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Three Pension Cost Methods Under Varying Assumptions, Linda S. Grizzle Jun 2005

Three Pension Cost Methods Under Varying Assumptions, Linda S. Grizzle

Theses and Dissertations

A pension plan administrator promises certain benefits in the future in exchange for labor today. In order to budget for this expense and create more security for the participant, the administrator uses a pension cost method. Each cost method assigns a portion of the future liability to the current year. This is called the normal cost. We calculate the normal cost under three cost methods using different annuity, interest and inflation assumptions. Then we make comparisons between cost methods as well as between assumption changes. The cost methods considered in this paper are the unit credit cost method, projected unit …

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Autologous Fibrinogen Purification And Concentration For Use In Fibrin Sealant, Steven M. Alston Jun 2005

Autologous Fibrinogen Purification And Concentration For Use In Fibrin Sealant, Steven M. Alston

Theses and Dissertations

Fibrinogen concentrates are used widely as a sealant during and after surgery to reduce blood loss. Commercially available fibrin sealants are made from pooled human blood, which carries the risk of blood-borne diseases, and are expensive. These concerns have brought to focus the need for autologous fibrinogen concentrates. This need has been addressed by utilizing a unique approach in which fibrinogen is precipitated from plasma with protamine. The physical properties of fibrin sealant prepared from fibrinogen precipitated with protamine were evaluated. The optimal precipitation conditions included a plasma protamine concentration of 10 mg/mL at room temperature. Under these conditions 96% …

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Explicit Computations Supporting A Generalization Of Serre's Conjecture, Brian Francis Hansen Jun 2005

Explicit Computations Supporting A Generalization Of Serre's Conjecture, Brian Francis Hansen

Theses and Dissertations

Serre's conjecture on the modularity of Galois representations makes a connection between two-dimensional Galois representations and modular forms. A conjecture by Ash, Doud, and Pollack generalizes Serre's to higher-dimensional Galois representations. In this paper we discuss an explicit computational example supporting the generalized claim. An ambiguity in a calculation within the example is resolved using a method of complex approximation.

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Commutation Relations For Functions Of Operators, Mark K. Transtrum, Jean-Francois S. Van Huele Jun 2005

Commutation Relations For Functions Of Operators, Mark K. Transtrum, Jean-Francois S. Van Huele

Faculty Publications

We derive an expression for the commutator of functions of operators with constant commutations relations in terms of the partial derivatives of these functions. This result extends the well-known commutation relation between one operator and a function of another operator. We discuss the range of applicability of the formula with examples in quantum mechanics

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Full Issue, Marriage &. Families Jun 2005

Full Issue, Marriage &. Families

Marriage and Families

No abstract provided.

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Parenting That Strengthens Each Family Member, Chris L. Porter, Nancy B. Rollins Jun 2005

Parenting That Strengthens Each Family Member, Chris L. Porter, Nancy B. Rollins

Marriage and Families

No abstract provided.

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Phishing Warden: Enhancing Content-Triggered Trust Negotiation To Prevent Phishing Attacks, James Presley Henshaw Jun 2005

Phishing Warden: Enhancing Content-Triggered Trust Negotiation To Prevent Phishing Attacks, James Presley Henshaw

Theses and Dissertations

Phishing attacks are spam e-mails that attempt to fool recipients into divulging their identifying information by posing as a message from a well known company and using that company's branding and logos. It is estimated that phishing attacks have cost bank and credit card customers $1.2 billion in the U.S. in 2003. Previous work, content-triggered trust negotiation (CTTN), filters Internet traffic for sensitive data, and prevents a user from disclosing sensitive information to an un-trusted server. However, existing CTTN implementations are vulnerable to client-side scripts that obfuscate any data the client's browser sends to the web server in order to …

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Forest Fire Monitoring With Multiple Small Uavs, David W. Casbeer, Randal W. Beard, Timothy W. Mclain, Sai-Ming Li, Raman K. Mehra Jun 2005

Forest Fire Monitoring With Multiple Small Uavs, David W. Casbeer, Randal W. Beard, Timothy W. Mclain, Sai-Ming Li, Raman K. Mehra

