Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Theses and Dissertations

Discipline
Institution
Keyword
Publication Year
File Type

Articles 6181 - 6210 of 8341

Full-Text Articles in Physical Sciences and Mathematics

A Direct Algorithm For The K-Nearest-Neighbor Classifier Via Local Warping Of The Distance Metric, Tohkoon Neo Nov 2007

A Direct Algorithm For The K-Nearest-Neighbor Classifier Via Local Warping Of The Distance Metric, Tohkoon Neo

Theses and Dissertations

The k-nearest neighbor (k-NN) pattern classifier is a simple yet effective learner. However, it has a few drawbacks, one of which is the large model size. There are a number of algorithms that are able to condense the model size of the k-NN classifier at the expense of accuracy. Boosting is therefore desirable for increasing the accuracy of these condensed models. Unfortunately, there does not exist a boosting algorithm that works well with k-NN directly. We present a direct boosting algorithm for the k-NN classifier that creates an ensemble of models with locally modified distance weighting. An empirical study conducted …

Go to article

Analysis And Implementation Of High-Order Compact Finite Difference Schemes, Jonathan G. Tyler Nov 2007

Analysis And Implementation Of High-Order Compact Finite Difference Schemes, Jonathan G. Tyler

Theses and Dissertations

The derivation of centered compact schemes at interior and boundary grid points is performed and an analysis of stability and computational efficiency is given. Compact schemes are high order implicit methods for numerical solutions of initial and/or boundary value problems modeled by differential equations. These schemes generally require smaller stencils than the traditional explicit finite difference counterparts. To avoid numerical instabilities at and near boundaries and in regions of mesh non-uniformity, a numerical filtering technique is employed. Experiments for non-stationary linear problems (convection, heat conduction) and also for nonlinear problems (Burgers' and KdV equations) were performed. The compact solvers were …

Go to article

Clustering Methods For Delineating Regions Of Spatial Stationarity, Jared M. Collings Nov 2007

Clustering Methods For Delineating Regions Of Spatial Stationarity, Jared M. Collings

Theses and Dissertations

This paper seeks to further investigate data extracted by the use of Functional Magnetic Resonance Imaging (FMRI) as it is applied to brain tissue and how it measures blood flow to certain areas of the brain following the application of a stimulus. As a precursor to detailed spatial analysis of this kind of data, this paper develops methods of grouping data based on the necessary conditions for spatial statistical analysis. The purpose of this paper is to examine and develop methods that can be used to delineate regions of stationarity. One of the major assumptions used in spatial estimation is …

Go to article

Construction Of A Calcium Matter-Wave Interferometer, Christopher Joseph Erickson Nov 2007

Construction Of A Calcium Matter-Wave Interferometer, Christopher Joseph Erickson

Theses and Dissertations

I describe the construction of a calcium matter-wave interferometer. The interferometer is based on a Ramsey-Borde scheme, and uses a thermal beam of atoms excited by an optical-frequency transition in calcium. In our experiment four pi/2 pulses of light are delivered to the atoms, which split and recombine the wave functions of the atoms. Our experimental design minimizes first-order Doppler shifts, and allows for the cancellation of systematic errors including phase shifts due to rotation and acceleration. I describe the individual components of the interferometer and its assembly. The requirements for the electronics used in the experiment as well as …

Go to article

Microchip Liquid Chromatography And Capillary Electrophoresis Separations In Multilayer Microdevices, Hernan Vicente Fuentes Nov 2007

Microchip Liquid Chromatography And Capillary Electrophoresis Separations In Multilayer Microdevices, Hernan Vicente Fuentes

Theses and Dissertations

In this dissertation, several microfabricated devices are introduced to develop new applications in the area of chemical analysis. Electrochemical micropumps, chip-based liquid chromatography systems and multilayer capillary electrophoresis microdevices with crossover channels were fabricated using various substrates such as poly(dimethylsiloxane) (PDMS), glass, and poly(methyl methacrylate) (PMMA). I have demonstrated pressure-driven pumping of liquids in microfabricated channels using electrochemical actuation. PDMS-based micropumps were integrated easily with channel-containing PMMA substrates. Flow rates on the order of ~10 µL/min were achieved using low voltages (10 V). The potential of electrolysis-based pumping in microchannels was further evaluated for pressure driven microchip liquid chromatography (LC). …

