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Threading And Autodocumenting News Videos: A Promising Solution To Rapidly Browse News Topics, Xiao Wu, Chong-Wah Ngo, Qing Li Mar 2006

Threading And Autodocumenting News Videos: A Promising Solution To Rapidly Browse News Topics, Xiao Wu, Chong-Wah Ngo, Qing Li

Research Collection School Of Computing and Information Systems

This paper describes the techniques in threading and autodocumenting news stories according to topic themes. Initially, we perform story clustering by exploiting the duality between stories and textual-visual concepts through a co-clustering algorithm. The dependency among stories of a topic is tracked by exploring the textual-visual novelty and redundancy of stories. A novel topic structure that chains the dependencies of stories is then presented to facilitate the fast navigation of the news topic. By pruning the peripheral and redundant news stories in the topic structure, a main thread is extracted for autodocumentary

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Robust Classification Of Eeg Signal For Brain-Computer Interface, Manoj Thulasidas, Cuntai Guan, Jiankang Wu Mar 2006

Robust Classification Of Eeg Signal For Brain-Computer Interface, Manoj Thulasidas, Cuntai Guan, Jiankang Wu

Research Collection School Of Computing and Information Systems

We report the implementation of a text input application (speller) based on the P300 event related potential. We obtain high accuracies by using an SVM classifier and a novel feature. These techniques enable us to maintain fast performance without sacrificing the accuracy, thus making the speller usable in an online mode. In order to further improve the usability, we perform various studies on the data with a view to minimizing the training time required. We present data collected from nine healthy subjects, along with the high accuracies (of the order of 95% or more) measured online. We show that the …

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Multiframe Shift Estimation, Stephen A. Bruckart Mar 2006

Multiframe Shift Estimation, Stephen A. Bruckart

Theses and Dissertations

The purpose of this research was to develop a fundamental framework for a new approach to multiframe translational shift estimation in image processing. This thesis sought to create a new multiframe shift estimator, to theoretically prove and experimentally test key properties of it, and to quantify its performance according to several metrics. The new estimator was modeled successfully and was proven to be an unbiased estimator under certain common image noise conditions. Furthermore its performance was shown to be superior to the cross correlation shift estimator, a robust estimator widely used in similar image processing cases, according to several criteria. …

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An Estimation Theory Approach To Detection And Ranging Of Obscured Targets In 3-D Ladar Data, Charles R. Burris Mar 2006

An Estimation Theory Approach To Detection And Ranging Of Obscured Targets In 3-D Ladar Data, Charles R. Burris

Theses and Dissertations

The purpose of this research is to develop an algorithm to detect obscured images in 3-D LADAR data. The real data used for this research was gathered using a FLASH LADAR system under development at AFRL/SNJM. The system transmits light with a wavelength of 1.55 micrometers and produces 20 128 X 128 temporally resolved images from the return pulse separated by less than 2 nanoseconds in time. New algorithms for estimating the range to a target in 3-D FLASH LADAR data were developed. Results from processing real data are presented and compared to the traditional correlation receiver for extracting ranges …

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Bda Enhancement Methodology Using Situational Parameter Adjustments, Michael V. Carras Jr. Mar 2006

Bda Enhancement Methodology Using Situational Parameter Adjustments, Michael V. Carras Jr.

Theses and Dissertations

In the context of close ground combat, the perception of Battle Damage Assessment (BDA) is closely linked with a soldier’s engagement decisions and has significant effects on the battlefield. Perceived BDA is also one of the most complex and uncertain processes facing the soldier in live combat. As a result, the modeling and simulation community has yet to adequately model the perceived BDA process in combat models. This research effort examines the BDA process from a perception standpoint and proposes a methodology to collect the pertinent data and model this perception in the Army’s current force-on-force model, CASTFOREM. A subject …

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An Adaptable Energy-Efficient Medium Access Control Protocol For Wireless Sensor Networks, Justin T. Kautz Mar 2006

An Adaptable Energy-Efficient Medium Access Control Protocol For Wireless Sensor Networks, Justin T. Kautz

Theses and Dissertations

Wireless networks have become ubiquitous recently and therefore their usefulness has also become more extensive. Wireless sensor networks (WSN) detect environmental information with sensors in remote settings. One problem facing WSNs is the inability to resupply power to these energy-constrained devices due to their remoteness. Therefore to extend a WSN's effectiveness, the lifetime of the network must be increased by making them as energy efficient as possible. An energy efficient medium access control (MAC) can boost a WSN's lifetime. This research creates a MAC protocol called Adaptive sensor Medium Access Control (AMAC) which is based on Sensor Medium Access Control …

