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An Acoustical Analysis Of Domes Coupled To Rooms, With Special Application To The Darussholah Mosque, In East Java, Indonesia, Sentagi Sesotya Utami Aug 2005

An Acoustical Analysis Of Domes Coupled To Rooms, With Special Application To The Darussholah Mosque, In East Java, Indonesia, Sentagi Sesotya Utami

Theses and Dissertations

Concave surfaces are often considered to be detrimental or precarious in room acoustics, especially because of the impact they have on the distribution of sound energy. However, it is often difficult to avoid such surfaces in buildings with specific architectural functions. A primary example of this involves mosques, which are sacred places of worship for Muslims. In keeping with the Islamic architectural style, most mosques incorporate a symbolic centralized domed ceiling as part of their room structures. These domes are open on the bottom and coupled to the acoustic spaces below. In many cases, the lower spaces may be idealized …

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Effects Of Pressure On Coal Pyrolysis At High Heating Rates And Char Combustion, Dong Zeng Aug 2005

Effects Of Pressure On Coal Pyrolysis At High Heating Rates And Char Combustion, Dong Zeng

Theses and Dissertations

Clean coal technologies are now becoming popular because of their high efficiencies and minimal environmental impact. Higher operating pressures have been applied to clean coal technologies. The effect of pressure on coal pyrolysis and char combustion has been extensively studied but still remains to be further explored. The objective of this project was to characterize high pressure, high heating rate coal pyrolysis and char combustion, with emphasis on improving coal/char high pressure combustion models. A flat-flame burner was used in a high pressure laminar flow facility to conduct high temperature, high heating rate pyrolysis and combustion experiments for four coals. …

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A Method For Characterizing The Properties Of Industrial Foams, Shaun M. Salisbury Aug 2005

A Method For Characterizing The Properties Of Industrial Foams, Shaun M. Salisbury

Theses and Dissertations

Assessing the effect of foam layers on transport phenomena is of significant interest in many industries, so a method for predicting foam layer properties has been developed. A model of the propagation of radiation from an amplitude-modulated laser beam through a non-absorbing foam layer has been developed using diffusion theory. Measurements predicted by diffusion theory were compared to results generated using Monte Carlo methods for a variety of foam layer properties in both the time-domain and the frequency-domain. The properties that were varied include the layer thickness, the scattering coefficient, and the asymmetry parameter. Layer thicknesses between 8.5 mm and …

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Estimating The Discrepancy Between Computer Model Data And Field Data: Modeling Techniques For Deterministic And Stochastic Computer Simulators, Emily Joy Dastrup Aug 2005

Estimating The Discrepancy Between Computer Model Data And Field Data: Modeling Techniques For Deterministic And Stochastic Computer Simulators, Emily Joy Dastrup

Theses and Dissertations

Computer models have become useful research tools in many disciplines. In many cases a researcher has access to data from a computer simulator and from a physical system. This research discusses Bayesian models that allow for the estimation of the discrepancy between the two data sources. We fit two models to data in the field of electrical engineering. Using this data we illustrate ways of modeling both a deterministic and a stochastic simulator when specific parametric assumptions can be made about the discrepancy term.

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Exploration Of Lip Shape Measures And Their Association With Tongue Contact Patterns, Jessica Lynn Wagner Aug 2005

Exploration Of Lip Shape Measures And Their Association With Tongue Contact Patterns, Jessica Lynn Wagner

Theses and Dissertations

A variety of tools and techniques have been developed to measure the movements of the vocal tract, specifically of the tongue and lips. In recent years, computer technology has allowed for extensive exploration of these precise movements and for the development of speech recognition systems. However, there has been relatively little work on the combination of visible facial movements and internal articulatory activity. In this study, two different technologies were used to explore the internal and external movements of speech production in eight speakers: palatometry quantified tongue contact patterns and computerized video image analysis was used to derive lip shape …

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Piecing Together The Triassic/Jurassic Stratigraphy Along The South Flank Of The Uinta Mountains, Northeast Utah: A Stratigraphic Analysis Of The Bell Springs Member Of The Nugget Sandstone, Paul H. Jensen Jr. Aug 2005

Piecing Together The Triassic/Jurassic Stratigraphy Along The South Flank Of The Uinta Mountains, Northeast Utah: A Stratigraphic Analysis Of The Bell Springs Member Of The Nugget Sandstone, Paul H. Jensen Jr.

