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2007

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The Influence Of Discourse And Journal Writing On Second Graders' Acquisition Of Multidigit Addition Concepts, Elizabeth Hensley Jan 2007

The Influence Of Discourse And Journal Writing On Second Graders' Acquisition Of Multidigit Addition Concepts, Elizabeth Hensley

Electronic Theses and Dissertations

The purpose of this study was to examine how second graders use writing and language when they are learning to add multidigit numbers in mathematics class. Second grade students were taught addition conceptually with a focus on sharing their strategies and thought processes with each other during the mathematics lesson. Two social norms were established with students so that sharing information and asking for clarity when they did not understand would be natural and expected. Students kept a daily mathematics journal to answer the class's Problems of the Day. Patterns found in student journals indicated three stages of multidigit learning. …

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On Optimality Of Bayesian Testimation In The Normal Means Problem, Felix Abramovich, Vadim Grinshtein, Marianna Pensky Jan 2007

On Optimality Of Bayesian Testimation In The Normal Means Problem, Felix Abramovich, Vadim Grinshtein, Marianna Pensky

Faculty Bibliography 2000s

We consider a problem of recovering a high-dimensional vector mu observed in white noise, where the unknown vector g is assumed to be sparse. The objective of the paper is to develop a Bayesian formalism which gives rise to a family of l(0)-type penalties. The penalties are associated with various choices of the prior distributions pi(n)(center dot) on the number of nonzero entries of mu and, hence, are easy to interpret. The resulting Bayesian estimators lead to a general thresholding rule which accommodates many of the known thresholding and model selection procedures as particular cases corresponding to specific choices of …

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Voigt Spectral Profiles In Two-Photon Resonance Fluorescence, Moorad Alexanian, Subir K. Bose Jan 2007

Voigt Spectral Profiles In Two-Photon Resonance Fluorescence, Moorad Alexanian, Subir K. Bose

Faculty Bibliography 2000s

A recent work on two-photon fluorescence is extended by considering the pump field to be a coherent state, which represents a laser field operating well above threshold. The dynamical conditions are investigated under which the two-photon spectrum gives rise, in addition to a Lorentzian line shape at the pump frequency, to two Voigt spectral sideband profiles. Additional conditions are found under which the Voigt profile behaves like either a Gaussian or a Lorentzian line shape.

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A Bayesian Approach To Estimation And Testing In Time-Course Microarray Experiments, Claudia Angelini, Daniela De Canditiis, Margherita Mutarelli, Marianna Pensky Jan 2007

A Bayesian Approach To Estimation And Testing In Time-Course Microarray Experiments, Claudia Angelini, Daniela De Canditiis, Margherita Mutarelli, Marianna Pensky

Faculty Bibliography 2000s

The objective of the present paper is to develop a truly functional Bayesian method specifically designed for time series microarray data. The method allows one to identify differentially expressed genes in a time-course microarray experiment, to rank them and to estimate their expression profiles. Each gene expression profile is modeled as an expansion over some orthonormal basis, where the coefficients and the number of basis functions are estimated from the data. The proposed procedure deals successfully with various technical difficulties that arise in typical microarray experiments such as a small number of observations, non-uniform sampling intervals and missing or replicated …

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Analysis Of Global Geomagnetic Variability, V. Anh, Z. -G. Yu, J. A. Wanliss Jan 2007

Analysis Of Global Geomagnetic Variability, V. Anh, Z. -G. Yu, J. A. Wanliss

Faculty Bibliography 2000s

The orthogonal field components from global INTERMAGNET magnetometer stations are studied via multifractal detrended fluctuation analysis to determine whether there are clear and consistent regional patterns in the behavior of the fluctuations. There are three distinct scaling regimes in the qth-order fluctuation function for each of the 24 stations studied covering Southwest North America, Northeast North America, Central Europe, Northern Europe, Australasia and Asia. There is a consistent break point at time scale around 23 h for all stations. The scaling exponents of the second-order fluctuation functions reflect the regional character of the stations, and can be used for station …

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Self-Bending Of Dark And Gray Photorefractive Solitons, M. I. Carvalho, M. Facão, D. N. Christodoulides Jan 2007

Self-Bending Of Dark And Gray Photorefractive Solitons, M. I. Carvalho, M. Facão, D. N. Christodoulides

Faculty Bibliography 2000s

We investigate the effects of diffusion on the evolution of steady-state dark and gray spatial solitons in biased photorefractive media. Numerical integration of the nonlinear propagation equation shows that the soliton beams experience a modification of their initial trajectory, as well as a variation of their minimum intensity. This process is further studied using perturbation analysis, which predicts that the center of the optical beam moves along a parabolic trajectory and, moreover, that its minimum intensity varies linearly with the propagation distance, either increasing or decreasing depending on the sign of the initial transverse velocity. Relevant examples are provided.

