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Articles 2551 - 2580 of 3436

Full-Text Articles in Physical Sciences and Mathematics

The Origins Of Four Paterae Of Malea Planum, Mars, Susan K. Larson Mar 2007

The Origins Of Four Paterae Of Malea Planum, Mars, Susan K. Larson

Theses and Dissertations

Malea Planum is a volcanic plain on the southern rim of Hellas Planitia, the largest impact basin on Mars. Four large circular structures on Malea Planum have traditionally been identified as paterae, or low relief, central vent volcanoes (Plescia and Saunders, 1979). A geologic map was constructed and new crater counts made to explore the ages and origins of the paterae. Amphitrites and Peneus Paterae have radial patterns of wrinkle ridges on their flanks and distinct summit calderas (95 km and 130 km across) with arcuate bounding scarps. In contrast, Malea and Pityusa Paterae are broad depressions with diameters greater …

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Improving Machine Learning Through Oracle Learning, Joshua Ephraim Menke Mar 2007

Improving Machine Learning Through Oracle Learning, Joshua Ephraim Menke

Theses and Dissertations

The following dissertation presents a new paradigm for improving the training of machine learning algorithms, oracle learning. The main idea in oracle learning is that instead of training directly on a set of data, a learning model is trained to approximate a given oracle's behavior on a set of data. This can be beneficial in situations where it is easier to obtain an oracle than it is to use it at application time. It is shown that oracle learning can be applied to more effectively reduce the size of artificial neural networks, to more efficiently take advantage of domain experts …

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Ria: An Rf Interference Avoidance Algorithm For Heterogeneous Wireless Networks, Daniel P. Delorey, Qiuyi Duan, Charles D. Knutson, Manoj Pandey, Lei Wang, Ryan W. Woodings, Daniel Zappala Mar 2007

Ria: An Rf Interference Avoidance Algorithm For Heterogeneous Wireless Networks, Daniel P. Delorey, Qiuyi Duan, Charles D. Knutson, Manoj Pandey, Lei Wang, Ryan W. Woodings, Daniel Zappala

Faculty Publications

Devices with multiple wireless interfaces are becoming increasingly popular. We envision that these devices will become the building block for future mesh networks, providing seamless connectivity across a range of heterogeneous devices. Although these devices typically implement frequency sharing, using either Direct Sequence Spread Spectrum (DSSS) or Frequency Hopping Spread Spectrum (FHSS), they may still interfere with one another. In this paper we provide a novel Radio Interference Avoidance (RIA) algorithm that solves the problem of interference between IEEE 802.11 and Bluetooth. We then extend this algorithm to other types of DSSS and FHSS combinations. Though the algorithm is limited …

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Pyridinium Bis-Retinoids: Extraction, Synthesis, And Folate Coupling, Mary Allison Alvarez Mar 2007

Pyridinium Bis-Retinoids: Extraction, Synthesis, And Folate Coupling, Mary Allison Alvarez

Theses and Dissertations

This thesis is divided into two parts.Part I describes the organic extraction, separation, and liquid chromatographic-mass spectrometric analysis of chromophores from human and bovine retinal pigment epithelium. Flurorophores in the retinal pigment epithelium have been implicated in age related macular degeneration. In addition, the synthesis and characterization of a number of bis-retinoid type compounds that may potentially be found in such extracts, or that may be used for insight into pyridinium bis-retinoid reactivity, was accomplished.Part II describes a study of pyridinium bis-retinoid-folic acid coupling with respect to linker type, linker length, and nature of the linkage. Folic acid has been …

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Obstacle Annotation By Demonstration, Michael David Clement Mar 2007

Obstacle Annotation By Demonstration, Michael David Clement

Theses and Dissertations

By observing human driving with a “digital head" (combined video camera and accelerometers) and taking a few hand annotations, we can automatically annotate regions in a robot's field of view that should be interpreted as obstacles to be avoided. This is accomplished by detecting the movement for a given frame in a video. Some hand annotations of video frames are necessary and they are used to create Probability Grids. Using the movement data and the Probability Grids, it is possible to annotate large amounts of video data quickly in an automated system.

