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Tyflos: A Wearable Navigation Prototype For Blind & Visually Impaired; Design, Modelling And Experimental Results, Dimitrios Dakopoulos Jan 2009

Tyflos: A Wearable Navigation Prototype For Blind & Visually Impaired; Design, Modelling And Experimental Results, Dimitrios Dakopoulos

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The need for assistive devices has, had and will have a large merit in many engineering research arenas. This dissertation deals with the design, modeling, implementation and experimentation of the navigation component of a wearable assistive system for blind and visually impaired people, called TYFLOS (ΤΥΦΛΟΣ) which is the Greek word for "Blind".

The current prototype consists of two mini cameras attached to a pair of conventional eye-glasses, a 2D tactile display vibration array) which consists of 16 vibrating elements arranged in a 4x4 manner, attached to an elastic vest worn on the user's abdomen, a portable computer, an ...


Extracting, Representing And Mining Semantic Metadata From Text: Facilitating Knowledge Discovery In Biomedicine, Cartic Ramakrishnan Jan 2008

Extracting, Representing And Mining Semantic Metadata From Text: Facilitating Knowledge Discovery In Biomedicine, Cartic Ramakrishnan

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The information access paradigm offered by most contemporary text information systems is a search-and-sift paradigm where users have to manually glean and aggregate relevant information from the large number of documents that are typically returned in response to keyword queries. Expecting the users to glean and aggregate information has lead to several inadequacies in these information systems. Owing to the size of many text databases, search-and-sift is a very tedious often requiring repeated keyword searches refining or generalizing queries terms. A more serious limitation arises from the lack of automated mechanisms to aggregate content across different documents to discover new ...


Two Dimensional Localization Of Passive Uhf Rfid Tags, Bhavik Contractor Jan 2008

Two Dimensional Localization Of Passive Uhf Rfid Tags, Bhavik Contractor

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The advent of GPS has redefined the need of a positioning system in today*#8217;s ubiquitous computing world. While GPS works satisfactorily and is quite a norm in an outdoor environment, it fails to work indoors due to the inherent complexity of an indoor environment. There is an ever increasing need to develop an indoor positioning system and a lot of research has been done to solve the problem of indoor localization. These solutions differ on the basis of cost, dependency on environment, line of sight requirements and so on.

Passive RFID (Radio Frequency Identification) tags pose an interesting ...


Transformation Of Object-Oriented Associations And Embedded References To Them, Sneha Swamy Jan 2008

Transformation Of Object-Oriented Associations And Embedded References To Them, Sneha Swamy

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AFIT Wide Spectrum Object Modeling Environment (AWSOME) automatically generates executable code by applying transforms to the formal specifications developed from the domain knowledge. AWSOME uses the specification language called as AFIT Wide Spectrum Language (AWL). All the transforms developed for AWSOME depend on and manipulate Abstract Syntax Trees (ASTs) created by parsing the formal specifications of a model. The main idea is to speed the process of creating error free code, to aid reusability of code and also to make the maintenance changes to be consistent and correct. The AWSOME metamodel contains the structural (object) model, the functional (operations) model ...


Algorithmic Techniques Employed In The Isolation Of Codon Usage Biases In Prokaryotic Genomes, Douglas W. Raiford Iii Jan 2008

Algorithmic Techniques Employed In The Isolation Of Codon Usage Biases In Prokaryotic Genomes, Douglas W. Raiford Iii

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While genomic sequencing projects are an abundant source of information for biological studies ranging from the molecular to the ecological in scale, much of the information present may yet be hidden from casual analysis. One such information domain, trends in codon usage, can provide a wealth of information about an organism's genes and their expression. Degeneracy in the genetic code allows more than one triplet codon to code for the same amino acid, and usage of these codons is often biased such that one or more of these synonymous codons is preferred. Isolation of translational efficiency bias can have ...


