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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

[en] ANYTHING INTERMEDIATE: INTERTEXTUALITY IN THE WORK OF ADRIANA CALCANHOTTO / [pt] QUALQUER COISA DE INTERMÉDIO: INTERTEXTUALIDADE NA OBRA DE ADRIANA CALCANHOTTO

FLAVIA IRIARTE TORTIMA 22 May 2017 (has links)
[pt] Essa pesquisa é o resultado de um estudo sobre a figura e a obra de Adriana Calcanhotto. Cantora, letrista e compositora brasileira, seu trabalho vem se caracterizando, sobretudo, por transitar nas fronteiras entre o erudito e o popular, a arte de vanguarda e a cultura de massa. Suas realizações vão desde musicar poemas de Carlos Drummond de Andrade, Waly Salomão, Antonio Cícero, Ferreira Gullar, Mário de Sá-Carneiro, Haroldo e Augusto de Campos e vestir os Parangolés de Hélio Oiticica (artistas relacionados à arte de vanguarda), até gravar canções relacionadas à tradição do kistch e do brega, consumidas em larga escala através dos meios de comunicação de massa. O movimento dessa artista nos faz pensar imediatamente na reflexão proposta por José Miguel Wisnik em seu conhecido ensaio A Gaia Ciência, em que o ensaísta e compositor defende a música popular brasileira enquanto espaço legítimo de construção de saber. Dessa forma, procuro pensar o trabalho de Adriana a partir dessa ótica, sinalizando esse espaço lúdico que a artista constrói, capaz de articular conhecimento e sensibilidades. Para tal, procuro analisar letras de canções, figurinos, cenários e repertórios de show, declarações dadas à imprensa etc. Em uma segunda etapa, reflito acerca do paradoxal processo (para o qual aponta Antoine Compagnon) de dessacralização da arte e fetichização do autor na modernidade, e que se acentua no cenário contemporâneo, em que o artista passa a atuar na construção de uma imagem (de uma persona artística), transformando o próprio corpo também em suporte artístico. Nesse cenário, atravessado permanentemente pela mídia e pela exposição, em que noções de público e privado, essência e aparência, se confundem, nublam-se também as fronteiras entre arte e vida. / [en] This research is the result of a study of the figure and work of brazilian composer Adriana Calcanhotto. Singer, lyricist and composer, her work has been characterized mainly by transit at the borders between the classical and popular, the mass culture and avant-garde art, with achievements ranging from poems set to music by Carlos Drummond de Andrade, Waly Solomão, Antonio Cicero, Ferreira Gullar, Mário de Sá-Carneiro, Haroldo and Augusto de Campos, and wear the Parangolés of Hélio Oiticica (artists related to avant-garde art), recording songs related to tradition and kistch s corny, consumed largely by the means of mass communication. The movement of this artist makes us think immediately in the discussion launched by José Miguel Wisnik known in his essay A Gaia Ciência, in which the essayist and songwriter of brazilian popular music advocates as legitimate space for building knowledge. Thus, I reflected of the work of Adriana from that perspective, signaling this playful space that the artist builds, able to articulate knowledge and sensitivities. To this end, I analyze the lyrics to songs, costumes, sets and repertoires show, speaking to the press etc. In a second step, I intend to reflect on the paradoxical process (pointed by Antoine Compagnon) of desecration of art and the modern fetishization of the author, and which increases in the contemporary scene, in which the artist goes to work on building an image (an artistic persona), transforming their bodies also artistic support. In this scenario, constantly traversed by the media and by exposure, in which notions of public and private essence and appearance, are confused, clouds are also the boundaries between art and life.
52

Integration of multi-criteria tools in geographical information systems / Intégration d'outils multicritères dans les systèmes d'information géographique

