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Theses and Dissertations

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Articles 1741 - 1770 of 2733

Full-Text Articles in Computer Sciences

Gene Network Inference And Expression Prediction Using Recurrent Neural Networks And Evolutionary Algorithms, Heather Y. Chan Dec 2010

Gene Network Inference And Expression Prediction Using Recurrent Neural Networks And Evolutionary Algorithms, Heather Y. Chan

Theses and Dissertations

We demonstrate the success of recurrent neural networks in gene network inference and expression prediction using a hybrid of particle swarm optimization and differential evolution to overcome the classic obstacle of local minima in training recurrent neural networks. We also provide an improved validation framework for the evaluation of genetic network modeling systems that will result in better generalization and long-term prediction capability. Success in the modeling of gene regulation and prediction of gene expression will lead to more rapid discovery and development of therapeutic medicine, earlier diagnosis and treatment of adverse conditions, and vast advancements in life science research.

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Asynchronous Database Drivers, Michael Adam Heath Dec 2010

Asynchronous Database Drivers, Michael Adam Heath

Theses and Dissertations

Existing database drivers use blocking socket I/O to exchange data with relational database management systems (RDBMS). To concurrently send multiple requests to a RDBMS with blocking database drivers, a separate thread must be used for each request. This approach has been used successfully for many years. However, we propose that using non-blocking socket I/O is faster and scales better under load. In this paper we introduce the Asynchronous Database Connectivity in Java (ADBCJ) framework. ADBCJ provides a common API for asynchronous RDBMS interaction. Various implementations of the ADBCJ API are used to show how utilizing non-blocking socket I/O is faster …

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Drop-In Concurrent Api Replacement For Exploration, Test, And Debug, Everett Allen Morse Dec 2010

Drop-In Concurrent Api Replacement For Exploration, Test, And Debug, Everett Allen Morse

Theses and Dissertations

Complex concurrent APIs are difficult to reason about annually due to the exponential growth in the number of feasible schedules. Testing against reference solutions of these APIs is equally difficult as reference solutions implement an unknown set of allowed behaviors, and programmers have no way to directly control schedules or API internals to expose or reproduce errors. The work in this paper mechanically generates a drop-in replacement for a concurrent API from a formal specification. The specification is a guarded command system with first-order logic that is compiled into a core calculus. The term rewriting system is connected to actual …

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Technologies Of Mobile Communication, Monika Margilaj Nov 2010

Technologies Of Mobile Communication, Monika Margilaj

Theses and Dissertations

Long-Term Evolution (LTE) is a new technology recently specified by 3GPP-Third Generation Partnership Project on the way towards fourth-generation mobile. This thesis presents the main technical features of this technology as well as its performances in terms of peak bit rate and average cell throughput, among others. LTE entails a big technological improvement as compared with the previous 3G standards. 1 However, this thesis also demonstrates that LTE performances do not fulfill the technical requirements established by ITU-R to classify one radio access technology as a member of the IMT-Advanced family of standards. Thus, this thesis describes the procedure followed …

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Packing Virtual Machines Onto Servers, David Luke Wilcox Oct 2010

Packing Virtual Machines Onto Servers, David Luke Wilcox

Theses and Dissertations

Data centers consume a significant amount of energy. This problem is aggravated by the fact that most servers and desktops are underutilized when powered on, and still consume a majority of the energy of a fully utilized computer even when idle This problem would be much worse were it not for the growing use of virtual machines. Virtual machines allow system administrators to more fully utilize hardware capabilities by putting more than one virtual system on the same physical server. Many times, virtual machines are placed onto physical servers inefficiently. To address this inefficiency, I developed a new family of …

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Histogram Based Video Segmentation And Key Frame Extraction On Som And Dft, Songul Cecen Oct 2010

Histogram Based Video Segmentation And Key Frame Extraction On Som And Dft, Songul Cecen

Theses and Dissertations

A new key-frame extraction method, called "index-based retrieval (I-Base)", is presented based on DCT and SOM. It allows user to quickly find particular point within a certain domain and/or determine if the domain is relevant to the need. I-Base forms a hierarchy from the uniquely represented shots by using frames. Eventually the use of hierarchy leads to the generation of video content indexing. Doing so allows the user to map only the relevant section in the source with the request issued. The idea of 'just request-to-response mapping' prevents not only the unwanted information retrieval, but also saves time and bandwidth. …

