10,757 research outputs found
Expected performance of a self-coherent camera
No full textInternational audienceResidual wavefront errors in optical elements limit the performance of coronagraphs. To improve their efficiency, different types of devices have been proposed to correct or calibrate these errors. In this article, we study one of these techniques proposed by Baudoz et al. (2006), and called Self-Coherent Camera (SCC). The principle of this instrument is based on the lack of coherence between the stellar light and the planet that is searched for. After recalling the principle of the SCC, we simulate its performance under realistic conditions and compare it with the performance of differential imaging. To cite this article: R. Galicher, P. Baudoz, C. R. Physique 8 (2007)
Self-Coherent Camera: active correction and post-processing for Earth-like planet detection
No full textInternational audienceDetecting light from faint companions or protoplanetary disks lying close to their host star is a demanding task since these objects are often hidden in the overwhelming star light. A lot of coronagraphs have been proposed to reduce that stellar light and thus, achieve very high contrast imaging, which would enable to take spectra of the faint objects and characterize them. However, coronagraph performance is limited by residual wavefront errors of the incoming beam which create residual speckles in the focal plane image of the central star. Correction or calibration of the wavefront are then necessary to overcome that limitation. We propose to use a Self-Coherent Camera (SCC, Baudoz et al. 2006). The SCC is one of the techniques proposed for EPICS, the futur planet finder of the European Extremely Large Telescope but can also be studied in a space telescope context. The instrument is based on the incoherence between stellar and companion lights. It works in two steps. We first estimate wavefront errors to be corrected by a deformable mirror and then, we apply a post-processing algorithm to achieve very high contrast imaging
“Enquête sur l’auteur. Entretien avec Pierre Bayard”
No full textInternational audience05/04/2019 “Enquête sur l’auteur. Entretien avec Pierre Bayard” [“Investigation into the Author. Interview with Pierre Bayard”], event for bachelor’s and master’s students in French and comparative literature, Lorraine University
Is There Market Power in the French Comte Cheese Market?
No full textAn NEIO approach is used to measure seller market power in the French Comté cheese market, characterised by government-approved supply control. The estimation is performed on quarterly data at the wholesale stage over the period 1985-2005. Three different elasticity shifters are included in the demand specification, and the supply equation accounts for the existence of the European dairy quota policy. The market power estimate is small and statistically insignificant. Monopoly is rejected, as well as weak forms of Cournot oligopoly. Results appear to be robust to the choice of functional form, and suggest little effect of the supply control scheme on consumer prices.Supply control, NEIO, protected designation of origin, Marketing,
The aesthetics of Pierre Boulez
No full textTo enable the reader to find references as quickly and easily as possible, I have grouped all references together in the bibliography in alphabetical order. Texts by the same author are distinguished first by year and second, if there are several texts from the same year, by letter. Interviews and writing collaborations (including published correspondence) involving Boulez are also ordered alphabetically. The year given at the beginning of each bibliographical entry is, in the majority of cases, the year in which the text was first published (not necessarily the year of the edition cited). For all writings written by Boulez, I have provided the original title under which the text in question was first published (usually in French). Many articles have subsequently been translated into English and therefore I have decided to provide page references for both versions. For all texts by writers other than Boulez, I have cited the version of the text I have used. Wherever possible, I have cited the existing English translations of texts originally written in French. However, on many occasions I have considered it necessary to make alterations to the published translations. This is particularly applicable to Boulez on Music Today (1971) and Orientations (1986), both of which display an often heavy-handed and rather inaccurate approach to the task of translating specific concepts employed by Boulez. In contrast. Stocktakings of an Apprenticeship (1991) has required only occasional minor amendments. All changes to the published English translations are acknowledged in the corresponding footnote. None of the material m this thesis has previously been submitted for a degree in this or any other University. The copyright of this thesis rests with the author. No quotation from it should be published without prior written consent and information from it should be acknowledged. I have received permission to exceed the word limit from the Graduate School Committee at the University of Durham
