Physical Sciences and Mathematics Commons^™

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 …

Human Action Recognition By Principal Component Analysis Of Motion Curves, Daniel Stephen Chivers

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Human action recognition is used to automatically detect and recognize actions per- formed by humans in a video. Applications include visual surveillance, human-computer interaction, and robot intelligence, to name a few. An example of a surveillance application is a system that monitors a large public area, such as an airport, for suspicious activity. In human-machine interaction, computers may be controlled by simple human actions. For example, the motion of an arm may instruct the computer to rotate a 3-D model that is being displayed. Human action recognition is also an important capability of intelligent robots that interact with humans.

General …

Behavioral Signature-Based Framework For Identifying Unsatisfiable Variable Mappings Between Digital Designs, Vaibhav Uday Tendulkar

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Throughout its design process (from specification to implementation) a digital circuit goes through a variety of structural changes. These changes are introduced primarily due to the use of automated tools in the design process. Checking whether the Boolean functions representing the two designs are equivalent is thus necessary to verify if a design implementation adheres to its specification. Combinational Equivalence Checking (CEC) - a process of determining whether two combinational design functions are equiv-alent, has been one of the most researched Boolean matching problems. The well-known CEC techniques that have been proposed adopt some kind of a formal approach such …

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. …

Knowledge Acquisition In A System, Christopher J. Thomas

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I present a method for growing the amount of knowledge available on the Web using a hermeneutic method that involves background knowledge, Information Extraction techniques and validation through discourse and use of the extracted information.

I present the metaphor of the "Circle of Knowledge on the Web". In this context, knowledge acquisition on the web is seen as analogous to the way scientific disciplines gradually increase the knowledge available in their field.

Here, formal models of interest domains are created automatically or manually and then validated by implicit and explicit validation methods before the statements in the created models can …

Optimization Of Spectrum Allocation In Cognitive Radio And Dynamic Spectrum Access Networks, Tao Zhang

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Spectrum has become a treasured commodity. However, many licensed frequency bands exclusively assigned to the primary license holders (also called primary users) remain relatively unused or under-utilized for most of the time. Allowing other users (also called secondary users) without a license to operate in these bands with no interference becomes a promising way to satisfy the fast growing needs for frequency spectrum resources. A cognitive radio adapts to the environment it operates in by sensing the spectrum and quickly decides on appropriate frequency bands and transmission parameters to use in order to achieve certain performance goals. One of the …

Abstraction Driven Application And Data Portability In Cloud Computing, Ajith Harshana Ranabahu

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Cloud computing has changed the way organizations create, manage, and evolve their applications. While many organizations are eager to use the cloud, tempted by substantial cost savings and convenience, the implications of using clouds are still not well understood. One of the major concerns in cloud adoption is the vendor lock-in of applications, caused by the heterogeneity of the numerous cloud service offerings. Vendor locked applications are difficult, if not impossible to port from one cloud system to another, forcing cloud service consumers to use undesired or suboptimal solutions. This dissertation investigates a complete and comprehensive solution to address the …

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 …

Winding Resistance And Winding Power Loss Of High-Frequency Power Inductors, Rafal P. Wojda

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The scope of this research is concentrated on analytical winding size optimization (thickness or diameter) of high-frequency power inductors wound with foil, solid-round wire, multi-strand wire, and litz-wire conductors.

The first part of this research concerns analytical optimization of the winding size (thickness or diameter) for the inductors conducting a sinusoidal current. Estimation of winding resistance in individual inductor layers made of foil, taking into account the skin and proximity effects is performed. Approximated equations for the winding power loss in each layer are given and the optimal values of foil thickness for each layer are derived.

A low- and …

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, …

Linked Open Data Alignment & Querying, Prateek Jain

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The recent emergence of the "Linked Data" approach for publishing data represents a major step forward in realizing the original vision of a web that can "understand and satisfy the requests of people and machines to use the web content" i.e. the Semantic Web. This new approach has resulted in the Linked Open Data (LOD) Cloud, which includes more than 295 large datasets contributed by experts belonging to diverse communities such as geography, entertainment, and life sciences. However, the current interlinks between datasets in the LOD Cloud, as we will illustrate,are too shallow to realize much of the benefits promised. …

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 …