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Flashlight: A Dynamic Detector Of Shared State, Race Conditions, And Locking Models In Concurrent Java Programs, Scott C. Hale Mar 2006

Flashlight: A Dynamic Detector Of Shared State, Race Conditions, And Locking Models In Concurrent Java Programs, Scott C. Hale

Theses and Dissertations

Concurrent Java programs are difficult to understand and implement correctly. This difficultly leads to code faults that are the source of many real-world reliability and security problems. Many factors contribute to concurrency faults in Java code; for example, programmers may not understand Java language semantics or, when using a Java library or framework, may not understand that their resulting program is concurrent. This thesis describes a dynamic analysis tool, named FlashLight, that detects shared state and possible race conditions within a program. FlashLight illuminates the concurrency within a program for programmers who are wholly or partially "in the dark" about …

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Evolving Self-Organized Behavior For Homogeneous And Heterogeneous Uav Or Ucav Swarms, Ian C. Price Mar 2006

Evolving Self-Organized Behavior For Homogeneous And Heterogeneous Uav Or Ucav Swarms, Ian C. Price

Theses and Dissertations

This investigation uses a self-organization (SO) approach to enable cooperative search and destruction of retaliating targets with swarms of homogeneous and heterogeneous unmanned aerial vehicles (UAVs). To facilitate specific system design, a facilitating SO algebraic framework is created that emphasizes scalability, robustness, and flexibility. This framework is then used to implement a UAV behavior architecture relying upon rules governing formation and target interaction. Sets of applicable behaviors are created by weighted summation of the rules where different weights act as distinct behavior archetypes. Appropriate behavior archetypes are based upon sense information distilled from the environment and a simple perceptron mapping. …

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Detecting Potential Insider Threats Through Email Datamining, James S. Okolica Mar 2006

Detecting Potential Insider Threats Through Email Datamining, James S. Okolica

Theses and Dissertations

No abstract provided.

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Metamorphism As A Software Protection For Non-Malicious Code, Thomas E. Dube Mar 2006

Metamorphism As A Software Protection For Non-Malicious Code, Thomas E. Dube

Theses and Dissertations

Most organizations are aware that threats from trusted insiders pose a great risk to their organization and are very difficult to protect against. Auditing is recognized as an effective technique to detect malicious insider activities. However, current auditing methods are typically applied with a one-size-fits-all approach and may not be an appropriate mitigation strategy, especially towards insider threats. This research develops a 4-step methodology for designing a customized auditing template for a Microsoft Windows XP operating system. Two tailoring methods are presented which evaluate both by category and by configuration. Also developed are various metrics and weighting factors as a …

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Cryptanalysis Of Pseudorandom Number Generators In Wireless Sensor Networks, Kevin M. Finnigin Mar 2006

Cryptanalysis Of Pseudorandom Number Generators In Wireless Sensor Networks, Kevin M. Finnigin

Theses and Dissertations

This work presents a brute-force attack on an elliptic curve cryptosystem implemented on UC Berkley's TinyOS operating system for wireless sensor networks. The attack exploits the short period of the pseudorandom number generator (PRNG) used by the cryptosystem to generate private keys. The attack assumes a laptop is listening promiscuously to network traffic for key messages and requires only the sensor node?s public key and network address to discover the private key. Experimental results show that roughly 50% of the address space leads to a private key compromise in 25 minutes on average. Furthermore, approximately 32% of the address space …

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A Real-Time Wireless Sensor Media Access Control (Mac) Protocol, Barry W. Park Mar 2006

A Real-Time Wireless Sensor Media Access Control (Mac) Protocol, Barry W. Park

Theses and Dissertations

Wireless sensor networks are rapidly becoming a platform for applications such as battlefield monitoring, intelligence gathering, environmental monitoring, and emergency response. Inherent in these applications is a priority and urgency of the information or messages. This means the messages must be delivered in a timely manner for them to be useful. This research assigns a message priority level and provides high-priority messages quicker access to the channel. Using MICA2 sensors and a modified Media Access Control (MAC) layer, real-time message End-to-End (ETE) delay was reduced by 50 percent. Coupled with this decrease in delay, these same real-time messages also had …

