Engineering Commons^™

Source Localization In A Time-Varying Ocean Waveguide, Cristiano Soares, Martin Siderius, Sérgio M. Jesus

Electrical and Computer Engineering Faculty Publications and Presentations

One of the most stringent impairments in matched-field processing is the impact of missing or erroneous environmental information on the final source location estimate. This problem is known in the literature as model mismatch and is strongly frequency dependent. Another unavoidable factor that contributes to model mismatch is the natural time and spatial variability of the ocean waveguide. As a consequence, most of the experimental results obtained to date focus on short source-receiver ranges (usually <5 >km), stationary sources, reduced time windows and frequencies generally below 600 Hz. This paper shows that MFP source localization can be made robust to time–space …

Range-Dependent Seabed Characterization By Inversion Of Acoustic Data From A Towed Receiver Array, Martin Siderius, Peter L. Nielsen, Peter Gerstoft

Electrical and Computer Engineering Faculty Publications and Presentations

The MAPEX2000 experiments were conducted in the Mediterranean Sea in March, 2000 to determine seabed properties using a towed acoustic source and receiver array. Towed systems are advantageous because they are easy to deploy from a ship and the moving platform offers the possibility for estimating spatially variable (range-dependent) seabed properties. In this paper, seabed parameters are determined using a matched-field geoacoustic inversion approach with measured, towed array data. Previous research has successfully applied matched-field geoacoustic inversion techniques to measured acoustic data. However, in nearly all cases the inverted data were collected on moored, vertical receiver arrays. Results here show …

Recurring Beams In Hollow Metal Waveguides: Paraxial Approximation, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

For optical and near-optical applications in electromagnetics, the directed propagation of waves in free space and in lenslike media is often in the Cartesian form of Gaussian or more general Hermite-sinusoidal-Gaussian beams. It has been shown that recurring (rather than continuing) forms of such beams are possible in the paraxial approximation for certain hollow metal waveguides, in which multiple reflections from the waveguide walls may occur. Limitations on this recurrence behavior implicit in use of the paraxial approximation are considered here, and estimates are obtained for the maximum propagation distance before the onset of significant distortion of the recurring beams.

Performance Analysis Of A Maximum-Likelihood Speckle Motion Estimator, Donald D. Duncan, Sean J. Kirkpatrick

Electrical and Computer Engineering Faculty Publications and Presentations

Presented herein is a performance analysis of a maximum likelihood estimator for calculating small speckle motions. Such estimators are important in a variety of speckle techniques used in non-destructive evaluation. The analysis characterizes the performance (bias and RMS deviation) of the estimator as a function of the signal-to-noise ratio. This SNR parameter is a convenient surrogate for decorrelation of sequential speckle patterns such as are seen in biological tissues. Although the particular estimator is predicated on speckle motions that are a small fraction of a pixel, accurate performance is demonstrated for instantaneous motions of up to ±0.8 pixel/record. Beyond this …

Logic Synthesis For Regular Layout Using Satisfiability, Marek Perkowski, Alan Mishchenko

Electrical and Computer Engineering Faculty Publications and Presentations

In this paper, we propose a regular layout geometry called 3×3 lattice. The main difference of this geometry compared to the known 2×2 regular layout geometry is that it allows the cofactors on a level to propagate to three rather than two nodes on the lower level. This gives additional freedom to synthesize compact functional representations. We propose a SAT-based algorithm, which exploits this freedom to synthesize 3×3 lattice representations of completely specified Boolean functions. The experimental results show that the algorithm generates compact layouts in reasonable time.

Evolving Quantum Circuits And An Fpga-Based Quantum Computing Emulator, Goran Negovetic, Marek Perkowski, Martin Lukac, Andrzej Buller

Electrical and Computer Engineering Faculty Publications and Presentations

The goal of the PQLG group is to develop complete methodologies, software tools and circuits for quantum logic. Our interests are mainly in logic synthesis for quantum circuits and quantum system design [10]. Emulation of quantum circuits using standard reconfigurable FPGA technology and FPGA-based Evolvable Quantum Hardware, proposed here, are research areas not yet dealt with by other research groups. A parallel software simulator was presented in [13].

Automated Synthesis Of Generalized Reversible Cascades Using Genetic Algorithms, Martin Lukac, Mikhail Pivtoraiko, Alan Mishchenko, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

We propose an automated synthesis of Reversible logic (RL) circuits using Darwinian and Lamarckian Genetic Algorithms (GA). Our designs are in a form of cascades of generalized gates which generalize factorized Exclusive-Or-Sum-of-Products (ESOP) circuits. GA can be used to explore the problem space of combinational functions and here it is used to evolve reversible logic circuits. We emphasize the role of problem encoding - a well-designed encoding leads to improved results. Our method with well-encoded circuits is compared to standard method on classical benchmarks in GA, and shows good results for synthesis of both random functions and benchmark functions with …

A New Approach To Robot’S Imitation Of Behaviors By Decomposition Of Multiple-Valued Relations, Uland Wong, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

Relation decomposition has been used for FPGA mapping, layout optimization, and data mining. Decision trees are very popular in data mining and robotics. We present relation decomposition as a new general-purpose machine learning method which generalizes the methods of inducing decision trees, decision diagrams and other structures. Relation decomposition can be used in robotics also in place of classical learning methods such as Reinforcement Learning or Artificial Neural Networks. This paper presents an approach to imitation learning based on decomposition. A Head/Hand robot learns simple behaviors using features extracted from computer vision, speech recognition and sensors.

