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Full-Text Articles in Physical Sciences and Mathematics

Improving And Extending Behavioral Animation Through Machine Learning, Jonathan J. Dinerstein Apr 2005

Improving And Extending Behavioral Animation Through Machine Learning, Jonathan J. Dinerstein

Theses and Dissertations

Behavioral animation has become popular for creating virtual characters that are autonomous agents and thus self-animating. This is useful for lessening the workload of human animators, populating virtual environments with interactive agents, etc. Unfortunately, current behavioral animation techniques suffer from three key problems: (1) deliberative behavioral models (i.e., cognitive models) are slow to execute; (2) interactive virtual characters cannot adapt online due to interaction with a human user; (3) programming of behavioral models is a difficult and time-intensive process. This dissertation presents a collection of papers that seek to overcome each of these problems. Specifically, these issues are alleviated …


Interactive Image Filling-In, Teryl Lynne Arnold Apr 2005

Interactive Image Filling-In, Teryl Lynne Arnold

Theses and Dissertations

Removing unwanted scratches or objects from an image in an undetectable manner is a technique that has been researched for its many useful and varied applications, such as removing scratches, defects, super-imposed text, or even entire objects from a scene. Currently there is a wide variety of algorithms that fill in unwanted regions, none of which incorporate user preferences into the structure completion process. By building a framework to incorporate user preferences into the filling-in process, user input can be utilized to more effectively fill in damaged regions in an image. User input can influence the filling-in process in a …


T-Spline Merging, Heather Ipson Apr 2005

T-Spline Merging, Heather Ipson

Theses and Dissertations

Geometric models, such as for use in CAD/CAM or animation, are often constructed in a piece-wise fashion. Historically, these models have been made of NURBS surfaces. For various reasons it is problematic and often times mathematically impossible to combine several NURBS models into one continuous surface. The recent invention of a surface type called T-splines has made the combining of NURBS surfaces into a single continuous surface possible, but much of the mathematics has yet to be explored. This thesis explores the mathematics and algorithms necessary to merge multiple NURBS, T-spline, or T-NURCC surfaces into a single continuous surface. This …


January: Search Based On Social Insect Behavior, Peter C. Lamborn Apr 2005

January: Search Based On Social Insect Behavior, Peter C. Lamborn

Theses and Dissertations

January is a group of interacting stateless model checkers. Each agent functions on a processor located on a super computer or a network of workstations (NOW). The agent's search pattern is a semi-random walk based on the behavior of the grey field slug (Agriolimax reticulatus), the house fly (Musca domestica), and the black ant (Lassius niger). The agents communicate to lessen the amount of duplicate work being done. Every algorithm has a memory threshold above which they search efficiently. This threshold varies not only by model but also by algorithm. Janaury's threshold is lower than the thresholds of other algorithms …


Improving Routing Security Using A Decentralized Public Key Distribution Algorithm, Jeremy C. Goold Apr 2005

Improving Routing Security Using A Decentralized Public Key Distribution Algorithm, Jeremy C. Goold

Theses and Dissertations

Today's society has developed a reliance on networking infrastructures. Health, financial, and many other institutions deploy mission critical and even life critical applications on local networks and the global Internet. The security of this infrastructure has been called into question over the last decade. In particular, the protocols directing traffic through the network have been found to be vulnerable. One such protocol is the Open Shortest Path First (OSPF) protocol. This thesis proposes a security extension to OSPF containing a decentralized certificate authentication scheme (DecentCA) that eliminates the single point of failure/attack present in current OSPF security extensions. An analysis …


The Effects Of Nutrient Concentrations On Macroinvertebrate Distributions In Georgia, Paula Michele Pollock Brossett Apr 2005

The Effects Of Nutrient Concentrations On Macroinvertebrate Distributions In Georgia, Paula Michele Pollock Brossett