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Decoupling Of Silicon Carbide Optical Sensor Response For Temperature And Pressure Measurements, A. Chakravarty, N. R. Quick, A. Kar Jan 2007

Decoupling Of Silicon Carbide Optical Sensor Response For Temperature And Pressure Measurements, A. Chakravarty, N. R. Quick, A. Kar

Faculty Bibliography 2000s

Single crystal silicon carbide is a chemically inert transparent material with superior oxidation-resistant properties at elevated temperatures compared to black polycrystalline silicon carbide substrates. These improved properties make crystalline silicon carbide a good optical sensor material for harsh environments such as combustion chambers and turbine systems. Interferometric optical sensors are orders of magnitude more sensitive than electrical sensors and are proposed for these applications. Silicon carbide itself behaves as a Fabry-Perot etalon eliminating the need for an external interferometer for any measurement using this silicon carbide as a sensor. The principle of the optical sensor in this study is the …

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Sharp Estimates On Minimum Travelling Wave Speed Of Reaction Diffusion Systems Modelling Autocatalysis, Xinfu Chen, Yuanwei Qi Jan 2007

Sharp Estimates On Minimum Travelling Wave Speed Of Reaction Diffusion Systems Modelling Autocatalysis, Xinfu Chen, Yuanwei Qi

Faculty Bibliography 2000s

This article studies propagating wave fronts in an isothermal chemical reaction A + 2B - > 3B involving two chemical species, a reactant A and an autocatalyst B, whose diffusion coefficients, D-A and D-B, are unequal due to different molecular weights and/or sizes. Explicit bounds v(*) and v* that depend on D-B/D-A are derived such that there is a unique travelling wave of every speed v > = v* and there does not exist any travelling wave of speed v < v*. New to the literature, it is shown that v(*) proportional to v* proportional to D-B/D-A when D-B = v(min). Estimates on v(min) significantly improve those of early works. The framework is built upon general isothermal autocatalytic chemical reactions A + nB - > (n + 1)B of arbitrary order n > = 1.

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Improved Residue Contact Prediction Using Support Vector Machines And A Large Feature Set, Jianlin Cheng, Pierre Baldi Jan 2007

Improved Residue Contact Prediction Using Support Vector Machines And A Large Feature Set, Jianlin Cheng, Pierre Baldi

Faculty Bibliography 2000s

Background: Predicting protein residue-residue contacts is an important 2D prediction task. It is useful for ab initio structure prediction and understanding protein folding. In spite of steady progress over the past decade, contact prediction remains still largely unsolved. Results: Here we develop a new contact map predictor (SVMcon) that uses support vector machines to predict medium- and long-range contacts. SVMcon integrates profiles, secondary structure, relative solvent accessibility, contact potentials, and other useful features. On the same test data set, SVMcon's accuracy is 4% higher than the latest version of the CMAPpro contact map predictor. SVMcon recently participated in the seventh …

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Elevated Soil Lead: Statistical Modeling And Apportionment Of Contributions From Lead-Based Paint And Leaded Gasoline, R. Dennis Cook, Liqiang Ni Jan 2007

Elevated Soil Lead: Statistical Modeling And Apportionment Of Contributions From Lead-Based Paint And Leaded Gasoline, R. Dennis Cook, Liqiang Ni

Faculty Bibliography 2000s

While it is widely accepted that lead-based paint and leaded gasoline are primary sources of elevated concentrations of lead in residential soils, conclusions regarding their relative contributions are mixed and generally study specific. We develop a novel nonlinear regression for soil lead concentrations over time. It is argued that this methodology provides useful insights into the partitioning of the average soil lead concentration by source and time over large residential areas. The methodology is Used to investigate soil lead concentrations from the 1987 Minnesota Lead Study and the 1990 National Lead Survey. Potential litigation issues are disscussed briefly.

