Electrical and Computer Engineering Commons^™

Video Compression Using Wavelets And Hierarchical Motion Estimation, Andrew Peter Byrne

Theses : Honours

This thesis investigates the benefits and the significant compression that can be obtained from data that has been decomposed using a wavelet transform. A video compression algorithm was developed that employs the wavelet transform and a hierarchical motion estimation algorithm which itself utilises benefits of the wavelet transform. Using MATLAB, a popular software tool for matrix based computation and analysis, several functions were developed which together formed the video compression algorithm. A variety of tests were conducted on a sample video sequence to ascertain the strengths and weaknesses of the techniques employed. The results, although not the same as the …

Study Of Dynamics And Mechanism Of Metal-Induced Silicon Growth, Elena A. Guliants, Wayne A. Anderson

Electrical and Computer Engineering Faculty Publications

The present study addresses the mechanism of metal-induced growth of device-quality silicon thin films. Si deposition was performed by magnetron sputtering on a 25-nm-thick Ni prelayer at 525–625 °C and yielded a continuous, highly crystalline film with a columnar structure. A Ni disilicide intermediate layer formed as a result of the Ni reaction with Si deposit provides a sufficient site for the Si epitaxial growth because lattice mismatch is small between the two materials. The reaction between Ni and Si was observed to progress in several stages. The NixSiy phase evolution in a Ni:Si layer was studied by x-ray photoelectron …

Resonant Energy Transfer From Argon Dimers To Atomic Oxygen In Microhollow Cathode Discharges, M. Moselhy, R. H. Stark, K. H. Schoenbach, U. Kogelschatz

Bioelectrics Publications

The emission of atomic oxygen lines at 130.2 and 130.5 nm from a microhollow cathode discharge in argon with oxygen added indicates resonant energy transfer from argon dimers to oxygen atoms. The internal efficiency of the vacuum-ultraviolet (VUV) radiation was measured as 0.7% for a discharge in 1100 Torr argon with 0.1% oxygen added. The direct current VUV point source operates at voltages below 300 V and at current levels of milliamperes.

Self-Consistent Simulations Of Electroporation Dynamics In Biological Cells Subjected To Ultrashort Electrical Pulses, R. P. Joshi, Q. Hu, R. Aly, K. H. Schoenbach, H. P. Hjalmarson

Bioelectrics Publications

The temporal dynamics of electroporation of cells subjected to ultrashort voltage pulses are studied based on a coupled scheme involving the Laplace, Nernst-Plank, and Smoluchowski equations. A pore radius dependent energy barrier for ionic transport, accounts for cellular variations. It is shown that a finite time delay exists in pore formation, and leads to a transient overshoot of the transmembrane potential V_mem beyond 1.0 V. Pore resealing is shown to consist of an initial fast process, a 10⁻⁴s delay, followed by a much slower closing at a time constant of about 10 ⁻¹s. This establishes a …

Comparison Of Two B-Polynomial Methods: Application To The Identification Of Time Delayed Processes, Ruiyao Gao, Aidan O'Dwyer

Conference papers

An extensive literature exists on the estimation of the model parameters of time delayed processes. The objective of this paper is to review the main B-polynomial approaches to the delay estimation problem. More specifically, two algorithms are discussed and compared theoretically and in simulation. The algorithms involve various procedures to assess how the model relates to the observed data, to a priori knowledge, and to the algorithms’ intended use. Simulation results indicate that both the algorithms can suitably identify the model parameters, including the time delay. This paper also discusses advantages and disadvantages of the methods and gives some guidelines …

Meta-Genetic Programming: Co-Evolving The Operators Of Variation, Bruce Edmonds

Turkish Journal of Electrical Engineering and Computer Sciences

The standard Genetic Programming approach is augmented by co-evolving the genetic operators. To do this the operators are coded as trees of indefinite length. In order for this technique to work, the language that the operators are defined in must be such that it preserves the variation in the base population. This technique can varied by adding further populations of operators and changing which populations act as operators for others, including itself, thus to provide a framework for a whole set of augmented GP techniques. The technique is tested on the parity problem. The pros and cons of the technique …