Theses and Dissertations

Nutrients are considered the second largest nonpoint source pollutant in Georgia's running water ecosystems. Nutrients can naturally occur in low amounts and are typically increased in streams as a result of industry, agriculture, silviculture, and urbanization. In large amounts, nutrients can cause many problems to occur in the stream ecosystem. Macroinvertebrates have been established as good indicators for determining the level of impairment of a stream; however, not much research has been done on how nutrients affect macroinvertebrates in a stream. Approximately 225 reference and impaired streams were sampled over a 3 - year field season, (index period from September …


Keyword Spotting Using Normalization Of Posterior Probability Confidence Measures, Rachna Vijay Vargiya Apr 2005

Keyword Spotting Using Normalization Of Posterior Probability Confidence Measures, Rachna Vijay Vargiya

Theses and Dissertations

Keyword spotting techniques deal with recognition of predefined vocabulary keywords from a voice stream. This research uses HMM based keyword spotting algorithms for this purpose. The three most important components of a keyword detection system are confidence measure, pruning technique and evaluation of results. We suggest that best match for a keyword would be an alignment in which all constituent states have high emission probabilities. Therefore score of even the worst subsequence must also be better than a threshold and a path can be represented by the score of its worst subsequence match. This confidence measure is called Real Fitting. …


Geology Of The Tierras Blancas Area In The Southeastern Acambay Graben, Central Mexico, Lonnie T. Mercer Mar 2005

Geology Of The Tierras Blancas Area In The Southeastern Acambay Graben, Central Mexico, Lonnie T. Mercer

Theses and Dissertations

Pliocene-Pleistocene sediments in the southeastern Acambay graben, central Mexico have yielded mammal fossils, including Equus simplicidens, cf. Rhynchotherium, ?Camelops, Mammuthus sp., Bison sp., and Antilocapra sp. The fossiliferous sediments include a period of lacustrine sedimentation in the late Pliocene-early Pleistocene that interrupted fluvial and alluvial sedimentation during the early Pliocene and Pleistocene. The sediments deposited in this late Pliocene paleolake record a history of lake level fluctuations, shown by lithologic variations in lacustrine sediments and abundance of vertebrate burrows. Volcanic and tectonic events in the Acambay graben were the major controls on sedimentation during Pliocene-Pleistocene time. …


Alterations In Uterine And Placental Sodium Pump Abundance May Contribute To The Onset Of Mouse Labor, Carlos Jacob Vance Mar 2005

Alterations In Uterine And Placental Sodium Pump Abundance May Contribute To The Onset Of Mouse Labor, Carlos Jacob Vance

Theses and Dissertations

Objective: Reductions in sodium pump (SP) abundance can give rise to increases in contractile force in uterine and vascular smooth muscle as well as an increased secretion in secretory cells, including potentially those of the placenta. To determine whether the mouse might serve as a model for human pregnancy in terms of the SP and to determine whether changes in SP abundance anticipate or follow labor, we studied pregnant mice over the final trimester of their pregnancy.

Study Design: C57Bl6 dams (n=46) were bred and studied during their pregnancy. Animals (n=4) were sacrificed at specific gestational time points. Other mice …


Development Of A Defense Meteorological Satellite Program (Dmsp) F-15 Disturbance Storm-Time (Dst) Index, James M. Bono Mar 2005

Development Of A Defense Meteorological Satellite Program (Dmsp) F-15 Disturbance Storm-Time (Dst) Index, James M. Bono

Theses and Dissertations

As the DoD's use of space and space assets increases, so does its need for timely and accurate predictions of space weather conditions. A good understanding of the data from satellites together with data from ground stations can help model and determine variations in the space environment. An accurate, real-time Disturbance storm-time (Dst) index would be a primary input into current and future space weather models The Dst index is a measure of geomagnetic activity used to assess the severity of magnetic storms. The index is based on the average value of the horizontal component of the Earth's magnetic field …


Ion Transmission In The First Vacuum Stage Of An Inductively Coupled Plasma Mass Spectrometer, Jeffrey Harris Macedone Mar 2005

