Theory and Algorithms Commons^™

Unidirectional Cordic For Efficient Computation Of Trigonometric And Hyperbolic Functions, Satish Ravichandran

Electrical & Computer Engineering Theses & Dissertations

CORDIC (Coordinate Rotation Digital Computer) is an iterative algorithm to compute values of trigonometric, logarithmic and transcendental functions by performing vector rotations, which can be implemented with only shift and add operations in a digital system. CORDIC algorithms are extensively used in the areas of digital signal processing, digital image processing and artificial neural networks. A new technique, named unidirectional CORDIC, for efficient computation of trigonometric and hyperbolic functions is presented in this thesis. In the conventional CORDIC algorithm, the vector rotations are performed in both clockwise and counterclockwise directions, but in the unidirectional CORDIC the vectors are rotated only …

Adaptive Parallel Framework Algorithm (Apfa) For Environmental Engineering Applications, Lianghua Zhou

Civil & Environmental Engineering Theses & Dissertations

This research proposes a new framework methodology for integrating environmental computer applications in flexible, open and adaptively and reusable manners so that the resulting application framework could be used to effectively, flexibly and rapidly handle various environmental problems and issues. Research also demonstrates the framework algorithm with a case study. The proposed algorithm is referred as Adaptive Parallel Framework Algorithm (APF A). Core concept of the APF A is based on a parallelism, "many-to-one" mode to communicate among environmental applications, and takes advantages of a loosely coupled technology that helps archiving the required flexibility, extensibility and usability of integrated systems. …

Fast And Space-Efficient Location Of Heavy Or Dense Segments In Run-Length Encoded Sequences, Ronald I. Greenberg

Computer Science: Faculty Publications and Other Works

This paper considers several variations of an optimization problem with potential applications in such areas as biomolecular sequence analysis and image processing. Given a sequence of items, each with a weight and a length, the goal is to find a subsequence of consecutive items of optimal value, where value is either total weight or total weight divided by total length. There may also be a specified lower and/or upper bound on the acceptable length of subsequences. This paper shows that all the variations of the problem are solvable in linear time and space even with non-uniform item lengths and divisible …

A New Message-Based Protocol For Building A Platform And Language Independent Distributed Object Model, Hazem S. El Ashmawi

Archived Theses and Dissertations

Standardization of messaging topologies for communication in recent distributed object computing architectures is becoming more and more inevitable. The emergence of a structured and flexible document model as XML has made an entry point towards this goal. In this thesis, we are utilizing the flexibility of XML and the simplicity of low -level socket communication to build a generalized messaging model that provides a basis for standardization and supports interoperability among existing distributed object computing architectures. The proposed system is composed of the basic components of a distributed architecture constituting a number of broker components acting as naming services and …

The Online Median Problem, Ramgopal R. Mettu, C. Greg Plaxton

Dartmouth Scholarship

We introduce a natural variant of the (metric uncapacitated) k-median problem that we call the online median problem. Whereas the k-median problem involves optimizing the simultaneous placement of k facilities, the online median problem imposes the following additional constraints: the facilities are placed one at a time, a facility cannot be moved once it is placed, and the total number of facilities to be placed, k, is not known in advance. The objective of an online median algorithm is to minimize the competitive ratio, that is, the worst-case ratio of the cost of an online placement to …

Automatic Speaker Identification Using Reusable And Retrainable Binary-Pair Partitioned Neural Networks, Ashutosh Mishra

Electrical & Computer Engineering Theses & Dissertations

This thesis presents an extension of the work previously done on speaker identification using Binary Pair Partitioned (BPP) neural networks. In the previous work, a separate network was used for each pair of speakers in the speaker population. Although the basic BPP approach did perform well and had a simple underlying algorithm, it had the obvious disadvantage of requiring an extremely large number of networks for speaker identification with large speaker populations. It also requires training of networks proportional to the square of the number of speakers under consideration, leading to a very large number of networks to be trained …

Explicit Building-Block Multiobjective Genetic Algorithms: Theory, Analysis, And Developing, Jesse B. Zydallis

Theses and Dissertations

This dissertation research emphasizes explicit Building Block (BB) based MO EAs performance and detailed symbolic representation. An explicit BB-based MOEA for solving constrained and real-world MOPs is developed the Multiobjective Messy Genetic Algorithm II (MOMGA-II) which is designed to validate symbolic BB concepts. The MOMGA-II demonstrates that explicit BB-based MOEAs provide insight into solving difficult MOPs that is generally not realized through the use of implicit BB-based MOEA approaches. This insight is necessary to increase the effectiveness of all MOEA approaches. In order to increase MOEA computational efficiency parallelization of MOEAs is addressed. Communications between processors in a parallel MOEA …

A Parallel Algorithm To Solve The Mathematical Problem "Double Coset Enumeration Of S₂₄ Over M₂₄", Elena Yavorska Harris

Theses Digitization Project

This thesis presents and evaluates a new parallel algorithm that computes all single cosets in the double coset M₂₄ P M₂₄, where P is a permutation on n points of a certain cycle structure, and M₂₄ is the Mathieu group related to a Steiner system S(5, 8, 24) as its automorphism group. The purpose of this work is not to replace the existing algorithms, but rather to explore a possibility to extend calculations of single cosets beyond the limits encountered when using currently available methods.

