8,795 research outputs found

    Herding Cats: Improving Law School Teaching

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    What makes a good law teacher? Is excellence in teaching largely a matter of intellectual brilliance, of superior organization and delivery of material, of friendliness and fairness to one\u27s students? Or does it have more to do with style, with stage presence, with the ability to engage an audience in the act of reflective and spontaneous thinking? While the question of how to define and evaluate teaching necessarily bedevils deans and tenure committees who must make personnel decisions, the focus on defining the competent teacher has obscured from faculty attention the more fundamental question: how can we implement a system to improve faculty performance across the board? It is this question that law schools around the country have not adequately addressed. Three years ago, the faculty of Franklin Pierce Law Center adopted a program to improve our classroom teaching. This article describes and evaluates that program, in which all three authors played a role

    Analysis of the CLEAN algorithm and implications for superresolution

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    J. Opt. Soc. Am. A, Volume 12, No. 5, 853-860, (May 1995)The capability of the CLEAN algorithm, which is able to develop image information corresponding to spatial frequencies for which the imaging systems optical transfer function (OTF) is equal to zero, is shown to be dependent on the limited size of the object being imaged. It is found that this capability is available without a severe signal-to-noise-ratio penalty only for the recovery of a spatial frequency that is sufficiently close to some other spatial frequency for which the OTF is not equal to zero. As used here the term sufficiently close means that the magnitude of the separation of the spatial frequencies is less than one half of the inverse of the size of the object being imaged. This represents a limitation of CLEANƃ ƃ ƃ ƃ ƂĀ¢ s capability deriving from object size. It is suggested that this capability can be thought of in terms of superresolution, with the same limitation in regard to object size

    Determination of complex dielectric functions of ion implanted and implantedā€annealed amorphous silicon by spectroscopic ellipsometry

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    Measuring with a spectroscopic ellipsometer (SE) in the 1.8ā€“4.5 eV photon energy region we determined the complex dielectric function (Ļµ = Ļµ1 + iĻµ2) of different kinds of amorphous silicon prepared by selfā€implantation and thermal relaxation (500ā€‰Ā°C, 3 h). These measurements show that the complex dielectric function (and thus the complex refractive index) of implanted aā€Si (iā€aā€Si) differs from that of relaxed (annealed) aā€Si (rā€aā€Si). Moreover, its Ļµ differs from the Ļµ of evaporated aā€Si (eā€aā€Si) found in the handbooks as Ļµ for aā€Si. If we use this Ļµ to evaluate SE measurements of ion implanted silicon then the fit is very poor. We deduced the optical band gap of these materials using the Davisā€“Mott plot based on the relation: (Ļµ2E2)1/3 āˆ¼ (Eāˆ’ Eg). The results are: 0.85 eV (iā€aā€Si), 1.12 eV (eā€aā€Si), 1.30 eV (rā€aā€Si). We attribute the optical change to annihilation of point defects

    Optical propagation measurements at Emerson Lake, 1968

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    Optical propagation measurements in inhomogeneous atmosphere at Emerson Lake, California for optical propagation theory validity testin

    A Side of Mercury Not Seen By Mariner 10

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    More than 60,000 images of Mercury were taken at ~29 deg elevation during two sunrises, at 820 nm, and through a 1.35 m diameter off-axis aperture on the SOAR telescope. The sharpest resolve 0.2" (140 km) and cover 190-300 deg longitude -- a swath unseen by the Mariner 10 spacecraft -- at complementary phase angles to previous ground-based optical imagery. Our view is comparable to that of the Moon through weak binoculars. Evident are the large crater Mozart shadowed on the terminator, fresh rayed craters, and other albedo features keyed to topography and radar reflectivity, including the putative huge ``Basin S'' on the limb. Classical bright feature Liguria resolves across the northwest boundary of the Caloris basin into a bright splotch centered on a sharp, 20 km diameter radar crater, and is the brightest feature within a prominent darker ``cap'' (Hermean feature Solitudo Phoenicis) that covers the northern hemisphere between longitudes 140-250 deg. The cap may result from space weathering that darkens via a magnetically enhanced flux of the solar wind, or that reddens low latitudes via high solar insolation.Comment: 7 pages, 4 PDF figures, pdfLaTeX, typos corrected, Fig. 2 modified slightly to add crater diameters not given in published versio