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Accd6, A Member Of The Fas Ii Locus, Is A Functional Carboxyltransferase Subunit Of The Acyl-Coenzyme A Carboxylase In Mycobacterium Tuberculosis, Jaiyanth Daniel, Tae-Jin Oh, Chang-Muk Lee, Pappachan E. Kolattukudy Jan 2007

Accd6, A Member Of The Fas Ii Locus, Is A Functional Carboxyltransferase Subunit Of The Acyl-Coenzyme A Carboxylase In Mycobacterium Tuberculosis, Jaiyanth Daniel, Tae-Jin Oh, Chang-Muk Lee, Pappachan E. Kolattukudy

Faculty Bibliography 2000s

The Mycobacterium tuberculosis acyl-coenzyme A (CoA) carboxylases provide the building blocks for de novo fatty acid biosynthesis by fatty acid synthase I (FAS 1) and for the elongation of FAS I end products by the FAS 11 complex to produce meromycolic acids. The M. tuberculosis genome contains three biotin carboxylase subunits (AccA1 to -3) and six carboxyltransferase subunits (AccD1 to -6), with accD6 located in a genetic locus that contains members of the FAS 11 complex. We found by quantitative real-time PCR analysis that the transcripts of accA3, accD4, accD5, and accD6 are expressed at high levels during the exponential …

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Electrode Architecture In Tuning Room Temperature Sensing Kinetics Of Nanomicrointegrated Hydrogen Sensor, Sameer Deshpande, Sudipta Seal, Peng Zhang, Hyoung J. Cho, Nathan Posey Jan 2007

Electrode Architecture In Tuning Room Temperature Sensing Kinetics Of Nanomicrointegrated Hydrogen Sensor, Sameer Deshpande, Sudipta Seal, Peng Zhang, Hyoung J. Cho, Nathan Posey

Faculty Bibliography 2000s

A diffusion model is proposed for elucidating the effect of interelectrode distance modulation on conductance change of a nanomicrointegrated hydrogen sensor at room temperature. Both theoretical and experimental results showed a faster response upon exposure to hydrogen when sensor electrode gap was smaller. Also, a linear increase in the sensor sensitivity from 500 to 80 000 was observed on increasing the electrode spacing from 2 to 20 mu m. The improvement in sensitivity is attributed to the higher reactive sites available for the gaseous species to react on the sensor surface.

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Filtered Backprojection Inversion Of The Cone Beam Transform For A General Class Of Curves, Alexander Katsevich, Mikhail Kapralov Jan 2007

Filtered Backprojection Inversion Of The Cone Beam Transform For A General Class Of Curves, Alexander Katsevich, Mikhail Kapralov

Faculty Bibliography 2000s

We extend a cone beam transform inversion formula, proposed earlier for helices by one of the authors, to a general class of curves. The inversion formula remains efficient, because filtering is shift-invariant and is performed along a one-parametric family of lines. The conditions that describe the class are very natural. Curves C are smooth, without self-intersections, have positive curvature and torsion, do not bend too much, and do not admit lines which are tangent to C at one point and intersect C at another point. The notions of PI lines and PI segments are generalized, and their properties are studied. …

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An Initial Evaluation Of Mathpad(2): A Tool For Creating Dynamic Mathematical Illustrations, Joseph J. Laviola Jr. Jan 2007

An Initial Evaluation Of Mathpad(2): A Tool For Creating Dynamic Mathematical Illustrations, Joseph J. Laviola Jr.

Faculty Bibliography 2000s

MathPad(2) is a pen-based application prototype for creating mathematical sketches. Using a modeless gestural interface, it lets users make dynamic illustrations by associating handwritten mathematics with free-form drawings and provides a set of tools for graphing and evaluating mathematical expressions and solving equations. In this paper, we present the results of an initial evaluation of the MathPad(2) prototype, examining the user interface's intuitiveness and the application's perceived usefulness. Our evaluations are based on both performance and questionnaire results including first attempt gesture performance, interface recall tests, and surveys of user interface satisfaction and perceived usefulness. The results of our evaluation …

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A Structure Theorem For The Gromov-Witten Invariants Of Kahler Surfaces, Junho Lee, Thomas H. Parker Jan 2007

A Structure Theorem For The Gromov-Witten Invariants Of Kahler Surfaces, Junho Lee, Thomas H. Parker

Faculty Bibliography 2000s

We prove a structure theorem for the Gromov-Witten invariants of compact Kahler surfaces with geometric genus p(g) > 0. Under the technical assumption that there is a canonical divisor that is a disjoint union of smooth components, the theorem shows that the GW invariants are universal functions determined by the genus of this canonical divisor components and the holomorphic Euler characteristic of the surface. We compute special cases of these universal functions.