Faculty Publications

Frequent and detailed updates of the development of a forest fire are essential for effective and safe fire fighting. Since a forest fire is typically inaccessible by ground vehicles due to mountainous terrain, small Unmanned Air Vehicles (UAVs) are emerging as a promising solution to the problem of monitoring large forest fires. In this paper we present an effective path planning algorithm for a UAV utilizing infrared images that are collected on-board in realtime. In order to demonstrate the effectiveness of our path planning algorithm in realistic scenarios, we implemented the forest fire propagation model EMBYR to simulate the time …

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The Effect Of Reactor Configuration On No Conversion And Energy Consumption In Non-Thermal Plasma Parallel Tube Reactors, Morris D. Argyle, Gui-Bing Zhao, S.V.B. Janardhan Garikipati, Xudong Hu, Maciej Radosz Jun 2005

The Effect Of Reactor Configuration On No Conversion And Energy Consumption In Non-Thermal Plasma Parallel Tube Reactors, Morris D. Argyle, Gui-Bing Zhao, S.V.B. Janardhan Garikipati, Xudong Hu, Maciej Radosz

Faculty Publications

This work shows that the configuration of a pulsed corona discharge reactor strongly affects the rate of electron collision reactions. Experiments involving the decomposition of NO in N2 were performed in a reactor in which the number or parallel reactor tubes varied from 1 to 10 at a constant pressure of 147.6 kPa and ambient temperature. A previously developed lumped model of the reactions accurately predicted the effects of varying the initial concentrations of NO (from 240ppm to 593ppm) and gas residence time (from 1.93 to 742 s). With an increasing number of parallel reactor tubes, the rate of the …

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A Scenario-Based Performance Evaluation Of Multicast Routing Protocols For Ad Hoc Networks, Manoj Pandey, Daniel Zappala Jun 2005

A Scenario-Based Performance Evaluation Of Multicast Routing Protocols For Ad Hoc Networks, Manoj Pandey, Daniel Zappala

Faculty Publications

Current ad hoc multicast routing protocols have been designed to build and maintain a tree or mesh in the face of a mobile environment, with fast reaction to network changes in order to minimize packet loss. However, the performance of these protocols has not been adequately examined under realistic scenarios. Existing performance studies generally use a single, simple mobility model, with low density and often very low traffic rates. In this paper we explore the performance of ad hoc multicast routing protocols under scenarios that include realistic mobility patterns, high density and high traffic load. We use these scenarios to …

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Correspondence Expansion For Wide Baseline Stereo, Parris K. Egbert, Kevin L. Steele Jun 2005

Correspondence Expansion For Wide Baseline Stereo, Parris K. Egbert, Kevin L. Steele

Faculty Publications

We present a new method for generating large numbers of accurate point correspondences between two wide baseline images. This is important for structure-from-motion algorithms, which rely on many correct matches to reduce error in the derived geometric structure. Given a small initial correspondence set we iteratively expand the set with nearby points exhibiting strong affine correlation, and then we constrain the set to an epipolar geometry using RANSAC. A key point to our algorithm is to allow a high error tolerance in the constraint, allowing the correspondence set to expand into many areas of an image before applying a lower …

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Active Contours Using A Constraint-Based Implicit Representation, Weiming Liu, Bryan S. Morse, Kalpathi Subramanian, Terry S. Yoo Jun 2005

Active Contours Using A Constraint-Based Implicit Representation, Weiming Liu, Bryan S. Morse, Kalpathi Subramanian, Terry S. Yoo

Faculty Publications

We present a new constraint-based implicit active contour, which shares desirable properties of both parametric and implicit active contours. Like parametric approaches, their representation is compact and can be manipulated interactively. Like other implicit approaches, they can naturally adapt to non-simple topologies. Unlike implicit approaches using level-set methods, representation of the contour does not require a dense mesh. Instead, it is based on specified on-curve and off-curve constraints, which are interpolated using radial basis functions. These constraints are evolved according to specified forces drawn from the relevant literature of both parametric and implicit approaches. This new type of active contour …