A Framework To Support Spatial, Temporal And Thematic Analytics Over Semantic Web Data, Matthew Steven Perry Jan 2008

A Framework To Support Spatial, Temporal And Thematic Analytics Over Semantic Web Data, Matthew Steven Perry

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Spatial and temporal data are critical components in many applications. This is especially true in analytical applications ranging from scientific discovery to national security and criminal investigation. The analytical process often requires uncovering and analyzing complex thematic relationships between disparate people, places and events. Fundamentally new query operators based on the graph structure of Semantic Web data models, such as semantic associations, are proving useful for this purpose. However, these analysis mechanisms are primarily intended for thematic relationships. This dissertation proposes a framework built around the RDF data model for analysis of thematic, spatial and temporal relationships between named entities ...


Energy Efficient Image Video Sensor Networks, Paul Anthony Bender Jan 2008

Energy Efficient Image Video Sensor Networks, Paul Anthony Bender

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Image Video Sensor Networks are emerging applications for sensor network technologies. The relatively large size of the data collected by image video sensors presents new challenges for the sensor network in terms of energy consumption and channel capacity. We address each of these issues through the use of a high density network deployment utilizing some nodes as dedicated relay nodes.

A high density network allows network nodes to reduce their transmission power. This reduction in transmission power allows each node to conserve power and simultaneously increases the potential for spatially concurrent transmissions within the network, resulting in improved network throughputs ...


Evolutionary Methodology For Optimization Of Image Transforms Subject To Quantization Noise, Michael Ray Peterson Jan 2008

Evolutionary Methodology For Optimization Of Image Transforms Subject To Quantization Noise, Michael Ray Peterson

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Lossy image compression algorithms sacrifice perfect imagereconstruction in favor of decreased storage requirements. Modelossy compression schemes, such as JPEG2000, rely upon the discrete wavelet transform (DWT) to achieve high levels of compression while minimizing the loss of information for image reconstruction. Some compression applications require higher levels of compression than those achieved through application of the DWT and entropy coding. In such lossy systems, quantization provides high compression rates at the cost of increased distortion. Unfortunately, as the amount of quantization increases, the performance of the DWT for accurate image reconstruction deteriorates. Previous research demonstrates that a genetic algorithm can ...


Summaritive Digest For Large Document Repositories With Application To E-Rulemaking, Lijun Chen Jan 2007

Summaritive Digest For Large Document Repositories With Application To E-Rulemaking, Lijun Chen

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Large document repositories need to be organized and summarized to make them more accessible and understandable. Such needs exist in many applications, including web search, e-rulemaking (electronic rulemaking) and document archiving. Even though much has been done in the areas of document clustering and summarization, there are still many new challenges and issues that need to be addressed as the repositories become larger, more prevalent and dynamic. In this dissertation, we investigate more informative ways to organize and summarize large document repositories, especially e-rulemaking feedback repositories (ERFRs), so that the large repositories can be managed and digested more efficiently and ...


Computational Methods For The Objective Review Of Forensic Dna Testing Results, Jason R. Gilder Jan 2007

Computational Methods For The Objective Review Of Forensic Dna Testing Results, Jason R. Gilder

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Since the advent of criminal investigations, investigators have sought a "gold standard" for the evaluation of forensic evidence. Currently, deoxyribonucleic acid (DNA) technology is the most reliable method of identification. Short Tandem Repeat (STR) DNA genotyping has the potential for impressive match statistics, but the methodology not infallible. The condition of an evidentiary sample and potential issues with the handling and testing of a sample can lead to significant issues with the interpretation of DNA testing results. Forensic DNA interpretation standards are determined by laboratory validation studies that often involve small sample sizes. This dissertation presents novel methodologies to address ...


Xml Integrated Environment For Service-Oriented Data Management, Marwan Younes Maarouf Jan 2007

Xml Integrated Environment For Service-Oriented Data Management, Marwan Younes Maarouf

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The proliferation of XML as a family of related standards including a markup language (XML), formatting semantics (XSL style sheets), a linking syntax (XLINK), and appropriate data schema standards have emerged as a de facto standard for encoding and sharing data between various applications. XML is designed to be simple, easily parsed and self-describing. XML is based on and support the idea of separation of concerns: information content is separated from information rendering, and relationships between data elements are provided via simple nesting and references. As the XML content grows, the ability to handle schemaless XML documents becomes more critical ...


