Harnessing Technology: new modes of technology-enhanced learning: action research, March 2009

5 action research studie

Mr. Stewart and Mr. Colbert Go to Washington: Television Satirists Outside the Box

The political satirists Jon Stewart and Stephen Colbert are largely celebrated for their nightly television programs, which use humor to offer useful political information, provide important forums for deliberation and debate, and serve as sites for alternative interpretations of political reality. Yet, when the two satirists more directly intervene in the field of politics—which they increasingly do—they are often met by a chorus of criticism that suggests they have improperly crossed normative boundaries. This article explores Stewart and Colbert’s “out of the box” political performances, which include, among others, the 2010 Rally to Restore Sanity, Colbert’s testimony before Congress in the same year, and his on-going efforts to run an actual Super PAC that raises and spends money to influence (and critique) the political process. Examining these and other examples of non-traditional, and clearly border-crossing political satire, we consider the ways in which such multi-modal performances--in and off the television screen--work together to provide information, critique, and commentary, as well as a significant form of moral voice and ethical imperative. In turn, we examine the responses from the political and journalistic establishment, which more often than not, constitutes a form of boundary maintenance that seeks to delegitimize such alternative modes of political engagement. Finally, we discuss the significance of the developing relationship between television entertainment and political performance for our understanding of contemporary political practice

A Planned Jefferson Lab Experiment on Spin-Flavor Decomposition

Experiment E04-113 at Jefferson Lab Hall C plans to measure the beam-target double-spin asymmetries in semi-inclusive deep-inelastic $\vec p(e, e^\prime h)X$ and $\vec d(e, e^\prime h)X$ reactions ($h=\pi^+, \pi^-, K^+$ or$K^-$) with a 6 GeV polarized electron beam and longitudinally polarized NH$_3$ and LiD targets. The high statistic data will allow a spin-flavor decomposition in the region of $x=0.12 \sim 0.41$ at $Q^2=1.21\sim 3.14$ GeV$^2$. Especially, leading-order and next-to-leading order spin-flavor decomposition of $\Delta u_v$, $\Delta d_v$ and $\Delta \bar{u} - \Delta \bar{d}$ will be extracted based on the measurement of the combined asymmetries $A_{1N}^{\pi^+ - \pi^-}$. The possible flavor asymmetry of the polarized sea will be addressed in this experiment.Comment: 4 pages, 2 figures, contribution paper to SPIN2004 conferenc

Simulations of Coaxial Wire Measurements of the Impedance of Asymmetric Structures

Coaxial wire measurements have provided a simple and effective way to measure the beam coupling impedance of accelerator structures for a number of years. It has been known how to measure the longitudinal and dipolar transverse impedance using one and two wires for some time. Recently the ability to measure the quadrupolar impedance of structures exhibiting top/bottom and left/right symmetry has been demonstrated. A method for measuring the beam coupling impedance of asymmetric structures using displaced single wires and two wire measurements is proposed. Simulations of the measurement system are presented with further work proposed

Comparison of the current LHC Collimators and the SLAC Phase 2 Collimator Impedances

One of the key sources of transverse impedance in the LHC has been the secondary graphite collimators that sit close to the beam at all energies. This limits the stable bunch intensity due to transverse coupled-bunch instabilities and transverse mode coupling instability. To counteract this, new secondary collimators have been proposed for the phase II upgrade of the LHC collimation system. A number of designs based on different jaw materials and mechanical designs have been proposed. A comparison of the beam coupling impedance of these different designs derived from simulations are presented, with reference to the existing phase I secondary collimator design

Benchmark ultra-cool dwarfs in widely separated binary systems

Ultra-cool dwarfs as wide companions to subgiants, giants, white dwarfs and main sequence stars can be very good benchmark objects, for which we can infer physical properties with minimal reference to theoretical models, through association with the primary stars. We have searched for benchmark ultra-cool dwarfs in widely separated binary systems using SDSS, UKIDSS, and 2MASS. We then estimate spectral types using SDSS spectroscopy and multi-band colors, place constraints on distance, and perform proper motions calculations for all candidates which have sufficient epoch baseline coverage. Analysis of the proper motion and distance constraints show that eight of our ultra-cool dwarfs are members of widely separated binary systems. Another L3.5 dwarf, SDSS 0832, is shown to be a companion to the bright K3 giant Eta Cancri. Such primaries can provide age and metallicity constraints for any companion objects, yielding excellent benchmark objects. This is the first wide ultra-cool dwarf + giant binary system identified.Comment: 4 pages, 3 figures, conference, "New Technologies for Probing the Diversity of Brown Dwarfs and Exoplanets", oral tal

Evaluation of the Beam Coupling Impedance of New Beam Screen Designs for the LHC Injection Kicker Magnets

During the 2011 run of the LHC there was a significant measured temperature increase in the LHC Injection Kicker Magnets (MKI) during operation with 50ns bunch spacing. This was due to increased beam-induced heating of the magnet due to beam impedance. Due to concerns about future heating with the increased total intensity to nominal and ultimate luminosities a review of the impedance reduction techniques within the magnet was required. A number of new beam screen designs are proposed and their impedance evaluated. Heating estimates are also given with a particular attention paid to future intensity upgrades to ultimate parameters

Film thickness measurements on five fluid formulations by the mercury squeeze film capacitance technique

The thinning characteristics of five fluids were studied by measuring film thickness as a function of time. The mercury squeeze film capacitance technique was used. All tests were performed at room temperature. The synthetic hydrocarbon plus a nematic liquid crystal, N-(p-methoxybenzylidene)-p-butylaniline, thinned according to a Newtonian model and retained its bulk viscosity. The synthetic hydrocarbon plus a phosphonate antiwear additive and the synthetic hydrocarbon plus n-hexadecanol produced residual thick films. The synthetic hydrocarbon base fluids and the synthetic hydrocarbon plus a paraffinic resin displayed viscosity increases during thinning, but no residual films were formed

Coaxial Wire Measurements of Ferrite Kicker Magnets

Fast kicker magnets are used to inject beam into and eject beam out of the CERN accelerator rings. These kickers are generally transmission line type magnets with a rectangular shaped aperture through which the beam passes. Unless special precautions are taken the impedance of the yoke can provoke significant beam induced heating, especially for high intensities. In addition the impedance may contribute to beam instabilities. The results of longitudinal and transverse impedance measurements, for various kicker magnets, are presented and compared with analytical calculations: in addition predictions from a numerical analysis are discussed