Physical Sciences and Mathematics Commons^™

Semsos : An Architecture For Query, Insertion, And Discovery For Semantic Sensor Networks, Joshua Kenneth Pschorr

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With sensors, storage, and bandwidth becoming ever cheaper, there has been a drive recently to make sensor data accessible on the Web. However, because of the vast number of sensors collecting data about our environment, finding relevant sensors on the Web and then interpreting their observations is a non-trivial challenge. The Open Geospatial Consortium (OGC) defines a web service specification known as the Sensor Observation Service (SOS) that is designed to standardize the way sensors and sensor data are discovered and accessed on the Web. Though this standard goes a long way in providing interoperability between sensor data producers and …

Two Fundamental Building Blocks To Provide Quick Reaction Capabilities For The Department Of Defense, Daniel Alan Uppenkamp

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The Department of Defense (DoD) has a need for long-term development efforts in conjunction with short-term development efforts. Ideally, Quick Reaction Capabilities (QRC) would be able to make use of the same processes that are used for Acquisition Programs (AP) with a few modifications to accommodate the accelerated schedule. Unfortunately, APs have a more fundamental problem with both the development process and the development framework. In August of 2007, the agile development process and modular, open source framework discussed in this thesis were two key factors that enabled the Air Force Research Laboratory (AFRL) to successfully deploy AngelFire in support …

A Latent Dirichlet Allocation/N-Gram Composite Language Model, Raymond Daniel Kulhanek

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I present a composite language model in which an n-gram language model is integrated with the Latent Dirichlet Allocation topic clustering model. I also describe a parallel architecture that allows this model to be trained over large corpora and present experimental results that show how the composite model compares to a standard n-gram model over corpora of varying size.

A Hardware Compact Genetic Algorithm For Hover Improvement In An Insect-Scale Flapping-Wing Micro Air Vehicle, Kathleen M. Timmerman

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Wing and airframe damage to insect scale micro air vehicles potentially cause significant losses in pose and position control precision. Although one can imagine many possible means of adapting the flight controllers to restore precise pose and position control, severe limits on computational resources available on-board an insect sized vehicle render many of them impractical. Additionally, limits on sensory capability degrade any such vehicle's ability to critique its own performance. Any adaptive solutions one would propose to recover flight trajectory precision, therefore, would require a resource light implementation, preferably without need for relatively expensive floating-point operations, along with the capability …

Smart Card Based User Authentication, Brandon James

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User authentication plays a very important role in building a secure computing system. In this thesis, we first studied and investigated existing user authentication schemes and some basic concepts of smart cards. We then proposed and implemented an improved user authentication scheme based on the smart card, specifically, Java card. We simulated a web server, and implemented the user authentication scheme with the Java card by programming a Java card applet and a Java program to send commands and receive responses from the card.

The proposed user authentication scheme has two phases: the registration phase and the user authentication phase. …

Developing A Semantic Web Crawler To Locate Owl Documents, Ronald Dean Koron

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The terms Semantic Web and OWL are relatively new and growing concepts in the World Wide Web. Because these concepts are so new there are relatively few applications and/or tools for utilizing the potential power of this new concept. Although there are many components to the Semantic Web, this thesis will focus on the research question, "How do we go about developing a web crawler for the Semantic Web that locates and retrieves OWL documents." Specifically for this thesis, we hypothesize that by giving URIs to OWL documents, including all URIs from within these OWL documents, priority over other types …

Knn-R: Building Secure And Efficient Outsourced Knn Query Service With The Rasp Encryption, Huiqi Xu

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With the wide deployment of public cloud computing infrastructures, outsourcing database services to the cloud has become an appealing solution to save operating expense. However, some databases might be so sensitive or precious that the data owner does not want to move to the cloud unless the security is guaranteed. On the other hand, a secure outsourced service should still provide efficient query processing and significantly reduce the inhouse workload to fully realize the benefits of outsourcing. We summarize these key features for an outsourced service as the CPEL criteria: data Confidentiality, query Privacy, Efficient query processing, and Low inhouse …

Direct Optimization Of Ranking Measures For Learning To Rank Models, Li Li Guo

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The main challenge in learning-to-rank for information retrieval is the difficulty to di- rectly optimize ranking measures to automatically construct a ranking model from training data. It is mainly due to the fact that the ranking measures are determined by the order of ranked documents rather than the specific values of ranking model scores, thus they are non-convex, nondifferentiable and discontinuous. To address this issue, listwise approaches have been proposed where loss functions are defined either by exploiting a probabilistic model or by optimizing upper bounds or smoothed approximations of ranking measures. Even though very promising results have been achieved, …