Lidouh, Karim 13 January 2014 (has links)
For a little over twenty years, researchers have worked on integrating multi-criteria aggregation procedures (MCAP) to GIS. Several notable contributions have brought this field to what it is today. After studying the course of MCDA-GIS integration through several works, we question the future of such an attempt. Indeed most works that aim for an integration do not survive long after their direct purpose has been fulfilled. We end up understanding through a critical review of the existing systems that technical integration means nothing if it is not visible to the user on an operational level.<p><p>We therefore propose several contributions to improve the usability of MCDA methods in a geographic context. One of our works consists in adapting the PROMETHEE-GAIA methodology to be used on maps for spatially referenced problems. To do so, we define symbols/glyphs that display select parts of the results obtained through the PROMETHEE and GAIA methods. This allows for the comparison of alternatives' profiles and characteristics based on their geographic location which wasn't possible before. This adaptation helps us combine multicriteria and geographic aspects in an entirely new way.<p>We also propose some extensions of the GAIA method to improve the quality of the results and reduce the risk of wrong interpretations to be made due to losses of data. / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished
53

Effects of stellar surface inhomogeneities on astrometric accuracy / Effets des inhomogénéités de surface stellaire sur la précision astrométrique

Pasquato, Ester 13 September 2011 (has links)
Surface brightness asymmetries are a very common feature of stars. Among other effects they cause a difference between the projected centre of mass and the photocentre. The evolution of those surface features makes this difference time-dependent. In some cases the displacement can be a non-negligible fraction of the star radius R, and if R>1 AU, of the parallax. We investigate the impact of surface brightness asymmetries on the Gaia astrometric solution and on the data processing flow. In particular we derive analytical expressions for the change in the derived astrometric parameters for a single-star, with respect to the parameters for a uniformly-bright star, as a function of the characteristics of the surface brightness asymmetries. These predictions are confirmed by the results of the processing of simulated astrometric Gaia data where a photocentre motion caused by surface brightness asymmetries has been added using a Gaussian Markovian model.<p>In the case of a red supergiant star, the average photocentre shift is about 0.1 AU. Such a photocentric noise translates in a 10% inaccuracy on the parallax (independently of the distance), which becomes larger than the statistical error on the parallax derived from the data reduction for stars that are up to about 4 kpc away. For the most nearby stars, we derive an inaccuracy on the parallax that can be 10 times its statistical error. Finally we estimate that up to about 4000 stars among red supergiants and bright giants may have astrometric parameters that are inaccurate at levels bigger than expected because of the surface brightness asymmetries. In the determination of this number, a crucial role is played by the Gaia observable magnitude range. The fact that Gaia will not observe stars brighter than 5.6 in the Gaia G band means that the closest stars will not be observed. Yet, the impact of the surface brightness asymmetries is proportional to their angular size, meaning that the stars whose astrometric accuracy would be most affected are not observed.<p>Various non-Gaussian spot models (as applicable in the case of magnetic spots) have been implemented and analytical predictions for the effects of such magnetic spots are computed for the most representative classes of magnetic stars.<p>Another effect of the presence of surface brightness asymmetries is their impact on Gaia data processing flow. The quality of the fit of the data is evaluated with the F2 parameter that is a transformation of χ2 such that it has a unit normal distribution when the model is adequate and it is independent of the number of measurements. If the goodness-of-fit F2 of the single-star solution is not good enough (F2>3), a chain of solution of growing complexity is tried until a satisfactory one (with F2<3) is obtained. If no good solution is found, a so-called stochastic solution is computed where a "cosmic" error is added to the data in order to obtain a single-star solution with F2=0. We show that the photocentre noise induces an increase in the goodness-of-fit parameter, causing this chain of solutions to be entered. Depending on the characteristics of the photocentre noise, a variable fraction of the stars in our simulations end up with a non-single-star solution. Yet, we show that these (orbital) solutions are not acceptable because non-significant or non-physical. Finally, an important fraction of stars is assigned a stochastic solution with a cosmic noise matching well the photocentric noise.