    An Analysis of Fundamental Waffle Mode in Early AEOS Adaptive Optics Images

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    Adaptive optics (AO) systems have significantly improved astronomical imaging capabilities over the last decade, and are revolutionizing the kinds of science possible with 4-5m class ground-based telescopes. A thorough understanding of AO system performance at the telescope can enable new frontiers of science as observations push AO systems to their performance limits. We look at recent advances with wave front reconstruction (WFR) on the Advanced Electro-Optical System (AEOS) 3.6 m telescope to show how progress made in improving WFR can be measured directly in improved science images. We describe how a "waffle mode" wave front error (which is not sensed by a Fried geometry Shack-Hartmann wave front sensor) affects the AO point-spread function (PSF). We model details of AEOS AO to simulate a PSF which matches the actual AO PSF in the I-band, and show that while the older observed AEOS PSF contained several times more waffle error than expected, improved WFR techniques noticeably improve AEOS AO performance. We estimate the impact of these improved WFRs on H-band imaging at AEOS, chosen based on the optimization of the Lyot Project near-infrared coronagraph at this bandpass.Comment: 15 pages, 11 figures, 1 table; to appear in PASP, August 200

    Two-body effects in the decay rate of atomic levels

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    Recoil corrections to the atomic decay rate are considered in the order of Zm/M . The expressions are treated exactly without any expansion over Z alpha. The expressions obtained are valid both for muonic atoms (for which they contribute on the level of a few percent in high Z ions) and for electronic atoms. Explicit results for Lyman-alpha transitions for low-Z of the order (Zm/M)(Z alpha)^2 are also presented.Comment: 5 pages, 1 table, email: [email protected]

    Teacher emotion research: Introducing a conceptual model to guide future research

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    This article reports on the development of a conceptual model of teacher emotion through a review of teacher emotion research published between 2003 and 2013. By examining 82 publications regarding teacher emotion, the main aim of the review was to identify how teacher emotion was conceptualised in the literature and develop a conceptual model to illustrate the findings. Interestingly, few papers explicitly defined ā€˜emotionā€™ or ā€˜teacher emotionā€™ but described the functions of emotion (such as providing information) and influences on emotion (such as personal characteristics), so these were also used to build the conceptual model. The literature also highlighted the complexities of emotion, with implications for how teacher emotion should be studied. The model proposed aims to clarify how emotion research has been conceptualised within education research contexts

    Stellar Dynamics and the implications on the merger evolution in NGC6240

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    We report near-infrared integral field spectroscopy of the luminous merging galaxy NGC 6240. Stellar velocities show that the two K-band peaks separated by 1.6arcsec are the central parts of inclined, rotating disk galaxies with equal mass bulges. The dynamical masses of the nuclei are much larger than the stellar mass derived from the K-band light, implying that the progenitor galaxies were galaxies with massive bulges. The K-band light is dominated by red supergiants formed in the two nuclei in starbursts, triggered ~2x10^7 years ago, possibly by the most recent perigalactic approach. Strong feedback effects of a superwind and supernovae are responsible for a short duration burst (~5x10^6 years) which is already decaying. The two galaxies form a prograde-retrograde rotating system and from the stellar velocity field it seems that one of the two interacting galaxies is subject to a prograde encounter. Between the stellar nuclei is a prominent peak of molecular gas (H_2, CO). The stellar velocity dispersion peaks there indicating that the gas has formed a local, self-gravitating concentration decoupled from the stellar gravitational potential. NGC 6240 has previously been reported to fit the paradigm of an elliptical galaxy formed through the merger of two galaxies. This was based on the near-infrared light distribution which follows a r^1/4-law. Our data cast strong doubt on this conclusion: the system is by far not relaxed, rotation plays an important role, as does self-gravitating gas, and the near-infrared light is dominated by young stars.Comment: 34 pages, 11 figures, using AASTEX 5.0rc3.1, paper submitted to the Astrophysical Journal, revised versio
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