The Window Least Mean Square Error Algorithm, Anna Semenovna Degtyarena

Theses Digitization Project

In order to improve the performance of LMS (least mean square) algorithm by decreasing the amount of calculations this research proposes to make an update on each step only for those elements from the input data set, that fall within a small window W near the separating hyperplane surface. This work aims to describe in detail the results that can be achieved by using the proposed LMS with window learning algorithm in information systems that employ the methodology of neural network for the purposes of classification.

The Staging Transformation Approach To Mixing Initiative, Robert Capra, Michael Narayan, Saverio Perugini, Naren Ramakrishnan, Manuel A. Pérez-Quiñones

Computer Science Faculty Publications

Mixed-initiative interaction is an important facet of many conversational interfaces, flexible planning architectures, intelligent tutoring systems, and interactive information retrieval systems. Software systems for mixed-initiative interaction must enable us to both operationalize the mixing of initiative (i.e., support the creation of practical dialogs) and to reason in real-time about how a flexible mode of interaction can be supported (e.g., from a meta-dialog standpoint). In this paper, we present the staging transformation approach to mixing initiative, where a dialog script captures the structure of the dialog and dialog control processes are realized through generous use of program transformation techniques (e.g., partial …

Personalizing Interactions With Information Systems, Saverio Perugini, Naren Ramakrishnan

Computer Science Faculty Publications

Personalization constitutes the mechanisms and technologies necessary to customize information access to the end-user. It can be defined as the automatic adjustment of information content, structure, and presentation tailored to the individual. In this chapter, we study personalization from the viewpoint of personalizing interaction. The survey covers mechanisms for information-finding on the web, advanced information retrieval systems, dialog-based applications, and mobile access paradigms. Specific emphasis is placed on studying how users interact with an information system and how the system can encourage and foster interaction. This helps bring out the role of the personalization system as a facilitator which reconciles …

Ordering Genetic Algorithm Genomes With Reconstructability Analysis, Stephen Shervais, Martin Zwick

Complex Systems Faculty Publications and Presentations

The building block hypothesis implies that genetic algorithm effectiveness is influenced by the relative location of epistatic genes on the chromosome. We find that this influence exists, but depends on the generation in which it is measured. Early in the search process it may be more effective to have epistatic genes widely separated. Late in the search process, effectiveness is improved when they are close together. The early search effect is weak but still statistically significant; the late search effect is much stronger and plainly visible. We demonstrate both effects with a set of simple problems, and show that infonnation-theoretic …

Interpolation Techniques For Overset Grids, Paul S. Sherman, Nathan B. Edgar

Journal of the Arkansas Academy of Science

The use of finite difference schemes in computational aeroacoustics requires the use of structured grids incomputational space. Complex geometries in the physical space can be modeled using multiple overlapping grids that are transformed into computational space. In this work, finite difference schemes are used that necessitate the addition of psuedo- or ghost-points in the overlap region of the grids for closure of the difference stencil. The functional values at these ghost points must be approximated from the values at the original grid points. This paper investigates interpolation techniques for these overset grids. An n th order interpolation scheme using Lagrange …

Qr Factorization With Morton-Ordered Quadtree Matrices For Memory Re-Use And Parallelism, Jeremy D. Frens, David S. Wise

University Faculty Publications and Creative Works

Quadtree matrices using Morton-order storage provide natural blocking on every level of a memory hierarchy. Writing the natural recursive algorithms to take advantage of this blocking results in code that honors the memory hierarchy without the need for transforming the code. Furthermore, the divide-and-conquer algorithm breaks problems down into independent computations. These independent computations can be dispatched in parallel for straight-forward parallel processing. Proof-of-concept is given by an algorithm for QR factorization based on Givens rotations for quadtree matrices in Morton-order storage. The algorithms deliver positive results, competing with and even beating the LAPACK equivalent.