Enhancing Description Logics For Rules Coverage, David Carral Martinez

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This thesis is a formal study on how to extend the set of logic constructors of description logics languages, used for knowledge representation in the Semantic Web field to capture some of the previously exclusive rules expressivity. Description Logics, the logics underpinning the Web Ontology Language OWL, and rules are currently the most prominent paradigms used for modeling knowledge for the Semantic Web. While both of these approaches are based on classical logic, the paradigms also differ significantly, so that naive combinations result in undesirable properties such as undecidability. Recent work has shown that many rules can in fact be …

Interoperability Between Awsome And Other Tools Using Model Driven Architecture, Chitra Srinivasan

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AFIT Wide Spectrum Object Modeling Environment (AWSOME) is built on an Abstract Syntax Tree (AST) which is the meta-model of AWSOME. Transformations happen internally in AWSOME to transform anything in abstract to concrete. Earlier efforts in AWSOME were focused on developing tools to work on the AST. The goal of this thesis is to make AWSOME interoperable with other available tools. To achieve this goal, the Model Driven Architecture (MDA) concept is used. MDA is a framework aimed at portability, interoperability and reusability among different tools. Among many tools that use MDA context, EclipseUML 2008 and Dresden OCL Toolkit were …

Semi-Supervised Contrafold For Rna Secondary Structure Prediction: A Maximum Entropy Approach, Jianping Feng

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A novel probabilistic discriminative model based on conditional random fields, CONTRAfold, has recently been proposed for single sequence RNA secondary structure prediction. By incorporating most of the features which closely mirror the local interaction terms of thermodynamics-based models, the CONTRAfold model has outperformed both probabilistic and physics-based techniques, and received the highest single sequence prediction accuracies. CONTRAfold, like most other RNA secondary structure prediction techniques, requires a collection of RNA sequences with known secondary structure to serve as training data for the algorithm. Manual annotation of RNA sequences is both expensive and time-consuming, and there remains a great deal more …

Optimizing Memory Cost With Loop Transformations, Hailong Shi

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Embedded systems are usually constrained in terms of timing, power, and memory. Many embedded applications, especially in the multi-media and telecom domains, are inherently data dominant. These embedded DSP applications usually exhibit intensive computations in the form of multi-level loops. The performance of these embedded DSP applications mainly depends on the code quality of the loops and the memory hierarchy design. During the design phase of the embedded system, it is important to estimate the overall storage requirement to guide the memory system design and take advantage of the memory system by program transformations and loop transformations.

Loop transformations including …

Towards Optimal Resource Provisioning For Running Mapreduce Programs In Public Clouds, Fengguang Tian

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Running MapReduce programs in the public cloud introduces the important problem: how to optimize resource provisioning to minimize the financial charge for a specific job? In this thesis, We study the whole process of MapReduce processing and build up a cost function that explicitly models the relationship between the amount of input data, the available system resources (Map and Reduce slots), and the complexity of the Reduce function for the target MapReduce job. The model parameters can be learned from test runs with a small number of nodes on a small amount of data. Based on this cost model, we …

Real Time Semantic Analysis Of Streaming Sensor Data, Harshal Kamlesh Patni

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The emergence of dynamic information sources - like social, mobile and sensors, has led to ginormous streams of real time data on the web also called, the era of Big Data [1]. Research studies suggest, these dynamic networks have created more data in the last three years than in the entire history of civilization, and this trend will only increase in the coming years [1]. Gigaom article on Big data shows, how the total information generated by these dynamic information sources has completely surpassed the total storage capacity. Thus keeping in mind the problem of ever-increasing data, this thesis focuses …

Optimization Of Scientific Computation For Multicore Systems, Andrew B. Mcclain

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With the rapid growth of semiconductor technology, chip density has increased significantly. As the power exponent is setting hard limits to frequency increases, multi-core and chip level multi-processors have become prevalent in recent years to take advantage of the increasing chip density. In the new generation of processors, multi-core architecture design is becoming the major trend: IBM/SONY/Toshiba's Cell Broadband Engine processors contain nine cores; NVIDIA graphics processors contain more than 30 cores.