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Toward The Static Detection Of Deadlock In Java Software, Jose E. Fadul Mar 2006

Toward The Static Detection Of Deadlock In Java Software, Jose E. Fadul

Theses and Dissertations

Concurrency is the source of many real-world software reliability and security problems. Concurrency defects are difficult to detect because they defy conventional software testing techniques due to their non-local and non-deterministic nature. We focus on one important aspect of this problem: static detection of the possibility of deadlock - a situation in which two or more processes are prevented from continuing while each waits for resources to be freed by the continuation of the other. This thesis proposes a flow-insensitive interprocedural static analysis that detects the possibility that a program can deadlock at runtime. Our analysis proceeds in two steps. …

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Application Of Fuzzy State Aggregation And Policy Hill Climbing To Multi-Agent Systems In Stochastic Environments, Dean C. Wardell Mar 2006

Application Of Fuzzy State Aggregation And Policy Hill Climbing To Multi-Agent Systems In Stochastic Environments, Dean C. Wardell

Theses and Dissertations

Reinforcement learning is one of the more attractive machine learning technologies, due to its unsupervised learning structure and ability to continually even as the operating environment changes. Applying this learning to multiple cooperative software agents (a multi-agent system) not only allows each individual agent to learn from its own experience, but also opens up the opportunity for the individual agents to learn from the other agents in the system, thus accelerating the rate of learning. This research presents the novel use of fuzzy state aggregation, as the means of function approximation, combined with the policy hill climbing methods of Win …

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Verification Of A Decision Level Fusion Algorithm Using A Proven Atr System And Measured Sar Data, James Douglas Thompson Mar 2006

Verification Of A Decision Level Fusion Algorithm Using A Proven Atr System And Measured Sar Data, James Douglas Thompson

Theses and Dissertations

Decision level fusion (DLF) algorithms combine outputs of multiple single sensors to make one confident declaration of a target. This research compares performance results of a DLF algorithm using measured data and a proven ATR system with results from simulated data and a modeled ATR system. This comparison indicates that DLF offers significant performance improvements over single sensor looks. However, results based on simulated data and a modeled ATR are slightly optimistic and overestimate results from measured data and a proven ATR system by nearly 10% over all targets tested.

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A Comparison Of Main Rotor Smoothing Adjustments Using Linear And Neural Network Algorithms, Nathan A. Miller Mar 2006

A Comparison Of Main Rotor Smoothing Adjustments Using Linear And Neural Network Algorithms, Nathan A. Miller

Theses and Dissertations

Helicopter main rotor smoothing is a maintenance procedure that is routinely performed to minimize airframe vibrations induced by non-uniform mass and/or aerodynamic distributions in the main rotor system. This important task is both time consuming and expensive, so improvements to the process have long been sought. Traditionally, vibrations have been minimized by calculating adjustments based on an assumed linear relationship between adjustments and vibration response. In recent years, artificial neural networks have been trained to recognize non-linear mappings between adjustments and vibration response. This research was conducted in order observe the character of the adjustment mapping of the Vibration Management …

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Fortifying Password Authentication In Integrated Healthcare Delivery Systems, Yanjiang Yang, Robert H. Deng, Feng Bao Mar 2006

Fortifying Password Authentication In Integrated Healthcare Delivery Systems, Yanjiang Yang, Robert H. Deng, Feng Bao

Research Collection School Of Computing and Information Systems

Integrated Delivery Systems (IDSs) now become a primary means of care provision in healthcare domain. However, existing password systems (under either the single-server model or the multi-server model) do not provide adequate security when applied to IDSs. We are thus motivated to present a practical password authentication system built upon a novel two-server model. We generalize the two-server model to an architecture of a single control server supporting multiple service servers, tailored to the organizational structure of IDSs. The underlying user authentication and key exchange protocols we propose are password-only, neat, efficient, and robust against off-line dictionary attacks mounted by …

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Caps: Energy-Efficient Processing Of Continuous Aggregate Queries In Sensor Networks, Wen Hu, Archan Misra, Rajiv Shorey Mar 2006

Caps: Energy-Efficient Processing Of Continuous Aggregate Queries In Sensor Networks, Wen Hu, Archan Misra, Rajiv Shorey