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The Effect Of Birth Order On Infant Injury, Heather L. Van Duker Mar 2007

The Effect Of Birth Order On Infant Injury, Heather L. Van Duker

Theses and Dissertations

Pediatric injury is both common and expensive. Finding ways to prevent pediatric injury is a major public health concern. Many studies have investigated various aspects of pediatric injury, and some suggest that birth order may be an important risk factor for pediatric injury. This study further examined the relationship of birth order with pediatric injury, specifically studying the association of birth order with emergency department-attended infant injury while adjusting for other important family and individual covariates. Data for analysis included Utah birth certificate, death certificate, and hospital emergency department datasets, which were probabilistically linked to obtain complete demographic and injury …

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Grating Lobe Reduction In Transducer Arrays Through Structural Filtering Of Supercritical Plates, Brian E. Anderson, Stephen A. Hambric, Jack W. Hughes Mar 2007

Grating Lobe Reduction In Transducer Arrays Through Structural Filtering Of Supercritical Plates, Brian E. Anderson, Stephen A. Hambric, Jack W. Hughes

Faculty Publications

The effect of placing a structural acoustic filter between water and the transducer elements of an array to help reduce undesirable grating lobes is investigated. A supercritical plate is mounted to transducer elements with a thin decoupling polyurethane layer between the transducers and the plate. The plate acts as a radiation/incidence angle filter to pass energy at angles near normal incidence, but suppress energy at large incidence angles. Grating lobe reduction is achieved at the expense of limiting the available steering of the main lobe. Within this steer angle limitation, the main lobe can be steered as normal while the …

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Observational Studies Of Software Engineering Using Data From Software Repositories, Daniel Pierce Delorey Mar 2007

Observational Studies Of Software Engineering Using Data From Software Repositories, Daniel Pierce Delorey

Theses and Dissertations

Data for empirical studies of software engineering can be difficult to obtain. Extrapolations from small controlled experiments to large development environments are tenuous and observation tends to change the behavior of the subjects. In this thesis we propose the use of data gathered from software repositories in observational studies of software engineering. We present tools we have developed to extract data from CVS repositories and the SourceForge Research Archive. We use these tools to gather data from 9,999 Open Source projects. By analyzing these data we are able to provide insights into the structure of Open Source projects. For example, …

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Development Of An H-Alpha Index For The Detection Of Pms Candidates In Young Open Clusters, Liberty Rae Evanko Mar 2007

Development Of An H-Alpha Index For The Detection Of Pms Candidates In Young Open Clusters, Liberty Rae Evanko

Theses and Dissertations

One phase of formation of medium- and low-mass stars is the optically visible phase known as the pre-main-sequence or PMS phase. In order to further the understanding of this phase, more of these PMS objects need to be identified and classified. Previous techniques have used photometry to identify possible PMS objects by their characteristic Hα emission. Once identified these objects can be studied spectroscopically yielding complete PMS classification. This study develops a method to locate these emission objects that overcomes two limitations of previous techniques. The first limitation is the need for the creation of reddening maps. It is eliminated …

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Stylized Hatching For 3d Animation, Trent Fielding Crow Mar 2007

Stylized Hatching For 3d Animation, Trent Fielding Crow

Theses and Dissertations

Much research has been done in creating non-photorealistic renderings of objects that mimic the look of hand-made drawings by traditional artists. This thesis extends work in this area by presenting an NPR hatching method that can be applied to 3D animated films to help them feel more hand drawn. In contrast to most other NPR methods, this method preserves the 3D lighting and effects of the film that make it interesting to watch. This process includes a procedural algorithm to create a hatching pattern that can be easily integrated into any film's pipeline that uses Renderman. In addition, we create …

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Bounds And Conditions: A Kolob In Our Solar System?, David D. Allred Mar 2007

Bounds And Conditions: A Kolob In Our Solar System?, David D. Allred

Faculty Publications

In 2003, Dialogue ran adjacent essays by two scientists, David Tolman and David Allred. The two Davids had been students together at Princeton, attending the same student ward. Decades after Princeton, Tolman had left Mormonism and Allred had stayed. Their essays are a fascinating juxtaposition. In the course of his piece, David Allred ventured for a few paragraphs into a discussion of the planet Jupiter and its role as a governor and protector in our solar system—a type of Kolob. Although the other author dismissed the topic as “fanciful physics,” my own interest was piqued. I asked Dr. Allred, who …

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Graphical And Bayesian Analysis Of Unbalanced Patient Management Data, Emily Stewart Righter Mar 2007

Graphical And Bayesian Analysis Of Unbalanced Patient Management Data, Emily Stewart Righter

Theses and Dissertations

The International Normalizing Ratio (INR) measures the speed at which blood clots. Healthy people have an INR of about one. Some people are at greater risk of blood clots and their physician prescribes a target INR range, generally 2-3. The farther a patient is above or below their prescribed range, the more dangerous their situation. A variety of point-of-care (POC) devices has been developed to monitor patients. The purpose of this research was to develop innovative graphics to help describe a highly unbalanced dataset and to carry out Bayesian analyses to determine which of five devices best manages patients. An …

