309,539 research outputs found
Holografia digital complexa utilizando um interferômetro shearing
No full textTese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Mecânica.A evolução das câmeras CCD e sistemas de processamento de imagens viabilizaram o desenvolvimento da holografia digital. O filme fotográfico pôde ser substituído por sensores CCD de elevada resolução, capazes de registrar os complexos padrões de interferência. A reconstrução do holograma é efetuada inteiramente de forma digital, sendo possível registrar com precisão pequenos campos de deslocamentos e deformações. Na holografia clássica, assim como na holografia digital e na holografia digital complexa um fator limitante que inviabiliza medições em campo é a elevada sensibilidade às perturbações externas do arranjo holográfico. É fundamental que o arranjo seja isolado de perturbações externas, o que torna a prática destas medições restrita a um ambiente de laboratório. A nova configuração proposta neste trabalho utiliza um interferômetro "shearing" para produzir uma onda de referência implícita. A informação de intensidade e a informação de fase são utilizadas para a reconstrução da frente de onda. O holograma resultante deste processo está sendo denominado "holograma digital complexo". Este trabalho apresenta em detalhes o princípio da nova configuração. Diferentes algoritmos foram criados e testados para o cálculo do "holograma digital complexo". Experimentos monitorados foram realizados e demonstram a viabilidade da técnica para futuras aplicações para a medição de deslocamentos
Interview with George Shearing / interviewed by Felix Grant, April 4, 1968
No full textGeorge Shearing discusses his career with interviewer and radio host Felix Grant. Shearing is featured on excerpts from recordings selected by Grant.Made available in DSpace on 2012-10-09T17:39:49Z (GMT). No. of bitstreams: 2
shearing_george1.rm: 71923560 bytes, checksum: e0c002335d42a75154f864c20f4e13d9 (MD5)
manifest.xml: 3423 bytes, checksum: 0181b1e2e67c87efdf7011c6c9a7da0e (MD5)George Shearing interviewed by Felix Grant on WMAL. Recorded April 4, 1968. Reproduction of radio interview produced at Washington, D.C. Station WMAL for broadcast on The Album Sound. Forms part of the Felix Grant Collection at the Felix E. Grant Jazz Archives. Original format: 1 sound tape reel (1 hr. 33 min.) : analog, 7 1/2 ips., fulll track mono; 7 in
Enhanced heterogeneous nucleation on oxides in Al alloys by intensive melt shearing
No full textThis thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Aluminium alloys, including both foundry and wrought alloys, have been extensively used for light-weight structural and functional applications. A grain refined as-cast microstructure is generally highly desirable for either subsequent processing ability or mechanical properties of the finished components. In this thesis, the grain refined microstructures in Al alloys have been achieved by intensive melt shearing using the melt conditioning by advanced shearing technology (MCAST) without deliberate grain refiner additions. Such grain refinement has been attributed to the enhanced heterogeneous nucleation on the dispersed oxide particles. It has been established that the naturally occurring oxides in molten Al alloys normally have a good crystallographic match with the a-Al phase, indicating the high potency of oxide particles as the nucleation sites of the a-Al phase. The governing factors for these oxide particles to be effective grain refiners in Al alloys have been proposed, including the achievement of good wetting between oxide particles and liquid aluminium, a sufficient number density and uniform spatial distribution of the dispersed oxide particles, and near equilibrium kinetic conditions in liquid alloys. In the present study, near equilibrium kinetic conditions can be achieved by intensive melt shearing using a twin screw mechanism, which has been confirmed by the observed equilibrium a-AlFeSi phase in a cast Al alloy and the transformation from g- to a-Al2O3 at 740±20oC under intensive shearing. For different alloy systems, depending on the alloy system, and melting conditions, due to the particular types of oxide formed and its crystallographic and chemical characteristics, the nucleation site of the nucleated phase is different. Specifically, MgAl2O4 relative to MgO, and a-Al2O3 relative to g-Al2O3, have higher potency as heterogeneous nucleation sites of a-Al phase in Al alloys. In future, the modification of the crystallographic match, and of the other surface characteristics related to the interfacial energy between the specific oxides and nucleated phase by trace alloying addition through segregation to the interface between oxides and nucleated phases combined with physical melt processing (such as intensive shearing in the present study) should be investigated in more detail.This study was funded by the EPSRC and Norton Aluminium Limited, UK
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Insurance and climate change
No full textThis chapter uses a desktop study to examine the insurance industry’s potential as a ‘fulcrum institution’ that can influence others to prevent and address environmental harms from climate change. As this chapter demonstrates, given insurance’s central economic role, the relationship between insurers and climate change is complicated and conflicted. After the discussion of insurers as shapers of climate risk (the first section of the chapter), this chapter explains how (in the second section) insurers are strongly implicated in creating climate change and attendant climate risk in the period since industrialisation through facilitating the accelerating fossil-fuel-based economic development and growth that causes climate change; this is the dominant dimension in insurers’ relationship with climate change. In the third section of this chapter, the authors review insurers’ responses over the past decade to increasing climate risk. Responses have been largely adaptive and aimed at increasing insurers’ capacity to accommodate the climate risks faced by their policyholders. Some responses have been ‘weakly mitigative’, meaning that they provide for some mitigation, but on a very limited scale, and largely as side effects of initiatives unrelated to climate change. In marked contrast, a very limited number of recent ‘divest and decline’ actions by insurance industry actors can be described as ‘strongly mitigative’, as described in the fourth section. The fifth section concludes the chapter with some remarks on the prospects for further strong mitigation action from insurers on climate change and their role as governors of security beyond the state
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Sheep shearing
No full textPortable shearing plant west of New Castle shearing Earl Clark's sheepPhotograph
A Deep-sea Soft Sediments Shearing Strength-Shearing Displacement Model
No full textThe shearing strength-shearing displacement model of deep-sea soft sediments is quite important to predict the traction and slip ratio of nodule collector. According to the physical mechanics characters of the deep-sea soft sediments, the 321 sodium molybdate swell soil samples are selected as the preparation materials of the deep-sea soft sediments, and the demixion preparation method is adopted to simulate the deep-sea soft sediments in the lab. Â The results of experiment validate that the simulated deep-sea soft sediments have the representative shearing strength-shearing displacement character of brittle soils. Five shearing strength-shearing displacement models of brittle soils are analyzed and the shearing strength-shearing displacement model being the same with the deep-sea soft sediments based on maximum shearing strength, residual shearing strength, and elastic modules is established, which can offer theoretical support for the structure optimization of running track and the enhancement of the running performance
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LAMB SHEARING
No full textThis video is about lamb shearing. Torghut herders shear their lambs in early June. Herders believe that shearing lamb wool helps them have less wool during the hot summer and prevents them from various parasites. In the past, herders utilised lamb wool to make felts for their yurts. Nowadays, herders mostly shear the lambs and sell the wool at cheap prices. There are only a few people who utilise lamb wool nowadays
Author, publisher and bookseller : a tripartite synergy in Nigerian book industry
No full textThis work is about the roles of Author, Publisher and Bookseller in Book development in
Nigeria. The paper started by delving into the history of Book Publishing in Nigeria after
which it proceeded by defining who an author, a publisher, and a bookseller is and
expatiated on the indispensable roles of these key actors in Nigerian Book Industry and in
the emerging Information Society. Furthermore, the various constraints to book
development were identified while the paper advised on how the Book Industry can be
further promoted in Nigeria. However, the paper concluded and made recommendations
on how the Book sector can help in enhancing scholarship in the country
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