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Thor: The Hybrid Online Repository, Timothy W. Van Der Horst Mar 2005

Thor: The Hybrid Online Repository, Timothy W. Van Der Horst

Theses and Dissertations

Digital credentials enable users to perform secure interactions by proving either their identity or that they posses certain attributes. Special care is taken to protect these credentials and their associated private keys during transaction time. However, protection of these items outside of the transaction is often delegated to a secure credential repository. A mobile environment creates significant challenges for secure repositories. We examine these challenges with respect to existing repository practices and produce a set of requirements that a repository must meet in order to cope with the harshness of a mobile environment. We also present the design and implementation …

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Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 21, Number 6, March 2005, College Of Engineering And Computer Science, Wright State University Mar 2005

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 21, Number 6, March 2005, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

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Adaptive Decision Support For Planning Under Hard And Soft Constraints, Alex Dekhtyar, Raphael Finkel, Judy Goldsmith, Beth Goldstein, Cynthia Isenhour Mar 2005

Adaptive Decision Support For Planning Under Hard And Soft Constraints, Alex Dekhtyar, Raphael Finkel, Judy Goldsmith, Beth Goldstein, Cynthia Isenhour

Computer Science and Software Engineering

We describe the “Welfare to Work” scenario, and the software we are designing to support case managers’ planning for their clients.

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Who Counts Your Votes?, Halina Kaminski, Lila Kari, Mark Perry Mar 2005

Who Counts Your Votes?, Halina Kaminski, Lila Kari, Mark Perry

Computer Science Publications

Open and fair elections are paramount to modern democracy. Although some people claim that the penciland- paper systems used in countries such as Canada and UK are still the best method of avoiding vote rigging, recent election problems have sparked great interest in managing the election process through the use of electronic voting systems. It is a goal of this paper to describe a voting system that is secret and secure as well as verifiable and useable over an existing computer network. We have designed and implemented an electronic voting system – Verifiable E-Voting (VEV) – with an underlying protocol …

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An Information Extraction Approach To Reorganizing And Summarizing Specifications, Krishnaprasad Thirunarayan, Aaron Berkovich, Dan Z. Sokol Mar 2005

An Information Extraction Approach To Reorganizing And Summarizing Specifications, Krishnaprasad Thirunarayan, Aaron Berkovich, Dan Z. Sokol

Kno.e.sis Publications

Materials and Process Specifications are complex semi-structured documents containing numeric data, text, and images. This article describes a coarse-grain extraction technique to automatically reorganize and summarize spec content. Specifically, a strategy for semantic-markup, to capture content within a semantic ontology, relevant to semi-automatic extraction, has been developed and experimented with. The working prototypes were built in the context of Cohesia's existing software infrastructure, and use techniques from Information Extraction, XML technology, etc.

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Divide-And-Approximate: A Novel Constraint Push Strategy For Iceberg Cube Mining, Ke Wang, Yuelong Jiang, Jeffrey Xu Yu, Guozhu Dong, Jiawei Han Mar 2005

Divide-And-Approximate: A Novel Constraint Push Strategy For Iceberg Cube Mining, Ke Wang, Yuelong Jiang, Jeffrey Xu Yu, Guozhu Dong, Jiawei Han

Kno.e.sis Publications

The iceberg cube mining computes all cells v, corresponding to GROUP BY partitions, that satisfy a given constraint on aggregated behaviors of the tuples in a GROUP BY partition. The number of cells often is so large that the result cannot be realistically searched without pushing the constraint into the search. Previous works have pushed antimonotone and monotone constraints. However, many useful constraints are neither antimonotone nor monotone. We consider a general class of aggregate constraints of the form f(v)θσ, where f is an arithmetic function of SQL-like aggregates and θ is one of <, ≤, ≥, > . We propose a …

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Graphical Models Of Residue Coupling In Protein Families, John Thomas, Naren Ramakrishnan, Chris Bailey-Kellogg Mar 2005

Graphical Models Of Residue Coupling In Protein Families, John Thomas, Naren Ramakrishnan, Chris Bailey-Kellogg