Go to article

Microfluidic Electro-Osmotic Flow Pumps, John Mason Edwards Nov 2007

Microfluidic Electro-Osmotic Flow Pumps, John Mason Edwards

Theses and Dissertations

The need for miniaturized, portable devices to separate and detect unknown compounds has greatly multiplied, leading to an increased interest in microfluidics. Total integration of the detector and pump are necessary to decrease the overall size of the microfluidic device. Using previously developed thin film technologies, an electroosmotic flow (EOF) pump was incorporated in a microfluidic liquid chromatography device. An EOF pump was chosen because of its simple design and small size. EOF pumps fabricated on silicon and glass substrates were evaluated. The experimental flow rates were 0.19-2.30 microliters/minute for 40-400 V. The theoretical pump efficiency was calculated along with …

Go to article

An Approach To Mapping Of Shallow Petroleum Reservoirs Using Integrated Conventional 3d And Shallow P- And Sh-Wave Seismic Reflection Methods At Teapot Dome Field In Casper, Wyoming, Anita Onohuome Okojie-Ayoro Nov 2007

An Approach To Mapping Of Shallow Petroleum Reservoirs Using Integrated Conventional 3d And Shallow P- And Sh-Wave Seismic Reflection Methods At Teapot Dome Field In Casper, Wyoming, Anita Onohuome Okojie-Ayoro

Theses and Dissertations

Using the famous Teapot Dome oil field in Casper, Wyoming, USA as a test case, we demonstrate how high-resolution compressional (P) and horizontally polarized shear (SH) wave seismic reflection surveys can overcome the limitations of conventional 3D seismic data in resolving small-scale structures in the very shallow subsurface (< 100-200 m (~328-656 ft)). We accomplish this by using small CMP intervals (5 ft and 2.5 ft, respectively) and a higher frequency source. The integration of the two high-resolution seismic methods enhances the detection and mapping of fine-scale deformation and stratigraphic features at shallow depth that cannot be imaged by conventional seismic methods. Further, when these two high-resolution seismic methods are integrated with 3D data, correlated drill hole logs, and outcrop mapping and trenching, a clearer picture of both very shallow reservoirs and the relationship between deep and shallow faults can be observed. For example, we show that the Shannon reservoir, which is the shallowest petroleum reservoir at Teapot Dome (depth to the top of this interval ranging from 76-198 m (250-650 ft)) can only be imaged properly with high-resolution seismic methods. Further, northeast-striking faults are identified in shallow sections within Teapot Dome. The strike of these faults is approximately orthogonal to the hinge of Teapot Dome. These faults are interpreted as fold accommodation faults. Vertical displacements across these faults range from 10 to 40 m (~33 to 131 ft), which could potentially partition the Shannon reservoir. The integration of 3D and high-resolution P-wave seismic interpretation helped us determine that some of the northeast-striking faults relate to deeper faults. This indicates that some deeper faults that are orthogonal to the fold hinge cut through the shallow Shannon reservoir. Such an observation would be important for understanding the effect on fluid communication between the deep and shallow reservoirs via these faults. Furthermore, the high-resolution seismic data provide a means to better constrain the location of faults mapped from drill hole logs. Relocation of theses faults may require re-evaluation of well locations as some attic oil may have not been drained in some Shannon blocks by present well locations. Therefore our study demonstrates how conventional 3D seismic data require additional seismic acquisition at smaller scales in order to image deformation in shallow reservoirs. Such imaging becomes critical in cases of shallow reservoirs where it is important to define potential problems associated with compartmentalization of primary production, hazard mitigation, enhanced oil recovery, or carbon sequestration.

Go to article

Supporting Flight Control For Uav-Assisted Wilderness Search And Rescue Through Human Centered Interface Design, Joseph L. Cooper Nov 2007

Supporting Flight Control For Uav-Assisted Wilderness Search And Rescue Through Human Centered Interface Design, Joseph L. Cooper

Theses and Dissertations

Inexpensive, rapidly deployable, camera-equipped Unmanned Aerial Vehicle (UAV) systems can potentially assist with a huge number of tasks. However, in many cases such as wilderness search and rescue (WiSAR), the potential users of the system may not be trained as pilots. Simple interface concepts can be used to build an interaction layer that allows an individual with minimal operator training to use the system to facilitate a search or inspection task. We describe an analysis of WiSAR as currently accomplished and show how a UAV system might fit into the existing structure. We then discuss preliminary system design efforts for …