All-Optical Networking, Altan Koçyi̇ği̇t, Demeter Gökişik, Semi̇h Bi̇lgen

Turkish Journal of Electrical Engineering and Computer Sciences

A survey of recent literature on all optical networking is presented. Starting from multiplexing techniques and topological features, network design and performance issues are reviewed. Particular attention is devoted to Wavelength Division Multiplexing (WDM) networks. Static and dynamic solutions of the routing and wavelength assignment (RWA) problem are considered. Issues of current research are summarized.

An Efficient Indirect Branch Predictor, Yul Chu, M. R. Ito

Electrical and Computer Engineering Faculty Publications

In this paper, we present a new hybrid branch predictor called the GoStay2, which can effectively reduce indirect misprediction rates. The GoStay2 has two different mechanisms compared to other 2- stage hybrid predictors that use a Branch Target Buffer (BTB) as the first stage predictor: Firstly, to reduce conflict misses in the first stage, a new effective 2-way cache scheme is used instead of a 4-way setassociative. Secondly, to reduce mispredictions caused by an inefficient predict and update rule, a new selection mechanism and update rule are proposed. We have developed a simulation program by using Shade and Spixtools, provided …

An Integrated Design-Object Modeling Environment -- Pluggable Metamodel Mechanism --, Masaharu Yoshioka, Takayuki Sekiya, Tetsuo Tomiyama

Turkish Journal of Electrical Engineering and Computer Sciences

We propose a new integrated computational environment to support design object modeling, during engineering design process that requires a variety of design object models, such as a geometric model, a control model, and a finite element model. To integrate multiple design object models, we have developed a mechanism called a metamodel mechanism that maintains consistency among various models. The metamodel mechanism represents relationships among concepts used in these models and is useful, for example, to conduct concurrent engineering practices. In this framework, we formalize a design process as operations to the metamodel. This paper expands the concept of the metamodel …

Accurate Parameter Estimation For An Articulatory Speech Synthesizer With An Improved Neural Network Mapping, Hali̇s Altun, Tankut Yalçinöz, K. Mervyn Curtis

Turkish Journal of Electrical Engineering and Computer Sciences

Neural network (NN) applications have recently been employed to extract the parameters of an articulatory speech synthesizer from a given speech signal. Results from these attempts showed that a single NN is insufficient to cover all of the possible configurations uniquely. Moreover, apart from their computational advantages, NN mapping is so far not superior to the other mapping techniques [1]. Thus there is a clear need to improve NN solution to the inverse problem. Results from our earlier experiments with an articulatory speech synthesizer have shown that the statistical characteristic of the articulatory target pattern vectors can be exploited for …

Combining Multiple Representations For Pen-Based Handwritten Digit Recognition, Fevzi̇ Ali̇moğlu, Ethem Alpaydin

Turkish Journal of Electrical Engineering and Computer Sciences

We investigate techniques to combine multiple representations of a handwritten digit to increase classification accuracy without significantly increasing system complexity or recognition time. In pen-based recognition, the input is the dynamic movement of the pentip over the pressure sensitive tablet. There is also the image formed as a result of this movement. On a real-world database of handwritten digits containing more than 11,000 handwritten digits, we notice that the two multi-layer perceptron (MLP) based classifiers using these representations make errors on different patterns implying that a suitable combination of the two would lead to higher accuracy. We implement and compare …

Fuzzy Modeling Approach For Integrated Assessments Using Cultural Theory, Adnan Yazici, Fred E. Petry, Curt Pendergraft

