36,309 research outputs found

    Integration of Technology in Math and Science Education – A Model for Teaching Elementary and Middle School Pre-Service Teachers

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    This paper describes the development and implementation of a course, Integration of Technology in Math and Science Education, to introduce elementary and middle school pre-service teachers to real technology skills that they can use in their future classrooms. Activities allowed the students to learn technology skills while using the Internet to enrich their content skills and share information with their fellow students. The course was designed to allow students to master a variety of technology skills, and see how these skills can be used appropriately in their future classrooms, while also increasing their comfort level to use the technology and reduce their resistance and anxiety to use it later in their real-time classrooms. During the class hands-on activities, the students became ïŹ‚uent at using the Internet for enrichment and communication, and at developing strategies for using their new skills to present SOL-relevant lesson plans. Students enter this course with very little in the way of educational technology skills, but leave with a teaching toolbox ïŹlled with new skills

    Fluctuating loops and glassy dynamics of a pinned line in two dimensions

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    We represent the slow, glassy equilibrium dynamics of a line in a two-dimensional random potential landscape as driven by an array of asymptotically independent two-state systems, or loops, fluctuating on all length scales. The assumption of independence enables a fairly complete analytic description. We obtain good agreement with Monte Carlo simulations when the free energy barriers separating the two sides of a loop of size L are drawn from a distribution whose width and mean scale as L^(1/3), in agreement with recent results for scaling of such barriers.Comment: 11 pages, 4 Postscript figure

    Transport in Graphene Tunnel Junctions

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    We present a technique to fabricate tunnel junctions between graphene and Al and Cu, with a Si back gate, as well as a simple theory of tunneling between a metal and graphene. We map the differential conductance of our junctions versus probe and back gate voltage, and observe fluctuations in the conductance that are directly related to the graphene density of states. The conventional strong-suppression of the conductance at the graphene Dirac point can not be clearly demonstrated, but a more robust signature of the Dirac point is found: the inflection in the conductance map caused by the electrostatic gating of graphene by the tunnel probe. We present numerical simulations of our conductance maps, confirming the measurement results. In addition, Al causes strong n-doping of graphene, Cu causes a moderate p-doping, and in high resistance junctions, phonon resonances are observed, as in STM studies.Comment: 22 pages, 5 figure

    Summary of results of NASA F-15 flight research program

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    NASA conducted a multidisciplinary flight research program on the F-15 airplane. The program began in 1976 when two preproduction airplanes were obtained from the U.S. Air Force. Major projects involved stability and control, handling qualities, propulsion, aerodynamics, propulsion controls, and integrated propulsion-flight controls. Several government agencies and aerospace contractors were involved. In excess of 330 flights were flown, and over 85 papers and reports were published. This document describes the overall program, the projects, and the key results. The F-15 was demonstrated to be an excellent flight research vehicle, producing high-quality results

    Longitudinal Current Dissipation in Bose-glass Superconductors

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    A scaling theory of vortex motion in Bose glass superconductors with currents parallel to the common direction of the magnetic field and columnar defects is presented. Above the Bose-glass transition the longitudinal DC resistivity ÏâˆŁâˆŁ(T)∌(T−TBG)Îœâ€Čzâ€Č\rho_{||}(T)\sim (T-T_{BG})^{\nu' z'} vanishes much faster than the corresponding transverse resistivity ρ⊄(T)∌(T−TBG)Îœâ€Č(zâ€Č−2)\rho_{\perp}(T)\sim (T-T_{BG})^{\nu' (z'-2)}, thus {\it reversing} the usual anisotropy of electrical transport in the normal state of layered superconductors. In the presence of a current J\bf J at an angle ΞJ\theta_J with the common field and columnar defect axis, the electric field angle ΞE\theta_E approaches π/2\pi/2 as T→TBG+T\rightarrow T_{BG}^+. Scaling also predicts the behavior of penetration depths for the AC currents as T→TBG−T\rightarrow T_{BG}^-, and implies a {\it jump discontinuity} at TBGT_{BG} in the superfluid density describing transport parallel to the columns.Comment: 5 pages, revte

    Economic performance or electoral necessity? Evaluating the system of voluntary income to political parties

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    Whilst the public funding of political parties is the norm in western democracies, its comprehensive introduction has been resisted in Britain. Political and electoral arrangements in Britain require parties to function and campaign on a regular basis, whilst their income follows cycles largely related to general elections. This article shows that the best predictor of party income is the necessity of a well-funded general election campaign rather than party performance. As a result, income can only be controlled by parties to a limited degree, which jeopardises their ability to determine their own financial position and fulfil their functions as political parties

    Distributions of gaps and end-to-end correlations in random transverse-field Ising spin chains

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    A previously introduced real space renormalization-group treatment of the random transverse-field Ising spin chain is extended to provide detailed information on the distribution of the energy gap and the end-to-end correlation function for long chains with free boundary conditions. Numerical data, using the mapping of the problem to free fermions, are found to be in good agreement with the analytic finite size scaling predictions.Comment: 12 pages revtex, 10 figures, submitted to Phys. Rev.

    Design and Testing of an Ecological Invert Culvert

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    Consideration of stream ecology and stream biology is an emerging trend in the effective design of culverts. Current methods of burying the inverts of culvert have been shown to provide limited or no benefits. To address limitations in existing technologies and current design practices, Colorado State University has developed a culvert invert technology that retains streambed material and provides stream ecology benefits. In this session we will review the development and testing process from Colorado State University

    Systematic review of the current status of cadaveric simulation for surgical training

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    Background: There is growing interest in and provision of cadaveric simulation courses for surgical trainees. This is being driven by the need to modernize and improve the efficiency of surgical training within the current challenging training climate. The objective of this systematic review is to describe and evaluate the evidence for cadaveric simulation in postgraduate surgical training. Methods: A PRISMA‐compliant systematic literature review of studies that prospectively evaluated a cadaveric simulation training intervention for surgical trainees was undertaken. All relevant databases and trial registries were searched to January 2019. Methodological rigour was assessed using the widely validated Medical Education Research Quality Index (MERSQI) tool. Results: A total of 51 studies were included, involving 2002 surgical trainees across 69 cadaveric training interventions. Of these, 22 assessed the impact of the cadaveric training intervention using only subjective measures, five measured impact by change in learner knowledge, and 23 used objective tools to assess change in learner behaviour after training. Only one study assessed patient outcome and demonstrated transfer of skill from the simulated environment to the workplace. Of the included studies, 67 per cent had weak methodology (MERSQI score less than 10·7). Conclusion: There is an abundance of relatively low‐quality evidence showing that cadaveric simulation induces short‐term skill acquisition as measured by objective means. There is currently a lack of evidence of skill retention, and of transfer of skills following training into the live operating theatre
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