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Power-Law Eigenvalue Density, Scaling, And Critical Random-Matrix Ensembles, K. A. Muttalib, Mourand E. H. Ismail Jan 2007

Power-Law Eigenvalue Density, Scaling, And Critical Random-Matrix Ensembles, K. A. Muttalib, Mourand E. H. Ismail

Faculty Bibliography 2000s

We consider a class of rotationally invariant unitary random matrix ensembles where the eigenvalue density falls off as an inverse power law. Under a scaling appropriate for such power-law densities (different from the scaling required in Gaussian random matrix ensembles), we calculate exactly the two-level kernel that determines all eigenvalue correlations. We show that such ensembles belong to the class of critical ensembles.

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Space Velocities Of L- And T-Type Dwarfs, M. R. Zapatero Osorio, E. L. Martin, V. J. S. Béjar, H. Bouy, R. Deshpande, R. J. Wainscoat Jan 2007

Space Velocities Of L- And T-Type Dwarfs, M. R. Zapatero Osorio, E. L. Martin, V. J. S. Béjar, H. Bouy, R. Deshpande, R. J. Wainscoat

Faculty Bibliography 2000s

We have obtained radial velocities of a sample of 18 ultracool dwarfs (M6.5-T8) using high-resolution, near-infrared spectra obtained with NIRSPEC and the Keck II telescope. We have confirmed that the radial velocity of G1 570D is coincident with that of the K-type primary star G1 570A, thus providing additional support for their true companionship. The presence of planetary-mass companions around 2MASS J05591914-1404488 (T4.5 V) has been analyzed using five NIRSPEC radial velocity measurements obtained over a period of 4.37 yr. We have computed UVW space motions for a total of 21 L and T dwarfs within 20 pc of the …

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Polarization-Induced Spectral Changes On Propagation Of Stochastic Electromagnetic Beams, Jixiong Pu, Olga Korotkova, Emil Wolf Jan 2007

Polarization-Induced Spectral Changes On Propagation Of Stochastic Electromagnetic Beams, Jixiong Pu, Olga Korotkova, Emil Wolf

Faculty Bibliography 2000s

It was shown some years ago that the spectrum of a stochastic scalar field depends not only on the source spectrum but also on the degree of coherence of the source. In this paper we show that there are electromagnetic fields for which not only the state of coherence of the source, but also its degree of polarization affect the spectrum of the radiated field. We illustrate the analysis by diagrams which show the far-zone spectra of some stochastic electromagnetic beams generated by sources of different states of coherence and different degrees of polarization. The spectra of the radiated field …

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Analysis Of Beam Wander Effects For A Horizontal-Path Propagating Gaussian-Beam Wave: Focused Beam Case, Jaume Recolons, Larry C. Andrews, Ronald L. Phillips Jan 2007

Analysis Of Beam Wander Effects For A Horizontal-Path Propagating Gaussian-Beam Wave: Focused Beam Case, Jaume Recolons, Larry C. Andrews, Ronald L. Phillips

Faculty Bibliography 2000s

Failure of the first-order Rytov approximation to properly predict the scintillation index of a large-aperture focused beam, or an uplink collimated (or focused) beam, has been discussed in several recent publications, which cite beam wander effects as the main reason for this failure. We use computer simulations to examine several aspects of beam wander phenomena on a propagating convergent beam in the weak-fluctuation regime over a horizontal path at high altitude for which the refractive index structure parameter is on the order of C-n(2)= 1.39 x 10(-16) m(-2/3). Simulation results are presented at various ranges up to 10 km for …

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Wireless Pressure Sensor Using Laser Targeting Of Silicon Carbide, Nabeel A. Riza, Farzan Ghauri, Frank Perez Jan 2007

Wireless Pressure Sensor Using Laser Targeting Of Silicon Carbide, Nabeel A. Riza, Farzan Ghauri, Frank Perez

Faculty Bibliography 2000s

To the best of our knowledge, proposed is the first extreme-environment wireless pressure sensor design using a remoted single-crystal SiC chip within a pressurized capsule. A detailed theoretical analysis of the sensor system is performed, including the SiC chip's mechanical response within the pressure capsule and the pressure measurement technique's optical response based on image demagnification. The remote sensor was experimentally tested at room temperature for pressures up to 41 atm, and the sensor response is consistent with the theoretical analysis. The demonstrated sensor has a current experimental resolution of 1.17 atm with a designed maximum pressure range of 140 …