Research Collection School Of Computing and Information Systems

In this paper, we design and evaluate an energy efficient data retrieval architecture for continuous aggregate queries in wireless sensor networks. We show how the modification of precision in one sensor affects the sample-reporting frequency of other sensors, and how the precisions of a group of sensors may be collectively modified to achieve the target quality of information (QoI) with higher energy-efficiency. The proposed collective adaptive precision setting (CAPS) architecture is then extended to exploit the observed temporal correlation among successive sensor samples for even greater energy efficiency. Detailed simulations with synthetic and real data traces demonstrate how the combination …

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Mitigating Distributed Denial Of Service Attacks In An Anonymous Routing Environment: Client Puzzles And Tor, Nicholas A. Fraser Mar 2006

Mitigating Distributed Denial Of Service Attacks In An Anonymous Routing Environment: Client Puzzles And Tor, Nicholas A. Fraser

Theses and Dissertations

Online intelligence operations use the Internet to gather information on the activities of U.S. adversaries. The security of these operations is paramount, and one way to avoid being linked to the Department of Defense (DoD) is to use anonymous communication systems. One such system, Tor, makes interactive TCP services anonymous. Tor uses the Transport Layer Security (TLS) protocol and is thus vulnerable to a distributed denial-of-service (DDoS) attack that can significantly delay data traversing the Tor network. This research uses client puzzles to mitigate TLS DDoS attacks. A novel puzzle protocol, the Memoryless Puzzle Protocol (MPP), is conceived, implemented, and …

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A Monocular Vision Based Approach To Flocking, Brian Kirchner Mar 2006

A Monocular Vision Based Approach To Flocking, Brian Kirchner

Theses and Dissertations

Flocking is seen in nature as a means for self protection, more efficient foraging, and other search behaviors. Although much research has been done regarding the application of this principle to autonomous vehicles, the majority of the research has relied on GPS information, broadcast communication, an omniscient central controller, or some other form of "global" knowledge. This approach, while effective, has serious drawbacks, especially regarding stealth, reliability, and biological grounding. This research effort uses three Pioneer P2-AT8 robots to achieve flocking behavior without the use of global knowledge. The sensory inputs are limited to two cameras, offset such that the …

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Publicly Verifiable Ownership Protection For Relational Databases, Yingjiu Li, Robert H. Deng Mar 2006

Publicly Verifiable Ownership Protection For Relational Databases, Yingjiu Li, Robert H. Deng

Research Collection School Of Computing and Information Systems

Today, watermarking techniques have been extended from the multimedia context to relational databases so as to protect the ownership of data even after the data are published or distributed. However, all existing watermarking schemes for relational databases are secret key based, thus require a secret key to be presented in proof of ownership. This means that the ownership can only be proven once to the public (e.g., to the court). After that, the secret key is known to the public and the embedded watermark can be easily destroyed by malicious users. Moreover, most of the existing techniques introduce distortions to …

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Velocal: A Web-Based Cycling Event Scheduler: A Web-Based Cycling Event Scheduler, Karl Olson Feb 2006

Velocal: A Web-Based Cycling Event Scheduler: A Web-Based Cycling Event Scheduler, Karl Olson

Regis University Student Publications (comprehensive collection)

This project focused on the creation of a web-based ride scheduling application for Cycling Friends of Fort Collins (CFFC). The CFFC is a recently organized non-competitive bicycling club founded with the purpose of facilitating rides of a variety of levels and encouraging cyclists to ride together. The primary goal of this application is to allow any user to schedule a group ride and send email notification and reminders of the event to all interested members. Individuals can then optionally respond with their attendance intentions. Providing an easy interface to schedule events will encourage more group rides and help foster a …

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Unix Remote Access Via Ibm S/390 System, Selena Pena Feb 2006

Unix Remote Access Via Ibm S/390 System, Selena Pena

Regis University Student Publications (comprehensive collection)

The MSCIT graduate program at Regis University offers UNIX and Information Assurance courses for all graduate students. In addition, the program gives students the opportunity to participate in the Systems Engineering and Application Development Practicum (SEAD) to complete their professional project/thesis. Due to the limited number of UNIX systems available, the graduate and SEAD students have a limited environment to work on. The UNIX and Information Assurance classes share the Acadunix UNIX server to complete lab work and homework assignments. Some students have limited root access via "sudo." Students cannot practice remote commands and can't use networking tools because another …