Ion Transmission In The First Vacuum Stage Of An Inductively Coupled Plasma Mass Spectrometer, Jeffrey Harris Macedone

Theses and Dissertations

The inductively coupled plasma mass spectrometer (ICP-MS) is the instrument of choice for trace and ultra-trace elemental analysis. However, the ICP-MS suffers from matrix effects. Matrix effects occur when instrument response varies as the composition of the sample matrix is changed. Matrix effects, or non-spectroscopic interferences, limit the accuracy of routine analysis. Identification of the sources of matrix effects provide a basis for reducing or eliminating them. As inaccuracies in the ICP-MS are more severe than those in the ICP atomic emission spectrometer, the problem may be due, at least in part, to the vacuum interface used to couple the …


Sequence Stratigraphy Of The Bridal Veil Falls Limestone, Carboniferous, Lower Oquirrh Group, On Cascade Mountain, Utah: A Standard Morrowan Cyclostratigraphy For The Oquirrh Basin, David Joseph Shoore Mar 2005

Sequence Stratigraphy Of The Bridal Veil Falls Limestone, Carboniferous, Lower Oquirrh Group, On Cascade Mountain, Utah: A Standard Morrowan Cyclostratigraphy For The Oquirrh Basin, David Joseph Shoore

Theses and Dissertations

The Bridal Veil Falls Limestone (lowest 400 meters of the Permo-Carboniferous Oquirrh Group) is well exposed on the flanks of Cascade Mountain (Wasatch Front and adjacent mountain ranges) near Provo, Utah. Because of its excellent exposure and location in the heart of the Oquirrh depocenter, this area was selected to develop a sequence stratigraphic framework for Morrowan rocks that may be applied throughout the Oquirrh basin (NW Utah and southern Idaho) as well as the adjacent Ely and Bird Springs troughs. Eleven partial to complete sections of the Bridal Veil Falls Limestone were measured along the west and north flanks …


A Sampling And Transformation Approach To Solving Random Differential Equations, Roger A. Erich Mar 2005

A Sampling And Transformation Approach To Solving Random Differential Equations, Roger A. Erich

Theses and Dissertations

This research explores an innovative sampling method used to conduct uncertainty analysis on a system with one random input. Given the distribution of the random input, X, we seek to find the distribution of the output random variable Y. When the functional form of the transformation Y=g(X) is not explicitly known, complicated procedures, such as stochastic projection or Monte Carlo simulation must be employed. The main focus of this research is determining the distribution of the random variable Y=g(X) where g(X) is the solution to an ordinary differential equation and X is a random parameter. Here, y=g(X) is approximated by …


Deconvolution Analysis Of Laser Pulse Profiles From 3-D Ladar Temporal Returns, Michael D. Walter Mar 2005

Deconvolution Analysis Of Laser Pulse Profiles From 3-D Ladar Temporal Returns, Michael D. Walter

Theses and Dissertations

Three-dimensional laser imaging systems offer important advantages for battlefield applications, such as night-time targeting and tactical reconnaissance. Recently developed technologies used by coherent detection systems that collect temporally resolved images include arrays of Avalanche Photo-Diodes (APD), Geiger mode APDs, and photo-diodes. Frequently, LADAR systems produce waveforms from each detector that characterize the convolution of the transmitted laser pulse with the target surface. The pulse convolution generates uncertainty as to the precise location of a target surface, which can severely impact various weapon systems' targeting capability. This work analyzes two deconvolution techniques: Wiener filtering and an iterative process derived from the …


The Effects Of Fault-Induced Stress Anisotropy On Fracturing, Folding And Sill Emplacement: Insights From The Bowie Coal Mines, Southern Piceance Basin, Western Colorado., Eric Dean Robeck Mar 2005

The Effects Of Fault-Induced Stress Anisotropy On Fracturing, Folding And Sill Emplacement: Insights From The Bowie Coal Mines, Southern Piceance Basin, Western Colorado., Eric Dean Robeck

