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Physical Sciences and Mathematics Commons™

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2003

Brigham Young University

Computer Sciences

Articles 1 - 26 of 26

Full-Text Articles in Physical Sciences and Mathematics

A Study Of The Suitability Of Irobex For High-Speed Exchange Of Large Data Objects, Casey T. Deccio, Joseph Ekstrom, Charles D. Knutson, D. Ryan Partridge, Kevin B. Tew Dec 2003

A Study Of The Suitability Of Irobex For High-Speed Exchange Of Large Data Objects, Casey T. Deccio, Joseph Ekstrom, Charles D. Knutson, D. Ryan Partridge, Kevin B. Tew

Faculty Publications

This paper demonstrates that careful tuning of the OBEX and IrLAP negotiated parameters allows OBEX to scale well for use with large data objects and high transmission rates. Due to the substantial time overhead inherent in link turnarounds, minimizing turnarounds during the transmission of a large object helps to maximimize link efficiency. The IrLAP window size and OBEX packet size significantly impact the number of required turnarounds during the transmission of a large object. When these parameters are properly tuned, maximum throughput can be achieved, and OBEX performs efficiently at high data rates.

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Trust Negotiation For Authentication And Authorization In Healthcare Information Systems, Charles D. Knutson, Kent E. Seamons, Tore L. Sundelin, David K. Vawdrey Sep 2003

Trust Negotiation For Authentication And Authorization In Healthcare Information Systems, Charles D. Knutson, Kent E. Seamons, Tore L. Sundelin, David K. Vawdrey

Faculty Publications

The expanding availability of health information in an electronic format is strategic for industry-wide efforts to improve the quality and reduce the cnst of health care. The implementation of electronic medical record systems has been hindered by inadequate security provisions. This paper describes the use of frust negotiation as a framework for providing authentication and access control services in healthcare information systems. nust negotiation enables two parties with no pre-existing relationship to establish the trust necessary to perform sensitive transactions via the mutual disclosure of attributes contained within digital credentials. An extension of this system, surrogate irusf negoikiion is introduced …

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Schema Matching And Data Extraction Over Html Tables, Cui Tao Sep 2003

Schema Matching And Data Extraction Over Html Tables, Cui Tao

Theses and Dissertations

Data on the Web in HTML tables is mostly structured, but we usually do not know the structure in advance. Thus, we cannot directly query for data of interest. We propose a solution to this problem for the case of mostly structured data in the form of HTML tables, based on document-independent extraction ontologies. The solution entails elements of table location and table understanding, data integration, and wrapper creation. Table location and understanding allows us to locate the table of interest, recognize attributes and values, pair attributes with values, and form records. Data-integration techniques allow us to match source records …

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Target Sets: A Tool For Understanding And Predicting The Behavior Of Interacting Q-Learners, Nancy Fulda, Dan A. Ventura Sep 2003

Target Sets: A Tool For Understanding And Predicting The Behavior Of Interacting Q-Learners, Nancy Fulda, Dan A. Ventura

Faculty Publications

Reinforcement learning agents that interact in a common environment frequently affect each others’ perceived transition and reward distributions. This can result in convergence of the agents to a sub-optimal equilibrium or even to a solution that is not an equilibrium at all. Several modifications to the Q-learning algorithm have been proposed which enable agents to converge to optimal equilibria under specified conditions. This paper presents the concept of target sets as an aid to understanding why these modifications have been successful and as a tool to assist in the development of new modifications which are applicable in a wider range …

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Interactive Level-Set Smoothing For Photo Editing, Thomas C. Howard, Bryan S. Morse Sep 2003

Interactive Level-Set Smoothing For Photo Editing, Thomas C. Howard, Bryan S. Morse

Faculty Publications

This paper presents an interactive image-smoothing tool based on properties and manipulation of image level sets. This tool uses PDE-based level-set smoothing to preserve edge sharpness while smoothing noise and jagged contours. Unlike existing approaches using PDEs, the duration and areas of application are controlled interactively with immediate feedback to the user. Interaction issues are addressed, and parameters for adjusting the PDE are automatically estimated based on image characteristics.