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Microparticle Influenced Electroosmotic Flow, John M. Young May 2005

Microparticle Influenced Electroosmotic Flow, John M. Young

Theses and Dissertations

The influence of microparticles on electroosmotic flow was investigated experimentally and numerically. Experiments were conducted using four different particle types of varying chemical composition, surface charge and polarity. Each particle type was tested at five different volume fractions ranging from 0.001 – 0.025. With a constant applied electric field, positively charged particles enhanced the electroosmotic flow by as much as 850%. The enhancement depended on particle composition, size and concentration. For negatively charged particles, the bulk electroosmotic flow was retarded with the largest reductions being 35%. This occurred for the greatest negative paricle concentration studied. A final experimental study utilizing …

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Erratum: Computing The M = 1 Diocotron Frequency Via An Equilibrium Calculation In Non-Neutral Plasmas, Ross L. Spencer May 2005

Erratum: Computing The M = 1 Diocotron Frequency Via An Equilibrium Calculation In Non-Neutral Plasmas, Ross L. Spencer

Faculty Publications

Equation 14 in this paper contains errors.

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The Lie Symmetries Of A Few Classes Of Harmonic Functions, Willis L. Petersen May 2005

The Lie Symmetries Of A Few Classes Of Harmonic Functions, Willis L. Petersen

Theses and Dissertations

In a differential geometry setting, we can analyze the solutions to systems of differential equations in such a way as to allow us to derive entire classes of solutions from any given solution. This process involves calculating the Lie symmetries of a system of equations and looking at the resulting transformations. In this paper we will give a general background of the theory necessary to develop the ideas of working in the jet space of a given system of equations, applying this theory to harmonic functions in the complex plane. We will consider harmonic functions in general, harmonic functions with …

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Sound Quality Analysis Of Sewing Machines, James J. Chatterley May 2005

Sound Quality Analysis Of Sewing Machines, James J. Chatterley

Theses and Dissertations

Sound quality analysis is a tool designed to help determine customer preferences, which can be used to help the designer improve product quality. Many industries desire to know how the consuming public perceives their product, as this affects the product life and success. This research investigates which of the six sewing machines provided by Viking Sewing Machine Group (VSM group) consumers find most acoustically appealing. The sound quality analysis methods used include both jury based listening tests and quantitative sound quality metrics from empirical equations. The results from both methods are completely independent and are shown to have a very …

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An Improved Music Model For Gibbsite, Scott Christian Mitchell May 2005

An Improved Music Model For Gibbsite, Scott Christian Mitchell

Theses and Dissertations

Several recent studies that have proposed MUSIC models for gibbsite surfaces have purported to achieve a very good fit with potentiometric titration data. However, in order to achieve such results, several significant parameters, such as the number of surface sites, site densities, and pKa values were sometimes re-introduced in the model as fitted parameters, and physically unrealistic modeling assumptions were sometimes used. In addition, recent evidence supports the idea that some of the gibbsite potentiometric titration data from these studies may be unreliable. In order to re-interpret the potentiometric titration data, we used several recently published methods. In order to …

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Determining The Optimum Number Of Increments In Composite Sampling, John Ellis Hathaway May 2005

Determining The Optimum Number Of Increments In Composite Sampling, John Ellis Hathaway

Theses and Dissertations

Composite sampling can be more cost effective than simple random sampling. This paper considers how to determine the optimum number of increments to use in composite sampling. Composite sampling terminology and theory are outlined and a model is developed which accounts for different sources of variation in compositing and data analysis. This model is used to define and understand the process of determining the optimum number of increments that should be used in forming a composite. The blending variance is shown to have a smaller range of possible values than previously reported when estimating the number of increments in a …

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Evaluation Of Paleo-Climate For The Boise Area, Idaho, From The Last Glacial Maximum To The Present Based On Delta 2h And Delta 18o Groundwater Composition, Melissa Eileen Schlegel May 2005

Evaluation Of Paleo-Climate For The Boise Area, Idaho, From The Last Glacial Maximum To The Present Based On Delta 2h And Delta 18o Groundwater Composition, Melissa Eileen Schlegel