Theses and Dissertations

The recognition of fault-perturbed stress fields is an important tool in areas of mineral or hydrocarbon exploration. The Bowie underground coal mines of western Colorado expose a reverse-reactivated growth fault that perturbed the stress field during cleat (fracture) formation, rotating cleat orientations up to 500 m on both sides of the fault. Two unusual fracture types are found only in coal adjacent to the fault: (1) concentric cleats, highly curved fractures that form blocks resembling balls or eggs and (2) horsetail cleats, striated surfaces that superficially resemble shattercones and result from shear failure in coal. Numerical models created with the …


Steady State Stress In A Coated Infinite Half-Space Subjected To A Moving Load, Jason M. Cruthirds Mar 2005

Steady State Stress In A Coated Infinite Half-Space Subjected To A Moving Load, Jason M. Cruthirds

Theses and Dissertations

This research investigates the use of coatings to mitigate the stress distribution into an infinite half-space. High energy impact phenomenon at velocities exceeding the speed of sound is an important area of interest to the Air Force Research Laboratory. Holloman Air Force Base's High Speed Test Track sustains significant damage due to this phenomenon. In this thesis, the track system and coating are modeled analytically with equations of motion in terms of linear displacements. Coating thickness and material properties of epoxy or polymer laminates are investigated to understand their affect of stress distribution in the rail. An analytic solution is …


A Conceptual Model Of Groundwater Flow At The Midway, Utah Fish Hatchery As Constrained By Geochemical, Physical Hydrogeological, And Geophysical Methods, Camille Durrant Mar 2005

A Conceptual Model Of Groundwater Flow At The Midway, Utah Fish Hatchery As Constrained By Geochemical, Physical Hydrogeological, And Geophysical Methods, Camille Durrant

Theses and Dissertations

In addition to a loss of potential revenues from Utah's $393 million sport fishing industry, the state expends millions of dollars every year on costs associated with whirling disease mitigation and prevention. A state fish hatchery at Midway, Utah was closed when the shallow unconfined aquifer being used for fish culture by spring discharge was deemed to be contaminated by whirling disease. An alternative water source may exist in a confined aquifer below this contaminated unconfined aquifer. However, the complex hydrostratigraphy presents a challenge in determining if this source is a viable resource for fish culture. Geological, physical, chemical, geophysical, …


A Uintan (Late Middle Eocene) Flora And Fauna From The Uinta Basin, Utah, Stephen Dee Sandau Mar 2005

A Uintan (Late Middle Eocene) Flora And Fauna From The Uinta Basin, Utah, Stephen Dee Sandau

Theses and Dissertations

Late Middle Eocene time marks one of the most dynamic periods of the Paleogene in the western interior of North America. Analysis of an extensive, new collection of plant, invertebrate, and vertebrae fossils from the Uinta Formation in the Uinta Basin, south of Myton, Utah, USA, provides evidence of environmental change. Paleobotanical specimens are preserved in late stage Uinta Lake sediments and coarse-grained fluvial sediments which are stratigraphically 650 to 660 m above the Green River Formation. Deposition rates estimates of 18 to 55 cm/kyr, for Uinta Lake sediments in the Uinta Basin suggest a period of 1.18 Ma to …


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

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

Theses and Dissertations

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


In-Line Particulate Transport And Dispersion Modeling Using The Regional Atmospheric Modeling System (Rams), John W. Englert Mar 2005

In-Line Particulate Transport And Dispersion Modeling Using The Regional Atmospheric Modeling System (Rams), John W. Englert

Theses and Dissertations

There are a number of analytical and semi-empirical models that describe the behavior of particulate matter in the atmosphere. Many of these require modification for all types of weather, dry versus wet deposition, and overall effects can be quite non-linear. Rainfall (rate, drop size, etc.), snowfall (rate, flake size, etc.), humidity, pressure, temperature, and combination of these greatly affect particle settling and washout rates. To that end, a method for tracking released constituents using the Regional Atmospheric Modeling System (RAMS) microphysics package is developed by modifying one of the hydrometeor categories (hail) in the microphysics package. The RAMS microphysics package …