<p><p>/<p><p>Les asymétries de brillance de surface sont une caractéristique commune des étoiles. Parmi d'autres effets, elles provoquent une différence entre la projection du centre de masse et le photocentre. L'évolution de ces structures de surface rend cette différence variable avec le temps. Dans certains cas, le déplacement du photocentre peut être une fraction non négligeable du rayon de l'étoile R et, si R>1 UA, de la parallaxe. Nous examinons l'impact des asymétries de brillance de surface sur la solution astrométrique de Gaia et sur le processus de traitement des données. En particulier nous dérivons des expressions analytiques pour le changement des paramètres astrométriques déerivées pour une étoile simple, par rapport aux paramètres pour une étoile uniformément lumineuse, en fonction des caractéristiques des asymétries de brillance de surface. Ces prévisions sont confirmées par les résultats de simulations du traitement des données astrométriques de Gaia, auxquelles des mouvements du photocentre causés par des asymétries de brillance de surface ont été ajoutés en utilisant un modèle gaussien markovien.<p><p>Dans le cas d'une étoile super-géante rouge, le décalage moyen du photocentre est d'environ 0.1 UA. Un bruit photocentrique de cette amplitude se traduit dans une imprécision de 10% sur la parallaxe (indépendamment de la distance), qui peut devenir plus grande que l'erreur statistique sur la parallaxe déerivée par la réduction des données, pour les étoiles plus proches d'environ 4 kpc. Pour les étoiles les plus proches, nous évaluons une imprécision sur la parallaxe qui peut être 10 fois leur erreur statistique. Finalement, nous estimons que jusqu'à environ 4000 étoiles parmi les super-géantes rouges et géantes brillantes peuvent avoir des paramètres astrométriques inexactes à des niveaux plus grands que prévu en raison des asymétries de brillance de surface. Dans la détermination de ce nombre, la gamme de magnitudes observables par Gaia joue un rôle crucial. Le fait que Gaia n'observera pas les étoiles plus brillantes que 5.6 mag (en bande Gaia) signifie que les étoiles les plus proches ne seront pas observées. Pourtant, l'impact des asymétries de brillance de surface est proportionnel à leur taille angulaire, ce qui signifie que les étoiles dont la précision astrométrique seraient la plus affecté ne seront pas observées.<p>Différents modèles de taches ont été réalisés et des prédictions analytiques pour les effets de ces taches magnétiques sont calculés pour les classes les plus représentatives des étoiles magnétiques. <p>Un autre effet de la présence des asymétries de brillance de surface est leur impact sur le traitement des données de Gaia. La qualité de l'ajustement des données est évaluée avec le paramètre F2 qui est une transformation de χ2 telle qu'il ait une distribution normale lorsque le modèle est adéquat. Si la qualité de l'ajustement F2 de la solution étoile-simple n'est pas acceptable (F2>3), une chaîne de solutions de complexité croissante est essayée jusqu'à ce qu'une solution satisfaisante (avec F2<3) soit obtenue. Si aucune solution satisfaisante n'est trouvée, une solution dite stochastique est calculée où une erreur "cosmique" est ajoutée aux données afin d'obtenir une solution étoile-simple avec F2=0. Nous montrons que le bruit du photocentre induit une augmentation de F2, ce qui provoque l'activation de cette chaîne de solutions. Selon les caractéristiques du bruit du photocentre, une solution étoile-non-simple est obtenue pour une fraction variable des étoiles dans nos simulations. Nous montrons que ces solutions (orbitales) ainsi obtenues ne sont pas acceptables car non significatives ou non-physiques. Enfin, une fraction importante d'étoiles se voient attribuer une solution stochastique avec un bruit cosmique correspondant au bruit photocentrique. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
54

Ampliando horizontes da missão espacial Gaia graças à análise de objetos extensos / Plus loin avec la mission spatiale Gaia grâce à l\'analyse des objets étendus