Theses and Dissertations

Nomenclature for the Upper Triassic and Lower Jurassic strata along the south flank of the Uinta Mountains has been somewhat confusing because of the position of the study area between southern Wyoming, where one set of names is used, and central/southern Utah where a different set of formation names is used. The Nugget Sandstone or Glen Canyon Sandstone of the eastern Uinta Mountains overlies the Upper Triassic Popo Agie or Chinle Formation. The nature of the contact between these two formations is unclear both in stratigraphic location and conformability. The Chinle Formation consists, in ascending order, of the Gartra Member, …

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Task Similarity Measures For Transfer In Reinforcement Learning Task Libraries, James Carroll, Kevin Seppi Aug 2005

Task Similarity Measures For Transfer In Reinforcement Learning Task Libraries, James Carroll, Kevin Seppi

Faculty Publications

Recent research in task transfer and task clustering has necessitated the need for task similarity measures in reinforcement learning. Determining task similarity is necessary for selective transfer where only information from relevant tasks and portions of a task are transferred. Which task similarity measure to use is not immediately obvious. It can be shown that no single task similarity measure is uniformly superior. The optimal task similarity measure is dependent upon the task transfer method being employed. We define similarity in terms of tasks, and propose several possible task similarity measures, dT, dp, dQ, and dR which are based on …

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Edge Inference For Image Interpolation, Bryan S. Morse, Neil Toronto, Dan A. Ventura Aug 2005

Edge Inference For Image Interpolation, Bryan S. Morse, Neil Toronto, Dan A. Ventura

Faculty Publications

Image interpolation algorithms try to fit a function to a matrix of samples in a "natural-looking" way. This paper presents edge inference, an algorithm that does this by mixing neural network regression with standard image interpolation techniques. Results on gray level images are presented, and it is demonstrated that edge inference is capable of producing sharp, natural-looking results. A technique for reintroducing noise is given, and it is shown that, with noise added using a bicubic interpolant, edge inference can be regarded as a generalization of bicubic interpolation. Extension into RGB color space and additional applications of the algorithm are …

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Model Checking For E-Business Control And Assurance, Bonnie B. Anderson, James V. Hansen, Paul B. Lowry, Scott L. Summers Aug 2005

Model Checking For E-Business Control And Assurance, Bonnie B. Anderson, James V. Hansen, Paul B. Lowry, Scott L. Summers

Faculty Publications

Model checking is a promising technique for the verification of complex software systems. As the use of the Internet for conducting e-business extends the reach of many organizations, well-designed software becomes the foundation of reliable implementation of e-business processes. These distributed, electronic methods of conducting transactions place reliance on the control structures embedded in the transaction processes. Deficiencies in control structures of processes that support e-business can lead to loss of physical assets, digital assets, money, and consumer confidence. Yet, assessing the reliability of e-business processes is complex and time-consuming. This paper explicates how model-checking technology can aid in the …

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Performance Of Aic-Selected Spatial Covariance Structures For Fmri Data, David A. Stromberg Jul 2005

Performance Of Aic-Selected Spatial Covariance Structures For Fmri Data, David A. Stromberg

Theses and Dissertations

FMRI datasets allow scientists to assess functionality of the brain by measuring the response of blood flow to a stimulus. Since the responses from neighboring locations within the brain are correlated, simple linear models that assume independence of measurements across locations are inadequate. Mixed models can be used to model the spatial correlation between observations, however selecting the correct covariance structure is difficult. Information criteria, such as AIC are often used to choose among covariance structures. Once the covariance structure is selected, significance tests can be used to determine if a region of interest within the brain is significantly active. …