Go to article

Counter-Flow Ion Mobility Analysis: Design, Instrumentation, And Characterization, Nosa Agbonkonkon Nov 2007

Counter-Flow Ion Mobility Analysis: Design, Instrumentation, And Characterization, Nosa Agbonkonkon

Theses and Dissertations

The quest to achieve high resolution in ion mobility spectrometry (IMS) has continued to challenge scientist and engineers in the field of separation science. The low resolution presently attainable in IMS has continued to negatively impact its utility and acceptance. Until now, efforts to improve the resolution have mainly focused on better instrumentation and detection methods. However, since the resolution of IMS is diffusion limited, it makes sense to address this limitation in order to attain high resolution. This dissertation presents a new IMS technique, which utilizes a high electric field and opposing high gas flow velocity with the aim …

Go to article

Intersection Algorithms Based On Geometric Intervals, Nicholas Stewart North Oct 2007

Intersection Algorithms Based On Geometric Intervals, Nicholas Stewart North

Theses and Dissertations

This thesis introduces new algorithms for solving curve/curve and ray/surface intersections. These algorithms introduce the concept of a geometric interval to extend the technique of Bézier clipping. A geometric interval is used to tightly bound a curve or surface or to contain a point on a curve or surface. Our algorithms retain the desirable characteristics of the Bézier clipping technique such as ease of implementation and the guarantee that all intersections over a given interval will be found. However, these new algorithms generally exhibit cubic convergence, improving on the observed quadratic convergence rate of Bézier clipping. This is achieved without …

Go to article

Accounting For Additional Heterogeneity: A Theoretic Extension Of An Extant Economic Model, Bradley John Barney Oct 2007

Accounting For Additional Heterogeneity: A Theoretic Extension Of An Extant Economic Model, Bradley John Barney

Theses and Dissertations

The assumption in economics of a representative agent is often made. However, it is a very rigid assumption. Hall and Jones (2004b) presented an economic model that essentially provided for a representative agent for each age group in determining the group's health level function. Our work seeks to extend their theoretical version of the model by allowing for two representative agents for each age—one for each of “Healthy” and “Sick” risk-factor groups—to allow for additional heterogeneity in the populace. The approach to include even more risk-factor groups is also briefly discussed. While our “extended” theoretical model is not applied directly …

Go to article

Applying Bayesian Ordinal Regression To Icap Maladaptive Behavior Subscales, Edward P. Johnson Oct 2007

Applying Bayesian Ordinal Regression To Icap Maladaptive Behavior Subscales, Edward P. Johnson

Theses and Dissertations

This paper develops a Bayesian ordinal regression model for the maladaptive subscales of the Inventory for Client and Agency Planning (ICAP). Because the maladaptive behavior section of the ICAP contains ordinal data, current analysis strategies combine all the subscales into three indices, making the data more interval in nature. Regular MANOVA tools are subsequently used to create a regression model for these indices. This paper uses ordinal regression to analyze each original scale separately. The sample consists of applicants for aid from Utah's Division of Services for Persons with Disabilities. Each applicant fills out the Scales of Independent Behavior"”Revised (SIB-R) …

Go to article

Heuristic Weighted Voting, Kristine Perry Monteith Oct 2007

Heuristic Weighted Voting, Kristine Perry Monteith

Theses and Dissertations

Selecting an effective method for combining the votes of classifiers in an ensemble can have a significant impact on the overall classification accuracy an ensemble is able to achieve. With some methods, the ensemble cannot even achieve as high a classification accuracy as the most accurate individual classifying component. To address this issue, we present the strategy of Heuristic Weighted Voting, a technique that uses heuristics to determine the confidence that a classifier has in its predictions on an instance by instance basis. Using these heuristics to weight the votes in an ensemble results in an overall average increase in …

Go to article

Error Sensor Placement For Active Control Of An Axial Cooling Fan, Benjamin M. Shafer Oct 2007

Error Sensor Placement For Active Control Of An Axial Cooling Fan, Benjamin M. Shafer

Theses and Dissertations

Recent experimental achievements in active noise control (ANC) for cooling fans have used near-field error sensors whose locations are determined according to a theoretical condition of minimized sound power. A theoretical point source model, based on the condition previously stated, reveals the location of near-field pressure nulls that may be used to optimize error sensor placement. The actual locations of these near-field pressure nulls for both an axial cooling fan and a monopole loudspeaker were measured over a two-dimensional grid with a linear array of microphones. The achieved global attenuation for each case is measured over a hemisphere located in …