Alberto Garcez de Oliveira Krone Martins 18 March 2011 (has links)
Ce travail a comme objectif principal de vérifier s\'il est possible de faire de la science avec les observations d\'objets étendus qui seront réalisées par la mission spatiale Gaia. Cette mission, l\'un des plus ambitieux projets de l\'Astronomie moderne, observera plus d\'un milliard d\'objets dans tout le ciel avec des précisions inédites, fournissant des données astrométriques, photométriques et spectroscopiques. Naturellement, en fonction de sa priorité astrométrique, Gaia a été optimisé pour l\'étude d\'objets ponctuels. Néanmoins, diverses sources associées à des émissions étendues seront observées. Ces émissions peuvent avoir une origine intrinsèque, telles que les galaxies, ou extrinsèque, telles que les projections d\'objets distincts sur la même ligne de visée, et présenteront probablement de solutions astrométriques moins bonnes. Pour étudier ces émissions, leurs images bidimensionnelles doivent être analysées. Néanmoins, comme Gaia ne produit pas de telles données, nous avons commencé ce travail en vérifiant si à partir de ses observations unidimensionnelles il serait possible de reconstruire des images 2D d\'objets dans tout le ciel. Nous avons ainsi estimé la quantité de cas sujets à la présence démissions étendues extrinsèques, et nous avons présenté une méthode que nous avons développée pour analyser leurs images reconstruites. Nous avons montré que l\'utilisation de cette méthode permettra détendre le catalogue final de façon fiable à des millions de sources ponctuelles dont beaucoup dépasseront la magnitude limite de l\'instrument. Dun autre coté, dans le cas démissions intrinsèques, nous avons premièrement obtenu une estimation supérieure du nombre de cas que Gaia pourra observer. Nous avons alors vérifié qu\'après les reconstructions d\'images, les codes que nous avons développés permettront de classifier morphologiquement des millions de galaxies dans les types précoce/tardif et elliptique/spirale/irrégulière. Nous avons de plus présenté une méthode que nous avons développée pour réaliser la décomposition bulbe/disque directement à partir des observations unidimensionnelles de Gaia de façon complètement automatique. Finalement nous avons conclu qu\'il est possible d\'utiliser beaucoup de ces données qui pourraient être ignorées pour faire de la science. Et que le fait de les exploiter permettra aussi bien la détection de millions d\'objets qui dépassent la limite de magnitude de Gaia, que de mener des études sur la morphologie de millions de galaxies dont les structures ne peuvent être révélées qu\'à partir de l\'espace ou au moyen d\'optique adaptative, augmentant un peu plus les horizons de cette mission déjà immense. / Este trabalho tem como objetivo principal verificar se é possível fazer ciência com as observações de objetos extensos que serão realizadas pela missão espacial Gaia. Um dos mais ambiciosos projetos da Astronomia moderna, essa missão observará mais de um bilhão de objetos em todo o céu com precisões inéditas, fornecendo dados astrométricos, fotométricos e espectroscópicos. Naturalmente, devido à sua prioridade astrométrica o Gaia foi optimizado para o estudo de objetos pontuais. Contudo, diversas fontes associadas a emissões extensas serão observadas. Essas emissões podem ter origem intrínseca, como galáxias, ou extrínseca, como projeções de objetos distintos na mesma linha de visada, e deverão ter soluções astrométricas aquém do ideal. Para estudar essas emissões suas imagens bidimensionais devem ser analisadas. Contudo, como o Gaia não obtém tais dados, iniciamos este trabalho verificando se a partir de suas observações unidimensionais seria possível reconstruir imagens de objetos em todo céu. Dessa forma, por um lado, nós estimamos a quantidade de casos sujeitos à presença de emissões extensas extrínsecas, apresentamos um método que desenvolvemos para segregar fontes astronômicas em imagens reconstruídas, e mostramos que sua utilização possibilitará estender o catálogo final de forma confiável em milhões de fontes pontuais, muitas das quais estarão além da magnitude limite do instrumento. Por outro lado, no caso de emissões intrínsecas, primeiro obtivemos uma es- timativa superior para o número de casos que o Gaia poderá observar. Então verificamos que após reconstruções de imagens, os códigos aqui desenvolvidos per- mitirão classificar morfologicamente milhões de galáxias nos tipos precoce/tardio e elíptico/espiral/irregular. Mostramos ainda um método que construímos para realizar a decomposição bojo/disco diretamente a partir das observações unidimensionais do Gaia de forma completamente automática. Finalmente concluímos que sim, é possível aproveitar muitos desses dados que poderiam ser ignorados para fazer ciência. E que salva-los possibilitará tanto a detecção de milhões de objetos além do limite de magnitude do Gaia, quanto estudos da morfologia de milhões de galáxias cujas estruturas podem ser apenas reveladas do espaço ou por meio de óptica adaptativa, expandindo um pouco mais os horizontes dessa já abrangente missão.
55

