joints of real size are inspected in this work instead of larger simulation solder joints in the previous work. A new set of features is formulated and used for infrared inspection. Consequently, better results have been achieved in this work.

Reasonably good results demonstrate the capability of infrared inspection of solder joints on PCBs. Once …

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 …

A Comparative Study Of Image Coding Techniques : Filter Banks Vs. Discrete Cosine Transform, Hosam Fawzi Mutlag

Theses

Subband coding of still image frames using Binomial PR-QMF has been presented in this thesis. Simulation results have shown that the performance of subband coding using a low complexity coder is practically the same as the performance of the industry standard (8 x 8) DCT based image coder.

A low bit rate adaptive video coding technique is also introduced in this thesis. The redundancy within adjacent video frames is exploited by motion compensated interframe prediction. The Motion Compensated Frame Difference (MCFD) signals are filtered by employing Binomial PR-QMF structure into four subbands. Then, the subbands are quantized using an efficient …

Analysis And Implementation Of A Navigation System Using Vanishing Points In A Generalized Environment, Rolf Schuster

Theses

The development of accurate sensors is of crucial importance in navigation of mobile autonomous robots. The following master's thesis analyzes the use of vanishing points for robot navigation. Parallel lines in the environment of the robot are used to compute vanishing points which serve as a reference for guiding a robot. To accomplish the navigation tasks, three subtasks are to be performed: detection of straight lines, computation of vanishing points, and robot navigation with vanishing points.

An edge detection algorithm is presented that combines Sobel and Laplacian of Gaussian operators. The algorithm preserves the precision of the Laplacian of Gaussian …

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 …

Parallel Implementation Of Spatial Domain Image Processing Algorithms On The Mesh Connected Computer Simulator, Adury Devi Prasad

Theses

The performance of conventional computers in image processing applications is known to be inadequate due to the enormous computational requirements. Almost all image processing applications can be implemented in parallel. This thesis is the parallel implementation of neighborhood averaging and edge detection by the Sobel and Laplacian operators on the Mesh Connected Computer Computer Simulator (MCCS), a package developed at NJIT to study the behavior of SIMD machines. Expressions for speedup, utilization and efficiency have been derived. Suggestions for further improvements that can be incorporated in MCCS and its instruction set have been made.

Connected Component Labelling On A Pair Of Parallel Systems, Imran Shahid

Theses

Hypercubes and meshes are of the most successful parallel processing structures and are widely used in image processing applications. The mesh is a natural multiprocessor architecture for image processing because an N x N image can be directly mapped onto a mesh of N x N PEs (processing elements), holding each PE responsible for one pixel, with neighboring PEs responsible for neighboring pixels. Thus, local operations can be performed on the image, or local image features can be detected in parallel, with each processor simultaneously accessing its neighbor and computing the appropriate function for its neighborhood. Meshes and several other …

Androx Implementation Of Nonlinear Filter, Keh-Chao Chu

Theses

Nonlinear filters, such as morphological operations, play an important role in image processing. Several software implementations of nonlinear filters are presented in this thesis. There may exist more than one method to implement a specific operation. The methods used in this thesis are chosen to be most suited for the machine used according to its structure. These most suited methods are also generally best for software implementations on other machines as well. The machine used here is the Androx image computing workstation.

Tisi2/N+/P Silicon Junction Formation By Ion Implantation Through Metal Technique, Ying Wu

Theses

Experimental analysis, modeling and simulation of the formation and electrical characterization of TiSi₂/n⁺/p-Si shallow junctions are presented here. The formation of shallow n⁺-p junction, by ion implantation of As⁺ through Ti films evaporated on p-Si substrates followed by Rapid Thermal Annealing ( RTA ) and conventional furnace annealing has been performed in these experiments. Structural techniques such as Secondary Ion Mass Spectroscopy ( SIMS ) and Rutherford Backscattering spectroscopy ( RBS ) experiments have been employed to characterize the devices, and RUMP simulator was used to analyze and interpret the RBS data. Current-voltage …