Go to article

Collision Broadening Using Alkali-Filled, Hollow Core Fibers, Luke P. Rodgers Oct 2007

Collision Broadening Using Alkali-Filled, Hollow Core Fibers, Luke P. Rodgers

Theses and Dissertations

The goal of this research was to demonstrate the possibility of collision broadening in a cesium-filled, hollow-core fiber as an alternative to the proven technique of pressure broadening. Theoretically, alkali electrons should relax from the 2P3/2 to the 2P1/2 level and the absorption spectrum should collisionally broaden due to the presence of fiber walls, as opposed to the more common pressure broadening method. An absorption dip located at 852.34nm was recorded in a pressure broadened comparison leg. This data was used as a baseline during analysis of the fiber leg's data. While the fiber was successfully …

Go to article

Time Resolution Of Collapse Events During The Progation Of Ultraviolet Filaaments, Teresa J. Fondren Oct 2007

Time Resolution Of Collapse Events During The Progation Of Ultraviolet Filaaments, Teresa J. Fondren

Theses and Dissertations

Long distance propagation, or filamentation, of short, intense laser pulses is suggested to be possible through the balance of two effects: self-focusing, when a nonlinear index of refraction of air is induced by high intensities, and de-focusing, due to the plasma created by the pulse. Applications for filamentation include areas such as remote sensing and directed energy. A split-step spectral propagation simulation is used to model the behavior of a high intensity ultraviolet laser pulse propagating through air. Convergence of femtosecond duration collapses that form on the leading edge of the pulse in the time domain is achieved with an …

Go to article

Limitations And Extensions Of The Wolf-Phc Algorithm, Philip R. Cook Sep 2007

Limitations And Extensions Of The Wolf-Phc Algorithm, Philip R. Cook

Theses and Dissertations

Policy Hill Climbing (PHC) is a reinforcement learning algorithm that extends Q-learning to learn probabilistic policies for multi-agent games. WoLF-PHC extends PHC with the "win or learn fast" principle. A proof that PHC will diverge in self-play when playing Shapley's game is given, and WoLF-PHC is shown empirically to diverge as well. Various WoLF-PHC based modifications were created, evaluated, and compared in an attempt to obtain convergence to the single shot Nash equilibrium when playing Shapley's game in self-play without using more information than WoLF-PHC uses. Partial Commitment WoLF-PHC (PCWoLF-PHC), which performs best on Shapley's game, is tested on other …

Go to article

A General Quantum Mechanical Method To Predict Positron Spectroscopy, Paul E. Adamson Sep 2007

A General Quantum Mechanical Method To Predict Positron Spectroscopy, Paul E. Adamson

Theses and Dissertations

The nuclear-electronic orbital (NEO) method was modified and extended to positron systems. NEO - second-order Moeller-Plesset perturbation (MP2) energies and annihilation rates were calculated for the positronium hydride (PsH) system, and the effects of basis set size on correlation energies captured with the NEO-MP2 and NEO-full configuration interaction (FCI) methods are compared and discussed. Equilibrium geometries and vibrational energy levels were computed for the LiX and e+LiX (X = H, F, Cl) systems at the MP2 and NEO-MP2 levels. It was found that anharmonicity plays a significant role, specifically in the differences between the vibrational energy levels of …

Go to article

Phenomenological Model For Infrared Emissions From High-Explosive Detonation Fireballs, Kevin C. Gross Sep 2007

Phenomenological Model For Infrared Emissions From High-Explosive Detonation Fireballs, Kevin C. Gross

Theses and Dissertations

Time-resolved infrared spectra were recently collected via a Fourier-transform spectrometer (FTS) from the detonation fireballs of two types of conventional military munitions (CMM) as well as uncased TNT and four types of enhanced novel explosives (ENEs). The CMM spectra are dominated by continuum emission, and a single-temperature Planckian distribution, modified for atmospheric attenuation, captures most of the variation in the data. Some evidence of selective emission is identified by systematic patterns in the fit residuals. The behavior of these systematic residuals affords a distinction between the two types of CMMs studied. The uncased TNT and ENE spectra appear strongly influenced …