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Calculation Of Critical Values For Somerville's Fdr Procedures, Paul N. Somerville Jan 2007

Calculation Of Critical Values For Somerville's Fdr Procedures, Paul N. Somerville

Faculty Bibliography 2000s

A Fortran 95 program has been written to calculate critical values for the step-up and step-down FDR procedures developed by Somerville (2004). The program allows for arbitrary selection of number of hypotheses, FDR rate, one- or two-sided hypotheses, common correlation coefficient of the test statistics and degrees of freedom. An MCV (minimum critical value) may be specified, or the program will calculate a specified number of critical values or steps in an FDR procedure. The program can also be used to efficiently ascertain an upper bound to the number of hypotheses which the procedure will reject, given either the values …

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Nonuniform Average Sampling And Reconstruction Of Signals With Finite Rate Of Innovation, Qiyu Sun Jan 2007

Nonuniform Average Sampling And Reconstruction Of Signals With Finite Rate Of Innovation, Qiyu Sun

Faculty Bibliography 2000s

From an average ( ideal) sampling/reconstruction process, the question arises whether the original signal can be recovered from its average (ideal) samples and, if so, how. We consider the above question under the assumption that the original signal comes from a prototypical space modeling signals with a finite rate of innovation, which includes finitely generated shift-invariant spaces, twisted shift-invariant spaces associated with Gabor frames and Wilson bases, and spaces of polynomial splines with nonuniform knots as its special cases. We show that the displayer associated with an average (ideal) sampling/reconstruction process, which has a well-localized average sampler, can be found …

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Free Energy Of Dna Duplex Formation On Short Oligonucleotide Microarrays, Li Zhang, Chunlei Wu, Roberto Carta, Haitao Zhao Jan 2007

Free Energy Of Dna Duplex Formation On Short Oligonucleotide Microarrays, Li Zhang, Chunlei Wu, Roberto Carta, Haitao Zhao

Faculty Bibliography 2000s

DNA/DNA duplex formation is the basic mechanism that is used in genome tiling arrays and SNP arrays manufactured by Affymetrix. However, detailed knowledge of the physical process is still lacking. In this study, we show a free energy analysis of DNA/DNA duplex formation these arrays based on the positional-dependent nearest-neighbor (PDNN) model, which was developed previously for describing DNA/RNA duplex formation on expression microarrays. Our results showed that the two ends of a probe contribute less to the stability of the duplexes and that there is a microarray surface effect on binding affinities. We also showed that free energy cost …

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Gap-Based Estimation: Choosing The Smoothing Parameters For Probabilistic And General Regression Neural Networks, Mingyu Zhong, Dave Coggeshall, Ehsan Ghaneie, Thomas Pope, Mark Rivera, Michael Georgiopoulos, Georgios C. Anagnostopoulos, Mansooreh Mollaghasemi, Samuel Richie Jan 2007

Gap-Based Estimation: Choosing The Smoothing Parameters For Probabilistic And General Regression Neural Networks, Mingyu Zhong, Dave Coggeshall, Ehsan Ghaneie, Thomas Pope, Mark Rivera, Michael Georgiopoulos, Georgios C. Anagnostopoulos, Mansooreh Mollaghasemi, Samuel Richie

Faculty Bibliography 2000s

Probabilistic neural networks (PNN) and general regression neural networks (GRNN) represent knowledge by simple but interpretable models that approximate the optimal classifier or predictor in the sense of expected value of the accuracy. These models require the specification of an important smoothing parameter, which is usually chosen by crossvalidation or clustering. In this letter, we demonstrate the problems with the cross-validation and clustering approaches to specify the smoothing parameter, discuss the relationship between this parameter and some of the data statistics, and attempt to develop a fast approach to determine the optimal value of this parameter. Finally, through experimentation, we …

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Stable Dual-Wavelength Operation Of Ingaas Diode Lasers With Volume Bragg Gratings, S. A. Zolotovskayaa, N. Daghestani, G. B. Venus, L. B. Glebov, V. I. Smirnov, E. U. Rafailov Jan 2007

Stable Dual-Wavelength Operation Of Ingaas Diode Lasers With Volume Bragg Gratings, S. A. Zolotovskayaa, N. Daghestani, G. B. Venus, L. B. Glebov, V. I. Smirnov, E. U. Rafailov

Faculty Bibliography 2000s

Stable dual-wavelength operation of InGaAs diode lasers coupled with volume Bragg gratings has been demonstrated for the continuous wave and gain-switching regimes. Spectral narrowing down to 0.33 nm has been realized with maximum output power of up to 1.85 W from a broad area stripe laser diode in a single-grating external cavity configuration. Spectral separation from 0.5 (0.16 THz) to 6.5 nm (2.05 THz) has been obtained and an output power of up to 1.75 W was achieved in dual-wavelength operation. (C) 2007 American Institute of Physics.