A Mouse-Driven Interface For Androx Ics-400, Chin-Tien Chen

Theses

A mouse-driven interface is extremely useful for software performing image processing tasks. This thesis describes an implementation of a mouse-driven interface for the Androx ICS-400 image processing board. The Androx board is housed in a Sun 4/330 running a UNIX-based operating system. The main goal of this interface is to provide a consistent and friendly user interface for image processing tasks and integrating the Sun window libraries with the Androx libraries. Various image processing tasks, such as gray scale and binary morphological operations, histogram, thresholding, filtering, spot, logical operations, arithmetic operations, zooming, scrolling, rank and image acquisition are implemented in …

Bad Data Identification In Power Systems, Shichun Zou

Theses

Two classes of bad data (BD) identification methods in power system state estimation are studied.

The first class is the perturbation method. In this method, the obtained measurements are perturbed a few times. Each time a state is obtained from which measurement corrections are calculated. The statistics of the corrections corresponding to a BD are different from those corresponding to a healthy data. The method uses those differences for identification purposes.

The effectiveness of different indicators is studied. These include the normalized residual, the weighted residual, and residuals incorporating the statistics of the corrections.

The success rate of using the …

Exploiting And/Or Parallelism In Prolog, Bankim Shah

Dissertations and Theses

Logic programming languages have generated increasing interest over the last few years. Logic programming languages like Prolog are being explored for different applications. Prolog is inherently parallel. Attempts are being made to utilize this inherent parallelism. There are two kinds of parallelism present in Prolog, OR parallelism and AND parallelism. OR parallelism is relatively easy to exploit while AND parallelism poses interesting issues. One of the main issues is dependencies between literals.

It is very important to use the AND parallelism available in the language structure as not exploiting it would result in a substantial loss of parallelism. Any system …

Investigation Of Threaded Code, K. E. Graves, Paul D. Stigall

Computer Science Technical Reports

The design, structure and performance of threaded code are examined through the development of a threaded. code classification system and the modification of the threaded code technique used by a Forth programming language implementation. The classification system distinguishes threaded code designs by three elements: the interpreter, the code structure and the reference method to routines. Threaded code designs from the literature are described using the new classification scheme. The threaded code techniques of variable depth indirect threaded code and token indirect token threaded code are examined in a Forth programming language system on an INMOS IMS T222 transputer. Their design …

Identity Authentication Based On Keystroke Latencies Using Neural Networks, Angela Lammers, Sharon Langenfeld

Opportunities for Undergraduate Research Experience Program (OURE)

Most computer security systems verify the identity of a user through objects in the user's possession such as keys or magnetic cards, or through knowledge the user has, such as a password or PIN number. There are, however, two other methods of user verification, which have as yet received little or no attention. There has been some work done on the third method, recognition of physiological patterns (such as finger prints, retinal patterns, or voice patterns), but this work has been limited and requires expensive hardware to implement. The final method of user verification is through actions such as signature …

Noise Generators For The Simulation Of Digital Communication Systems, Martina F. Schollmeyer, William H. Tranter

Electrical and Computer Engineering Faculty Research & Creative Works

The generation of random numbers, having uniform and Gaussian distributions, with application to the time-domain simulation of communication systems is considered. The specific goal is to identify appropriate noise generation algorithms for use in system simulations for the determination of the symbol error probability of a digital communication system. Several methods of generating both uniform and Gaussian random numbers are examined. The algorithms considered were taken from those discussed in recent literature that appeared most appropriate for our problem. The algorithms were programmed in FORTRAN for use on a PC with math-coprocessor. Tests to evaluate the statistical properties of the …

Q Improvement Of A 5.2 Ghz Te011 Cavity By Incorporating Y1Ba2Cu3O7-X, R. Joseph Leclear