A Performance Analysis Of Distributed Algorithms In Javaspaces, Corba Services And Web Services, Suresh Sunku

UNF Graduate Theses and Dissertations

Implementation of distributed parallel algorithms on networked computers has always been very difficult until the introduction of service-oriented architectures (SOA) like JavaSpaces service, CORBA services and Web Services. Algorithms of the type Master/Worker pattern are implemented with relative ease using the SOAs. This project analyzes the performance of such algorithms on three contemporary SOAs namely JavaSpaces service, CORBA services and Web Services. These architectures make the implementations of distributed algorithms reasonably fault tolerant and highly and dynamically scalable. Also, the systems built on these architectures are generally loosely coupled and operate asynchronously.

In this project we measure and analyze the …

Active Processor Scheduling Using Evolution Algorithms, David J. Caswell

Theses and Dissertations

The allocation of processes to processors has long been of interest to engineers. The processor allocation problem considered here assigns multiple applications onto a computing system. With this algorithm researchers could more efficiently examine real-time sensor data like that used by United States Air Force digital signal processing efforts or real-time aerosol hazard detection as examined by the Department of Homeland Security. Different choices for the design of a load balancing algorithm are examined in both the problem and algorithm domains. Evolutionary algorithms are used to find near-optimal solutions. These algorithms incorporate multiobjective coevolutionary and parallel principles to create an …

Mining Of Correlated Rules In Genome Sequences, L. Lin, L. Wong, Tze-Yun Leong, P. S. Lai

Research Collection School Of Computing and Information Systems

With the huge amount of data collected by scientists in the molecular genetics community in recent years, there exists a need to develop some novel algorithms based on existing data mining techniques to discover useful information from genome databases. We propose an algorithm that integrates the statistical method, association rule mining, and classification rule mining in the discovery of allelic combinations of genes that are peculiar to certain phenotypes of diseased patients.

Yet Another Algorithm For Pitch Tracking (Yaapt), Kavita Kasi

Electrical & Computer Engineering Theses & Dissertations

This thesis presents a pitch detection algorithm that is extremely robust for both high quality and telephone speech. The kernel method for this algorithm is the Normalized Cross Correlation (NCCF) reported by David Talkin [16]. Major innovations include: processing of the original acoustic signal and a nonlinearly processed version of the signal to partially restore very weak F0 components; intelligent peak picking to select multiple F0 candidates and assign merit factors; and, incorporation of highly robust pitch contours obtained from smoothed versions of low frequency portions of spectrograms. Dynamic programming is used to find the ''best" pitch track among all …

Study Of Transport Properties Of Inas Using Monte Carlo Simulation, Satyanadh Gundimada

Electrical & Computer Engineering Theses & Dissertations

The present research is aimed at ascertaining the usefulness of InAs semiconductor material for single photon avalanche photo detectors operating in the Geiger mode at 2 μm wavelengths. InAs is considered as the material suitable for the purpose because of its less bandgap and lower effective mass of the electrons when compared to other semiconductor materials presently in use. Hence, theoretically transient transport properties of bulk InAs are superior and the velocity overshoot phenomena stronger. InAs is a relatively less explored material when compared to other materials like GaAs. The choice of the material is justified with thorough exploration of …

On The Area Of Hypercube Layouts, Ronald I. Greenberg, Lee Guan

Computer Science: Faculty Publications and Other Works

This paper precisely analyzes the wire density and required area in standard styles for the hypercube. It shows that the most natural, regular layout of a hypercube of N^2 nodes in the plane, in a NxN grid arrangement, uses floor(2N/3)+1 horizontal wiring tracks for each row of nodes. (In the process, we see that the number of tracks per row can be reduced by 1 with a less regular design, as can also be seen from an independent argument of Bezrukov et al.) This paper also gives a simple formula for the wire density at any cut position and a …

Warcraft Iii - Maps & Benchmark Problems, Nathan R. Sturtevant, Blizzard Corp.

Moving AI Lab: 2D Maps and Benchmark Problems

Maps extracted from Warcraft III from Blizzard Corp. for use and distribution as benchmark problems.

Contains 36 maps and benchmark problem sets, scaled to 512x512 and converted to a simple grid-based format.

Translation And Rotation Invariant Multiscale Image Registration, Jennifer L. Manfra

Theses and Dissertations

The most recent research involved registering images in the presence of translations and rotations using one iteration of the redundant discrete wavelet transform. We extend this work by creating a new multiscale transform to register two images with translation or rotation differences, independent of scale differences between the images. Our two-dimensional multiscale transform uses an innovative combination of lowpass filtering and the continuous wavelet transform to mimic the two-dimensional redundant discrete wavelet transform. This allows us to obtain multiple subbands at various scales while maintaining the desirable properties of the redundant discrete wavelet transform. Whereas the discrete wavelet transform produces …

Night Out Itinerary Creator, Jennifer Hood

Honors Capstone Projects and Theses

No abstract provided.