Two-Photon Ionization Of The Calcium 4s3d 1d2 Level In An Optical Dipole Trap, Jared Estus Daily Mar 2005

Two-Photon Ionization Of The Calcium 4s3d 1d2 Level In An Optical Dipole Trap, Jared Estus Daily

Theses and Dissertations

This thesis reports an optical dipole trap for atomic calcium. The dipole trap is loaded from a magneto-optical trap (MOT) of calcium atoms cooled near the Doppler limit (~1 mK). The dipole trap is formed by a large-frame argon ion laser focused to 20 microns into the center of the MOT. This laser runs single-line at 488 nm with a maximum power of 10.6 watts. These parameters result in a trap of 125 mK for calcium atoms in the 4s3d 1D2 state. The 488 nm light also photo-ionizes the trapped atoms due to a near-resonant transition to the 4s4f 1F3 …


Using Liquid Crystal Spatial Light Modulators For Closed Loop Tracking And Beam Steering With Phase Holography, Michael J. Perry Mar 2005

Using Liquid Crystal Spatial Light Modulators For Closed Loop Tracking And Beam Steering With Phase Holography, Michael J. Perry

Theses and Dissertations

Optical Phased Array (OPA) technology offers advantages in the reduction of size, weight, and power of optical steering devices. Nematic liquid crystal (LC) spatial light modulators (SLMs) have been studied as a potential candidate for building non-mechanical OPAs. They can steer a laser beam and split the beam into multiple beams. This thesis builds upon the prior research showing each split beam can be individually controlled, including variation in intensity. A closed loop tracking scenario shows the flexibility of the SLM by tracking and stabilizing an incoming beam. Results show that applying a phase grating to the SLM has limitations …


Characterizing A Neutron Energy Spectrum Using A "Forward Edge" Neutron Time-Of-Flight Spectroscopy Technique, Jeffrey S. Spear Mar 2005

Characterizing A Neutron Energy Spectrum Using A "Forward Edge" Neutron Time-Of-Flight Spectroscopy Technique, Jeffrey S. Spear

Theses and Dissertations

A Fermi-style thermal neutron disc chopper was designed, constructed, and calibrated in conjunction with a boron-loaded organic scintillator for use in creating a forward edge neutron time-of-flight spectroscopy technique. The forward edge neutron time-of-flight spectroscopy technique inferred the characteristics of a neutron energy spectrum. The system analyzed the spectrum of a moderated and unmoderated PuBe source with the aid of a MATLAB code. Through the use of pulse shape analysis techniques and energy spectroscopy the thermal neutron capture event was identified and isolated. Data analysis provided positive feedback in the disc chopper's ability to partially attenuate higher energy neutrons in …


Electrical Activation Studies Of Silicon Implanted AlXGa1-XN, Timothy W. Zens Mar 2005

Electrical Activation Studies Of Silicon Implanted AlXGa1-XN, Timothy W. Zens

Theses and Dissertations

Electrical activation studies of silicon implanted AlxGa1-xN grown on sapphire substrates were conducted as a function of ion dose, anneal temperature, and anneal time. Silicon ion doses of 1x1013, 5x1013, and 1x1014 cm-2 were implanted in AlxGa1-xN samples with aluminum mole fractions of 0.1 and 0.2 at an energy of 200 keV at room temperature. The samples were proximity cap annealed at temperatures from 1100 to 1350 ºC and anneal times of 20 to 40 minutes with a 500 Å thick AlN cap in a nitrogen environment. The Hall coefficient …


Thor: The Hybrid Online Repository, Timothy W. Van Der Horst Mar 2005

Thor: The Hybrid Online Repository, Timothy W. Van Der Horst

Theses and Dissertations

Digital credentials enable users to perform secure interactions by proving either their identity or that they posses certain attributes. Special care is taken to protect these credentials and their associated private keys during transaction time. However, protection of these items outside of the transaction is often delegated to a secure credential repository. A mobile environment creates significant challenges for secure repositories. We examine these challenges with respect to existing repository practices and produce a set of requirements that a repository must meet in order to cope with the harshness of a mobile environment. We also present the design and implementation …