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Live Surface, Christopher J. Armstrong Feb 2007

Live Surface, Christopher J. Armstrong

Theses and Dissertations

Live Surface allows users to segment and render complex surfaces from 3D image volumes at interactive (sub-second) rates using a novel, Cascading Graph Cut (CGC). Live Surface consists of two phases. (1) Preprocessing for generation of a complete 3D watershed hierarchy followed by tracking of all catchment basin surfaces. (2) User interaction in which, with each mouse movement, the 3D object is selected and rendered in real time. Real-time segmentation is ccomplished by cascading through the 3D watershed hierarchy from the top, applying graph cut successively at each level only to catchment basins bordering the segmented surface from the previous …

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A Coarse Grain Model For Dna, Thomas A. Knotts Iv, Nitin Rathore, David C. Schwartz, Juan J. De Pablo Feb 2007

A Coarse Grain Model For Dna, Thomas A. Knotts Iv, Nitin Rathore, David C. Schwartz, Juan J. De Pablo

Faculty Publications

Understanding the behavior of DNA at the molecular level is of considerable fundamental and engineering importance. While adequate representations of DNA exist at the atomic and continuum level, there is a relative lack of models capable of describing the behavior of DNA at mesoscopic length scales. We present a mesoscale model of DNA that reduces the complexity of a nucleotide to three interactions sites, one each for the phosphate, sugar, and base, thereby rendering the investigation of DNA up to a few microns in length computationally tractable. The charges on these sites are considered explicitly. The model is parametrized using …

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Analysis Using Smoothing Via Penalized Splines As Implemented In Lme() In R, John R. Howell Feb 2007

Analysis Using Smoothing Via Penalized Splines As Implemented In Lme() In R, John R. Howell

Theses and Dissertations

Spline smoothers as implemented in common mixed model software provide a familiar framework for estimating semi-parametric and non-parametric models. Following a review of literature on splines and mixed models, details for implementing mixed model splines are presented. The examples use an experiment in the health sciences to demonstrate how to use mixed models to generate the smoothers. The first example takes a simple one-group case, while the second example fits an expanded model using three groups simultaneously. The second example also demonstrates how to fit confidence bands to the three-group model. The examples use mixed model software as implemented in …

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Feature-Based Mini Unmanned Air Vehicle Video Euclidean Stabilization With Local Mosaics, Damon Dyck Gerhardt Feb 2007

Feature-Based Mini Unmanned Air Vehicle Video Euclidean Stabilization With Local Mosaics, Damon Dyck Gerhardt

Theses and Dissertations

Video acquired using a camera mounted on a mini Unmanned Air Vehicle (mUAV) may be very helpful in Wilderness Search and Rescue and many other applications but is commonly plagued with limited spatial and temporal field of views, distractive jittery motions, disorienting rotations, and noisy and distorted images. These problems collectively make it very difficult for human viewers to identify objects of interest as well as infer correct orientations throughout the video. In order to expand the temporal and spatial field of view, stabilize, and better orient users of noisy and distorted mUAV video, a method is proposed of estimating …

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Human–Robot Interaction: A Survey, Michael A. Goodrich, Alan C. Schultz Feb 2007

Human–Robot Interaction: A Survey, Michael A. Goodrich, Alan C. Schultz

Faculty Publications

Human–Robot Interaction (HRI) has recently received considerable attention in the academic community, in labs, in technology companies, and through the media. Because of this attention, it is desirable to present a survey of HRI to serve as a tutorial to people outside the field and to promote discussion of a unified vision of HRI within the field. The goal of this review is to present a unified treatment of HRI-related problems, to identify key themes, and discuss challenge problems that are likely to shape the field in the near future. Although the review follows a survey structure, the goal of …

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Interactive Image Repair With Assisted Structure And Texture Completion, Teryl Arnold, Bryan S. Morse Feb 2007

Interactive Image Repair With Assisted Structure And Texture Completion, Teryl Arnold, Bryan S. Morse

Faculty Publications

Removing image defects in an undetectable manner has been studied for its many useful and varied applications. In many cases the desired result may be ambiguous from the image data alone and needs to be guided by a user’s knowledge of the intended result. This paper presents a framework for interactively incorporating user guidance into the filling-in process, more effectively using user input to fill in damaged regions in an image. This framework contains five main steps: first, the scratch or defect is detected; second, the edges outside the defect are detected; third, curves are fit to the detected edges; …

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Performance Evaluation Of Vision-Based Navigation And Landing On A Rotorcraft Unmanned Aerial Vehicle, David Hubbard, Timothy W. Mclain, Bryan S. Morse, Colin Theodore, Mark Tischler Feb 2007