Go to article

Development Of A Method For Calculating Delta Scuti Rotational Velocities And Hydrogen Beta Color Indices, Tabitha Christi Buehler Sep 2007

Development Of A Method For Calculating Delta Scuti Rotational Velocities And Hydrogen Beta Color Indices, Tabitha Christi Buehler

Theses and Dissertations

To add to the understanding of the structure and evolution of Delta Scuti stars, 167 Delta Scutis north of -01 degrees declination and brighter than 13th magnitude have been observed spectroscopically. A method for calculating rotational velocity values and Hydrogen-Beta color indices for the stars in the data set with no previously published values is developed, using the stars in the data set brighter than 7th magnitude. Rotational velocity values for four stars with previously unknown values and Hydrogen-Beta index values for five stars with previously unknown values are calculated.

Go to article

Improving Neural Network Classification Training, Michael Edwin Rimer Sep 2007

Improving Neural Network Classification Training, Michael Edwin Rimer

Theses and Dissertations

The following work presents a new set of general methods for improving neural network accuracy on classification tasks, grouped under the label of classification-based methods. The central theme of these approaches is to provide problem representations and error functions that more directly improve classification accuracy than conventional learning and error functions. The CB1 algorithm attempts to maximize classification accuracy by selectively backpropagating error only on misclassified training patterns. CB2 incorporates a sliding error threshold to the CB1 algorithm, interpolating between the behavior of CB1 and standard error backpropagation as training progresses in order to avoid prematurely saturated network weights. CB3 …

Go to article

Collaborative, Trust-Based Security Mechanisms For A National Utility Intranet, Gregory M. Coates Sep 2007

Collaborative, Trust-Based Security Mechanisms For A National Utility Intranet, Gregory M. Coates

Theses and Dissertations

This thesis investigates security mechanisms for utility control and protection networks using IP-based protocol interaction. It proposes flexible, cost-effective solutions in strategic locations to protect transitioning legacy and full IP-standards architectures. It also demonstrates how operational signatures can be defined to enact organizationally-unique standard operating procedures for zero failure in environments with varying levels of uncertainty and trust. The research evaluates layering encryption, authentication, traffic filtering, content checks, and event correlation mechanisms over time-critical primary and backup control/protection signaling to prevent disruption by internal and external malicious activity or errors. Finally, it shows how a regional/national implementation can protect private …

Go to article

Parallelization Of Ant Colony Optimization Via Area Of Expertise Learning, Adrian A. De Freitas Sep 2007

Parallelization Of Ant Colony Optimization Via Area Of Expertise Learning, Adrian A. De Freitas

Theses and Dissertations

Ant colony optimization algorithms have long been touted as providing an effective and efficient means of generating high quality solutions to NP-hard optimization problems. Unfortunately, while the structure of the algorithm is easy to parallelize, the nature and amount of communication required for parallel execution has meant that parallel implementations developed suffer from decreased solution quality, slower runtime performance, or both. This thesis explores a new strategy for ant colony parallelization that involves Area of Expertise (AOE) learning. The AOE concept is based on the idea that individual agents tend to gain knowledge of different areas of the search space …

Go to article

A Framework For Analyzing And Mitigating The Vulnerabilities Of Complex Systems Via Attack And Protection Trees, Kenneth S. Edge Sep 2007

A Framework For Analyzing And Mitigating The Vulnerabilities Of Complex Systems Via Attack And Protection Trees, Kenneth S. Edge

Theses and Dissertations

Attack trees have been developed to describe processes by which malicious users attempt to exploit or break complex systems. Attack trees offer a method of decomposing, visualizing, and determining the cost or likelihood of attacks. Attack trees by themselves do not provide enough decision support to system defenders. This research develops the concept of using protection trees to offer a detailed risk analysis of a system. In addition to developing protection trees, this research improves the existing concept of attack trees and develops rule sets for the manipulation of metrics used in the security of complex systems. This research specifically …

Go to article

Scaling Ant Colony Optimization With Hierarchical Reinforcement Learning Partitioning, Erik J. Dries Sep 2007

Scaling Ant Colony Optimization With Hierarchical Reinforcement Learning Partitioning, Erik J. Dries