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Modeling Global Warming Scenarios In Greenback Cutthroat Trout (Oncorhynchus Clarki Stomias) Streams: Implications For Species Recovery, Scott J. Cooney, Alan P. Covich, Paul M. Lukacs, Amy L. Harig, Kurt D. Fausch Jul 2005

Modeling Global Warming Scenarios In Greenback Cutthroat Trout (Oncorhynchus Clarki Stomias) Streams: Implications For Species Recovery, Scott J. Cooney, Alan P. Covich, Paul M. Lukacs, Amy L. Harig, Kurt D. Fausch

Western North American Naturalist

Changes in global climate may exacerbate other anthropogenic stressors, accelerating the decline in distribution and abundance of rare species throughout the world. We examined the potential effects of a warming climate on the greenback cutthroat trout (Oncorhynchus clarki stomias), a resident salmonid that inhabits headwater streams of the central Rocky Mountains. Greenbacks are outcompeted at lower elevations by nonnative species of trout and currently are restricted to upper-elevation habitats where barriers to upstream migration by nonnatives are or have been established. We used likelihood-based techniques and information theoretics to select models predicting stream temperature changes for 10 streams …

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Detecting Similar Html Documents Using A Sentence-Based Copy Detection Approach, Rajiv Yerra Jul 2005

Detecting Similar Html Documents Using A Sentence-Based Copy Detection Approach, Rajiv Yerra

Theses and Dissertations

Web documents that are either partially or completely duplicated in content are easily found on the Internet these days. Not only these documents create redundant information on the Web, which take longer to filter unique information and cause additional storage space, but also they degrade the efficiency of Web information retrieval. In this thesis, we present a new approach for detecting similar (HTML)Web documents and evaluate its performance. To detect similar documents, we first apply our sentence-based copy detection approach to determine whether sentences in any two documents should be treated as the same or different according to the degrees …

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The Impact Of Antenna And Rf System Characteristics On Mimo System Capacity, Matthew Leon Morris Jul 2005

The Impact Of Antenna And Rf System Characteristics On Mimo System Capacity, Matthew Leon Morris

Theses and Dissertations

The recent growth in demand for wireless services coupled with the limited spectrum available for these services has spawned new efforts to increase the spectral efficiency of wireless links. Recent research has shown that in multipath propagation environments, the spatial characteristics of the propagation channel can be exploited to increase spectral efficiency through the use of multiple antennas at the transmitting and receiving nodes. Such multiple-input multiple-output (MIMO) systems show promise for dramatic performance gains over their single-antenna counterparts. However, MIMO system performance is influenced by many different factors. Antenna array configuration directly contributes to MIMO system performance. The ability …

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A Modified Poisson–Boltzmann Analysis Of The Capacitance Behavior Of The Electric Double Layer At Low Temperatures, Douglas Henderson, L. B. Bhuiyan, C. W. Outhwaite Jul 2005

A Modified Poisson–Boltzmann Analysis Of The Capacitance Behavior Of The Electric Double Layer At Low Temperatures, Douglas Henderson, L. B. Bhuiyan, C. W. Outhwaite

Faculty Publications

The modified Poisson–Boltzmann theory is used to analyze the anomalous behavior of the electric double layer capacitance for small surface charge at low temperatures and densities. Good agreement is found with simulation and recent density-functional theory results. Negative adsorption is also found in line with theory and simulation. An unsatisfactory feature is the relatively poor structure in this region due to the inherent approximations in the theory. This feature is unimportant in relation to the capacitance results but has implications when calculating adsorption properties.