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Modular Verification Of Timed Circuits Using Automatic Abstraction, Eric G. Mercer, Chris Myers, Hao Zheng Sep 2003

Modular Verification Of Timed Circuits Using Automatic Abstraction, Eric G. Mercer, Chris Myers, Hao Zheng

Faculty Publications

The major barrier that prevents the application of formal verification to large designs is state explosion. This paper presents a new approach for verification of timed circuits using automatic abstraction. This approach partitions the design into modules, each with constrained complexity. Before verification is applied to each individual module, irrelevant information to the behavior of the selected module is abstracted away. This approach converts a verification problem with big exponential complexity to a set of subproblems, each with small exponential complexity. Experimental results are promising in that they indicate that our approach has the potential of completing much faster while …

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Dynamic Sociometry In Particle Swarm Optimization, Mark Richards, Dan A. Ventura Sep 2003

Dynamic Sociometry In Particle Swarm Optimization, Mark Richards, Dan A. Ventura

Faculty Publications

The performance of Particle Swarm Optimization is greatly affected by the size and sociometry of the swarm. This research proposes a dynamic sociometry, which is shown to be more effective on some problems than the standard star and ring sociometries. The performance of various combinations of swarm size and sociometry on six different test functions is qualitatively analyzed.

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Just-In-Time Browsing For Digitized Microfilm And Other Similar Image Collections, William A. Barrett, Douglas J. Kennard Aug 2003

Just-In-Time Browsing For Digitized Microfilm And Other Similar Image Collections, William A. Barrett, Douglas J. Kennard

Faculty Publications

This paper describes “Just-In-Time Browsing” (JITB), a method for image browsing (at modem-like speed) in which image data is transmitted and presented to the user progressively, in prioritized order, based on image content and user interaction. Spatial resolution and grayscale or color fidelity is increased first for the portions of the image that are immediately of most interest to the user. JITB is specifically geared toward digitized microfilm and other similar document image collections, although it can also be used for other types of images. A series of common browsing tasks performed by multiple users demonstrates that JITB compares favorably …

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Consensus-Based Table Form Recognition, William A. Barrett, Heath E. Nielson Aug 2003

Consensus-Based Table Form Recognition, William A. Barrett, Heath E. Nielson

Faculty Publications

Zoning documents increases the resolution of indexing from the image level to the field level. A line-delimited tabular document forms a well defined series of regions. However, as image quality decreases, accurate zoning becomes increasingly difficult. Given a sequence of documents with the same layout, we present a robust zoning method which exploits both intra- and inter-document consensus to form a more accurate combined result (template) that can be applied to any other document with the same layout.

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Learning Real-Time A* Path Planner For Sensing Closely-Spaced Targets From An Aircraft, Jason K. Howlett, Michael A. Goodrich, Timothy W. Mclain Aug 2003

Learning Real-Time A* Path Planner For Sensing Closely-Spaced Targets From An Aircraft, Jason K. Howlett, Michael A. Goodrich, Timothy W. Mclain

Faculty Publications

This work develops an any-time path planner, based on the learning real-time A* (LRTA*) search, for generating flyable paths that allow an aircraft with a specified sensor footprint to sense a group of closely-spaced targets. The LRTA* algorithm searches a tree of flyable paths for the branch that accomplishes the desired objectives in the shortest distance. The tree of paths is created by assembling primitive turn and straight sections of a specified step size. The operating parameters for the LRTA* search directly influence the running time and path-length performance of the search. A modified LRTA* search is presented that terminates …

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T-Splines And T-Nurccs, Thomas W. Sederberg, Jianmin Zheng, Almaz Bakenov, Ahmad Nasri Jul 2003

T-Splines And T-Nurccs, Thomas W. Sederberg, Jianmin Zheng, Almaz Bakenov, Ahmad Nasri