Modeling And Simulation Of Steady State And Transient Behaviors For Emergent Socs, Joann M. Paul, Arne Suppe, Donald E. Thomas

Research Collection School Of Computing and Information Systems

We introduce a formal basis for viewing computer systems as mixed steady state and non-steady state (transient) behaviors to motivate novel design strategies resulting from simultaneous consideration of function, scheduling and architecture. We relate three design styles: Hierarchical decomposition, static mapping and directed platform that have traditionally been separate. By considering them together, we reason that once a steady state system is mapped to an architecture, the unused processing and communication power may be viewed as a platform for a transient system, ultimately resulting in more effective design approaches that ease the static mapping problem while still allowing for effective …

Nonparametric Techniques To Extract Fuzzy Rules For Breast Cancer Diagnosis Problem, Manish Sarkar, Tze-Yun Leong

Research Collection School Of Computing and Information Systems

This paper addresses breast cancer diagnosis problem as a pattern classification problem. Specifically, the problem is studied using Wisconsin-Madison breast cancer data set. Fuzzy rules are generated from the input-output relationship so that the diagnosis becomes easier and transparent for both patients and physicians. For each class, at least one training pattern is chosen as the prototype, provided (a) the maximum membership of the training pattern is in the given class, and (b) among all the training patterns, the neighborhood of this training pattern has the least fuzzy-rough uncertainty in the given class. Using the fuzzy-rough uncertainty, a cluster is …

Real-Time Travel Time Estimation Using Macroscopic Traffic Flow Models, Pushkin Kachroo, Kaan Ozbay, Antoine G. Hobeika

Electrical & Computer Engineering Faculty Research

This paper presents the estimation of travel time on highways based on macroscopic modelling. The focus is on real-time values as compared to average or static values. The macroscopic models are used for distributed and time/space lumped settings and corresponding travel time estimation functions and algorithms are developed. The implications of these algorithms for the implementation of various incident management and traffic control strategies are also discussed.

Minimum Mean Square Error Spectral Peak Envelope Estimation For Automatic Vowel Classification, Jaishree Venugopal

Electrical & Computer Engineering Theses & Dissertations

Spectral feature computations continue to be a very difficult problem for accurate machine recognition of speech. In this work, which focuses on vowels, a new spectral peak envelope method for vowel classification is developed, based on a missing frequency components model of speech recognition. According to the missing frequency components model, vowel recognition depends only on the spectral (harmonic) peaks. Smoothing and interpolation of the spectra, performed in the standard cepstral analysis method commonly used in automatic speech recognition, actually loses valuable information and results in reduced recognition accuracy. The new method for feature extraction presented in this thesis is …

Approximation Techniques For Average Completion Time Scheduling, Chandra Chekuri, Rajeev Motwani, Balas Natarajan, Clifford Stein

Dartmouth Scholarship

We consider the problem of nonpreemptive scheduling to minimize average ( weighted) completion time, allowing for release dates, parallel machines, and precedence constraints. Recent work has led to constant-factor approximations for this problem based on solving a preemptive or linear programming relaxation and then using the solution to get an ordering on the jobs. We introduce several new techniques which generalize this basic paradigm. We use these ideas to obtain

improved approximation algorithms for one-machine scheduling to minimize average completion time with release dates. In the process, we obtain an optimal randomized on-line algorithm for the same problem that beats …

Genetic Algorithms For Communications Network Design - An Empirical Study Of The Factors That Influence Performance, Hsinghua Chou, G. Premkumar, Chao-Hsien Chu

Research Collection School Of Computing and Information Systems

We explore the use of GAs for solving a network optimization problem, the degree-constrained minimum spanning tree problem. We also examine the impact of encoding, crossover, and mutation on the performance of the GA. A specialized repair heuristic is used to improve performance. An experimental design with 48 cells and ten data points in each cell is used to examine the impact of two encoding methods, three crossover methods, two mutation methods, and four networks of varying node sizes. Two performance measures, solution quality and computation time, are used to evaluate the performance. The results obtained indicate that encoding has …

Traveling Salesman Problem For Surveillance Mission Using Particle Swarm Optimization, Barry R. Secrest

Theses and Dissertations

The surveillance mission requires aircraft to fly from a starting point through defended terrain to targets and return to a safe destination (usually the starting point). The process of selecting such a flight path is known as the Mission Route Planning (MRP) Problem and is a three-dimensional, multi-criteria (fuel expenditure, time required, risk taken, priority targeting, goals met, etc.) path search. Planning aircraft routes involves an elaborate search through numerous possibilities, which can severely task the resources of the system being used to compute the routes. Operational systems can take up to a day to arrive at a solution due …