Performance Evaluation Of Vision-Based Navigation And Landing On A Rotorcraft Unmanned Aerial Vehicle, David Hubbard, Timothy W. Mclain, Bryan S. Morse, Colin Theodore, Mark Tischler

Faculty Publications

A Rotorcraft UAV provides an ideal experimental platform for vision-based navigation. This paper describes the flight tests of the US Army PALACE project, which implements Moravec’s pseudo-normalized correlation tracking algorithm. The tracker uses the movement of the landing site in the camera, a laser range, and the aircraft attitude from an IMU to estimate the relative motion of the UAV. The position estimate functions as a GPS equivalent to enable the rotorcraft to maneuver without the aid of GPS. With GPS data as a baseline, tests were performed in simulation and in flight that measure the accuracy of the position …

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Selecting The Best Linear Mixed Model Using Predictive Approaches, Jun Wang Jan 2007

Selecting The Best Linear Mixed Model Using Predictive Approaches, Jun Wang

Theses and Dissertations

The linear mixed model is widely implemented in the analysis of longitudinal data. Inference techniques and information criteria are available and well-studied for goodness-of-fit within the linear mixed model setting. Predictive approaches such as R-squared, PRESS, and CCC are available for the linear mixed model but require more research (Edward, 2005). This project used simulation to investigate the performance of R-squared, PRESS, CCC, Pseudo F-test and information criterion for goodness-of-fit within the linear mixed model framework. Marginal and conditional approaches for these predictive statistics were studied under different variance-covariance structures. For compound symmetry structure, the success rates for all 17 …

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Banda Forearc Metamorphic Rocks Accreted To The Australian Continental Margin: Detailed Analysis Of The Lolotoi Complex Of East Timor, Carl Eldon Standley Jan 2007

Banda Forearc Metamorphic Rocks Accreted To The Australian Continental Margin: Detailed Analysis Of The Lolotoi Complex Of East Timor, Carl Eldon Standley

Theses and Dissertations

Petrologic, structural and age investigations of the Lolotoi Complex of East Timor indicate that it is part of a group of thin metamorphic klippen found throughout the region that were detached from the Banda forearc and accreted to the NW Australian continental margin during Late Miocene to Present arc-continent collision. Metamorphic rock types are dominated by (in order of greatest to least abundance), greenschist, graphitic phyllite, quartz-mica schist, amphibolite and pelitic schist. Mineral, whole rock, and trace element geochemical analyses of metabasites indicate that protolith compositions are consistent with tholeiitic basalt and basaltic andesite with mixed MORB and oceanic arc …

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System For Collision Detection Between Deformable Models Built On Axis Aligned Bounding Boxes And Gpu Based Culling, David Owen Tuft Jan 2007

System For Collision Detection Between Deformable Models Built On Axis Aligned Bounding Boxes And Gpu Based Culling, David Owen Tuft

Theses and Dissertations

Collision detection between deforming models is a difficult problem for collision detection systems to handle. This problem is even more difficult when deformations are unconstrained, objects are in close proximity to one another, and when the entity count is high. We propose a method to perform collision detection between multiple deforming objects with unconstrained deformations that will give good results in close proximities. Currently no systems exist that achieve good performance on both unconstrained triangle level deformations and deformations that preserve edge connectivity. We propose a new system built as a combination of Graphics Processing Unit (GPU) based culling and …

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Eliminating Redundant And Less-Informative Rss News Articles Based On Word Similarity And A Fuzzy Equivalence Relation, Ian Garcia Jan 2007

Eliminating Redundant And Less-Informative Rss News Articles Based On Word Similarity And A Fuzzy Equivalence Relation, Ian Garcia

Theses and Dissertations

The Internet has marked this era as the information age. There is no precedent in the amazing amount of information, especially network news, that can be accessed by Internet users these days. As a result, the problem of seeking information in online news articles is not the lack of them but being overwhelmed by them. This brings huge challenges regarding processing of online news feeds, i.e., how to determine which news article is important, how to determine the quality of each news article, and how to filter irrelevant and redundant information. In this thesis, we propose a method for filtering …

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Implicit Affinity Networks, Matthew Scott Smith Jan 2007

Implicit Affinity Networks, Matthew Scott Smith

Theses and Dissertations

Although they clearly exist, affinities among individuals are not all easily identified. Yet, they offer unique opportunities to discover new social networks, strengthen ties among individuals, and provide recommendations. We propose the idea of Implicit Affinity Networks (IANs) to build, visualize, and track affinities among groups of individuals. IANs are simple, interactive graphical representations that users may navigate to uncover interesting patterns. This thesis describes a system supporting the construction of IANs and evaluates it in the context of family history and online communities.