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Pixel Based Note Taking Through Perceptual Structure Inference, Mitchell Kent Harris Oct 2010

Pixel Based Note Taking Through Perceptual Structure Inference, Mitchell Kent Harris

Theses and Dissertations

Knowledge workers need effective annotation tools to assimilate information. Unfortunately many digital annotators are limited in the range of document that they accept. Those that do accept many different documents do so by converting documents to images, thus losing any awareness about the original content of the document. We introduce a digital note taker that is both universal and content aware. By constructing a hierarchical context tree of document images, the structure of a document is inferred from the image. This hierarchical context tree is shown to be useful by demonstrating how it facilitates selection of document elements, reflowing documents …

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Relational Database Management Systems (Rdms) Sistemet E Menaxhimit Te Bazës Së Të Dhënave Relacionale, Visar Kastrati Oct 2010

Relational Database Management Systems (Rdms) Sistemet E Menaxhimit Te Bazës Së Të Dhënave Relacionale, Visar Kastrati

Theses and Dissertations

Informacionet janë burime mjaft të vlefshme në një organizatë. Softuerët kompjuterik sigurojnë një mënyrë efikase të procesimit të informatave, ku sistemet e bazave të të dhënave janë duke pësuar një rritje mjaft të madhe dhe janë bërë mjaft të zakonshme me anë të cilave bëhet e mundur të ruhen dhe të korrigjohen informatat në mënyrë efektive. Tema mbulon një krahasim në mes të sistemeve te menaxhimit të bazave të të dhënave (database management system). Kjo siguron që të krijohet një kuptim më i mirë i modelimit relacional të të dhënave (relational data modeling), qëllimin e tyre, natyrën dhe standardet të …

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Improving Information Products For System 2 Decision Support, Neal Gibson Sep 2010

Improving Information Products For System 2 Decision Support, Neal Gibson

Theses and Dissertations

The creation, maintenance, and management of Information Product (IP) systems that are used by organizations for complex decisions represent a unique set of challenges. These challenges are compounded when the purpose of such a systems is also for knowledge creation and dissemination. Information quality research to date has focused mainly upon treating IP independent from the actual users, despite the obvious interdependency between the two. Research in cognitive psychology has established a dual-process model for human cognition. Designing IP systems in recognition of these differing methods of human cognition represents a new approach to improving their quality. Education data and …

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Knowledge-Driven Identity Resolution For Longitudinal Education Data, Greg Holland Sep 2010

Knowledge-Driven Identity Resolution For Longitudinal Education Data, Greg Holland

Theses and Dissertations

Data sets containing information for an overlapping group of real-world identities present a very high likelihood that the identifying attributes and attribute values for these identities may be inconsistent between the data sets. Differences in the types of identifying attributes or attribute values inhibit proper record linkage and identity resolution. Traditional approaches to record linkage are commonly utilized however the results from these approaches do not demonstrate the highest possible levels of confidence and utility. Syntax, semantics, and temporal aspects of data sets should be understood and incorporated into the methodology of heterogeneous data set integration. Domain-specific expertise is a …

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A Java Prototype Implementation Of Coordination For Heterogeneous, Distributed, And Parallel Programming, Hao Wu Sep 2010

A Java Prototype Implementation Of Coordination For Heterogeneous, Distributed, And Parallel Programming, Hao Wu

Theses and Dissertations

Heterogeneous distributed parallel programming skills are in rapidly rising demand for developing applications in emerging fields such as MRI spin relaxometry, gene sequence analysis, climate modeling, and molecular modeling of potential bioactive compounds that require massive amounts of computation. However, heterogeneous distributed and parallel programming is not a trivial task for programmers. Programmers are overwhelmed to program at a low level with specific target machines or are faced with unfamiliar programming models. In this thesis, we introduce a framework to support heterogeneous distributed programming in a sequential programming language Java for parallelism. The framework has four layers (application layer, coordination …

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Statistical Image Recovery From Laser Speckle Patterns With Polarization Diversity, Donald B. Dixon Sep 2010

Statistical Image Recovery From Laser Speckle Patterns With Polarization Diversity, Donald B. Dixon