One of the biggest challenges is to efficiently utilize the computational power provided by multi-core systems. The second challenge to achieving high performance in a computer system is …

Parallel Sorting On Multi-Core Architecture, Wei Wang

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With the limitations given by the power consumption (power wall), memory wall and the instruction level parallelism, the computing industry has turned its direction to multi-core architectures. Nowadays, the multi-core and many-core architectures are becoming the trend of the processor design. But how to exploit these architectures is the primary challenge for the research community. To take advantage of the multi-core architectures, the software design has undergone fundamental changes.

Sorting is a fundamental, important problem in computer science. It is utilized in many applications such as databases and search engines. In this thesis, we will investigate and auto-tune two parallel …

Surveillance In A Smart Home Environment, Ryan Stewart Patrick

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A system for assisting the elderly in maintaining independent living is currently being designed. When mature, it is expected that this system will have the ability to track objects that a resident may lose periodically, detect falls within the home, and alert family members or health care professionals to abnormal behaviors.

This thesis addresses the early stages of this system's development. It presents a survey of the work that has previously been completed in the area of surveillance within a home environment, information on the physical characteristics of the system that is being designed, early results related to this system, …

A Contrast Pattern Based Clustering Algorithm For Categorical Data, Neil Koberlein Fore

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The data clustering problem has received much attention in the data mining, machine learning, and pattern recognition communities over a long period of time. Many previous approaches to solving this problem require the use of a distance function. However, since clustering is highly explorative and is usually performed on data which are rather new, it is debatable whether users can provide good distance functions for the data. This thesis proposes a Contrast Pattern based Clustering (CPC) algorithm to construct clusters without a distance function, by focusing on the quality and diversity/richness of contrast patterns that contrast the clusters in a …

Automated Transforms Of Software Models: A Design Pattern Approach, Brandon Adam Gump

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In the realm of software development, projects are plagued by continuous maintenance at the source code level as well as tedious transformations from formal specifications to source code. Such work consumes a large amount of time only to create complicated, un-intelligible, and un-reusable code that is completely detached from initial design rational. To cope with these problems, The Air Force Institute of Technology (AFIT) Wide Spectrum Object Modeling Environment (AWSOME) was designed to generate specifications that can be transformed into abstract designs and finally into source code. The specifications are written in the AFIT Wide-spectrum Language (AWL) and parsed in …

Computational Analysis Of Metabolomic Toxicological Data Derived From Nmr Spectroscopy, Benjamin J. Kelly

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Nuclear magnetic resonance (NMR) spectroscopy is a non-invasive method of acquiring metabolic profiles from biofluids. The most informative metabolomic features, or biomarkers, may provide keys to the early detection of changes within an organism such as those that result from exposure to a toxin. One major difficulty with typical NMR data, whether it come from a toxicological, medical or other source, is that it features a low sample size relative to the number of variables measured. Thus, traditional pattern recognition techniques are not always feasible. The "curse of dimensionality" is an important consideration in selecting appropriate statistical and pattern recognition …

Investigation And Quantification Of Codon Usage Bias Trends In Prokaryotes, Amanda L. Hanes

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Organisms construct proteins out of individual amino acids using instructions encoded in the nucleotide sequence of a DNA molecule. The genetic code associates combinations of three nucleotides, called codons, with every amino acid. Most amino acids are associated with multiple synonymous codons, but although they result in the same amino acid and thus have no effect on the final protein, synonymous codons are not present in equal amounts in the genomes of most organisms. This phenomenon is known as codon usage bias, and the literature has shown that all organisms display a unique pattern of codon usage. Research also suggests …

A Software Framework For The Design, Testing And Deployment Of Control Systems For Autonomous Robotics, Duane Stanley Bolick Jr.

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Simulation and control of robotic agents are common enough tasks among computer science and engineering researchers that there exists a large variety of software applications, toolkits, and programming frameworks designed to facilitate such research. The intent of this project is to provide an autonomous robotics simulation and control framework with sufficiently useful tools and reference implementations so as to be immediately useful to basic users, as well as easily understood and extended by software developers and robotics researchers.