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Constraint-Based Interpolation, Daniel David Goggins Jul 2005

Constraint-Based Interpolation, Daniel David Goggins

Theses and Dissertations

Image reconstruction is the process of converting a sampled image into a continuous one prior to transformation and resampling. This reconstruction can be more accurate if two things are known: the process by which the sampled image was obtained and the general characteristics of the original image. We present a new reconstruction algorithm known as Constraint-Based Interpolation, which estimates the sampling functions found in cameras and analyzes properties of real world images in order to produce quality real-world image magnifications. To accomplish this, Constraint-Based Interpolation uses a sensor model that pushes the pixels in an interpolation to more closely match …

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The Perceptions Of High School Physical Educators On The Benefits Of Block Scheduling In The State Of Utah, Marilyn Miller Jul 2005

The Perceptions Of High School Physical Educators On The Benefits Of Block Scheduling In The State Of Utah, Marilyn Miller

Theses and Dissertations

The purpose of this research was to examine the extent to which the block schedule is being used in Utah high school physical education, and determine teacher's perceptions of block scheduling in teaching physical education. Block scheduling is a new and more efficient way of organizing the school day. NASPE has found the following positive effects in block scheduling: a better learning environment, more access to stronger curriculum, detailed instruction and demonstrations, and more variety in assessment (NASPE, 2000). Although there were several different forms of the block schedule reported, it appears that a majority of physical educators have discovered …

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Hard-Sphere Radial Distribution Function Again, Andrij Trokhymchuk, Douglas Henderson, Ivo Nezbeda, Jan Jirsak Jul 2005

Hard-Sphere Radial Distribution Function Again, Andrij Trokhymchuk, Douglas Henderson, Ivo Nezbeda, Jan Jirsak

Faculty Publications

A theoretically based closed-form analytical equation for the radial distribution function, g(r), of a fluid of hard spheres is presented and used to obtain an accurate analytic representation. The method makes use of an analytic expression for the short- and long-range behaviors of g(r), both obtained from the Percus-Yevick equation, in combination with the thermodynamic consistency constraint. Physical arguments then leave only three parameters in the equation of g(r) that are to be solved numerically, whereas all remaining ones are taken from the analytical solution of the Percus-Yevick equation.

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Biofilm Removal Using Bubbles And Sound, Michael R. Parini Jul 2005

Biofilm Removal Using Bubbles And Sound, Michael R. Parini

Theses and Dissertations

Bacteria in biofilms adhere well to surfaces and are quite difficult to remove. Oral plaque is one example of a biofilm. Many researchers have studied ways to remove plaque and bacteria from surfaces. It has been found that the passage of a bubble across a surface to which bacteria has adhered can remove the bacteria from the surface. Biofilms of Streptococcus mutans were grown on glass coverslips as a simple model for oral plaque. The coverslips were mounted in a Plexiglas chamber filled with artificial saliva. A bubble stream was directed at the mounted biofilm. The velocity, gas fraction, median …

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Experimental And Numerical Investigation Of Tool Heating During Friction Stir Welding, Joshua L. Covington Jul 2005

Experimental And Numerical Investigation Of Tool Heating During Friction Stir Welding, Joshua L. Covington

Theses and Dissertations

The heat input to the tool has been investigated for friction stir welding (FSW) of aluminum alloy AL 7075-T7351 over a wide range of process operating parameters using a combined experimental/numerical approach. In a statistical Design of Experiments fashion, 54 experimental welds (bead-on-plate) were performed at 27 different parameter combinations. Measured outputs during each of the welds included forces in all three coordinate directions and internal temperature of the rotating tool at three locations near the tool/workpiece interface. The heat input to the tool was also identified for each weld using infrared imaging temperature measurement techniques and the portion of …

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Cache Characterization And Performance Studies Using Locality Surfaces, Elizabeth Schreiner Sorenson Jul 2005

Cache Characterization And Performance Studies Using Locality Surfaces, Elizabeth Schreiner Sorenson

Theses and Dissertations

Today's processors commonly use caches to help overcome the disparity between processor and main memory speeds. Due to the principle of locality, most of the processor's requests for data are satisfied by the fast cache memory, resulting in a signficant performance improvement. Methods for evaluating workloads and caches in terms of locality are valuable for cache design. In this dissertation, we present a locality surface which displays both temporal and spatial locality on one three-dimensional graph. We provide a solid, mathematical description of locality data and equations for visualization. We then use the locality surface to examine the locality of …

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Development Of A Model For The Kinetics And Mechanism Of Nitrogenase, Phillip E. Wilson Jul 2005