Computer Science Technical Reports

Identifying residue coupling relationships within a protein family can provide important insights into intrinsic molecular processes, and has significant applications in modeling structure and dynamics, understanding function, and designing new or modified proteins. We present the first algorithm to infer an undirected graphical model representing residue coupling in protein families. Such a model serves as a compact description of the joint amino acid distribution, and can be used for predictive (will this newly designed protein be folded and functional?), diagnostic (why is this protein not stable or functional?), and abductive reasoning (what if I attempt to graft features of one …

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Video Text Detection And Segmentation For Optical Character Recognition, Chong-Wah Ngo, Chi-Kwong Chan Mar 2005

Video Text Detection And Segmentation For Optical Character Recognition, Chong-Wah Ngo, Chi-Kwong Chan

Research Collection School Of Computing and Information Systems

In this paper, we present approaches to detecting and segmenting text in videos. The proposed video-text-detection technique is capable of adaptively applying appropriate operators for video frames of different modalities by classifying the background complexities. Effective operators such as the repeated shifting operations are applied for the noise removal of images with high edge density. Meanwhile, a text-enhancement technique is used to highlight the text regions of low-contrast images. A coarse-to-fine projection technique is then employed to extract text lines from video frames. Experimental results indicate that the proposed text-detection approach is superior to the machine-learning-based (such as SVM and …

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An Analysis Of Biometric Technology As An Enabler To Information Assurance, Darren A. Deschaine Mar 2005

An Analysis Of Biometric Technology As An Enabler To Information Assurance, Darren A. Deschaine

Theses and Dissertations

The use of and dependence on, Information technology (IT) has grown tremendously in the last two decades. Still, some believe the United States is only in the infancy of this growth. This explosive growth has opened the door to capabilities that were only dreamed of in the past. As easy as it is to see how advantageous this technology is, it also is clear that with its advantages come distinct responsibilities and new problems that must be addressed. For instance, the minute one begins using information processing systems, the world of information assurance (IA) becomes far more complex. As a …

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Web Usability Guidelines For Air Force Knowledge Now Web Site, Gary A. Felax Mar 2005

Web Usability Guidelines For Air Force Knowledge Now Web Site, Gary A. Felax

Theses and Dissertations

The Department of Defense Net-Centric Data Strategies number one key attribute is to ensure data is visible, available, and usable when and where needed to accelerate decision-making. The Internet provides opportunities for quick and efficient disseminating of information to the public, distributing information throughout the Air Force, and accessing information from a variety of sources. In 2002, the Air Force CIO designated the Air Force Knowledge Now (AFKN) as the center of excellence for Knowledge Management. The site is a one-stop resource, providing access to a great depth and breadth of information. This study seeks to determine how usable and …

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Passwords: A Survey On Usage And Policy, Kurt W. Martinson Mar 2005

Passwords: A Survey On Usage And Policy, Kurt W. Martinson

Theses and Dissertations

Computer password use is on the rise. Passwords have become one of the primary authentication methods used today. It is because of their high use that organizations have started to place parameters on passwords. Are password restrictions a nuisance? What are some of the consequences that result as organizations place the burden of their computer security on passwords? This thesis analyzes the results of a survey instrument that was used to determine if individuals are using similar techniques or patterns when choosing or remembering their passwords. It also looks at how individuals feel about using passwords. In addition, the authors …

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Assessing The Usefulness Of Visualization Tools To Investigate Hidden Patterns With Insider Attack Cases, Amy M. Rammel Mar 2005

Assessing The Usefulness Of Visualization Tools To Investigate Hidden Patterns With Insider Attack Cases, Amy M. Rammel

Theses and Dissertations

The insider threat is a major concern for organizations. Open markets, technological advances, and the evolving definition of employee have exacerbated the insider threat. Insider threat research efforts are focusing on both prevention and detection techniques. However, recent security violation trends highlight the damage insider attacks cause organizations and illuminate why organizations and researchers must develop new approaches to this challenge. Although fruitful research is being conducted and new technologies are being applied to the insider threat problem, companies remain susceptible to the costly damage generated by insider threat actions. This research explored how visualization tools may be useful in …

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Modeling Information Quality Expectation In Unmanned Aerial Vehicle Swarm Sensor Databases, Patrick D. Baldwin Mar 2005

Modeling Information Quality Expectation In Unmanned Aerial Vehicle Swarm Sensor Databases, Patrick D. Baldwin

