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2005

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Full-Text Articles in Computer Sciences

Department Of Computer Science Activity 1998-2004, David Kotz Mar 2005

Department Of Computer Science Activity 1998-2004, David Kotz

Computer Science Technical Reports

This report summarizes much of the research and teaching activity of the Department of Computer Science at Dartmouth College between late 1998 and late 2004. The material for this report was collected as part of the final report for NSF Institutional Infrastructure award EIA-9802068, which funded equipment and technical staff during that six-year period. This equipment and staff supported essentially all of the department's research activity during that period.

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A Statistical Performance Model Of Homogeneous Raidb Clusters, Brandon Lamar Rogers Mar 2005

A Statistical Performance Model Of Homogeneous Raidb Clusters, Brandon Lamar Rogers

Theses and Dissertations

The continual growth of the Internet and e-commerce is driving demand for speed, reliability and processing power. With the rapid development and maturation of e-commerce, the need for a quick access to large amounts of information is steadily rising. Traditionally, database systems have been used for information storage and retrieval. However, with online auctions, rapid Internet searches, and data archival, the need for more powerful database systems is also growing. One type of distributed database is called Redundant Arrays of Inexpensive Databases (RAIDb). RAIDb clusters are middleware-driven to promote interoperability and portability. RAIDb clusters allow for multiple levels of data …

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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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Rapid Delivery Of Massive Geospatial Data Over Internet2, Rollin Strohman, Michael Haungs Mar 2005

Rapid Delivery Of Massive Geospatial Data Over Internet2, Rollin Strohman, Michael Haungs

Computer Science and Software Engineering

We study the feasibility of the on-demand delivery of a massive geospatial dataset over Internet2 for educational use. The dataset (20TB uncompressed, 2.5TB compressed), generously made available for this study by AirphotoUSA, provides a seamless, one-meter resolution aerial orthophotograph covering over three million square miles of the continental United States. We identify factors that limit the scalability, availability and user-perceived performance of serving such a dataset. To do this, we conduct experiments that measure response times for various levels of network congestion, bandwidth, and load. We also provide a proof-of-concept experiment by serving the dataset over Internet2 to students at …

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Integrating And Delivering Massive Geospatial Datasets For Educational Use, Michael Haungs, Rollin Strohman Mar 2005

Integrating And Delivering Massive Geospatial Datasets For Educational Use, Michael Haungs, Rollin Strohman

Computer Science and Software Engineering

No abstract provided.

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A Translational Web Services Bridge Solution For Meaningful Interoperability Between Potentially Disparate Systems, Kym J. Pohl, Lakshmi Vempati, Jens G. Pohl Mar 2005

A Translational Web Services Bridge Solution For Meaningful Interoperability Between Potentially Disparate Systems, Kym J. Pohl, Lakshmi Vempati, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

An emerging issue in the world of context-centric software-based decision-support is the need for potentially disparate systems to interoperate in meaningful and useful ways. Such interoperability must go beyond the elementary communication of data and endeavor to support a more powerful context-oriented inter-system relationship. A key issue in such functionality is the support, moreover the promotion, of meaningful interoperability while still retaining individual system representations, or perspectives. In other words, the meaningful integration of potentially disparate systems in a manner that allows each collaborating system to retain its potentially unique means of representing, or perceiving, the domain over which it …

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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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Evaluation Of Mpeg-4 Ipmp Extension, Hwee Hwa Pang, Yongdong Wu Mar 2005

Evaluation Of Mpeg-4 Ipmp Extension, Hwee Hwa Pang, Yongdong Wu

Research Collection School Of Computing and Information Systems

MPEG-4 IPMPX (intellectual property management and protection extension) is the latest ISO standard which provides a flexible framework for protecting MPEG streams. The message mechanism of IPMPX enables interoperability among IPMPX-compliant devices no matter which protection methods are embedded. This paper highlights several problems in the message syntax of IPMPX: the tool delivery message IPMP_ToolES_AU is vulnerable to network attack, the authentication message IMP_Mutual_Authentication is incapable of defending against forgery attack, and the configuration message IPMP_SelectiveDecrptionInit is ambiguous and redundant. We propose a number of remedies to those problems, which can be incorporated into a corrigenda to improve the present …

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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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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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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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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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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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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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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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Analysis Of Effects Of Bgp Black Hole Routing On A Network Like The Niprnet, Michael D. Kleffman Mar 2005

Analysis Of Effects Of Bgp Black Hole Routing On A Network Like The Niprnet, Michael D. Kleffman

Theses and Dissertations

The Department of Defense (DoD) relies heavily on the Non-secure Internet Protocol Router Network (NIPRNET) to exchange information freely between departments, services, bases, posts, and ships. The NIPRNET is vulnerable to various attacks, to include physical and cyber attacks. One of the most frequently used cyber attacks by criminally motivated hackers is a Distributed Denial of Service (DDoS) attack. DDoS attacks can be used to exhaust network bandwidth and router processing capabilities, and as a leveraging tool for extortion. Border Gateway Protocol (BGP) black hole routing is a responsive defensive network technique for mitigating DDoS attacks. BGP black hole routing …

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An Analysis Of Perturbed Quantization Steganography In The Spatial Domain, Matthew D. Spisak Mar 2005

An Analysis Of Perturbed Quantization Steganography In The Spatial Domain, Matthew D. Spisak

Theses and Dissertations

Steganography is a form of secret communication in which a message is hidden into a harmless cover object, concealing the actual existence of the message. Due to the potential abuse by criminals and terrorists, much research has also gone into the field of steganalysis - the art of detecting and deciphering a hidden message. As many novel steganographic hiding algorithms become publicly known, researchers exploit these methods by finding statistical irregularities between clean digital images and images containing hidden data. This creates an on-going race between the two fields and requires constant countermeasures on the part of steganographers in order …

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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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National Security Agency (Nsa) Systems And Network Attack Center (Snac) Security Guides Versus Known Worms, Matthew W. Sullivan Mar 2005

National Security Agency (Nsa) Systems And Network Attack Center (Snac) Security Guides Versus Known Worms, Matthew W. Sullivan

Theses and Dissertations

Internet worms impact Internet security around the world even though there are many defenses to prevent the damage they inflict. The National Security Agency (NSA) Systems and Network Attack Center (SNAC) publishes in-depth configuration guides to protect networks from intrusion; however, the effectiveness of these guides in preventing the spread of worms hasn't been studied. This thesis establishes how well the NSA SNAC guides protect against various worms and exploits compared to Microsoft patches alone. It also identifies the aspects of the configuration guidance that is most effective in the absence of patches and updates, against network worm and e-mail …

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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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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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