Etnografia e fotografia: reflexões sobre as fotografias etnográficas de Pierre Fatumbi Verger
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências Humanas. Programa de Pós-graduação em Antropologia Social, Florianópolis, 2009A relação entre a fotografia e a etnografia nos estudos da Antropologia, apesar de antiga e densa, é incerta e complexa. Se por um lado a fotografia é a cada dia mais utilizada nos trabalhos antropológicos, por outro sua potencialidade como algo além da ilustração e de uma técnica de interação com o Outro é pouco explorada. A partir do exemplo, do legado, da trajetória de vida e, principalmente, da obra de Pierre Fatumbi Verger, esta pesquisa se dedica a analisar essa relação. Francês radicado na Bahia na década de 1940, Verger é conhecido mundialmente tanto por seu trabalho como fotógrafo quanto pelas suas pesquisa etnográficas. Há, entretanto, uma indefinição quanto à razão desse reconhecimento, e examinar as suas razões oferece um profícuo campo de reflexão sobre a pesquisa etnográfica, especialmente quando relacionada ao universo das imagens fotográficas. A Fundação Pierre Verger é a instituição que atualmente abriga o acervo do fotógrafo-etnógrafo e onde foi realizada a pesquisa de campo através da qual, aliada à leitura de fotografias relacionadas ao candomblé em suas manifestações na África e na Bahia, foi criada uma metodologia de análise das fotografias que privilegia as interações e os diálogos como espaço de construção de definições sobre a etnografia. Pelo contato com a Fundação, seus freqüentadores e o acervo fotográfico ali disponibilizado, esta pesquisa pretende refletir sobre a etnografia e a construção de um olhar etnográfico em relação direta com o exercício da fotografia.The relationship between photography and ethnography in anthropological studies, albeit ancient and deep, is uncertain and complex. Photography has been increasingly used in anthropological researches but it´s potencial as something beyond illustration and it´s interaction with the Other as a technique is very little explored. This research is dedicated to the analysis of this relationship by taking the work of Pierre Fatumbi Verger, his life and legacy. A French man, rooted in Bahia, Brasil, in the decade of 1940, Verger is known worldwide for his work as a photographer as well as for his etnographic studies. However, the reason of this recognition is undefined and examining the reason for these indefinitions can be a fruitful field of reflection concerning ethnographic researches, especially when related to the photographic universe. The Pierre Verger Foundation is the institution that hosts his photographic and ethnographic collection and it´s also where the field research of this work took place. Through the field research combined with the readings of photographs related to candomblé and it´s manifestations in Africa and Bahia, a photographic analysis methodology was created that privilege interaction and dialogue as a way to build definitions about ethnography. By the contact with the Foundation, it´s users and it´s available photographic collection, this research intends to reflect about the ethnography and the creation of an ethnographic view in direct relation to the exercise of photography
A Emergência Do Autor Pierre Rivièrethe Emergence Of The Pierre Rivière Author
No full textNesse artigo apresento uma análise do caso de parricídio / fraticídio cometido por um jovem camponês francês, nascido na comuna de Courvaudon, Pierre Rivière que em 3 de junho de 1835, aos vinte anos, assassinou a golpes de foice sua mãe grávida de sete meses, sua irmã de 18 anos, e seu irmão de sete anos. O livro intitulado Eu, Pierre Rivière, que degolei minha mãe, minha irmã e meu irmão produzido pelo trabalho de uma equipe de pesquisadores, no Collège de France, sob a coordenação de Michel Foucault em 1973, apresenta em seu conjunto notícias de jornais, testemunhos, interrogatórios, laudos médicos e uma gama de diferentes discursos. Para empreender a análise do nó entre a escrita e o assassinato, utilizo a relação entre a escrita e o autor demarcando o personagem Rivière no desdobramento, na ordem do corpo e da linguagem. Palavras-chave Função autor; Corpo; Linguagem; Pierre Rivière; Michel Foucault Abstract This paper has as aim to present