113 research outputs found

    Ultra-fast calorimetry study of Ge<sub>2</sub>Sb<sub>2</sub>Te<sub>5</sub> crystallization between dielectric layers

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    Phase changes in chalcogenides such as Ge2Sb2Te5 can be exploited in non-volatile random-access memory, with fast crystallization crucial for device operation. Ultra-fast differential scanning calorimetry, heating at rates up to 40,000K s-1, has been used to study the crystallization of amorphous Ge2Sb2Te5 with and without sandwich layers of ZnS-SiO2. At heating rates up to 1000K s-1, the sandwich layers retard crystallization, an effect attributed to crystallization-induced stress. At greater heating rates (&gt;or = 5000K s-1), and consequently higher crystallization temperatures, the stress is relaxed, and sandwich layers catalyze crystallization. Implications for memory-device performance are discussed

    Effects of Vortex Pinning on the Temperature Dependence of the Magnetic Field Distributions in Superconductors

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    The temperature and applied-magnetic-field dependence of the second moments of the magnetic-field distributions as measured by mu SR for YBCO and BSCCO have been fit for four different intrinsic-field-distribution models (d-wave, 2-fluid, empirical, and BCS). It is found that if a pinning potential becomes important at about 20 K, all of the models can fit the data reasonably well. The fits and the associated fitting parameters are presented

    The necessity of historical inquiry in educational research: the case of Religious Education

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    publication-status: PublishedThis is an Author's Original Manuscript of an article whose final and definitive form, the Version of Record, has been published in the British Journal of Religious Education, July 2010. Available online at: http://www.tandfonline.com/ or DOI: 10.1080/01416200.2010.498612This article explores the mixed fortunes of historical inquiry as a method in educational studies and exposes evidence for the neglect of this method in religious education research in particular. It argues that historical inquiry, as a counterpart to other research methods, can add depth and range to our understanding of education, including religious education, and can illuminate important longer‐term, broader and philosophical issues. The article also argues that many historical voices have remained silent in the existing historiography of religious education because such historiography is too generalised and too biased towards the development of national policy and curriculum and pedagogical theory. To address this limitation in educational research, this article promotes rigorous historical studies that are more substantially grounded in the appropriate historiographical literature and utilise a wide range of original primary sources. Finally, the article explores a specific example of the way in which a historical approach may be fruitfully applied to a particular contemporary debate concerning the nature and purpose of religious education

    The Williams Scale of Attitude toward Paganism: development and application among British Pagans

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    This article builds on the tradition of attitudinal measures of religiosity established by Leslie Francis and colleagues with the Francis Scale of Attitude toward Christianity (and reflected in the Sahin-Francis Scale of Attitude toward Islam, the Katz-Francis Scale of Attitude toward Judaism, and the Santosh-Francis Scale of Attitude toward Hinduism) by introducing a new measure to assess the attitudinal disposition of Pagans. A battery of items was completed by 75 members of a Pagan Summer Camp. These items were reduced to produce a 21-item scale that measured aspects of Paganism concerned with: the God/Goddess, worshipping, prayer, and coven. The scale recorded an alpha coefficient of 0.93. Construct validity of the Williams Scale of Attitude toward Paganism was demonstrated by the clear association with measures of participation in private rituals

    Attentive Learning of Sequential Handwriting Movements: A Neural Network Model

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    Defense Advanced research Projects Agency and the Office of Naval Research (N00014-95-1-0409, N00014-92-J-1309); National Science Foundation (IRI-97-20333); National Institutes of Health (I-R29-DC02952-01)

    Grain refinement of magnesium alloys: a review of recent research, theoretical developments and their application

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    This paper builds on the ‘‘Grain Refinement of Mg Alloys’’ published in 2005 and reviews the grain refinement research onMg alloys that has been undertaken since then with an emphasis on the theoretical and analytical methods that have been developed. Consideration of recent research results and current theoretical knowledge has highlighted two important factors that affect an alloy’s as-cast grain size. The first factor applies to commercial Mg-Al alloys where it is concluded that impurity and minor elements such as Fe and Mn have a substantially negative impact on grain size because, in combination with Al, intermetallic phases can be formed that tend to poison the more potent native or deliberately added nucleant particles present in the melt. This factor appears to explain the contradictory experimental outcomes reported in the literature and suggests that the search for a more potent and reliable grain refining technology may need to take a different approach. The second factor applies to all alloys and is related to the role of constitutional supercooling which, on the one hand, promotes grain nucleation and, on the other hand, forms a nucleation-free zone preventing further nucleation within this zone, consequently limiting the grain refinement achievable, particularly in low solute-containing alloys. Strategies to reduce the negative impact of these two factors are discussed. Further, the Interdependence model has been shown to apply to a broad range of casting methods from slow cooling gravity die casting to fast cooling high pressure die casting and dynamic methods such as ultrasonic treatment

    Volume I. Introduction to DUNE

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    The preponderance of matter over antimatter in the early universe, the dynamics of the supernovae that produced the heavy elements necessary for life, and whether protons eventually decay—these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our universe, its current state, and its eventual fate. The Deep Underground Neutrino Experiment (DUNE) is an international world-class experiment dedicated to addressing these questions as it searches for leptonic charge-parity symmetry violation, stands ready to capture supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector technical design report (TDR) describes the DUNE physics program and the technical designs of the single- and dual-phase DUNE liquid argon TPC far detector modules. This TDR is intended to justify the technical choices for the far detector that flow down from the high-level physics goals through requirements at all levels of the Project. Volume I contains an executive summary that introduces the DUNE science program, the far detector and the strategy for its modular designs, and the organization and management of the Project. The remainder of Volume I provides more detail on the science program that drives the choice of detector technologies and on the technologies themselves. It also introduces the designs for the DUNE near detector and the DUNE computing model, for which DUNE is planning design reports. Volume II of this TDR describes DUNE\u27s physics program in detail. Volume III describes the technical coordination required for the far detector design, construction, installation, and integration, and its organizational structure. Volume IV describes the single-phase far detector technology. A planned Volume V will describe the dual-phase technology

    Selective Exposure to Berita Harian Online and Utusan Malaysia Online: The Roles of Surveillance Motivation, Website Usability and Website Attractiveness

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    News media allows audiences to be selective in determining both their news sources and type of news stories they read. This study examined factors influencing selective exposure to the online editions of two mainstream Malaysian newspapers, Berita Harian and Utusan Malaysia. Using selective exposure theory as the theoretical lens, this study compared both newspapers in terms of their audiences’ level of surveillance motivation, and how audiences rate the newspapers’ websites with respect to usability and attractiveness. This study used a within-subject experimental research design that exposed 51 subjects to both Berita Harian and Utusan Malaysia online newspapers. The results of the experiment indicate that Berita Harian and Utusan Malaysia online were significantly different in terms of website usability; however, no significant differences were found in terms of surveillance motivation or website attractiveness between the two newspapers. Further analysis indicate that the only significant predictor of selective exposure was website usability. This study highlights the importance of website usability for online newspapers wanting to harness audience selectivity
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