Turkish Journal of Electrical Engineering and Computer Sciences

It has already been noted that the accurate prediction of societal responses requires the use of a formal model based on some social or cultural taxonomy. One such taxonomic candidate is Cultural Theory (CT). CT argues that all societies, irrespective of time or place, are informed by their underlying worldviews, which must be more or less Hierarchic, more or less Individualistic, more or less Egalitarian, and more or less Fatalistic. This approach appears to have a potential for cross-temporal and spatial comparisons that makes it a particularly attractive instrument for a study of the human dimensions of global climate change. …

Advances In Computer And Information Sciences: From Abacus To Holonic Agents, Tuncer Ören

Turkish Journal of Electrical Engineering and Computer Sciences

The shift of paradigm emphasizing the importance of the ability to process knowledge rather then being knowledgeable is stressed. A taxonomy of knowledge processing tools, machines, or systems is offered. Major possibilities for future achievements that the author would like to underline are listed with emphasis on agent technology, agent-directed simulation, holonic agents, holonic-agent simulation, and contribution of system theories for cognitive abilities such as understanding, learning, adaptation, and anticipation in computerization.

Bag Distributed Real-Time Operating System And Task Migration, Beki̇r Tevfi̇k Akgün

Turkish Journal of Electrical Engineering and Computer Sciences

BAG is a distributed operating system designed for real-time applications which is run on a distributed real-time system. The heterogeneously distributed BAG system consists of nodes which have VME-bus chassis, different types of processor modules, and an interconnection network. The operating system has three main parts having distributed properties: task migration, load balancing and a distributed file system. Heterogeneous task migration is based on the extended finite state machine (EFSM) programming model. The EFMS model has also eased the implementation of the migration mechanism. The load balancing algorithm is centralized in one node. But the overall system will be a …

Avalanche And Bit Independence Properties For The Ensembles Of Randomly Chosen N \Times N S-Boxes, Işil Vergi̇li̇, Melek D. Yücel

Turkish Journal of Electrical Engineering and Computer Sciences

Cryptographic test methods such as avalanche, strict avalanche and bit independence criteria, which measure the degree of security of the s-boxes of substitution-permutation networks, are applied to randomly generated ensembles of ( n \times n \) s-boxes. Statistical analysis of experimental data directs the work towards defining ``relative errors'' and examining the avalanche and strict avalanche criteria within ``relative error ranges''. Histograms of relative errors in each ensemble are evaluated, and combining the results of different ensembles corresponding to different values of the s-box size, variations of maximum relative errors versus the size of the s-box are depicted. Some predictions …

Performance Evaluation Of Safer K-64 And S-Boxes Of The Safer Family, Ekrem Aras, Melek D. Yücel

Turkish Journal of Electrical Engineering and Computer Sciences

If the characteristics of s-boxes of the SAFER family of ciphers are examined for the criteria of strict avalanche, bit independence, and XOR table distribution, experiments show that the ``exponentiating'' s-box has a weakness for an input difference of 128 (=10000000_{2}) and the ``logarithm-taking'' s-box has a weakness for an input difference of 253 (=11111101_{2}). However, since these experiments are performed by isolating the s-boxes from the general structure, they do not necessarily indicate a weakness in the overall algorithm. We propose a quick and rough test method, called the avalanche weight distribution criterion, to evaluate the overall performance of …

A More Efficient Design And Implementation Of Cal Programs In Natural Science Using Object-Oriented Technology, Jurgen Friedrich

Turkish Journal of Electrical Engineering and Computer Sciences

With the amount and complexity of science topics and applications increasing, the need for appropriate and effective science education is constantly growing. Computer-based education is very promising to help both teachers and learners in their difficult task, which involves complex psychological processes. This complexity is reflected in high demands on the design and implementation methods used to create computer-assisted learning (CAL) programs. Due to their concepts, flexibility, maintainability and extended library resources, object-oriented technology (OOT) is very suitable to producing this type of pedagogical tool. The introduced approach is demonstrated by a basketball simulation program for instruction in Newtonian mechanics …