an analysis of the case of patricide / fratricide cometed by a French Countryman, Pierre Rivière, who was born in the commune of Courvaudon, who, on July 3rd, 1835, at age of 20, killed his mother, his brother and sister with a sickle. His mother was in the seventh month of pregnancy, his sister was 18 and his brother was 7 years old. The book, whose name was “I, Pierre Riviere, Having Slaughtered My Mother, My Sister, and My Brother ...: A Case of Parricide in the Nineteenth Century” was produced by a group of researchers at the Collège de France, under the coordination of Michel Foucault in 1973, has a set of newspaper news, witnesses, inquiring, forensic medical reports and a variety of different texts. To understand and analyze the writings and the homicide, the relationship between writing and the author is used, marking the character Rivière unfolding body and language. Keywords Function author; Body; Language; Pierre Rivière; Michel Foucault80227-24
A emergência do autor Pierre RivièreThe emergence of the Pierre Rivière author
No full textNesse artigo apresento uma análise do caso de parricídio / fraticídio cometido por um jovem camponês francês, nascido na comuna de Courvaudon, Pierre Rivière que em 3 de junho de 1835, aos vinte anos, assassinou a golpes de foice sua mãe grávida de sete meses, sua irmã de 18 anos, e seu irmão de sete anos. O livro intitulado Eu, Pierre Rivière, que degolei minha mãe, minha irmã e meu irmão produzido pelo trabalho de uma equipe de pesquisadores, no Collège de France, sob a coordenação de Michel Foucault em 1973, apresenta em seu conjunto notícias de jornais, testemunhos, interrogatórios, laudos médicos e uma gama de diferentes discursos. Para empreender a análise do nó entre a escrita e o assassinato, utilizo a relação entre a escrita e o autor demarcando o personagem Rivière no desdobramento, na ordem do corpo e da linguagem.
Palavras-chave
Função autor; Corpo; Linguagem; Pierre Rivière; Michel Foucault
Abstract
This paper has as aim to present an analysis of the case of patricide / fratricide cometed by a French Countryman, Pierre Rivière, who was born in the commune of Courvaudon, who, on July 3rd, 1835, at age of 20, killed his mother, his brother and sister with a sickle. His mother was in the seventh month of pregnancy, his sister was 18 and his brother was 7 years old. The book, whose name was “I, Pierre Riviere, Having Slaughtered My Mother, My Sister, and My Brother ...: A Case of Parricide in the Nineteenth Century” was produced by a group of researchers at the Collège de France, under the coordination of Michel Foucault in 1973, has a set of newspaper news, witnesses, inquiring, forensic medical reports and a variety of different texts. To understand and analyze the writings and the homicide, the relationship between writing and the author is used, marking the character Rivière unfolding body and language.
Keywords
Function author; Body; Language; Pierre Rivière; Michel Foucaul
Les futures missions spatiales dédiées aux planètes extrasolaires
No full textAvec 4000 planètes découvertes en 20 ans dont plus de la moitié dans les trois dernières années, l’étude des planètes extrasolaires est devenue un thème majeur de l’astronomie moderne. La découverte de planètes différentes de celles observées dans notre système solaire interroge les modèles de formation et d’évolution des systèmes planétaires. Pour bien comprendre la nature de ces nouveaux objets, les données actuelles sont trop limitées et des grands projets notamment spatiaux seront nécessaires dans les années qui viennent
Future Exoplanet Research: High-Contrast Imaging Techniques
No full textInternational audienceHigh-contrast imaging (HCI) techniques appear like the best solutions to directly characterize large orbit planets and planetary environments in the future. The first dedicated scientific instruments like SPHERE on VLT and GPI on Gemini South have only been commissioned in 2013-2014. HCI is thus a rather young field of research, still very prolific with a lot of technical solutions proposed to improve the actual instrument concepts. A lot of new technical solutions have been recently proposed to improve actual instrument concepts. Since most of them have not yet been tested at the expected level of performance and/or in real conditions, it is rather difficult to define precisely which solutions will be the most efficient scientifically with respect to the future technical, environmental, and operational constraints. Among these different solutions, I will describe and discuss the main directions of development required to optimize the future HCI instruments on speckle suppression, wavefront correction, and detection methods
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