As such, this document describes the implementation of a general networking toolkit, an autonomous robotics extension framework, and an autonomous robotics simulator …

A System For Incorporating Time-Based Event-Condition-Action Rules Into Business Databases, Christina Marie Steidle

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Human beings handle time-based events continuously; however the passage of time does not play an active part in most business systems because they are typically driven by interaction from human users or other systems. In order to take an action based upon the passage of time it is necessary to build a framework which will monitor the progression of time and a way to define what events the system should be waiting for. This thesis describes such a system, and shows that the system performs as specified. With this system business users are able to build event-condition-action rules using a …

Analysis And Transformation Of Post-Conditions, Abhinav Vasikarla

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Software engineers have been trying for years to develop a software synthesis system that can transform a formal specification model to a design model from which executable code can be generated. AFIT wide spectrum object modeling environment (AWESOME) is one result of their research. AWESOME presents a formal model as an abstract syntax tree. This model consists mainly of object class specifications. The methods in these classes are specified using pre and post-conditions. The intent of this thesis is to support the transformation of post-conditions to code statements. A post-condition is first categorized as dependent or independent relative to other …

Object Similarity Through Correlated Third-Party Objects, Ting Sa

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Given a pair of objects, it is of interest to know how they are related to each other and the strength of their similarity. Many previous studies focused on two types of similarity measures: The first type is based on closeness of attribute values of two given objects, and the second type is based on how often the two objects co-occur in transactions/tuples.

In this thesis we study a new behavior-based similarity measure, which evaluates similarity between two objects by considering how similar their correlated third-party object sets are. Behavior-based similarity can help us find pairs of objects that have …

Performance And Complexity Co-Evaluations Of Mpeg4-Als Compression Standard For Low-Latency Music Compression, Isaac Kevin Matthew

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In this thesis compression ratio and latency of different classical audio music tracks are analyzed with various encoder options of MPEG4ALS. Different tracks of audio music tracks are tested with MPEG4-ALS coder with different options to find the optimum values for various parameters to obtain maximum compression ratio with minimum CPU time (encoder and decoder time). Optimum frame length for which the compression ratio saturates for music audio is found out by analyzing the results when different classical music tracks are experimented with various frame lengths. Also music tracks with varying sampling rate are tested and the compression ratio and …

Fuel Flow Control Issue In Jet Engines: An Evolvable Hardware Approach, Kshitij S. Deshpande

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Dealing with unexpected dynamic loads in Jet and Turbine engines have always been a matter of concern and an active area of research. This thesis is an initial attempt to apply Evolvable Hardware methods for augmenting classical control methods in a generic turbine engine model. In this work, the Air Force Research Laboratory Generic Turbine Engine Model was converted into C and interfaced with a simulation of a EH VLSI control chip currently under development. The simulated EH device was allowed to evolve to augment the simulated engine's standard FADEC controller so that the whole system could tolerate unexpected, large …

Classification Of Microarray Data To Predict Toxic Exposure, Tarek A. Seleem

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This thesis presents a software system for the analysis of microarray data. Microarrays are a relatively new technology that can be used to examine the state of the genome of an organism at some instant in time. The challenge is the amount of natural variation in biological systems limits our ability to identify specific genes that may be sensitive to changes in an organism's physiology or its environment. The analysis software consists of three modules. The first module filters microarray data to reduce the complexity of the problem. The second module selects subsets of genes for evaluation using a genetic …

Transformation Of Formally Defined Post-Conditions Into Target Language Statements, Swetha Padma Parvathaneni

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For years software engineering researchers have been trying to come up with a software synthesis system that can transform a formal specification model into a design model from which executable code can be generated. AFIT Wide Spectrum Object Modeling Environment (AWSOME) is one such formal based software synthesis system. In this system formal specifications written in AWL are parsed into an AST (Abstract Syntax Tree). The intent of this thesis is to demonstrate the transformation of the postconditions of a method into target language statements. The methods in the classes are specified using pre-conditions and post-conditions. Transforms are developed to …

Analysis Of Very Large Scale Image Data Using Out-Of-Core Technique And Automated 3d Reconstruction Using Calibrated Images, Chandrashekara Hassan Raju

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Analysis of large scale volumetric data sets is very important from the researcher's and technological point of view as it helps in understanding and analyzing the original data. For example, when analyzing volumetric images from cast arteries of pigs, it is essential to apply a suitable segmentation in order to retrieve morphometric data from the scanned image. Due to improved scanning technology, such as MicroCT, these scanned images can get as large as several gigabytes in size. In order to analyze such large scale data sets on common desktop computers is a challenge due to limited main memory. By using …