Ota-C Based Proportional-Integral-Derivative (Pid) Controller And Calculating Optimum Parameter Tolerances, Cevat Erdal, Ali̇ Toker, Cevdet Acar

Turkish Journal of Electrical Engineering and Computer Sciences

Proportional-integral-derivative (PID) controllers are one of the most important control elements used in the process control industry. In practice, operational amplifiers are generally used in analog controllers. On the other hand, the operational transconductance amplifiers recently developed, which have some positive properties compared to operational amplifiers, are not used in analog controller design at present. Furthermore, the optimum parameter tolerances for the proposed PID circuit by the use of parameter sensitivities are determined. These tolerances keep the relative error at the output of the controller due to parameter variations in the tolerance region.

Scalar Wave Diffraction By A Perfectly Soft Infinitely Thin Circular Ring, Fati̇h Di̇kmen, Ertuğrul Karaçuha, Yury Alexanderovich Tuchkin

Turkish Journal of Electrical Engineering and Computer Sciences

A new strong mathematically rigorous and numerically effective method for solving the boundary value problem of scalar (for example acoustic) wave diffraction by a perfectly soft (Dirichlet boundary condition) infinitely thin circular ring is proposed. The method is based on the combination of the Orthogonal Polynomials Approach, and on the ideas of the methods of analytical regularization. As a result of the suggested regularization procedure, the initial boundary value problem is equivalently reduced to the infinite system of the linear algebraic equations of the second kind, i.e., to an equation of the type ( (I + H) x = b …

An Efficient Instruction Cache Scheme For Object-Oriented Languages, Yul Chu, M. R. Ito

Electrical and Computer Engineering Faculty Publications

We present an efficient cache scheme, which can considerably reduce instruction cache misses caused by procedure call/returns. This scheme employs N-way banks and XOR mapping functions. The main function of this scheme is to place a group of instructions separated by a call instruction into a bank according to the initial and final bank selection mechanisms. After the initial bank selection mechanism selects a bank on an instruction cache miss, the final bank selection mechanism will determine the final bank for updating a cache line as a correction mechanism. These two mechanisms can guarantee that recent groups of instructions exist …

Time-Domain Electric-Field Integral Equation With Central Finite Difference, Baek Ho Jung, Tapan Kumar Sarkar

Electrical Engineering and Computer Science - All Scholarship

In this paper, we present a new formulation using the time-domain electric-field integral equation (TD-EFIE) to obtain a transient scattering response from arbitrarily shaped conducting bodies. The time derivative of the magnetic vector potential is approximated with a central finite difference, and the scalar potential is time averaged by dividing it into two terms. This approach with an implicit method using central-difference results in accurate and stable transient scattering responses from conducting objects. Detailed mathematical steps are included, and several numerical results are presented.

The Problem Of A Viscoelastic Cylinder Rolling On A Rigid Half-Space, John Murrough Golden, G.A.C. Graham

Articles

The problem of a viscoelastic cylinder rolling on a rigid base, propelled by a line force acting at its centre, is solved in the noninertial approximation. The method used is based on a decomposition of hereditary integrals developed by the authors in previous work, and on the viscoelastic Kolosov-Muskhelishvili equations which are used to generate a Hilbert problem. In this formulation, the problem reduces to a nonsingular integral equation in space and time, which simplifies under steady-state conditions and for exponential decay materials, to algebraic form. There are also two subsidiary conditions.

In the case of a standard linear model, …

Measurement And Monitoring Of Microwave Reflection And Transmission Properties Of Cement-Based Materials For Propagation Modeling, Sergey Kharkovsky, U. C. Hasar, M. F. Akay, C. D. Atis

Electrical and Computer Engineering Faculty Research & Creative Works

A non-destructive, contactless, free-space method is used for measuring and monitoring the properties of cement-based materials. We analyse the propagation factor, penetration depth and reflection and transmission coefficients of the plane wave interacting with the highly lossy specimen. Results are presented of the measurement and monitoring of the properties of cement-based materials during all stages of their lives and different curing conditions The expected applications of the results for propagation modelling are discussed.