Web Usability Guidelines For Air Force Knowledge Now Web Site, Gary A. Felax Mar 2005

Web Usability Guidelines For Air Force Knowledge Now Web Site, Gary A. Felax

Theses and Dissertations

The Department of Defense Net-Centric Data Strategies number one key attribute is to ensure data is visible, available, and usable when and where needed to accelerate decision-making. The Internet provides opportunities for quick and efficient disseminating of information to the public, distributing information throughout the Air Force, and accessing information from a variety of sources. In 2002, the Air Force CIO designated the Air Force Knowledge Now (AFKN) as the center of excellence for Knowledge Management. The site is a one-stop resource, providing access to a great depth and breadth of information. This study seeks to determine how usable and …


Non-Adiabatic Energy Surfaces Of The B+H2 Systems, Lachlan T. Belcher Mar 2005

Non-Adiabatic Energy Surfaces Of The B+H2 Systems, Lachlan T. Belcher

Theses and Dissertations

In order to solve the dynamics of a system, the kinetic energy operator of the Hamiltonian must be diagonalized. Diagonalization requires rotation of the system into a non-adiabatic representation. This rotation is a coupling angle determined by the derivative coupling terms. Derivative coupling terms are calculated using Columbus and Brooklyn, software packages. Separation of internal dynamics characterized by Jacobi coordinates, and external dynamics characterized by a set of Euler angles and the center of mass position, requires a transformation from Cartesian coordinates to Jacobi coordinates required for subsequent dynamical calculations. Previous attempts to solve for non-adiabatic energy surfaces in this …


Assessing Information Trustability In A Secure Web Services Environment, Charles G. Penner Mar 2005

Assessing Information Trustability In A Secure Web Services Environment, Charles G. Penner

Theses and Dissertations

Decisions are made based on available information. A decision support system endeavors to provide information that is timely, accurate, and trustable. Information gathered from secure web service transactions has attributes that can be used to assess a level of trustability. The trust assessments enable a decision maker to determine a basis for confidence in the information presented from the web service. Existing trust assessment models do not provide a way to determine from a particular trust assessment what information attributes contributed to its computation. The present work creates trust values that retain and denote meaning, allowing a decision maker to …


Lethality Of Bacillus Anthracis Spores Due To Short Duration Heating Measured Using Infrared Spectroscopy, Kristina M. Goetz Mar 2005

Lethality Of Bacillus Anthracis Spores Due To Short Duration Heating Measured Using Infrared Spectroscopy, Kristina M. Goetz

Theses and Dissertations

There are a number of analytical and semi-empirical models that describe the behavior of particulate matter in the atmosphere. Many of these require modification for all types of weather, dry versus wet deposition, and overall effects can be quite non-linear. Rainfall (rate, drop size, etc.), snowfall (rate, flake size, etc.), humidity, pressure, temperature, and combination of these greatly affect particle settling and washout rates. To that end, a method for tracking released constituents using the Regional Atmospheric Modeling System (RAMS) microphysics package is developed by modifying one of the hydrometeor categories (hail) in the microphysics package. The RAMS microphysics package …


Environmental Acoustic Transfer Functions And Filtering Acoustic Signals, Brandon P. Dias Mar 2005

Environmental Acoustic Transfer Functions And Filtering Acoustic Signals, Brandon P. Dias

Theses and Dissertations

Signal processing is the method of taking a given signal and extracting useful information, usually by a means of a transformation of some kind. Acoustic signals are functions of time in which the output is a pressure or a velocity potential response. An acoustic signal is affected by the environment in which it propagates, so one can attempt to remove the environmental effects to extract the useful information, in this case the original signal. This thesis will derive, in a mathematical framework, the process of filtering extraneous signals in a way that yields the original signal, and will then apply …