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Elementary Math Achievement in Texas: What is Working?

Description: Elementary math teachers (76) from selected Texas schools that included Grade 5 responded to an online self-report survey with respect to school-level factors that may be associated with student math achievement. Questions on the survey focused on school-level factors related to math, campus leadership, integration of technology in the math classroom, teacher expectations, utilization of student data in decision-making and professional development. The schools included in the study were rated as Acceptable or Exemplary schools by the Texas Education Agency for three-consecutive years (2007-2010). Logistic regression techniques were used to analyze the data and 11 questions out of 45 were analyzed to determine the odds ratio. Factors that were correlated with being an Exemplary campus were teacher certification routes, not benchmarking student progress, implementation of response to intervention (RTI), classroom management focus (equally divided between student and teacher centered) within the classroom, and technology integration. The results indicated that at the .05 level of probability, the only factor that met that level of significance was full implementation of RTI.
Date: May 2011
Creator: Moore, Linda H.
Partner: UNT Libraries

First-Year Teacher Usage of Manipulatives in Mathematics Instruction: A Case Study

Description: This qualitative case study examined the use of manipulatives in mathematics instruction by six first-year intermediate teachers in a north Texas school district. Their preparation for, access to, and perceptions about manipulatives were examined. Specific content associated with manipulative usage was identified.
Date: December 1989
Creator: Sylvester, Barbara N. (Barbara Nelson)
Partner: UNT Libraries

Computational Science Research in Support of Petascale Electromagnetic Modeling

Description: Computational science research components were vital parts of the SciDAC-1 accelerator project and are continuing to play a critical role in newly-funded SciDAC-2 accelerator project, the Community Petascale Project for Accelerator Science and Simulation (ComPASS). Recent advances and achievements in the area of computational science research in support of petascale electromagnetic modeling for accelerator design analysis are presented, which include shape determination of superconducting RF cavities, mesh-based multilevel preconditioner in solving highly-indefinite linear systems, moving window using h- or p- refinement for time-domain short-range wakefield calculations, and improved scalable application I/O.
Date: June 20, 2008
Creator: Lee, L.-Q.; Akcelik, V; Ge, L; Chen, S; Schussman, G; Candel, A et al.
Partner: UNT Libraries Government Documents Department

Superpotentials for Quiver Gauge Theories

Description: We compute superpotentials for quiver gauge theories arising from marginal D-Brane decay on collapsed del Pezzo cycles S in a Calabi-Yau X. This is done using the machinery of A{sub {infinity}} products in the derived category of coherent sheaves of X, which in turn is related to the derived category of S and quiver path algebras. We confirm that the superpotential is what one might have guessed from analyzing the moduli space, i.e., it is linear in the fields corresponding to the Exts of the quiver and that each such Ext multiplies a polynomial in Exts equal to precisely the relation represented by the Ext.
Date: June 10, 2005
Creator: Aspinwall, Paul S.; /Stanford U., Phys. Dept. /SLAC /Duke U., CGTP; Fidkowski, Lukasz M. & /Stanford U., Phys. Dept.
Partner: UNT Libraries Government Documents Department

Omega3P: A Parallel Finite-Element Eigenmode Analysis Code for Accelerator Cavities

Description: Omega3P is a parallel eigenmode calculation code for accelerator cavities in frequency domain analysis using finite-element methods. In this report, we will present detailed finite-element formulations and resulting eigenvalue problems for lossless cavities, cavities with lossy materials, cavities with imperfectly conducting surfaces, and cavities with waveguide coupling. We will discuss the parallel algorithms for solving those eigenvalue problems and demonstrate modeling of accelerator cavities through different examples.
Date: March 4, 2009
Creator: Lee, Lie-Quan; Li, Zenghai; Ng, Cho; Ko, Kwok & /SLAC
Partner: UNT Libraries Government Documents Department

A Moving Window Technique in Parallel Finite Element Time Domain Electromagnetic Simulation

Description: A moving window technique for the finite element time domain (FETD) method is developed to simulate the propagation of electromagnetic waves induced by the transit of a charged particle beam inside large and long structures. The window moving along with the beam in the computational domain adopts high-order finite-element basis functions through p refinement and/or a high-resolution mesh through h refinement so that a sufficient accuracy is attained with substantially reduced computational costs. Algorithms to transfer discretized fields from one mesh to another, which are the key to implementing a moving window in a finite-element unstructured mesh, are presented. Numerical experiments are carried out using the moving window technique to compute short-range wakefields in long accelerator structures. The results are compared with those obtained from the normal FETD method and the advantages of using the moving window technique are discussed.
Date: June 7, 2010
Creator: Lee, Lie-Quan; Candel, Arno; Ng, Cho; Ko, Kwok; /SLAC & ,
Partner: UNT Libraries Government Documents Department

Cross-Sectional Studies of the Impacts of Background Sounds on Math and Language Performance

Description: Presented at the 2017 International Conference on Knowledge Management. This presentation reports a series of seven studies examining the extent to which background sounds impact individuals' math and language task performance.
Date: October 26, 2017
Creator: Cockerham, Debbie; Lin, Lin; Chang, Zhengsi & Schellen, Mike
Partner: UNT Libraries

Dynamic Quantum Clustering: A Tool for Unsupervised Exploration of Structures in Data