Development Of A Model For The Kinetics And Mechanism Of Nitrogenase, Phillip E. Wilson

Theses and Dissertations

Nitrogenase has a central role in the global nitrogen cycle as the enzyme that catalyzes the reduction of atmospheric N2 to NH3. Fixed nitrogen is generally limiting in the environment and in agriculture, so nitrogenase has received much attention as an alternative to nitrogen fertilizers. Characterizing the mechanism of nitrogenase is the goal of this work. The molybdenum nitrogenase enzyme system is comprised of the MoFe protein and the Fe protein. Interactions between these proteins and nucleotides are crucial to catalysis. An important approach to characterize these interactions is to correlate the kinetics of nitrogenase catalysis to a mechanism based …

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Angiotensin Ii-Mediated Regulation Of The Human Angiotensin Ii Type 1 Receptor Gene, Xylophone Vijai Aasee Victor Jul 2005

Angiotensin Ii-Mediated Regulation Of The Human Angiotensin Ii Type 1 Receptor Gene, Xylophone Vijai Aasee Victor

Theses and Dissertations

The physiological responses of angiotensin II (Ang II) are mediated across the cell membrane through the angiotensin II type 1 receptor (AT1R), a heptahelical membrane protein coupled to trimeric G-proteins on the cytosolic side. AT1R on binding its ligand, Ang II, leads to downregulation of cell-surface receptor and also its mRNA. We have investigated whether the 3'- and 5'-untranslated regions of the human AT1R mRNA mediate the degradation of hAT1R mRNA by post-transcriptional mechanisms in human adrenocortical carcinoma cell line (H295R cells). Protein kinase C (PKC) activator, phorbol-12-myristate-13-acetate (PMA), showed that the downregulation of hAT1R mRNA is mediated by the …

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Annual Exceedance Probability Analysis, Masako Amai Gardner Jul 2005

Annual Exceedance Probability Analysis, Masako Amai Gardner

Theses and Dissertations

Annual Exceedance Probability (AEP) is the method used by U.S. Army Corps of Engineers (USACE) to determine the probability of flooding caused by the failure of a levee or other flood control structure. This method shows the probability of flooding only at one particular location at a time. In order to overcome the limitation of AEP, a new method of studying flood probability, called an AEP map, was presented. By using hydrologic and hydraulic modeling software, an AEP map can be created to determine and visualize the spatial distribution of the probability of flooding. An AEP map represents a continuous …

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An Examination Of The Role Of Writing In Mathematics Instruction, Amy Jeppsen Jul 2005

An Examination Of The Role Of Writing In Mathematics Instruction, Amy Jeppsen

Theses and Dissertations

This study uses qualitative methods to investigate the use of writing in a content course for elementary education majors in which writing was considered an important part of mathematical learning. The study differs from previous studies by investigating the role of writing in the everyday instructional activities, rather than investigating writing as a separate mathematical activity. An analysis of the instruction and class discussions that took place in this class reveals that components of writing that were addressed implicitly and explicitly in classroom instruction were developed simultaneously with conceptual understanding, suggesting a much stronger and more integral relationship between writing …

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Elevation, Longitudinal Profile, And Schmidt Hammer Analysis Of Strath Terraces Through Capitol Reef National Park, Utah: Bedrock Channel Response To Climate Forcing?, James L. Eddleman Jul 2005

Elevation, Longitudinal Profile, And Schmidt Hammer Analysis Of Strath Terraces Through Capitol Reef National Park, Utah: Bedrock Channel Response To Climate Forcing?, James L. Eddleman

Theses and Dissertations

Elevation, longitudinal profile, and Schmidt hammer data indicate that strath terraces (specifically the lower elevation terraces) mapped in the Fremont River drainage of Capitol Reef National Park are correlative to the terraces of the smaller Pleasant Creek drainage located approximately ten miles to the south. This correlation suggests that drainage development in this area of the Colorado Plateau was strongly dependent upon a regional-scale forcing mechanism (e.g. climate) rather than strictly independent basin-scale processes. Elevations of mapped strath terraces and their associated black volcanic boulder deposits were calculated from geologic maps, Digital Elevation Models (DEM), and Digital Orthophoto Quadrangles of …