Turing Day : 90Ème Anniversaire De La Naissance De Alan Mathison Turing, Christof Teuscher

Electrical and Computer Engineering Faculty Publications and Presentations

A brief statement on the life work and significance of computing pioneer Alan Turing, on the 90th anniversary of his birth.

Logic Synthesis Of Reversible Wave Cascades, Alan Mishchenko, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

A circuit is reversible if it maps each input vector into a unique output vector, and vice versa. Reversible circuits lead to power-efficient CMOS implementations. Reversible logic synthesis may be applicable to optical and quantum computing. Minimizing garbage bits is the main challenge in reversible logic synthesis. This paper introduces an algorithm to generate the cascade of reversible complex Maitra terms (called here reversible wave cascade) implementing incompletely specified Boolean functions. The remarkable property of the presented method compared to other reversible synthesis methods is that it creates at most one constant input and no additional garbage outputs. Preliminary estimation …

Le Bio Wall : Un Tissue Informatique Pour Le Prototypage De Systèmes Bio-Inspirés, Andre Stauffer, Daniel Mange, Gianluca Tempesti, Christof Teuscher

Electrical and Computer Engineering Faculty Publications and Presentations

Dans cet article, nous décrivons le BioWall, un tissu informatique reconfigurable géant développé dans le but d’y implémenter des machines mettant en oeuvre les principes de notre projet Embryonique. Bien que ses dimensions et ses caractéristiques en font d’abord un objet de démonstration publique, le BioWall constitue également un outil de recherche précieux, du fait que sa faculté de reprogrammation et sa structure cellulaire s’adaptent parfaitement à l’implémentation de toutes sortes de systèmes bioinspirés. Pour illustrer ces capacités, nous décrivons un ensemble d’applications qui reflètent différentes sources d’inspiration biologique allant des systèmes biologiques ontogénétiques aux dispositifs évolutifs phylogénétiques, en passant …

Forces On Permeable Conductors In Magnetic Fields, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

It is often implied that the force density formula dF/dV = JXB is all that is required to calculate the force that would be experienced by any stationary current-carrying medium in a region of space containing a magnetic field. However, representations of this formula are not all compatible, and the methods of applying such formulas when the conductor or surrounding medium have permeabilities different from vacuum are not widely known. The simplest case that one might consider is that of a current-carrying wire in an otherwise uniform field. It appears that the experimental measurements corresponding to such a situation have …

Efficient Algorithms For Creation Of Linearly-Independent Decision Diagrams And Their Mapping To Regular Layouts, Marek Perkowski, Bogdan Jaroslaw Falkowski, Malgorzata Chrzanowska-Jeske, Rolf Dreschler

Electrical and Computer Engineering Faculty Publications and Presentations

A new kind of a decision diagrams are presented: its nodes correspond to all types of nonsingular expansions for groups of input variables, in particular pairs. The diagrams are called the Linearly Independent (LI) Decision Diagrams (LI DDs). There are 840 nonsigular expansions for a pair of variables, thus 840 different types of nodes in the tree. Therefore, the number of nodes in such (exact) diagrams is usually much smaller than the number of nodes in the well-known Kronecker diagrams (which have only single-variable Shannon, Positive Davio, and Negative Davio expansions in nodes). It is usually much smaller than 1/3 …

Generalized Inclusive Forms — New Canonical Reed-Muller Forms Including Minimum Esops, Marek Perkowski, Alan Mishchenko, Malgorzata Chzanowka-Jeske

Electrical and Computer Engineering Faculty Publications and Presentations

Reed-Muller (AND/EXOR) expansions play an important role in logic synthesis and circuit design by producing economical and highly-testable implementations of Boolean functions [3–6]. The range of Reed-Muller expansions include canonical forms, i.e. expansions that create unique representations of a Boolean function. Several large families of canonical forms: fixed polarity Reed-Muller forms (FPRMs), generalized Reed-Muller forms (GRMs), Kronecker forms (KROs), and pseudo- Kronecker forms (PKROs), referred to as the Green/Sasao hierarchy, have been described [7–9]. (See Fig. 1 for a settheoretic relationship between these families.)

Term Trees In Application To An Effective And Efficient Atpg For And–Exor And And–Or Circuits, Lech Jozwiak, Aleksander Ślusarczyk, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

A compact data representation, in which the typically required operations are performed rapidly, and effective and efficient algorithms that work on these representations are the essential elements of a successful CAD tool. The objective of this paper is to present a new data representation—term trees (TTs)—and to discuss its application for an effective and efficient structural automatic test-pattern generation (ATPG). Term trees are decision diagrams similar to BDDs that are particularly suitable for structure representation of AND–OR and AND–EXOR circuits. In the paper, a flexible algorithm for minimum term-tree construction is discussed and an effective and efficient algorithm for ATPG …

Multiple-Valued Quantum Logic Synthesis, Marek Perkowski, Anas Al-Rabadi, Pawel Kerttopf

Electrical and Computer Engineering Faculty Publications and Presentations

This paper asks the question: is logic synthesis for quantum computers a practical research subject?

We would like to assume that any two quantum wires can interact, but we are limited by the realization constraints. Structure of atomic bonds in the molecule determines neighborhoods in the circuit. This is similar to restricted routing in FPGA layout - link between logic and layout synthesis known from CMOS design now appears in quantum. Below we are interested only in the so-called “permutation circuits” - their unitary quantum matrices are permutation matrices.