Robust Control Of Input Limited Smart Structural Systems, Sridhar Sana, Vittal S. Rao

Electrical and Computer Engineering Faculty Research & Creative Works

Integration of controllers with smart structural systems require the controllers to consume less power and to be small in hardware size. These requirements pose as limits on the control input and the order of the controllers. Use of reduced order model of the plant in the controller design can cause spill over problems in the closed-loop system due to possible excitation of the unmodeled dynamics. In this paper, we present a method to design output feedback robust controllers for smart structures in the presence of control input limits considering unmodeled dynamics as additive uncertainty in the design. The performance requirements …

Factory Automation: A Controls Course For Every University, Kelvin T. Erickson

Electrical and Computer Engineering Faculty Research & Creative Works

The majority of new control engineering positions is now in manufacturing and involves programmable logic controllers (PLCs). The paper describes two courses developed at the University of Missouri-Rolla to satisfy this demand. Both courses present the subject of programming PLCs with an emphasis on the design of the programs. Both courses contain an integral laboratory component that solidifies the concepts presented in the lectures. The philosophy and pedagogical features of the two courses are first described, followed by the structure of the lecture and the laboratory exercises.

Analysis Of A Four-Level Dc/Dc Buck Converter, Keith Corzine, J. Yuen, J. R. Baker

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a four-level DC/DC buck converter is introduced. The primary application for this converter is to regulate the center capacitor voltage in a four-level inverter system. The steady-state and average-value models for the proposed converter are developed and compared in simulation. The converter was constructed in the laboratory and verified on a four-level motor drive system. It was shown that the four-level DC/DC converter provides capacitor voltage balancing and allows higher output voltage utilization from the inverter.

A Continually Online Trained Neurocontroller For Excitation And Turbine Control Of A Turbogenerator, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

A Statistical Solution To A Text Decoding Challenge Problem, Xindi Cai, Rui Xu, Donald C. Wunsch, V. A. Samaranayake

Electrical and Computer Engineering Faculty Research & Creative Works

Given an encoded unknown text message in the form of a three dimensional spatial series generated by the use of four smooth nonlinear functions, we use a method based on simple statistical reasoning to pick up samples for rebuilding the four functions. The estimated functions are then used to decode the sequence. The experimental results show that our method gives a nearly perfect decoding, enabling us to submit a 100% accurate solution to the IJCNN challenge problem

Challenge Problem Update: Peec And Mom Analysis Of A Pc Board With Long Wires Attached, H. Wang, Todd H. Hubing, Bruce Archambeault

Electrical and Computer Engineering Faculty Research & Creative Works

At the 2000 IEEE International Symposium on EMC, a paper was presented by Y. Ji et al. (paper appears in 2001 proceedings) that compared the application of PEEC and MOM techniques to the analysis of one of the EMC Society/Applied Computational Electromagnetics Society special challenge problems. Good agreement was obtained between the two codes at 2 out of the 3 measurement ports. At that time, no definite explanation was provided for the discrepancy at the third port. This paper shows that the problem was (at least partly) related to assumptions made about the signal source

Applying The Method Of Moments And The Partial Element Equivalent Circuit Modeling Techniques To A Special Challenge Problem Of A Pc Board With Long Wires Attached, Yun Ji, Bruce Archambeault, Todd H. Hubing

Electrical and Computer Engineering Faculty Research & Creative Works

This paper investigates a canonical printed circuit board (PCB) problem using both a method of moments (MoM) and a partial element equivalent circuit (PEEC) modeling technique. The problem consists of a PCB populated with three traces. One trace is a signal line and the other two are I/O lines that couple to the signal line and extend beyond the boundary of the board. Although the MoM code was a frequency domain code and the PEEC code was a time-domain code, good agreement was achieved in both the time-domain and the frequency-domain