Theses and Dissertations

This research merges the hierarchical reinforcement learning (HRL) domain and the ant colony optimization (ACO) domain. The merger produces a HRL ACO algorithm capable of generating solutions for both domains. This research also provides two specific implementations of the new algorithm: the first a modification to Dietterich's MAXQ-Q HRL algorithm, the second a hierarchical ACO algorithm. These implementations generate faster results, with little to no significant change in the quality of solutions for the tested problem domains. The application of ACO to the MAXQ-Q algorithm replaces the reinforcement learning, Q-learning and SARSA, with the modified ant colony optimization method, Ant-Q. …

Go to article

Raman Fiber Lasers And Amplifiers Based On Multimode Fibers And Their Applications To Beam Cleanup, Nathan B. Terry Sep 2007

Raman Fiber Lasers And Amplifiers Based On Multimode Fibers And Their Applications To Beam Cleanup, Nathan B. Terry

Theses and Dissertations

Raman fiber lasers (RFLs) and Raman fiber amplifiers (RFAs) in multimode fibers were explored. The RFL based on a graded-index fiber was shown to be very efficient relative to RFLs based on singlemode fibers. Several configurations of the RFL were examined; the beam quality of the Stokes beam depended on the reflectivity of the output coupler and the Stokes power. When used as a beam combiner, the RFL was a highly efficient brightness converter. RFL configurations which used dichroic mirrors were shown to be potentially useful for RFLs based on very large fibers. The forward- and backward-seeded geometries of an …

Go to article

Multi-Objective Optimization For Speed And Stability Of A Sony Aibo Gait, Christopher A. Patterson Sep 2007

Multi-Objective Optimization For Speed And Stability Of A Sony Aibo Gait, Christopher A. Patterson

Theses and Dissertations

Locomotion is a fundamental facet of mobile robotics that many higher level aspects rely on. However, this is not a simple problem for legged robots with many degrees of freedom. For this reason, machine learning techniques have been applied to the domain. Although impressive results have been achieved, there remains a fundamental problem with using most machine learning methods. The learning algorithms usually require a large dataset which is prohibitively hard to collect on an actual robot. Further, learning in simulation has had limited success transitioning to the real world. Also, many learning algorithms optimize for a single fitness function, …

Go to article

Optimization Of Control Source And Error Sensor Locations In Free Field Active Noise Control, Connor Raymond Duke Aug 2007

Optimization Of Control Source And Error Sensor Locations In Free Field Active Noise Control, Connor Raymond Duke

Theses and Dissertations

Previous work has shown that active noise control (ANC) can be applied to axial cooling fans. Optimization of the control source and error sensor placement is desired to maximize the attenuation using ANC. A genetic algorithm was developed to find the optimal placement of control sources for a given primary source. The optimal configuration of control sources around a single primary source was shown to be a linear arrangement of the sources. This holds true for both two-dimensional as well as three-dimensional configurations. The higher-order radiation of the linear arrangement has also been verified experimentally, but the improvement in the …

Go to article

Development Of A New Ca Ii H And K Spectrophotometric Temperature Index, Kathleen Elizabeth Moncrieff Aug 2007

Development Of A New Ca Ii H And K Spectrophotometric Temperature Index, Kathleen Elizabeth Moncrieff

Theses and Dissertations

We are developing a new spectrophotometric temperature index based on the Ca II H and K lines. Because these lines are present even in very cool stars and because the Ca II H line is blended with the H-epsilon line in hot stars, this index should cover a very broad range of spectral types. Our data set consisted of 95 stars with spectral types ranging from O9 to M1. We examined five different indices based on the Ca II H + H-epsilon and K lines, as well as single-wavelength indices centered on each of the H-delta and H-gamma lines, which …

Go to article

Ontology Aware Software Service Agents: Meeting Ordinary User Needs On The Semantic Web, Muhammed Jassem Al Muhammed Aug 2007

Ontology Aware Software Service Agents: Meeting Ordinary User Needs On The Semantic Web, Muhammed Jassem Al Muhammed

Theses and Dissertations

To achieve the dream of the semantic web, it must be possible for ordinary users to invoke services. It is clear that users need simple-to-invoke-and-use services. This dissertation offers an ontological approach to declaratively create services that users can invoke using free-form, natural-language-like specifications. Our approach uses task ontologies as foundational knowledge. A task ontology consists of a domain ontology and a process ontology. The domain ontology encodes domain information such as possible constraints and instances in terms of object sets, relationship sets among these object sets, and operations over values in object sets and relationship sets. The process ontology …

Go to article

First Prev Next Last