Description: A given set of data-points in some feature space may be associated with a Schroedinger equation whose potential is determined by the data. This is known to lead to good clustering solutions. Here we extend this approach into a full-fledged dynamical scheme using a time-dependent Schroedinger equation with a small diffusion component. Moreover, we approximate this Hamiltonian formalism by a truncated calculation within a set of Gaussian wave functions (coherent states) centered around the original points. This allows for analytic evaluation of the time evolution of all such states, opening up the possibility of exploration of relationships among data-points through observation of varying dynamical-distances among points and convergence of points into clusters. This formalism may be further supplemented by preprocessing, such as dimensional reduction through singular value decomposition or feature filtering.
Date: October 30, 2008
Creator: Weinstein, Marvin; /SLAC; Horn, David & U., /Tel Aviv
Partner: UNT Libraries Government Documents Department

On Projecting Discretized Electromagnetic Fields with Unstructured Grids

Description: A new method for projecting discretized electromagnetic fields on one unstructured grid to another grid is presented in this paper. Two examples are used for studying the errors of different projection methods. The analysis shows that the new method is very effective on balancing both the error of the electric field and that of the magnetic field (or curl of the electric field).
Date: August 13, 2008
Creator: Lee, Lie-Quan; Candel, Arno; Kabel, Andrea; Li, Zenghai & /SLAC
Partner: UNT Libraries Government Documents Department

Shape Determination for Deformed Electromagnetic Cavities

Description: The measured physical parameters of a superconducting cavity differ from those of the designed ideal cavity. This is due to shape deviations caused by both loose machine tolerances during fabrication and by the tuning process for the accelerating mode. We present a shape determination algorithm to solve for the unknown deviations from the ideal cavity using experimentally measured cavity data. The objective is to match the results of the deformed cavity model to experimental data through least-squares minimization. The inversion variables are unknown shape deformation parameters that describe perturbations of the ideal cavity. The constraint is the Maxwell eigenvalue problem. We solve the nonlinear optimization problem using a line-search based reduced space Gauss-Newton method where we compute shape sensitivities with a discrete adjoint approach. We present two shape determination examples, one from synthetic and the other from experimental data. The results demonstrate that the proposed algorithm is very effective in determining the deformed cavity shape.
Date: December 10, 2007
Creator: Akcelik, Volkan; Ko, Kwok; Lee, Lie-Quan; Li, Zhenghai; Ng, Cho-Kuen; Xiao, Liling et al.
Partner: UNT Libraries Government Documents Department

Strange Bedfellows: Quantum Mechanics and Data Mining

Description: Last year, in 2008, I gave a talk titled Quantum Calisthenics. This year I am going to tell you about how the work I described then has spun off into a most unlikely direction. What I am going to talk about is how one maps the problem of finding clusters in a given data set into a problem in quantum mechanics. I will then use the tricks I described to let quantum evolution lets the clusters come together on their own.
Date: December 16, 2009
Creator: Weinstein, Marvin
Partner: UNT Libraries Government Documents Department

Scanning SQUID microscopy on polycrystalline SmFeAsO_{0.85} and NdFeAsO_{0.94}F_{0.06}

Description: The order parameter of the recently-discovered ferric arsenide family of superconductors remains uncertain. Some early experiments on polycrystalline samples suggested line nodes in the order parameter, however later experiments on single crystals have strongly supported fully-gapped superconductivity. An absence of nodes does not rule out unconventional order: {pi} phase shifts between the separate Fermi sheets and time-reversal symmetry-breaking components in the order parameter remain possibilities. One test for unconventional order is scanning magnetic microscopy on well-coupled polycrystalline samples: d- or p-wave order would result in orbital frustration, leading to spontaneous currents and magnetization in the superconducting state. We have performed scanning SQUID microscopy on SmFeAsO{sub 0.85} and NdFeAsO{sub 0.94}F{sub 0.06}, and in neither material do we find spontaneous orbital currents, ruling out p- or d-wave order.
Date: January 8, 2009
Creator: Hicks, Clifford W.; Lippman, Thomas M.; Moler, Kathryn A.; Huber, Martin E.; Ren, Zhi-An & Zhao, Zhong-Xian
Partner: UNT Libraries Government Documents Department

Limits on the Superconducting Order Parameter in NdFeAsO_{1-x}F_y from Scanning SQUID Microscopy

Description: Identifying the symmetry of the superconducting order parameter in the recently-discovered ferrooxypnictide family of superconductors, RFeAsO{sub 1-x}F{sub y}, where R is a rare earth, is a high priority. Many of the proposed order parameters have internal {pi} phase shifts, like the d-wave order found in the cuprates, which would result in direction-dependent phase shifts in tunneling. In dense polycrystalline samples, these phase shifts in turn would result in spontaneous orbital currents and magnetization in the superconducting state. We perform scanning SQUID microscopy on a dense polycrystalline sample of NdFeAsO{sub 0.94}F{sub 0.06} with T{sub c} = 48K and find no such spontaneous currents, ruling out many of the proposed order parameters.
Date: January 8, 2009
Creator: Hicks, Clifford W.; Lippman, Thomas M.; Huber, Martin E.; Ren, Zhi-An; Yang, Jie; Zhao, Zhong-Xian et al.
Partner: UNT Libraries Government Documents Department