Theses and Dissertations

There are four distinguishable groundwater systems in the Boise area, Idaho, U.S.A., identified as modern batholith, thermal batholith, Boise frontal fault, and Nampa-Caldwell systems (Figure 1). Modern batholith and thermal batholith groundwaters are located in Tertiary to Cretaceous aged granites and granodiorites of the Atlanta lobe of the Idaho Batholith. The frontal fault system near Boise, ID defines the southeastern edge of the Idaho Batholith, and divides the batholith from the western Snake River Plain. The Nampa-Caldwell system is in the volcanic, fluvial and pluvial sediments of the western Snake River Plain. Groundwater ages for these systems are modern, 5-15 …

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Hopf Bifurcations And Horseshoes Especially Applied To The Brusselator, Steven R. Jones May 2005

Hopf Bifurcations And Horseshoes Especially Applied To The Brusselator, Steven R. Jones

Theses and Dissertations

In this paper we explore bifurcations, in particular the Hopf bifurcation. We study this especially in connection with the Brusselator, which is a model of certain chemical reaction-diffusion systems. After a thorough exploration of what a bifurcation is and what classifications there are, we give graphic representations of an occurring Hopf bifurcation in the Brusselator. When an additional forcing term is added, behavior changes dramatically. This includes the introduction of a horseshoe in the time map as well as a strange attractor in the system.

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Development Of A Five-Axis Machining Algorithm In Flat End Mill Roughing, Michael Blaine Thompson May 2005

Development Of A Five-Axis Machining Algorithm In Flat End Mill Roughing, Michael Blaine Thompson

Theses and Dissertations

To further the research done in machining complex surfaces, Jensen [1993] developed an algorithm that matches the normal curvature at a point along the surface with the resultant radius formed by tilting a standard flat end mill. The algorithm called Curvature Matched Machining (CM2) is faster and more efficient than conventional three-axis machining [Jensen 1993, Simpson 1995 & Kitchen 1996]. Despite the successes of CM2 there are still many areas available for research. Consider the machining of a mold or die. The complex nature of a mold requires at least 20-30 weeks of lead time. Of those 20-30 weeks 50% …

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Development And Application Of A New Modeling Technique For Production Control Schemes In Manufacturing Systems, Bashar Hafez Sader May 2005

Development And Application Of A New Modeling Technique For Production Control Schemes In Manufacturing Systems, Bashar Hafez Sader

Theses and Dissertations

This dissertation presents dynamic system models of continuous manufacturing systems based on analogies with electrical systems. The developed modeling technique has the capability to explicitly specify production control schemes including control points, material and information flow paths, and logical operations. The model provides standard graphical representations and governing equations to describe both the steady state and transient responses of continuous manufacturing systems. For deterministic systems, these equations can be solved to get closed-form solutions. For stochastic systems, numerical solutions can be obtained for any probabilistic distribution. The electrical analogs provide an excellent tool to model control signals and logical operations. …

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Mapping And Kinematic Structural Analysis Of The Deep Creek Fault Zone, South Flank Of The Uinta Mountains, Near Vernal, Utah, David A. Haddox May 2005

Mapping And Kinematic Structural Analysis Of The Deep Creek Fault Zone, South Flank Of The Uinta Mountains, Near Vernal, Utah, David A. Haddox

Theses and Dissertations

The geology along the southern flank of the Uinta Mountains, located north of Vernal, Utah, has been mapped at the 7.5' scale within two quadrangles: the Dry Fork and Steinaker Reservoir Quadrangles. Ambiguities dealing with stratigraphy, structural geology, and geohazards are currently being addressed as a result of this and other mapping projects in the vicinity. The geologic units in the area range in age from Mississippian to Late Cretaceous and include Uinta-sourced Tertiary units. Brief unit descriptions are provided for each of the units exposed in the map area. The main structural influence on the rocks within the area …

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Geochronology Of Hemphillian-Blancan Aged Strata, Guanajuato, Mexico, And Implications For Timing Of The Great American Biotic Interchange, Bart J. Kowallis, John J. Flynn, Clarita Nunez, Oscar Carranza-Castaneda, Wade E. Miller, Carl C. Swisher Iii, Everett Lindsay May 2005