Theses and Dissertations

This research extends the theory and understanding of the laser speckle imaging technique. This non-traditional imaging technique may be employed to improve space situational awareness and image deep space objects from a ground-based sensor system. The use of this technique is motivated by the ability to overcome aperture size limitations and the distortion effects from Earth’s atmosphere. Laser speckle imaging is a lensless, coherent method for forming two-dimensional images from their autocorrelation functions. Phase retrieval from autocorrelation data is an ill-posed problem where multiple solutions exist. This research introduces polarization diversity as a method for obtaining additional information so the …

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Cyber Situational Awareness Using Live Hypervisor-Based Virtual Machine Introspection, Dustyn A. Dodge Sep 2010

Cyber Situational Awareness Using Live Hypervisor-Based Virtual Machine Introspection, Dustyn A. Dodge

Theses and Dissertations

In this research, a compiled memory analysis tool for virtualization (CMAT-V) is developed as a virtual machine introspection (VMI) utility to conduct live analysis during cyber attacks. CMAT-V leverages static memory dump analysis techniques to provide live dynamic system state data. Unlike some VMI applications, CMAT-V bridges the semantic gap using derivation techniques. CMAT-V detects Windows-based operating systems and uses the Microsoft Symbol Server to provide this context to the user. This research demonstrates the usefulness of CMAT-V as a situational awareness tool during cyber attacks, tests the detection of CMAT-V from the guest system level and measures its impact …

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Accelerating Malware Detection Via A Graphics Processing Unit, Nicholas S. Kovach Sep 2010

Accelerating Malware Detection Via A Graphics Processing Unit, Nicholas S. Kovach

Theses and Dissertations

Real-time malware analysis requires processing large amounts of data storage to look for suspicious files. This is a time consuming process that (requires a large amount of processing power) often affecting other applications running on a personal computer. This research investigates the viability of using Graphic Processing Units (GPUs), present in many personal computers, to distribute the workload normally processed by the standard Central Processing Unit (CPU). Three experiments are conducted using an industry standard GPU, the NVIDIA GeForce 9500 GT card. The goal of the first experiment is to find the optimal number of threads per block for calculating …

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Hijacking User Uploads To Online Persistent Data Repositories For Covert Data Exfiltration, Curtis P. Barnard Sep 2010

Hijacking User Uploads To Online Persistent Data Repositories For Covert Data Exfiltration, Curtis P. Barnard

Theses and Dissertations

As malware has evolved over the years, it has gone from harmless programs that copy themselves into other executables to modern day botnets that perform bank fraud and identity theft. Modern malware often has a need to communicate back to the author, or other machines that are also infected. Several techniques for transmitting this data covertly have been developed over the years which vary significantly in their level of sophistication. This research creates a new covert channel technique for stealing information from a network by piggybacking on user-generated network traffic. Specifically, steganography drop boxes and passive covert channels are merged …

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A Comparative Analysis Of Ascii And Xml Logging Systems, Eric C. Hanington Sep 2010

A Comparative Analysis Of Ascii And Xml Logging Systems, Eric C. Hanington

Theses and Dissertations

This research compares XML and ASCII based event logging systems in terms of their storage and processing efficiency. XML has been an emerging technology, even for security. Therefore, it is researched as a logging system with the mitigation of its verbosity. Each system consists of source content, the network transmission, database storage, and querying which are all studied as individual parts. The ASCII logging system consists of the text file as source, FTP as transport, and a relational database system for storage and querying. The XML system has the XML files and XML files in binary form using Efficient XML …

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Reputation-Based Internet Protocol Security: A Multilayer Security Framework For Mobil Ad Hoc Networks, Timothy H. Lacey Sep 2010

Reputation-Based Internet Protocol Security: A Multilayer Security Framework For Mobil Ad Hoc Networks, Timothy H. Lacey

Theses and Dissertations

This research effort examines the theory, application, and results for a Reputation-based Internet Protocol Security (RIPSec) framework that provides security for an ad-hoc network operating in a hostile environment. In RIPSec, protection from external threats is provided in the form of encrypted communication links and encryption-wrapped nodes while internal threats are mitigated by behavior grading that assigns reputations to nodes based on their demonstrated participation in the routing process. Network availability is provided by behavior grading and round-robin multipath routing. If a node behaves faithfully, it earns a positive reputation over time. If a node misbehaves (for any number of …

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Code White: A Signed Code Protection Mechanism For Smartphones, Joseph M. Hinson Iv Sep 2010