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Recognizing Teamwork Activity In Observations Of Embodied Agents, Linus Jan Luotsinen Jan 2007

Recognizing Teamwork Activity In Observations Of Embodied Agents, Linus Jan Luotsinen

Electronic Theses and Dissertations

This thesis presents contributions to the theory and practice of team activity recognition. A particular focus of our work was to improve our ability to collect and label representative samples, thus making the team activity recognition more efficient. A second focus of our work is improving the robustness of the recognition process in the presence of noisy and distorted data. The main contributions of this thesis are as follows: We developed a software tool, the Teamwork Scenario Editor (TSE), for the acquisition, segmentation and labeling of teamwork data. Using the TSE we acquired a corpus of labeled team actions both …

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Micro-Optic-Spectral-Spatial-Elements (Mosse), Alok Ajay Mehta Jan 2007

Micro-Optic-Spectral-Spatial-Elements (Mosse), Alok Ajay Mehta

Electronic Theses and Dissertations

Over a wide range of applications, optical systems have utilized conventional optics in order to provide the ability to engineer the properties of incident infra-red fields in terms of the transmitted field spectral, spatial, amplitude, phase, and polarization characteristics. These micro/nano-optical elements that provide specific optical functionality can be categorized into subcategories of refractive, diffractive, multi-layer thin film dichroics, 3-D photonic crystals, and polarization gratings. The feasibility of fabrication, functionality, and level of integration which these elements can be used in an optical system differentiate which elements are more compatible with certain systems than others. With enabling technologies emerging allowing …

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Stress, Fatigue And Workload: Determining The Combined Affect On Human Performance, Jessica Mock-Mclaughlin Jan 2007

Stress, Fatigue And Workload: Determining The Combined Affect On Human Performance, Jessica Mock-Mclaughlin

Electronic Theses and Dissertations

This research generated a model that will help to predict, prevent, control and mitigate the occurrence of task related factors that negatively influence stress, fatigue, and workload; thus enhancing human performance. Past research efforts involving stress, fatigue and workload identified factors that influence a change in performance (Lan, Ji and Looney, 2003, and Hancock & Warm, 1989). Also, while some mathematical models have been developed within each respective area, however, there is no evidence of an integrated model describing the combined affect of stress, fatigue and workload. To respond to this research gap, a quantitative model representing the state of …

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Examining Sociomathematical Norms Within The Context Of Decimals And Fractions In A Sixth Grade Classroom, Marino Nardelli Jan 2007

Examining Sociomathematical Norms Within The Context Of Decimals And Fractions In A Sixth Grade Classroom, Marino Nardelli

Electronic Theses and Dissertations

Social norms are patterns of behavior expected within a particular society in a given situation. Social norms can be shared belief of what is normal and acceptable shapes and enforces the actions of people in a society. In the educational classroom, they are characteristics that constitute the classroom participation structure. Sociomathematical norms are fine-grained aspects of general social norms specifically related to mathematical practices. These can include, but are not limited to, a student-centered classroom that includes the expectation that the students should present their solution methods by describing actions on mathematical objects rather than simply accounting for calculational manipulations. …

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A Novel Setup For High-Pressure Raman Spectroscopy Under A Microscope, Thomas Andrew Oakeson Jan 2007

A Novel Setup For High-Pressure Raman Spectroscopy Under A Microscope, Thomas Andrew Oakeson

Electronic Theses and Dissertations

Functional properties of biological molecules and cells are affected by environmental parameters such as temperature and pressure. While Raman spectroscopy provides an intrinsic probe of molecular structural changes, the incorporation of a microscope enables studies of minuscule amounts of biological compounds with spatial resolution on a micron scale. We have developed a novel setup which combines a Raman microscope and a high pressure cell. A micro-capillary made out of fused silica simultaneously serves as the supporting body and the optical window of the pressure cell. The cell has been tested over the pressure range from 0.1 to 4 kbar. Raman …

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