Identifying Gravitationally Lensed QSO Candidates with eROSITA

Brogan, Róisín O'Rourke January 2020 (has links)
As of June 2020, the first all-sky X-ray survey with the eROSITA instrument aboard the spacecraft Spektr-RG has been completed. A high percentage of the 1.1 million objects included in the survey are expected to be active galactic nuclei (AGN). Such an extensive catalogue of X-ray sources offers a unique opportunity for large scale observations of distinct classes of X-ray emitters. This report explores methods of refining the catalogue to include only candidates for lensed AGN. Of the differing types of AGN known, quasi-stellar objects, or QSOs, are some of the most luminous, meaning they are well-suited for observation over large distances. This is particularly befitting for observation of gravitationally lensed objects as, for lensing effects to take place, large distances are required over which more faint objects would not be able to be viewed. An indication of strong gravitational lensing is several images of the same object seen in close proximity on the sky. In order to reduce the data to more likely candidates, counterparts within a given radius are found in the second data release from Gaia; a survey in the optical with higher resolution than eROSITA. An algorithm is produced which removes most likely stellar Gaia sources using their X-ray to optical flux ratios and astrometry parameters. The Gaia sources which have no neighbours within another given radius are then also removed, leaving a catalogue of potential multiply lensed QSOs. This automated script was then applied to an eROSITA catalogue and the results compared with known lenses. The remaining sources were also checked visually using Pan-STARRS optical survey data. The results seem to be promising, although a great deal further refinement is needed through visual inspection to find the most promising candidates for lensed QSOs. / <p>Written under the joint supervision of Georg Lamer at the Leibniz Institute for Astrophysics in Potsdam. The presentation was held online at the Institute due to the COVID-19 pandemic.</p>
56

The Metallicity Structure of the Milky Way halo I : Creating a stellar catalogue of the distant halo’s red giants

Byström, Amanda January 2021 (has links)
The Milky Way's halo is an approximately spherical distribution of stars surrounding the Galaxy that carries the history of the Milky Way. The outer halo is a Galactic region with long dynamical timescales largely built up by accreted material. Probing its stellar constituents has been historically difficult due to the distances of outer halo stars, making them appear faint. To characterise the distant halo and unravel the history of our galaxy, we thus need to use stars that are intrinsically bright, i.e. giant stars. To draw useful conclusions about the distant halo, these target giants should have metallicity and kinematics information. Therefore a catalogue of distant halo giants with Pristine survey metallicities, Gaia mission data and distances has been created in this work. The cuts used to create this catalogue are made to remove as many dwarf stars as possible and have been tested on a training sample containing spectroscopic metallicities and surface gravities as well as Gaia mission data. Defining giants as being all stars with log(g) &lt; 3.5 dex, we can calculate the purity and completeness of the sample after the cuts have been applied to test which cuts optimise the catalogue. The methods used to cut away the dwarfs are to first plot all stars with positive Gaia parallaxes and fractional parallax uncertainties smaller than 50% in a colour-absolute magnitude diagram and remove all stars from the sample that in this plot populate the main sequence. We then colour-code the colour-apparent magnitude diagram by purity and completeness after this parallax cut has been performed, and select a region in this diagram in which both purity and completeness are maximised, with the final region being (GBP,0 - GRP,0) &gt; 0.8 and G0 &lt; 17.6. The distances to the stars in this region are then computed by comparing their apparent magnitudes to the absolute ones of isochrones. These cuts are then applied to a sample of 6,884,547 stars with Pristine survey and Gaia mission data. The final catalogue is kinematically unbiased and contains 345,303 halo giants. It contains 78% giants and only 4% of giants are erroneously deselected.  With the final sample we are able to probe as deep as 103 kpc into the halo and have created preliminary metallicity distribution functions of different regions of the halo. This sample will be used to further investigate the distant halo metallicity structure and its substructure that was created through merger events.
57