Code White: A Signed Code Protection Mechanism For Smartphones, Joseph M. Hinson Iv

Theses and Dissertations

This research develops Code White, a hardware-implemented trusted execution mechanism for the Symbian mobile operating system. Code White combines a signed whitelist approach with the execution prevention technology offered by the ARM architecture. Testing shows that it prevents all untrusted user applications from executing while allowing all trusted applications to load and run. Performance testing in contrast with an unmodified Symbian system shows that the difference in load time increases linearly as the application file size increases. The predicted load time for an application with a one megabyte code section remains well below one second, ensuring uninterrupted experience for the …

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Php & Mysql Simple Project Management Application, Vedat Shaqiri Sep 2010

Php & Mysql Simple Project Management Application, Vedat Shaqiri

Theses and Dissertations

Starting building an application is not that easy at all, especially when people are not experienced enough with the tools needed to cook it. This thesis contains a brief introduction to an PHP & MySQL application. Just as said some lines before, when you get into a thing that you might not be familiar with, difficulties appear, at this time patience and dedication come in to play realizing and making it become true. PHP and MySQL offer a great opportunity building dynamic web sites and application. It is not PHP that makes a web site or an application to become …

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Windows Xp Embedded Operating System Design, Bashkim Çerkini Sep 2010

Windows Xp Embedded Operating System Design, Bashkim Çerkini

Theses and Dissertations

Windows XP embedded (XPe) është para se gjithash një komplet i veglave që mundëson ndërtimin e një versioni me porosi të Windows XP Professional. Duke zgjedhur vetëm komponentët qe ju nevojitën mund të zhvillohet një sistem operativ (SO) me të gjitha karakteristikat që i kërkon projekti përkatës. Kjo domethënë se programet e zakonshme të Windows-it duke përfshire edhe programet .NET based mund të ekzekutohen në sistemin operativ tuaj përderisa ju i keni përfshirë të gjitha komponentët që programi juaj mbështetët. Për shembull nuk mund të ekzekutoni asnjë aplikacion të rrjetit pa i perfshirë komponentet e rrjetit.Windows XP Embedded është një …

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Unusual-Object Detection In Color Video For Wilderness Search And Rescue, Daniel Richard Thornton Aug 2010

Unusual-Object Detection In Color Video For Wilderness Search And Rescue, Daniel Richard Thornton

Theses and Dissertations

Aircraft-mounted cameras have potential to greatly increase the effectiveness of wilderness search and rescue efforts by collecting photographs or video of the search area. The more data that is collected, the more difficult it becomes to process it by visual inspection alone. This work presents a method for automatically detecting unusual objects in aerial video to assist people in locating signs of missing persons in wilderness areas. The detector presented here makes use of anomaly detection methods originally designed for hyperspectral imagery. Multiple anomaly detection methods are considered, implemented, and evaluated. These anomalies are then aggregated into spatiotemporal objects by …

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Backflip: A Principled Approach To Online Attribute Verification, Devlin R. Daley Aug 2010

Backflip: A Principled Approach To Online Attribute Verification, Devlin R. Daley

Theses and Dissertations

As traditional interactions in the real-word move online, services that require verified personal information from web users will increase. We propose an architecture for the verification of web user attributes without the use of cryptographic-based credentials. In this architecture, service providers are delegated a user's ability to directly contact a certifying party and retrieve attribute data. We demonstrate that this approach is simple for both developers and users, can be applied to existing Internet facilities and sufficiently secure for typical web use cases.

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Interactive Object Selection And Matting For Video And Images, Brian L. Price Aug 2010

Interactive Object Selection And Matting For Video And Images, Brian L. Price

Theses and Dissertations

Video segmentation, the process of selecting an object out of a video sequence, is a fundamentally important process for video editing and special effects. However, it remains an unsolved problem due to many difficulties such as large or rapid motions, motion blur, lighting and shadow changes, complex textures, similar colors in the foreground and background, and many others. While the human vision system relies on multiple visual cues and higher-order understanding of the objects involved in order to perceive the segmentation, current algorithms usually depend on a small amount of information to assist a user in selecting a desired object. …

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Text Segmentation Of Historical Degraded Handwritten Documents, Oliver Nina Aug 2010