Electrical & Computer Engineering Theses & Dissertations

Research is undertaken to apply high temperature superconducting material to improve the quality factor (Q) of a 5.2 GHz cylindrical resonant cavity. In particular, the approach is to electrophoretically deposit polycrystalline Y₁Ba₂Cu₃O_7-x (YBCO) on the conducting surface of the cavity cylinder. Spalling of the YBCO ceramic coating due to expansion and contraction of the cavity during sintering and testing is overcome by segmenting the cylinder. Results show that the Q of the cavity is increased over that of a copper cavity at temperatures below 60 K. At 20 K, improvement exceeds a factor …

Afit/Afosr Symposium On Applications Of Wavelets To Signal Processing, Volume Ii, Tutorial Notes, Gregory T. Warhola, Mark E. Oxley, Steven K. Rogers, Matthew Kabrisky, Bruce W. Suter

AFIT Documents

The Air Force Institute of Technology (AFIT) hosted the Symposium on Applications of Wavelets to Signal processing during 20-22 March 1991 at the AFIT Science and Research Center, Wright-Patterson AFB, OH. This was the first major academic meeting of its kind held at AFIT. The symposium was sponsored by the Air Force Office of Scientific Research (AFOSR), Bolling AFB, DC. It focused on applications of wavelets to problems in image and speech processing, communications, and graphics and opened with a one-day short course, 'A Tutorial on Wavelets.' The symposium was attended by more than 220 researchers worldwide. They represented 15 …

A Fully Coupled, Automated Formation Control System For Dissimilar Aircraft In Maneuvering Formation Flight, Paul R. Rohs

Theses and Dissertations

This study developed a fully automated formulation control system, capable of controlling a number of like or dissimilar aircraft in maneuvering formation flight. C-130 fixed wing aircraft and H-53 helicopters were modelled in various formulations and simulated through a mix of maneuvers. External formation guidance was assumed as a single data burst of nominal function guidance commands and separation distances for each wing aircraft in the formation. No communication was assumed between formation aircraft. Wing aircraft track lead aircraft maneuvering with an ideal on-board sensor, maneuvering to maintain relative position. It was determined that lead aircraft inputs must be attenuated …

Fault Tolerant Clos Network, Preet Mohan S. Ahluwalia

Theses

Multistage interconnection networks, or MINs, provide paths between functional modules in multiprocessor systems. The MINs are usually segmented into several stages. Each stage connects inputs to appropriate links of the next stage so that the cumulative effect of all the stages satisfies input-output connection requirements.

This thesis deals with a fault tolerant Clos network. The fault tolerance technique involves addition of extra switches per stage to compensate for any switch failure The reliability analysis of both ordinary and fault tolerant Clos networks is presented. The optimal number of extra switches required to get the best reliability results has been analyzed.

Multiresolution Techniques : Laplacian Pyramid Coding And Its Comparison With Subband Coding, Danmei Chang

Theses

The multiresolution pyramid and related structures have been developed as intermediate representations between the purely frequency domain and purely spatial domain. In this thesis. we discuss two important pyramid structures which are often used in multiresolution representation: Laplacian pyramid and subband coding.

Laplacian pyramid. a typical pyramid structure, is studied in detail. By means of software implementation. we obtain a comprehensive understanding of its features and applications in image representation and data compression. Several modifications of pyramid structure are used to compress the data dynamic range, reduce the computational complexity and improve performance. Performance of the conventional Laplacian pyramid and …

Tri-Color Led Display System Using Microcontroller, Costakis A. Constantinou

Theses

A seven-by-forty-eight tricolor LED display panel is designed and built around the 68HC11 MCU.

Four bilateral switching transistors (4066) are used in a Wien bridge configuration to drive each tri-color LED. With this circuitry one is able to drive the tricolor LED symmetrically. An alternative design that uses only two switching transistors is also offered.

A software program was developed to output on the display scrolling and fixed messages. Each message could be displayed in a different color (Red, Green and Yellow) and at a different speed (Slow, Fast, and Medium). The program also includes an editor with insertion and …