Bibliography Tools In The Context Of Www And Latex, Munushree Thummala Jan 2007

Bibliography Tools In The Context Of Www And Latex, Munushree Thummala

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Preparation of academic papers involves not only the creative processes but also the more mechanical tasks such as adjusting the form and style to suit the demands of the publishing journal or conference. Among several packages that help in these rather tedious mechanical tasks, the TEX + LATEX + BibTEX combination is extremely popular. This thesis is about tools that help in the necessary task of citing related work accurately. It focuses on three aspects of this larger bibliography frame work: (i) a survey of existing bibliography formats and tools, (ii) a database view of BibTEX files and functionality that ensues, and ...


High Performance Text Document Clustering, Yanjun Li Jan 2007

High Performance Text Document Clustering, Yanjun Li

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Data mining, also known as knowledge discovery in database (KDD), is the process to discover interesting unknown knowledge from a large amount of data. Text mining is to apply data mining techniques to extract interesting and nontrivial information and knowledge from unstructured text. Text clustering is one of important techniques of text mining, which is the unsupervised classification of similar documents into different groups.

This research focuses on improving the performance of text clustering. We investigated the text clustering algorithms in four aspects: document representation, documents closeness measurement, high dimension reduction and parallelization. We propose a group of high performance ...


An Analysis Of Neutral Drift's Effect On The Evolution Of A Ctrnn Locomotion Controller With Noisy Fitness Evaluation, Gregory Robert Kramer Jan 2007

An Analysis Of Neutral Drift's Effect On The Evolution Of A Ctrnn Locomotion Controller With Noisy Fitness Evaluation, Gregory Robert Kramer

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This dissertation focuses on the evolution of Continuous Time Recurrent Neural Networks (CTRNNs) as controllers for control systems. Existing research suggests that the process of neutral drift can greatly benefit evolution for problems whose fitness landscapes contain large-scale neutral networks. CTRNNs are known to be highly degenerate, providing a possible source of large-scale landscape neutrality, and existing research suggests that neutral drift benefits the evolution of simple CTRNNs. However, there has been no in-depth examination of the effects of neutral drift on complex CTRNN controllers, especially in the presence of noisy fitness evaluation. To address this problem, this dissertation presents ...


Role-Based Access Control For The Open Grid Services Architecture - Data Access And Integration (Ogsa-Dai), Anil L. Pereira Jan 2007

Role-Based Access Control For The Open Grid Services Architecture - Data Access And Integration (Ogsa-Dai), Anil L. Pereira

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Grid has emerged recently as an integration infrastructure for the sharing and coordinated use of diverse resources in dynamic, distributed virtual organizations (VOs). A Data Grid is an architecture for the access, exchange, and sharing of data in the Grid environment. In this dissertation, role-based access control (RBAC) systems for heterogeneous data resources in Data Grid systems are proposed. The Open Grid Services Architecture - Data Access and Integration (OGSA-DAI) is a widely used framework for the integration of heterogeneous data resources in Grid systems.

However, in the OGSA-DAI system, access control causes substantial administration overhead for resource providers in VOs ...


On Optimal Survivability Design In Wdm Optical Networks Under Scheduled Traffic Models, Tianjian Li Jan 2007

On Optimal Survivability Design In Wdm Optical Networks Under Scheduled Traffic Models, Tianjian Li

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Wavelength division multiplexing (WDM) optical networks are widely viewed as the most appropriate choice for future Internet backbone with the potential to fulfill the ever-growing demands for bandwidth. WDM divides the enormous bandwidth of an optical fiber into many non-overlapping wavelength channels, each of which may operate at the rate of 10 Gigabit per second or higher. A failure in a network such as a cable cut may result in a tremendous loss of data. Therefore, survivability is a very important issue in WDM optical networks. The objective of this dissertation is to address the survivability provisioning problem in WDM ...