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Support For Xml Markup Of Image-Based Electronic Editions, Alex Dekhtyar, Ionut E. Iacob, Jerzy W. Jaromczyk, Kevin Kiernan, Neil Moore, Dorothy Carr Porter Feb 2006

Support For Xml Markup Of Image-Based Electronic Editions, Alex Dekhtyar, Ionut E. Iacob, Jerzy W. Jaromczyk, Kevin Kiernan, Neil Moore, Dorothy Carr Porter

Computer Science and Software Engineering

Image-based electronic editions enable researchers to view and study in an electronic environment historical manuscript images intricately linked to edition, transcript, glossary and apparatus files. Building image-based electronic editions poses a two-fold challenge. For humanities scholars, it is important to be able to use image and text to successfully encode the desired features of the manuscripts. Computer Scientists must find mechanisms for representing markup in its association both with the images, text and other auxiliary files and for making the representation available for efficient querying. This paper addresses the architecture of one such solution, that uses efficient data structures to …

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Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 22, Number 5, February 2006, College Of Engineering And Computer Science, Wright State University Feb 2006

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 22, Number 5, February 2006, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A six 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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Secure Context-Sensitive Authorization, Kazuhiro Minami Feb 2006

Secure Context-Sensitive Authorization, Kazuhiro Minami

Dartmouth College Ph.D Dissertations

Pervasive computing leads to an increased integration between the real world and the computational world, and many applications in pervasive computing adapt to the user's context, such as the location of the user and relevant devices, the presence of other people, light or sound conditions, or available network bandwidth, to meet a user's continuously changing requirements without taking explicit input from the users. We consider a class of applications that wish to consider a user's context when deciding whether to authorize a user's access to important physical or information resources. Such a context-sensitive authorization scheme is necessary when a mobile …

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Path Planning Algorithms Under The Link-Distance Metric, David Phillip Wagner Feb 2006

Path Planning Algorithms Under The Link-Distance Metric, David Phillip Wagner

Dartmouth College Ph.D Dissertations

The Traveling Salesman Problem and the Shortest Path Problem are famous problems in computer science which have been well studied when the objective is measured using the Euclidean distance. Here we examine these geometric problems under a different set of optimization criteria. Rather than considering the total distance traversed by a path, this thesis looks at reducing the number of times a turn is made along that path, or equivalently, at reducing the number of straight lines in the path. Minimizing this objective value, known as the link-distance, is useful in situations where continuing in a given direction is cheap, …

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Robust Parameter Synthesis For Planar Higher Pair Mechanical Systems, Min-Ho Kyung, Elisha Sacks Feb 2006

Robust Parameter Synthesis For Planar Higher Pair Mechanical Systems, Min-Ho Kyung, Elisha Sacks

Department of Computer Science Technical Reports

No abstract provided.

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Evaluation And Illustration Of A Free Software (Fs) Tool For Wireless Network Monitoring And Security, Victor A. Clincy, Krithi Sitaram Ajay Feb 2006

Evaluation And Illustration Of A Free Software (Fs) Tool For Wireless Network Monitoring And Security, Victor A. Clincy, Krithi Sitaram Ajay

Faculty Articles

Wireless communication provides users many benefits such as portability, flexibility, reduced hardware need and lower installation costs. Wireless local area networks (WLANs) for example allow users the ability to carry their laptops from place to place without any physical wires and without losing network connectivity.However, some amount of security risk is always associated with wireless networks. The most significant security risk for wireless technology is the potential outsiders have in gaining access to the communications medium, the communications medium being the air waves. Though WLANs provide the users with the option of roaming, this convenience is facilitated by broadcasting packets …

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Free Tools For Teaching & Researching Wireless Networking Concepts, Victor A. Clincy, Krithi Sitaram Ajay Feb 2006

Free Tools For Teaching & Researching Wireless Networking Concepts, Victor A. Clincy, Krithi Sitaram Ajay

Faculty Articles

As wireless networking and security become more prevalent in the market, more and more computer science programs are incorporating courses in wireless networks or at the least, devoting a significant percentage of the advanced networking courses to wireless topics. As a result, in addition to industry practitioners, there is a growing interest among university researchers and faculty regarding tools used for teaching and researching in wireless networking concepts.This tutorial will demonstrate two free tools, Network Stumbler and ITGuru's wireless module (academic version is free).

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