Kepler Planet Occurrence Rates for Mid-Type M Dwarfs as a Function of Spectral Type

Hardegree-Ullman, Kevin Karlyle January 2018 (has links)
No description available.
58

Finding new members of the VelHel-4 stream

Johansson, Lucas January 2023 (has links)
According to the paradigm of lambda-CDM cosmology, the stellar halo ofour Galaxy has been built-up over time through the accretion of other galaxiesand star clusters. The remnants of some of these are still observable today asstellar streams, but are typically very faint and difficult to resolve amidst the farmore numerous foreground Milky Way stars. The VelHel-4 stream, discoveredby Helmi et al. [2017], consists of seven members selected based on their energiesand angular momenta. Further studies of these stars has shown evidence ofglobular cluster (GC) abundance patterns, suggesting that the stream originatedfrom a GC progenitor, but a larger sample is needed to verify this signature. Theobjective of this thesis is to find new candidate members of the VelHel-4 stellarstream in order to better characterize its properties and to confirm a possibleGC origin.The preliminary selection of stars was done kinematically, by computing theorbital actions and energies using astrometric data and radial velocities for abright subset of the Gaia DR3 database, and then analyzing the clustering ofstream members in different combinations of action space. The selected samplewas then cleaned by analyzing the positions of these stars in a colour-magnitudediagram. In total, 34 stars were included in the final selection. Follow-up high-resolution spectroscopy of these candidates is needed to study their stellar abun-dances and confirm the possible GC origin of this stream.
59

Ampliando horizontes da missão espacial Gaia graças à análise de objetos extensos / Plus loin avec la mission spatiale Gaia grâce à l\'analyse des objets étendus