Theses and Dissertations

Swarming Unmanned Aerial Vehicles (UAVs) are the future of Intelligence, Surveillance and Reconnaissance (ISR). Swarms of hundreds of these vehicles, each equipped with multiple sensors, will one day fill the skies over hostile areas. As the sensors collect hundreds of gigabytes of data, telemetry data links will be unable to transmit the complete data picture to the ground in real time. The collected data will be stored on board the UAVs and selectively downloaded through queries issued from analysts on the ground. Analysts expect to find relevant sensor data within the collection of acquired sensor data. This expectation is not …

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Determination Of Structure From Motion Using Aerial Imagery, Paul R. Graham Mar 2005

Determination Of Structure From Motion Using Aerial Imagery, Paul R. Graham

Theses and Dissertations

The structure from motion process creates three-dimensional models from a sequence of images. Until recently, most research in this field has been restricted to land-based imagery. This research examines the current methods of land-based structure from motion and evaluates their performance for aerial imagery. Current structure from motion algorithms search the initial image for features to track though the subsequent images. These features are used to create point correspondences between the two images. The correspondences are used to estimate the motion of the camera and then the three-dimensional structure of the scene. This research tests current algorithms using synthetic data …

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Real-Time Mapping Using Stereoscopic Vision Optimization, Kevin M. Biggs Mar 2005

Real-Time Mapping Using Stereoscopic Vision Optimization, Kevin M. Biggs

Theses and Dissertations

This research focuses on efficient methods of generating 2D maps from stereo vision in real-time. Instead of attempting to locate edges between objects, we make the assumption that the representative surfaces of objects in a view provide enough information to generate a map while taking less time to locate during processing. Since all real-time vision processing endeavors are extremely computationally intensive, numerous optimization techniques are applied to allow for a real-time application: horizontal spike smoothing for post-disparity noise, masks to focus on close-proximity objects, melding for object synthesis, and rectangular fitting for object extraction under a planar assumption. Additionally, traditional …

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Robot Mapping With Real-Time Incremental Localization Using Expectation Maximization, Kevin L. Owens Mar 2005

Robot Mapping With Real-Time Incremental Localization Using Expectation Maximization, Kevin L. Owens

Theses and Dissertations

This research effort explores and develops a real-time sonar-based robot mapping and localization algorithm that provides pose correction within the context of a single room, to be combined with pre-existing global localization techniques, and thus produce a single, well-formed map of an unknown environment. Our algorithm implements an expectation maximization algorithm that is based on the notion of the alpha-beta functions of a Hidden Markov Model. It performs a forward alpha calculation as an integral component of the occupancy grid mapping procedure using local maps in place of a single global map, and a backward beta calculation that considers the …

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Assessing Information Trustability In A Secure Web Services Environment, Charles G. Penner Mar 2005

Assessing Information Trustability In A Secure Web Services Environment, Charles G. Penner

Theses and Dissertations

Decisions are made based on available information. A decision support system endeavors to provide information that is timely, accurate, and trustable. Information gathered from secure web service transactions has attributes that can be used to assess a level of trustability. The trust assessments enable a decision maker to determine a basis for confidence in the information presented from the web service. Existing trust assessment models do not provide a way to determine from a particular trust assessment what information attributes contributed to its computation. The present work creates trust values that retain and denote meaning, allowing a decision maker to …

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Scalability Via Summaries: Stream Query Processing Using Promising Tuples, M. H. Ali, Walid G. Aref, M. Y. Iltabakh Mar 2005

Scalability Via Summaries: Stream Query Processing Using Promising Tuples, M. H. Ali, Walid G. Aref, M. Y. Iltabakh

Department of Computer Science Technical Reports

No abstract provided.

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Efficient Join Processing Over Uncertain Data Technical Report, Reynold Cheng, Yuni Xia, Sunil Prabhakar, Rahul Shah, Jeffrey S. Vitter Mar 2005

Efficient Join Processing Over Uncertain Data Technical Report, Reynold Cheng, Yuni Xia, Sunil Prabhakar, Rahul Shah, Jeffrey S. Vitter

Department of Computer Science Technical Reports

No abstract provided.