Faculty Publications

This paper presents a generalization of non-uniform B-spline surfaces called T-splines. T-spline control grids permit T-junctions, so lines of control points need not traverse the entire control grid. T-splines support many valuable operations within a consistent framework, such as local refinement, and the merging of several B-spline surfaces that have different knot vectors into a single gap-free model. The paper focuses on T-splines of degree three, which are C2 (in the absence of multiple knots). T-NURCCs (Non-Uniform Rational Catmull-Clark Surfaces with T-junctions) are a superset of both T-splines and Catmull-Clark surfaces. Thus, a modeling program for T-NURCCs can handle any …

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A Self-Adapting Healthcare Information Infrastructure Using Mobile Computing Devices, James K. Archibald, Eric S. Hall, Charles D. Knutson, David K. Vawdrey Jun 2003

A Self-Adapting Healthcare Information Infrastructure Using Mobile Computing Devices, James K. Archibald, Eric S. Hall, Charles D. Knutson, David K. Vawdrey

Faculty Publications

Despite recent improvements in the gathering and sharing of patient medical information among healthcare providers, there remains a gap in the electronic medical record infrastructure. Patient data is not available in some situations, either because the infrastructure is inaccessible (as in a natural disaster) or because there is no way to link the patient to the infrastructure (e.g., the patient cannot supply necessary identification information). This paper describes the Poket Doktor System, an architecture that allows an individual to carry personal electronic medical information on a wireless handheld device such as a smart card, cell phone, or PDA. Medical workers …

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Dynamic Joint Action Perception For Q-Learning Agents, Nancy Fulda, Dan A. Ventura Jun 2003

Dynamic Joint Action Perception For Q-Learning Agents, Nancy Fulda, Dan A. Ventura

Faculty Publications

Q-learning is a reinforcement learning algorithm that learns expected utilities for state-action transitions through successive interactions with the environment. The algorithm's simplicity as well as its convergence properties have made it a popular algorithm for study. However, its non-parametric representation of utilities limits its effectiveness in environments with large amounts of perceptual input. For example, in multiagent systems, each agent may need to consider the action selections of its counterparts in order to learn effective behaviors. This creates a joint action space which grows exponentially with the number of agents in the system. In such situations, the Q-learning algorithm quickly …

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Knot Intervals And Multi-Degree Splines, Thomas W. Sederberg, Jianmin Zheng, Xiaowen Song May 2003

Knot Intervals And Multi-Degree Splines, Thomas W. Sederberg, Jianmin Zheng, Xiaowen Song

Faculty Publications

This paper studies the merits of using knot interval notation for B-spline curves, and presents formulae in terms of knot intervals for common B-spline operations such as knot insertion, differentiation, and degree elevation. Using knot interval notation, the paper introduces MD-splines, which are B-spline-like curves that are comprised of polynomial segments of various degrees (MD stands for \multi-degree"). MD-splines are a generalization of B-spline curves in that if all curve segments in an MD-spline have the same degree, it reduces to a B-spline curve. The paper focuses on MD-splines of degree 1, 2, and 3, as well as degree 1 …

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A Noise Filtering Method Using Neural Networks, Tony R. Martinez, Xinchuan Zeng May 2003

A Noise Filtering Method Using Neural Networks, Tony R. Martinez, Xinchuan Zeng

Faculty Publications

During the data collecting and labeling process it is possible for noise to be introduced into a data set. As a result, the quality of the data set degrades and experiments and inferences derived from the data set become less reliable. In this paper we present an algorithm, called ANR (automatic noise reduction), as a filtering mechanism to identify and remove noisy data items whose classes have been mislabeled. The underlying mechanism behind ANR is based on a framework of multi-layer artificial neural networks. ANR assigns each data item a soft class label in the form of a class probability …

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Simplifying Ocr Neural Networks With Oracle Learning, Tony R. Martinez, Joshua Menke May 2003

Simplifying Ocr Neural Networks With Oracle Learning, Tony R. Martinez, Joshua Menke

Faculty Publications

Often the best model to solve a real world problem is relatively complex. The following presents oracle learning, a method using a larger model as an oracle to train a smaller model on unlabeled data in order to obtain (1) a simpler acceptable model and (2) improved results over standard training methods on a similarly sized smaller model. In particular, this paper looks at oracle learning as applied to multi-layer perceptrons trained using standard backpropagation. For optical character recognition, oracle learning results in an 11.40% average decrease in error over direct training while maintaining 98.95% of the initial oracle accuracy.