Geochronology Of Hemphillian-Blancan Aged Strata, Guanajuato, Mexico, And Implications For Timing Of The Great American Biotic Interchange, Bart J. Kowallis, John J. Flynn, Clarita Nunez, Oscar Carranza-Castaneda, Wade E. Miller, Carl C. Swisher Iii, Everett Lindsay

Faculty Publications

We present new geochronologic magnetostratigraphy, fission-track and 40Ar/39Ar radioisotopic dates, biostratigraphy)bdata constraining the age of three separate sequences and a composite section from Guanajuato, Mexico. Those data make this one of the most complete and precisely age-calibrated sequences in North America spanning the Hemphillian/Blancan North American Land Mammal “Age” (NALMA) boundary interval, and the data further constrain the timing and pattern of the Great American Biotic Interchange (GABI). In total, 196 samples (77 sites) were used to construct the magnetic polarity stratigraphies, with eight fission-track analyses and four new 40Ar/39Ar radioisotopic dates. The sections sampled are possibly latest Miocene to …

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The Effect Of Inharmonic Partials On Pitch Of Piano Tones, Brian E. Anderson, William J. Strong Apr 2005

The Effect Of Inharmonic Partials On Pitch Of Piano Tones, Brian E. Anderson, William J. Strong

Faculty Publications

Piano tones have partials whose frequencies are sharp relative to harmonic values. A listening test was conducted to determine the effect of inharmonicity on pitch for piano tones in the lowest three octaves of a piano. Nine real tones from the lowest three octaves of a piano were analyzed to obtain frequencies, relative amplitudes, and decay rates of their partials. Synthetic inharmonic tones were produced from these results. Synthetic harmonic tones, each with a twelfth of a semitone increase in the fundamental, were also produced. A jury of 21 listeners matched the pitch of each synthetic inharmonic tone to one …

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Higher Radix Floating-Point Representations For Fpga-Based Arithmetic, Bryan Christopher Catanzaro Apr 2005

Higher Radix Floating-Point Representations For Fpga-Based Arithmetic, Bryan Christopher Catanzaro

Theses and Dissertations

Field Programmable Gate Arrays (FPGAs) are increasingly being used for high-throughput floating-point computation. It is forecasted that by 2009, FPGAs will provide an order of magnitude greater sustained floating-point throughput than conventional processors. FPGA implementations of floating-point operators have historically been designed to use binary floating-point representations, as do general purpose processors. Binary representations were chosen as the standard over three decades ago because they provide maximal numerical accuracy per bit of floating-point data. However, the unique nature of FPGA-based computation makes numerical accuracy per unit of FPGA resources a more important measure of the usefulness of a given floating-point …

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Establising A High-Frequency Standard Reference Sequence Stratigraphy, Sea-Level Curve, And Biostratigraphy For Morrowan Strata Of The Lower Absaroka I Time Slice Based Upon The Bird Spring Formation, Arrow Canyon, Nevada, Kristen Phelps Briggs Apr 2005

Establising A High-Frequency Standard Reference Sequence Stratigraphy, Sea-Level Curve, And Biostratigraphy For Morrowan Strata Of The Lower Absaroka I Time Slice Based Upon The Bird Spring Formation, Arrow Canyon, Nevada, Kristen Phelps Briggs

Theses and Dissertations

For the same reasons which prompted its ratification in 1990 as the Global Stratotype Section and Point for the Mid-Carboniferous boundary, namely, section completeness, abundant fossils, and excellent exposure, the Morrowan Arrow Canyon Bird Spring strata is recommended as a candidate standard sequence stratigraphic reference for the Morrowan portion of the Lower Absaroka I supersequence. The stratigraphic architecture of Morrowan strata in Arrow Canyon was largely controlled by high-amplitude (100-m), high-frequency sea-level changes. Outcrop data and facies stacking patterns define 59 fifth-order fundamental cycles. These fundamental cycles stack into ten third-order sequences with an average duration of 320 ka. Changes …

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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 …

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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 …

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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 …

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