14,008 research outputs found

    Teachers guide for building and operating weather satellite ground stations for high school science

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    A number of colleges and universities are operating APT direct readout stations. However, high school science teachers have often failed to realize the potential of meteorological satellites and their products as unique instructional tools. The ability to receive daily pictures from these satellites offers exciting opportunities for secondary school teachers and students to assemble the electronic hardware and to view real time pictures of Earth from outer space. The station and pictures can be used in the classroom to develop an approach to science teaching that could span many scientific disciplines and offer many opportunities for student research and participation in scientific processes. This can be accomplished with relatively small expenditures of funds for equipment. In most schools some of the equipment may already be available. Others can be constructed by teachers and/or students. Yet another source might be the purchase of used equipment from industry or through the government surplus channels. The information necessary for individuals unfamiliar with these systems to construct a direct readout for receiving real time APT photographs on a daily basis in the classroom is presented

    The force, power and energy of the 100 meter sprint

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    At the 2008 Summer Olympics in Beijing, Usain Bolt broke the world record for the 100 m sprint. Just one year later, at the 2009 World Championships in Athletics in Berlin he broke it again. A few months after Beijing, Eriksen et al. studied Bolt's performance and predicted that Bolt could have run about one-tenth of a second faster, which was confirmed in Berlin. In this paper we extend the analysis of Eriksen et al. to model Bolt's velocity time-dependence for the Beijing 2008 and Berlin 2009 records. We deduce the maximum force, the maximum power, and the total mechanical energy produced by Bolt in both races. Surprisingly, we conclude that all of these values were smaller in 2009 than in 2008

    NOTAS DE MEDICINA PRÁCTICA: Oftalmología. Infecciones Oculares

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    Recent Developments

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    In a free speech and free exercise case involving the Business Leaders in Christ at the University of Iowa, the Eighth Circuit Court of Appeals reversed the Southern District of Iowa by holding that University officials should not be granted qualified immunity based on the student organization’s free speech claim

    A 233 km Tunnel for Lepton and Hadron Colliders

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    A decade ago, a cost analysis was conducted to bore a 233 km circumference Very Large Hadron Collider (VLHC) tunnel passing through Fermilab. Here we outline implementations of e+e−e^+e^-, ppˉp \bar{p}, and ÎŒ+Ό−\mu^+ \mu^- collider rings in this tunnel using recent technological innovations. The 240 and 500 GeV e+e−e^+e^- colliders employ Crab Waist Crossings, ultra low emittance damped bunches, short vertical IP focal lengths, superconducting RF, and low coercivity, grain oriented silicon steel/concrete dipoles. Some details are also provided for a high luminosity 240 GeV e+e−e^+ e^- collider and 1.75 TeV muon accelerator in a Fermilab site filler tunnel. The 40 TeV ppˉp \bar{p} collider uses the high intensity Fermilab pˉ\bar{p} source, exploits high cross sections for ppˉp \bar{p} production of high mass states, and uses 2 Tesla ultra low carbon steel/YBCO superconducting magnets run with liquid neon. The 35 TeV muon ring ramps the 2 Tesla superconducting magnets at 9 Hz every 0.4 seconds, uses 250 GV of superconducting RF to accelerate muons from 1.75 to 17.5 TeV in 63 orbits with 71% survival, and mitigates neutrino radiation with phase shifting, roller coaster motion in a FODO lattice.Comment: LaTex, 6 pages, 1 figure, Advanced Accelerator Concepts Workshop, Austin, TX, 10-15 June 201

    Recent Developments

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    In a free speech and free exercise case involving the Business Leaders in Christ at the University of Iowa, the Eighth Circuit Court of Appeals reversed the Southern District of Iowa by holding that University officials should not be granted qualified immunity based on the student organization’s free speech claim
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