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Model-Based Human-Centered Task Automation: A Case Study In Acc System Design, Michael A. Goodrich, Erwin R. Boer May 2003

Model-Based Human-Centered Task Automation: A Case Study In Acc System Design, Michael A. Goodrich, Erwin R. Boer

Faculty Publications

Engineers, business managers, and governments are increasingly aware of the importance and difficulty of integrating technology and humans. The presence of technology can enhance human comfort, efficiency, and safety, but the absence of human factors analysis can lead to uncomfortable, inefficient, and unsafe systems. Systematic human-centered design requires a basic understanding of how humans generate and manage tasks. A very useful model of human behavior generation can be obtained by recognizing the task-specific role of mental models in not only guiding execution of skills but also managing initiation and termination of these skills. By identifying the human operator’s mental models …

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Enabling Remote Access To Personal Electronic Medical Records, James K. Archibald, Eric S. Hall, Charles D. Knutson, David K. Vawdrey May 2003

Enabling Remote Access To Personal Electronic Medical Records, James K. Archibald, Eric S. Hall, Charles D. Knutson, David K. Vawdrey

Faculty Publications

Millions of people suffer from medical conditions that should be made known to healthcare practitioners prior to treatment. Paramedics and emergency room doctors cannot provide optimal care without sufficient knowledge of a patient’s medical history. Lacking patient information such as allergies, current prescriptions, and preexisting conditions, medical professionals are often forced to either delay treatment or rely on instincts. Medical mistakes in situations like these kill thousands of people and cost an estimated US$37 billion each year in the United States [1]. With the advent of electronic medical records (EMRs), patient information can be stored in computer databases at hospitals …

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Concurrently Learning Neural Nets: Encouraging Optimal Behavior In Cooperative Reinforcement Learning Systems, Nancy Fulda, Dan A. Ventura May 2003

Concurrently Learning Neural Nets: Encouraging Optimal Behavior In Cooperative Reinforcement Learning Systems, Nancy Fulda, Dan A. Ventura

Faculty Publications

Reinforcement learning agents interacting in a common environment often fail to converge to optimal system behaviors even when the individual goals of the agents are fully compatible. Claus and Boutilier have demonstrated that the use of joint action learning helps to overcome these difficulties for Q-learning systems. This paper studies an application of joint action learning to systems of neural networks. Neural networks are a desirable candidate for such augmentations for two reasons: (1) they may be able to generalize more effectively than Q-learners, and (2) the network topology used may improve the scalability of joint action learning to systems …

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Protecting Sensitive Credential Content During Trust Negotiation, Ryan D. Jarvis Apr 2003

Protecting Sensitive Credential Content During Trust Negotiation, Ryan D. Jarvis

Theses and Dissertations

Keeping sensitive information private in a public world is a common concern to users of digital credentials. A digital credential may contain sensitive attributes certifying characteristics about its owner. X.509v3, the most widely used certificate standard, includes support for certificate extensions that make it possible to bind multiple attributes to a public key contained in the certificate. This feature, although convenient, potentially exploits the certificate holder's private information contained in the certificate. There are currently no privacy considerations in place to protect the disclosure of attributes in a certificate. This thesis focuses on protecting sensitive credential content during trust negotiation …

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Transport Discovery In Wireless Multi-Transport Environments, Shannon B. Barnes, Charles D. Knutson, Ryan W. Woodings Mar 2003

Transport Discovery In Wireless Multi-Transport Environments, Shannon B. Barnes, Charles D. Knutson, Ryan W. Woodings

Faculty Publications

In order to utilize multiple transports, devices must discover common mechanisms for communication, a procedure we call Multi-Transport Discovery. The Multi-Transport Discovery algorithm presented in this paper is a four-phase procedure (Transport Probing, Transport Querying, Address-to-Device Mapping, and Transport Accessibility) that can discover common transports within a multi-transport environment. Transport Probing uses a transport-dependent device discovery mechanism to discover an initial link. Transport Querying communicates over the probed link to query additional transports. Address-to-Device Mapping correctly correlates each transport to a remote device. Finally, Transport Accessibility periodically ascertains link availability during an application session.