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High Throughput Routing In Hybrid Cellular And Ad Hoc Networks, Ioannis Ioannidis, Bogdan Carbunar, Cristina Nita-Rotaru Mar 2005

High Throughput Routing In Hybrid Cellular And Ad Hoc Networks, Ioannis Ioannidis, Bogdan Carbunar, Cristina Nita-Rotaru

Department of Computer Science Technical Reports

No abstract provided.

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Secure Context-Sensitive Authorization, Kazuhiro Minami, David Kotz Mar 2005

Secure Context-Sensitive Authorization, Kazuhiro Minami, David Kotz

Dartmouth Scholarship

There is a recent trend toward rule-based authorization systems to achieve flexible security policies. Also, new sensing technologies in pervasive computing make it possible to define context-sensitive rules, such as “allow database access only to staff who are currently located in the main office.” However, these rules, or the facts that are needed to verify authority, often involve sensitive context information. This paper presents a secure context-sensitive authorization system that protects confidential information in facts or rules. Furthermore, our system allows multiple hosts in a distributed environment to perform the evaluation of an authorization query in a collaborative way; we …

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Policy-Driven Data Dissemination For Context-Aware Applications, Guanling Chen, David Kotz Mar 2005

Policy-Driven Data Dissemination For Context-Aware Applications, Guanling Chen, David Kotz

Dartmouth Scholarship

Context-aware pervasive-computing applications require continuous monitoring of their physical and computational environment to make appropriate adaptation decisions in time. The data streams produced by sensors, however, may overflow the queues on the dissemination path. Traditional flow-control and congestion-control policies either drop data or force the sender to pause. When the data sender is sensing the physical environment, however, a pause is equivalent to dropping data. Instead of arbitrarily dropping data that may contain important events, we present a policy-driven data dissemination service named PACK, based on an overlay-based infrastructure for efficient multicast delivery. PACK enforces application-specified policies that define how …

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Geocoder: An Efficient Backscatter Map Constructor, Luciano E. Fonseca, Brian R. Calder Mar 2005

Geocoder: An Efficient Backscatter Map Constructor, Luciano E. Fonseca, Brian R. Calder

Center for Coastal and Ocean Mapping

The acoustic backscatter acquired by multibeam and sidescan sonars carries important information about the seafloor morphology and physical properties, providing valuable data to aid the difficult task of seafloor characterization, and important auxiliary information for a bathymetric survey. One necessary step towards this characterization is the assemblage of more consistent and more accurate mosaics of acoustic backscatter. For that, it is necessary to radiometrically correct the backscatter intensities registered by these sonars, to geometrically correct and position each acoustic sample in a projection coordinate system and to interpolate properly the intensity values into a final backscatter map. Geocoder is a …

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Investigation Of Bottom Fishing Impacts On Benthic Structure Using Multibeam Sonar, Sidescan And Video, Mashkoor A. Malik, Larry A. Mayer Mar 2005

Investigation Of Bottom Fishing Impacts On Benthic Structure Using Multibeam Sonar, Sidescan And Video, Mashkoor A. Malik, Larry A. Mayer

Center for Coastal and Ocean Mapping

Bottom fishing gear is known to alter benthic structure, however changes in the shape of the sea floor are often too subtle to be detected by acoustic remote sensing. Nonetheless, long linear features were observed during a recent high-resolution multibeam sonar survey of Jeffreys Ledge, a prominent fishing ground in Gulf of Maine, located about 50 km from Portsmouth, NH. These marks, which have a relief of only few centimeters, are presumed to be caused by bottom dredging gear used in the area for scallop and clam fisheries. The extraction of these small features from a noisy data set (including …

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A Genetic Algorithm For Uav Routing Integrated With A Parallel Swarm Simulation, Matthew A. Russell Mar 2005

A Genetic Algorithm For Uav Routing Integrated With A Parallel Swarm Simulation, Matthew A. Russell

Theses and Dissertations

This research investigation addresses the problem of routing and simulating swarms of UAVs. Sorties are modeled as instantiations of the NP-Complete Vehicle Routing Problem, and this work uses genetic algorithms (GAs) to provide a fast and robust algorithm for a priori and dynamic routing applications. Swarms of UAVs are modeled based on extensions of Reynolds' swarm research and are simulated on a Beowulf cluster as a parallel computing application using the Synchronous Environment for Emulation and Discrete Event Simulation (SPEEDES). In a test suite, standard measures such as benchmark problems, best published results, and parallel metrics are used as performance …