Data Mining And Analysis On Multiple Time Series Object Data, Chunyu Jiang Jan 2007

Data Mining And Analysis On Multiple Time Series Object Data, Chunyu Jiang

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Huge amount of data is available in our society and the need for turning such data into useful information and knowledge is urgent. Data mining is an important field addressing that need and significant progress has been achieved in the last decade. In several important application areas, data arises in the format of Multiple Time Series Object (MTSO) data, where each data object is an array of time series over a large set of features and each has an associated class or state. Very little research has been conducted towards this kind of data. Examples include computational toxicology, where each ...


Implementation For A Coherent Keyword-Based Xml Query Language, Venkatakalyan Potturi Jan 2007

Implementation For A Coherent Keyword-Based Xml Query Language, Venkatakalyan Potturi

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Due to the increasing pervasiveness of data sets using the XML data format, numerous query languages have been proposed that exploit the structure inherent in XML. Many such query languages, supported by specialized XML search engines, are complex and not suitable for naive users. A simple keyword based query language is described which not only exploits the structure of XML documents to extract relevant fragments, but can also fall back on retrieval through plain text search. This thesis focuses on developing a prototype implementation for a Coherent Keyword Based XML Query Language. It analyzes the typical challenges posed by the ...


An Evolutionary Programming Algorithm For Automatic Chromatogram Alignment, Bonnie Jo Schwartz Jan 2007

An Evolutionary Programming Algorithm For Automatic Chromatogram Alignment, Bonnie Jo Schwartz

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Scientists use liquid chromatography/mass spectrometry (LC/MS) instruments to measure metabolic responses to external stimuli. The data from these instruments can be distorted due to changes in the testing environment. Automating the removal of distortions is crucial in processing the data. The purpose of this thesis is to develop an algorithm that will automate the process.

The data produced by the LC/MS instrument were treated as images and image registration techniques were applied. A polynomial transformation function was assumed. An evolutionary programming algorithm was used to determine the coefficients of the polynomial. The data was manipulated to determine ...


Comparative Microarray Data Mining, Shihong Mao Jan 2007

Comparative Microarray Data Mining, Shihong Mao

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As a revolutionary technology, microarrays have great potential to provide genome-wide patterns of gene expression, to make accurate medical diagnosis, and to explore genetic causes underlying diseases. It is commonly believed that suitable analysis of microarray datasets can lead to achieve the above goals. While much has been done in microarray data mining, few previous studies, if any, focused on multiple datasets at the comparative level. This dissertation aims to fill this gap by developing tools and methods for set-based comparative microarray data mining. Specifically, we mine highly differentiative gene groups (HDGGs) from given datasets/classes, evaluate the concordance of ...


A Hybrid Approach To Retrieving Web Documents And Semantic Web Data, Trivikram Immaneni Jan 2007

A Hybrid Approach To Retrieving Web Documents And Semantic Web Data, Trivikram Immaneni

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The Semantic Web has been evolving into a property-linked web of RDF data, conceptually divorced from (but physically housed in) the World Wide Web of hyperlinked documents. Data Retrieval techniques are typically used to retrieve data from the Semantic Web while Information Retrieval techniques are used to retrieve documents from the Hypertext Web. Conceptually unifying the two webs enables the exploitation of their interconnections resulting in benefits to both data and document retrieval. Towards this end, we present the Unified Web model that integrates the two webs and formalizes the structure and the semantics of their interconnections. We present a ...