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Inverse Multiplexing In Short-Range Multi-Transport Wireless Communications, Lichen Dai, Heidi R. Duffin, James C. Funk, Charles D. Knutson Mar 2003

Inverse Multiplexing In Short-Range Multi-Transport Wireless Communications, Lichen Dai, Heidi R. Duffin, James C. Funk, Charles D. Knutson

Faculty Publications

This paper describes a mechanism for utilizing Inverse Multiplexing to significantly increase the bandwidth available to short-range wireless devices. Previous work with Inverse Multiplexing has focused on wired networks; its implementation with short-range wireless transports introduces heterogeneity in the links, which must be taken into account. A mathematical model for an Inverse Multiplexing system is derived for several scheduling algorithms. Both Process Limited and Transport Limited systems are examined. The validity of this model is shown by our implementation of an Inverse Multiplexing layer that uses IrDA and Bluetooth transports. Concepts related to Inverse Multiplexing such as usage models, negotiation, …

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Gaussian And Mean Curvatures Of Rational Bézier Patches, Thomas W. Sederberg, Jianmin Zheng Mar 2003

Gaussian And Mean Curvatures Of Rational Bézier Patches, Thomas W. Sederberg, Jianmin Zheng

Faculty Publications

This note derives formulae for Gaussian and mean curvatures for tensor-product and triangular rational Bézier patches in terms of the respective control meshes. These formulae provide more geometric intuition than the generic formulae from differential geometry.

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Ontology-Based Extraction Of Rdf Data From The World Wide Web, Timothy Adam Chartrand Mar 2003

Ontology-Based Extraction Of Rdf Data From The World Wide Web, Timothy Adam Chartrand

Theses and Dissertations

The simplicity and proliferation of the World Wide Web (WWW) has taken the availability of information to an unprecedented level. The next generation of the Web, the Semantic Web, seeks to make information more usable by machines by introducing a more rigorous structure based on ontologies. One hinderance to the Semantic Web is the lack of existing semantically marked-up data. Until there is a critical mass of Semantic Web data, few people will develop and use Semantic Web applications. This project helps promote the Semantic Web by providing content. We apply existing information-extraction techniques, in particular, the BYU ontologybased data-extraction …

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Metrics For Evaluating Human-Robot Interactions, Michael A. Goodrich, Dan R. Olsen Jr. Jan 2003

Metrics For Evaluating Human-Robot Interactions, Michael A. Goodrich, Dan R. Olsen Jr.

Faculty Publications

Metrics for evaluating the quality of a human-robot interface are introduced. The autonomy of a robot is measured by its neglect time. The robot attention demand metric measures how much of the user’s attention is involved with instructing a robot. The free-time and fan-out metrics are two ways to measure this demand. Each of them leads to estimates of the interaction effort. Reducing interaction effort without diminishing task effectiveness is the goal of human-robot interaction design.

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A Memory-Based Approach To Cantonese Tone Recognition, Deryle W. Lonsdale, Michael Emonts Jan 2003

A Memory-Based Approach To Cantonese Tone Recognition, Deryle W. Lonsdale, Michael Emonts

Faculty Publications

This paper introduces memory-based learning as a viable approach for Cantonese tone recognition. The memorybased learning algorithm employed here outperforms other documented current approaches for this problem, which is based on neural networks. Various numbers of tones and features are modeled to find the best method for feature selection and extraction. To further optimize this approach, experiments are performed to isolate the best feature weighting method, the best class voting weights method, and the best number of k-values to implement. Results and possible future work are discussed.

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