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Strain-Based Electrical Properties Of Systems Of Carbon Nanotubes Embedded In Parylene, David D. Allred, Jon Brame, Johnathan Goodsell, Stephanie Getty Jan 2007

Strain-Based Electrical Properties Of Systems Of Carbon Nanotubes Embedded In Parylene, David D. Allred, Jon Brame, Johnathan Goodsell, Stephanie Getty

Faculty Publications

We have fabricated flexible electronic devices to test the strain-based change in resistance of a network of single-walled carbon nanotubes (SWCNTs) for use in microscale, high resolution magnetometry. To do this, we first develop a simple, reliable method to obtain catalyst nanoparticles for carbon nanotube growth through indirect, thin-film evaporation. Next we fabricate a two-terminal SWCNT device on a rigid substrate. We then transfer the device, intact, to a flexible substrate for strain testing. Herein, we report progress in growth and measurement techniques.

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Skuery: Manipulation Of S-Expressions Using Xquery Techniques, Kevin Burke Tew Jan 2007

Skuery: Manipulation Of S-Expressions Using Xquery Techniques, Kevin Burke Tew

Theses and Dissertations

Data query operations inside programming languages presently perform their functions through the use of domain-specific, declarative expressions and by way of course-grain, API library calls. These methods of operation are practiced by relational databases as well as semistructured XML data stores. Layers of translation, which are necessary to transform data and instructions from the domain of programming languages to data query systems, negtatively effect the performance of data query operations. Skuery resolves this impedance by adopting XML as a native data type with a native representation (SXML). Likewise, query operations are defined in a general purpose programming language (Scheme in …

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A Cognitive Robotics Approach To Comprehending Human Language And Behaviors, Deryle W. Lonsdale, D. Paul Benjamin, Damian Lyons Jan 2007

A Cognitive Robotics Approach To Comprehending Human Language And Behaviors, Deryle W. Lonsdale, D. Paul Benjamin, Damian Lyons

Faculty Publications

The ADAPT project is a collaboration of researchers in linguistics, robotics and artificial intelligence at three universities. We are building a complete robotic cognitive architecture for a mobile robot designed to interact with humans in a range of environments, and which uses natural language and models human behavior. This paper concentrates on the HRI aspects of ADAPT, and especially on how ADAPT models and interacts with humans.

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Analogical Modeling: An Update, Deryle W. Lonsdale, David Eddington Jan 2007

Analogical Modeling: An Update, Deryle W. Lonsdale, David Eddington

Faculty Publications

Analogical modeling is a supervised exemplar-based approach that has been widely applied to predict linguistic behavior. The paradigm has been well documented in the linguistics and cognition literature, but is less well known to the machine learning community. This paper sets out some of the basics of the approach, including a simplified example of the fundamental algorithm’s operation. It then surveys some of the recent analogical modeling language applications, and sketches how the computational system has been enhanced lately to offer users increased flexibility and processing power. Some comparisons and contrasts are drawn between analogical modeling and other language modeling …

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Clustering Streaming Music Via The Temporal Similarity Of Timbre, Jacob Merrell, Bryan S. Morse, Dan A. Ventura Jan 2007

Clustering Streaming Music Via The Temporal Similarity Of Timbre, Jacob Merrell, Bryan S. Morse, Dan A. Ventura

Faculty Publications

We consider the problem of measuring the similarity of streaming music content and present a method for modeling, on the fly, the temporal progression of a song’s timbre. Using a minimum distance classification scheme, we give an approach to classifying streaming music sources and present performance results for auto-associative song identification and for content-based clustering of streaming music. We discuss possible extensions to the approach and possible uses for such a system.

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Generating Ontologies Via Language Components And Ontology Reuse, Deryle W. Lonsdale, Yihong Ding, David W. Embley, Martin Hepp, Li Xu Jan 2007

Generating Ontologies Via Language Components And Ontology Reuse, Deryle W. Lonsdale, Yihong Ding, David W. Embley, Martin Hepp, Li Xu

Faculty Publications

Realizing the Semantic Web involves creating ontologies, a tedious and costly challenge. Reuse can reduce the cost of ontology engineering. Semantic Web ontologies can provide useful input for ontology reuse. However, the automated reuse of such ontologies remains underexplored. This paper presents a generic architecture for automated ontology reuse. With our implementation of this architecture, we show the practicality of automating ontology generation through ontology reuse. We experimented with a large generic ontology as a basis for automatically generating domain ontologies that fit the scope of sample natural-language web pages. The results were encouraging, resulting in five lessons pertinent to …

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