Martins, Alberto Garcez de Oliveira Krone 18 March 2011 (has links)
Este trabalho tem como objetivo principal verificar se é possível fazer ciência com as observações de objetos extensos que serão realizadas pela missão espacial Gaia. Um dos mais ambiciosos projetos da Astronomia moderna, essa missão observará mais de um bilhão de objetos em todo o céu com precisões inéditas, fornecendo dados astrométricos, fotométricos e espectroscópicos. Naturalmente, devido à sua prioridade astrométrica o Gaia foi optimizado para o estudo de objetos pontuais. Contudo, diversas fontes associadas a emissões extensas serão observadas. Essas emissões podem ter origem intrínseca, como galáxias, ou extrínseca, como projeções de objetos distintos na mesma linha de visada, e deverão ter soluções astrométricas aquém do ideal. Para estudar essas emissões suas imagens bidimensionais devem ser analisadas. Contudo, como o Gaia não obtém tais dados, iniciamos este trabalho verificando se a partir de suas observações unidimensionais seria possível reconstruir imagens de objetos em todo céu. Dessa forma, por um lado, nós estimamos a quantidade de casos sujeitos à presença de emissões extensas extrínsecas, apresentamos um método que desenvolvemos para segregar fontes astronômicas em imagens reconstruídas, e mostramos que sua utilização possibilitará estender o catálogo final de forma confiável em milhões de fontes pontuais, muitas das quais estarão além da magnitude limite do instrumento. Por outro lado, no caso de emissões intrínsecas, primeiro obtivemos uma es- timativa superior para o número de casos que o Gaia poderá observar. Então verificamos que após reconstruções de imagens, os códigos aqui desenvolvidos per- mitirão classificar morfologicamente milhões de galáxias nos tipos precoce/tardio e elíptico/espiral/irregular. Mostramos ainda um método que construímos para realizar a decomposição bojo/disco diretamente a partir das observações unidimensionais do Gaia de forma completamente automática. Finalmente concluímos que sim, é possível aproveitar muitos desses dados que poderiam ser ignorados para fazer ciência. E que salva-los possibilitará tanto a detecção de milhões de objetos além do limite de magnitude do Gaia, quanto estudos da morfologia de milhões de galáxias cujas estruturas podem ser apenas reveladas do espaço ou por meio de óptica adaptativa, expandindo um pouco mais os horizontes dessa já abrangente missão. / Ce travail a comme objectif principal de vérifier s\'il est possible de faire de la science avec les observations d\'objets étendus qui seront réalisées par la mission spatiale Gaia. Cette mission, l\'un des plus ambitieux projets de l\'Astronomie moderne, observera plus d\'un milliard d\'objets dans tout le ciel avec des précisions inédites, fournissant des données astrométriques, photométriques et spectroscopiques. Naturellement, en fonction de sa priorité astrométrique, Gaia a été optimisé pour l\'étude d\'objets ponctuels. Néanmoins, diverses sources associées à des émissions étendues seront observées. Ces émissions peuvent avoir une origine intrinsèque, telles que les galaxies, ou extrinsèque, telles que les projections d\'objets distincts sur la même ligne de visée, et présenteront probablement de solutions astrométriques moins bonnes. Pour étudier ces émissions, leurs images bidimensionnelles doivent être analysées. Néanmoins, comme Gaia ne produit pas de telles données, nous avons commencé ce travail en vérifiant si à partir de ses observations unidimensionnelles il serait possible de reconstruire des images 2D d\'objets dans tout le ciel. Nous avons ainsi estimé la quantité de cas sujets à la présence démissions étendues extrinsèques, et nous avons présenté une méthode que nous avons développée pour analyser leurs images reconstruites. Nous avons montré que l\'utilisation de cette méthode permettra détendre le catalogue final de façon fiable à des millions de sources ponctuelles dont beaucoup dépasseront la magnitude limite de l\'instrument. Dun autre coté, dans le cas démissions intrinsèques, nous avons premièrement obtenu une estimation supérieure du nombre de cas que Gaia pourra observer. Nous avons alors vérifié qu\'après les reconstructions d\'images, les codes que nous avons développés permettront de classifier morphologiquement des millions de galaxies dans les types précoce/tardif et elliptique/spirale/irrégulière. Nous avons de plus présenté une méthode que nous avons développée pour réaliser la décomposition bulbe/disque directement à partir des observations unidimensionnelles de Gaia de façon complètement automatique. Finalement nous avons conclu qu\'il est possible d\'utiliser beaucoup de ces données qui pourraient être ignorées pour faire de la science. Et que le fait de les exploiter permettra aussi bien la détection de millions d\'objets qui dépassent la limite de magnitude de Gaia, que de mener des études sur la morphologie de millions de galaxies dont les structures ne peuvent être révélées qu\'à partir de l\'espace ou au moyen d\'optique adaptative, augmentant un peu plus les horizons de cette mission déjà immense.
60

Sanningens väg i det sjätte massutdöendets tidsålder : Heidegger och Parmenides i naturrättens tjänst / The Way of Truth in the Age of the Sixth Mass Extinction : Heidegger and Parmenides in the Service of the Rights of Nature

Larsson, Linus January 2024 (has links)
The Rights of Nature movement is a quickly growing global phenomenon. However, it is not always obvious what the movement really means. What is its underlying experience? How can its transformative depth be formulated? What is the meaning of this depth? Starting from the ‘Universal Declaration of the Rights of Mother Earth’ this essay seeks to elucidate the ontological meaning of these questions through attending to the possible relation of the Rights of Nature movement to Heidegger’s turning toward Parmenides, in the sense of ‘primordial thinker’, or ‘essential thinker’, that is, a thinker who in an essential way thinks the origin as such. This ‘origin’ will be dealt with in relation to the oikos of ecology. In other words ‘essential thinking’ will be brought forward as a thinking that essentially makes possible the mindful awareness of this oikos, this ‘home’, ‘house’, ‘abode’, or ‘place of dwelling’. A chief point of the essay is that an essential experience of this oikos is necessary if the ontological implications of the Rights of Nature movement is to be disclosed.

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