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A Three Dimensional Helmet Mounted Primary Flight Reference For Paratroopers, Jason I. Thompson Mar 2005

A Three Dimensional Helmet Mounted Primary Flight Reference For Paratroopers, Jason I. Thompson

Theses and Dissertations

This thesis seeks to develop a Heads Up Display (HUD) presented on a Helmet Mounted Display (HMD), which presents a three-dimensional, graphical, predictive navigational reference to a paratrooper during a High Altitude, High Opening (HAHO) parachute jump. A Path Generating Algorithm (PGA) takes as input the Landing Zone's (LZ) location, the wind profile, and the paratrooper's parachute's performance characteristics, and returns a set of waypoints for the paratrooper to follow. The PGA attempts to maximize the distance that the paratrooper travels. The PGA's output is used to build a path to the LZ from a Release Point (RP). During the …

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Evaluation Of The Ad Hoc On-Demand Distance Vector Routing Protocol For Mobile Ad Hoc Networks, Amber J. Rickmon Mar 2005

Evaluation Of The Ad Hoc On-Demand Distance Vector Routing Protocol For Mobile Ad Hoc Networks, Amber J. Rickmon

Theses and Dissertations

Routing protocols designed for wired networks cannot be used in mobile ad hoc networks (MANETs) due to the dynamic topology, limited throughput, and energy constraints. New routing protocols have been designed for use in MANETs, but have not been thoroughly tested under realistic conditions such as node movement, number of sources, the presence of obstacles, and node speed. This research evaluates the performance of ad hoc on-demand distance vector routing with respect to throughput, goodput ratio, end-to-end (ETE) delay, node pair packet delivery rate, and node pair end-to-end delay. It shows these performance metrics vary significantly according to the choice …

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An Evolutionary Algorithm To Generate Ellipsoid Detectors For Negative Selection, Joseph M. Shapiro Mar 2005

An Evolutionary Algorithm To Generate Ellipsoid Detectors For Negative Selection, Joseph M. Shapiro

Theses and Dissertations

Negative selection is a process from the biological immune system that can be applied to two-class (self and nonself) classification problems. Negative selection uses only one class (self) for training, which results in detectors for the other class (nonself). This paradigm is especially useful for problems in which only one class is available for training, such as network intrusion detection. Previous work has investigated hyper-rectangles and hyper-spheres as geometric detectors. This work proposes ellipsoids as geometric detectors. First, the author establishes a mathematical model for ellipsoids. He develops an algorithm to generate ellipsoids by training on only one class of …

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Efficient Generation Of Social Network Data From Computer-Mediated Communication Logs, Jason Wei Sung Yee Mar 2005

Efficient Generation Of Social Network Data From Computer-Mediated Communication Logs, Jason Wei Sung Yee

Theses and Dissertations

The insider threat poses a significant risk to any network or information system. A general definition of the insider threat is an authorized user performing unauthorized actions, a broad definition with no specifications on severity or action. While limited research has been able to classify and detect insider threats, it is generally understood that insider attacks are planned, and that there is a time period in which the organization's leadership can intervene and prevent the attack. Previous studies have shown that the person's behavior will generally change, and it is possible that social network analysis could be used to observe …

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Accelerating Missile Threat Engagement Simulations Using Personal Computer Graphics Cards, Sean E. Jeffers Mar 2005

Accelerating Missile Threat Engagement Simulations Using Personal Computer Graphics Cards, Sean E. Jeffers

Theses and Dissertations

The 453rd Electronic Warfare Squadron supports on-going military operations by providing battlefield commanders with aircraft ingress and egress routes that minimize the risk of shoulder or ground-fired missile attacks on our aircraft. To determine these routes, the 453rd simulates engagements between ground-to-air missiles and allied aircraft to determine the probability of a successful attack. The simulations are computationally expensive, often requiring two-hours for a single 10-second missile engagement. Hundreds of simulations are needed to perform a complete risk assessment which includes evaluating the effectiveness of countermeasures such as flares, chaff, jammers, and missile warning systems. Thus, the need for faster …

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