An Analog Evolvable Hardware Device For Active Control, Saranyan A. Vigraham Jan 2007

An Analog Evolvable Hardware Device For Active Control, Saranyan A. Vigraham

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The field of Evolvable Hardware (EH) has recently gained a lot of interest due to the novel methodology it offers for designing electrical circuits and machines. EH techniques involve configuring a reconfigurable hardware platform with the aid of learning engines such as evolutionary algorithms. The EH devices normally act as closed loop controllers with the capability of learning necessary control laws adaptively. Current EH practices have several shortcomings, which have restricted their use as reliable controllers. This dissertation will present an improved EH device based on behavioral reconfigurability that addresses the current open challenges in the field of analog Evolvable ...


Investigating The Male-Driven Evolution Hypothesis Using Human AluRepeat Elements, Sridhar Ramachandran Jan 2006

Investigating The Male-Driven Evolution Hypothesis Using Human AluRepeat Elements, Sridhar Ramachandran

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Thousands of copies of short interspersed repeats (SINEs) are scattered essentially ran-domly through the human genome. Although copies of each repeat subfamily are identical at the time of their insertion, they become subject to individual substitutions after insertion. As the relative time of insertion is known for many of these repeats, such "junk DNA" can be used to provide a sizeable number of time-series data points for studying substitution effects in a variety of genomic contexts. This dissertation specifically discusses the usefulness of the Alufamily of SINE repeats towards addressing open problems in genomics, population genetics, and biology in ...


A Formal Language Approach For Detecting Texture Paths And Patterns In Images, Prithviraj S. Patil Jan 2006

A Formal Language Approach For Detecting Texture Paths And Patterns In Images, Prithviraj S. Patil

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This Master thesis considers the use of formal languages representation for image processing, especially texture patterns and determining texture paths in them. The texture paths are detected and extracted by using image processing techniques, such as image segmentation to isolate regions of interest, and then the extraction of repeating textures. The detection of the texture blocks is obtained by recursively using 27 X 27, 9 X 9, and 3 X 3 windows. Predefined repeating texture patterns are also searched for in each of the sets. For each set of texture blocks with similar or same characteristics, curve fitting techniques are ...


Simulation And Analysis Of Rfid Localization Algorithms, Zubin Shah Jan 2006

Simulation And Analysis Of Rfid Localization Algorithms, Zubin Shah

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Radio frequency identification (RFID) based localization systems provide a unique approach to localize mobile entities equipped with RFID readers or tagged with RFID tags. UHF RFID systems using passive tags are a good choice considering their cost, reading range, and reliability. With global acceptance and deployment of UHF RFID systems using passive tags for tracking and identification, virtually everything around us can be tagged with small and low-cost passive RFID tags. This thesis describes a Monte Carlo Localization based algorithm to localize a mobile RFID reader within a tagged environment. A software tool is developed to validate this localization process ...


A Field Programmable Gate Array Architecture For Two-Dimensional Partial Reconfiguration, Fei Wang Jan 2006

A Field Programmable Gate Array Architecture For Two-Dimensional Partial Reconfiguration, Fei Wang

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Reconfigurable machines can accelerate many applications by adapting to their needs through hardware reconfiguration. Partial reconfiguration allows the reconfiguration of a portion of a chip while the rest of the chip is busy working on tasks. Operating system models have been proposed for partially reconfigurable machines to handle the scheduling and placement of tasks. They are called OS4RC in this dissertation. The main goal of this research is to address some problems that come from the gap between OS4RC and existing chip architectures and the gap between OS4RC models and practical applications. Some existing OS4RC models are based on an ...


Pattern Recognition Via Machine Learning With Genetic Decision-Programming, Carl C. Hoff Jan 2005

Pattern Recognition Via Machine Learning With Genetic Decision-Programming, Carl C. Hoff

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In the intersection of pattern recognition, machine learning, and evolutionary computation is a new search technique by which computers might program themselves. That technique is called genetic decision-programming. A computer can gain the ability to distinguish among the things that it needs to recognize by using genetic decision-programming for pattern discovery and concept learning. Those patterns and concepts can be easily encoded in the spines of a decision program (tree or diagram). A spine consists of two parts: (1) the test-outcome pairs along a path from the program's root to any of its leaves and (2) the conclusion in ...