Text Segmentation Of Historical Degraded Handwritten Documents, Oliver Nina

Theses and Dissertations

The use of digital images of handwritten historical documents has increased in recent years. This has been possible through the Internet, which allows users to access a vast collection of historical documents and makes historical and data research more attainable. However, the insurmountable number of images available in these digital libraries is cumbersome for a single user to read and process. Computers could help read these images through methods known as Optical Character Recognition (OCR), which have had significant success for printed materials but only limited success for handwritten ones. Most of these OCR methods work well only when the …

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Partition Based Phylogenetic Search, Kenneth A. Sundberg Aug 2010

Partition Based Phylogenetic Search, Kenneth A. Sundberg

Theses and Dissertations

Evolutionary relationships are key to modern understanding of biological systems. Phylogenetic search is the means by which these relationships are inferred. Phylogenetic search is NP-Hard. As such it is necessary to employ heuristic methods. This work proposes new methods based on viewing the relationships between species as sets of partitions. These methods produce more parsimonious phylogenies than current methods.

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Windows Azure: Using Windows Azure's Service Bus To Solve Data Security Issues, Don Chambers Aug 2010

Windows Azure: Using Windows Azure's Service Bus To Solve Data Security Issues, Don Chambers

Theses and Dissertations

Many of the largest technology companies are heavily investing in Cloud Computing technology, making this a major force in the realm of software development. However, this software paradigm brings with it significant data related security issues. This paper discusses some of these security issues and presents a solution. The solution calls for storing data outside of the cloud, and under the control of the cloud consumer. In addition, the solution provides the ability to manipulate data using only the standard HTTP ports that are typically opened at most locations. This solution is implemented using Microsoft's Windows Azure Cloud Computing operating …

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A Probabilistic Morphological Analyzer For Syriac, Peter J. Mcclanahan Jul 2010

A Probabilistic Morphological Analyzer For Syriac, Peter J. Mcclanahan

Theses and Dissertations

We show that a carefully crafted probabilistic morphological analyzer significantly outperforms a reasonable, naive baseline for Syriac. Syriac is an under-resourced Semitic language for which there are no available language tools such as morphological analyzers. Such tools are widely used to contribute to the process of annotating morphologically complex languages. We introduce and connect novel data-driven models for segmentation, dictionary linkage, and morphological tagging in a joint pipeline to create a probabilistic morphological analyzer requiring only labeled data. We explore the performance of this model with varying amounts of training data and find that with about 34,500 tokens, it can …

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Electronic Library Database Application, Visar Nura Jul 2010

Electronic Library Database Application, Visar Nura

Theses and Dissertations

It's probably fair to say that most business-oriented computer applications work with data in one form or another. This data often is stored in one or more databases. Visual Basic can create powerful data management programs with a little planning and effort. The most fundamental part of that planning is in how the data is structured. A poorly designed database can doom even the most well-intentioned program from the start. On the other hand, a well-designed database can make a programmer's life much easier. Creating an organized data structure requires you to learn about two separate tasks. First, you must …

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Practical Improvements In Applied Spectral Learning, Adam C. Drake Jun 2010

Practical Improvements In Applied Spectral Learning, Adam C. Drake

Theses and Dissertations

Spectral learning algorithms, which learn an unknown function by learning a spectral representation of the function, have been widely used in computational learning theory to prove many interesting learnability results. These algorithms have also been successfully used in real-world applications. However, previous work has left open many questions about how to best use these methods in real-world learning scenarios. This dissertation presents several significant advances in real-world spectral learning. It presents new algorithms for finding large spectral coefficients (a key sub-problem in spectral learning) that allow spectral learning methods to be applied to much larger problems and to a wider …

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Automatic Extraction From And Reasoning About Genealogical Records: A Prototype, Charla Jean Woodbury Jun 2010

Automatic Extraction From And Reasoning About Genealogical Records: A Prototype, Charla Jean Woodbury

Theses and Dissertations

Family history research on the web is increasing in popularity, and many competing genealogical websites host large amounts of data-rich, unstructured, primary genealogical records. It is labor-intensive, however, even after making these records machine-readable, for humans to make these records easily searchable. What we need are computer tools that can automatically produce indices and databases from these genealogical records and can automatically identify individuals and events, determine relationships, and put families together. We propose here a possible solution—specialized ontologies, built specifically for extracting information from primary genealogical records, with expert logic and rules to infer genealogical facts and assemble relationship …

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