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Effects Of Hurricane Fault Architecture On Groundwater Flow In The Timpoweap Canyon Of Southwestern, Utah, Sarah J. Dutson Jul 2005

Effects Of Hurricane Fault Architecture On Groundwater Flow In The Timpoweap Canyon Of Southwestern, Utah, Sarah J. Dutson

Theses and Dissertations

Hydrogeologically important features of fault zones include undamaged country rock, the damage zone, and the core zone. Fault cores generally have low porosity and permeability, and often act as a barrier to groundwater flow. The damage zone, by contrast, consists of small faults and fracture networks, which can act as conduits. Timpoweap Canyon near Hurricane, Utah has superb exposures of the fault core and damage zone of the Hurricane Fault. Also within the canyon, springs discharge from the damage zone into the Virgin River, providing an ideal natural laboratory for the study of groundwater discharge from a fault zone. The …

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Perceived Impact Of The No Child Left Behind Act Of 2001 On Paraprofessionals, Heather Goodwin Nelson Jul 2005

Perceived Impact Of The No Child Left Behind Act Of 2001 On Paraprofessionals, Heather Goodwin Nelson

Theses and Dissertations

Using the states' paraprofessional requirements, this study explored the effects of the No Child Left Behind Act of 2001 (NCLB) on the paraprofessionals' ability to assist in instruction as seen through the perceptions of paraprofessional and teacher teams. The literature review discloses data regarding the implementation of NCLB paraprofessional requirements into the accountability plans of the 50 states and the District of Columbia. Tables synthesize the assessments used by states to meet NCLB paraprofessional requirements. The Council for Exceptional Children performance-based standards for paraeducators provides the framework for the development of two survey instruments, which measured the perceptions of paraprofessionals …

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Fraction Multiplication And Division Image Change In Pre-Service Elementary Teachers, Jennifer J. Cluff Jul 2005

Fraction Multiplication And Division Image Change In Pre-Service Elementary Teachers, Jennifer J. Cluff

Theses and Dissertations

This study investigated three pre-service elementary teachers' understanding of fractions and fraction multiplication and division. The motivation for this study was lack of conceptual understanding of fractions and fraction multiplication and division. Pre-service elementary teachers were chosen because teachers are the conduit of information for their students. The subjects were followed through the fractions unit in a mathematics methods course for pre-service elementary teachers at Brigham Young University. Each subject volunteered to participate and were interviewed and videotaped throughout the study, and they also provided copies of all work done in the fractions unit in the course. The data is …

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Establishing Public Confidence In The Viability Of Fingerprint Biometric Technology, Nathan Alan Green Jul 2005

Establishing Public Confidence In The Viability Of Fingerprint Biometric Technology, Nathan Alan Green

Theses and Dissertations

The most common personal authentication techniques used for identity management employ a secret PIN or password that must be remembered. The challenge, for a given user, is that a multitude of such codes must be recalled over the course of the day for transactions involving distinct computer applications. Password mania prevails. Fingerprint biometric technology is an ideal alternate solution to this password recall problem. In spite of their availability for nearly thirty years, fingerprint biometric systems still remain uncommon in public sectors of industry such as education, government, and technology. Technology has improved sufficiently that false acceptance and rejection rates …

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Representations For Understanding The Stern-Gerlach Effect, Jared R. Stenson Jul 2005

Representations For Understanding The Stern-Gerlach Effect, Jared R. Stenson

Theses and Dissertations

The traditional explanation of the Stern-Gerlach effect carries with it several very subtle assumptions and approximations. We point out the degree to which this fact has affected the way we practice and interpret modern physics. In order to gain a more complete understanding of the Stern-Gerlach effect beyond the standard approximations and assumptions it typically carries, we introduce the inhomogeneous Stern-Gerlach effect in which the strong uniform field component is removed. This change allows us to easily identify precession as a critical concept. It also provides us with a means by which to study precession and analyze it critically. By …

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