1,721,002 research outputs found
Estimações das temperaturas no torneamento usando problemas inversos em medições por termovisor e termopares
Get PDFMachining plays an important role in the manufacturing of mechanical parts. This work
analyzes specifically the turning, which is one type of the machining processes. When it is
studied the general aspect of turning, one realizes high efforts acting on the cutting zone. The
high efforts along with the small dimensions of the insert-chip contact area contribute to the
development of high cutting temperatures. Furthermore, the temperature is an important factor
associated with the wear of cutting tools. The focus of the work was to analyze the
temperatures developed at the insert-chip interface. It was used in the analysis a model
assembling the shim, tool holder, clamp and cutting tool. This model was represented threedimensionally. The solution of the problem was divided into two parts: one applying inverse
techniques, and another with the solution of the direct problem. It was used as inverse
techniques the Nonlinear Function Specification Method (NFSM) and the Time Traveling
Regularization (TTR). These techniques were applied by using LiveLink for MATLAB®,
which integrates COMSOL® with MATLAB®. The direct solution of the problem relates to
solving the three dimensional non-linear transient diffusion equation. Among the boundary
conditions of the direct problem, one is the heat flux imposed at the insert-chip contact area.
This heat flux is essential for the solution of the problem. In general, this heat flux allows the
direct problem to estimate temperatures; these estimations are then applied into the inverse
problem and compared to experimental values of temperature. Comparing the estimated
temperatures with the experimental ones provided new information about the heat flux, which
was updated and again used into the direct problem. For the experiments it was used an insert
of cemented carbide. Thermocouples and a thermal imaging camera were used for
temperature measurements. The results of the simulations were analyzed and compared to
experimental values. Comparisons were made between the heat flux values estimated by the
NFSM and by the TTR. In addition were highlighted the differences in estimations regarding
the use of thermal camera or thermocouples in the inverse problem approach.A usinagem desempenha um papel importante na fabricação de peças mecânicas. Este
trabalho analisa especificamente o torneamento, o qual é um dos processos de usinagem.
Quando se analisa o aspecto geral no torneamento percebe-se altos esforços atuando na região
de corte. Os altos esforços junto às pequenas dimensões do contato cavaco-ferramenta
contribuem no desenvolvimento de altas temperaturas de corte. Além disso, a temperatura é
um fator crucial associado ao desgaste da ferramenta. O foco deste trabalho foi de analisar as
temperaturas na interface cavaco-ferramenta. O modelo tridimensional de análise para as
temperaturas agrupava o calço, o suporte da ferramenta, o grampo e a ferramenta. A solução
do problema foi divida em duas partes: uma aplicando técnicas inversas, e a outra com a
solução do problema direto. As técnicas inversas usadas foram a Função Especificada Não
Linear e a Regularização de Viagem no Tempo. Essas técnicas foram aplicadas através da
ferramenta LiveLink que integra o COMSOL® e o MATLAB®. A solução direta do problema
envolve resolver a equação da difusão de calor tridimensional não linear em regime
transiente. Dentre as condições de contorno do problema direto encontra-se a de fluxo de
calor imposto no contato cavaco-ferramenta. Esse fluxo de calor desempenha um papel
fundamental na resolução do problema. Em aspectos gerais, esse fluxo de calor permitia ao
problema direto fornecer estimações de temperaturas que eram comparadas com os valores
experimentais. Na experimentação foi usada uma ferramenta de metal duro. Termopares e
uma câmera termográfica foram os responsáveis pelas medições das temperaturas. Os
resultados das simulações foram analisados e comparados com os valores obtidos
experimentalmente. Realizou-se uma comparação entre os fluxos de calor estimados pela
Função Especificada Não Linear e pela Regularização de Viagem no Tempo. Também
pontuou-se diferenças quanto ao uso de câmera térmica ou termopares na abordagem do
problema inverso
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Monensin poisoning in sheep in Uruguay
Get PDFLa monensina es un antibiótico del grupo de los ionóforos utilizado como coccidiostático y promotor de crecimiento en los animales domésticos. El objetivo del presente trabajo es describir tres focos de intoxicación por monensina en ovinos ocurridos en los años 2015 y 2016. Todos los focos ocurrieron en predios ovejeros-ganaderos de la región Este de Uruguay. Los principales síntomas clínicos fueron anorexia, rigidez, paresia del tren posterior, y finalmente decúbito costal. A la necropsia los principales hallazgos fueron edema subcutáneo generalizado, hidrotórax, hidroperitoneo e hidropericardio, y en un caso la orina tenía una coloración rojiza. Las masas musculares del tren posterior estaban pálidas y edematosas en todos los casos, mientras que se observó palidez en el músculo cardíaco en un caso. Las principales lesiones histológicas fueron degeneración y necrosis de músculo esquelético y cardíaco. Se concluye que la intoxicación por monensina en ovinos ocurre por la utilización de raciones o sales formuladas para bovinos y por errores en las plantas elaboradoras de raciones comerciales.Monensin is an antibiotic widely used in domestic animals. The aim of this paper is to describe three monensin poisoning outbreaks in sheep, occurred in 2015 and 2016, in the eastern region of Uruguay. The main clinical symptoms were anorexia, rigidity, hindlimb paresis, and finally lying sack. At necropsy the main findings were generalized subcutaneous edema, hydrothorax, hydroperitoneum and hydropericardium. In one case the urine had a reddish color. The hindlimb muscle masses showed pallor in all cases, while paleness in the heart muscle was observed in one case. The main histological lesions were degeneration and necrosis of skeletal and cardiac muscle. It is concluded that monensin poisoning in sheep occurs by the use of rations or salts formulated for cattle and by errors in commercial ration processing plants.Fil: Romero, Agustín.. No especifíca;Fil: García, Juan Agustín. Universidad de la Republica; Uruguay. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Dutra, Fernando. No especifíca
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
- …
