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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.
81

Wide Field Aperture Synthesis Radio Astronomy

Bock, Douglas Carl-Johan January 1998 (has links)
This thesis is focussed on the Molonglo Observatory Synthesis Telescope (MOST), reporting on two primary areas of investigation. Firstly, it describes the recent upgrade of the MOST to perform an imaging survey of the southern sky. Secondly, it presents a MOST survey of the Vela supernova remnant and follow-up multiwavelength studies. The MOST Wide Field upgrade is the most significant instrumental upgrade of the telescope since observations began in 1981. It has made possible the nightly observation of fields with area ~5 square degrees, while retaining the operating frequency of 843 MHz and the pre-existing sensitivity to point sources and extended structure. The MOST will now be used to make a sensitive (rms approximately 1 mJy/beam) imaging survey of the sky south of declination -30&deg. This survey consists of two components: an extragalactic survey, which will begin in the south polar region, and a Galactic survey of latitudes |b| &lt 10&deg. These are expected to take about ten years. The upgrade has necessitated the installation of 352 new preamplifiers and phasing circuits which are controlled by 88 distributed microcontrollers, networked using optic fibre. The thesis documents the upgrade and describes the new systems, including associated testing, installation and commissioning. The thesis continues by presenting a new high-resolution radio continuum survey of the Vela supernova remnant (SNR), made with the MOST before the completion of the Wide Field upgrade. This remnant is the closest and one of the brightest SNRs. The contrast between the structures in the central pulsar-powered nebula and the synchrotron radiation shell allows the remnant to be identified morphologically as a member of the composite class. The data are the first of a composite remnant at spatial scales comparable with those available for the Cygnus Loop and the Crab Nebula, and make possible a comparison of radio, optical and soft X-ray emission from the resolved shell filaments. The survey covers an area of 50 square degrees at a resolution of 43&quot x 60&quot, while imaging structures on scales up to 30'. It has been used for comparison with Wide Field observations to evaluate the performance of the upgraded MOST. The central plerion of the Vela SNR (Vela X) contains a network of complex filamentary structures. The validity of the imaging of these filaments has been confirmed with Very Large Array (VLA) observations at 1.4 GHz. Unlike the situation in the Crab Nebula, the filaments are not well correlated with H-alpha emission. Within a few parsec of the Vela pulsar the emission is much more complex than previously seen: both very sharp edges and more diffuse emission are present. It has been postulated that one of the brightest filaments in Vela X is associated with the X-ray feature (called a `jet') which appears to be emanating from the region of the pulsar. However, an analysis of the MOST and VLA data shows that this radio filament has a flat spectral index similar to another more distant filament within the plerion, indicating that it is probably unrelated to the X-ray feature.
82

Wide Field Aperture Synthesis Radio Astronomy

Bock, Douglas Carl-Johan January 1998 (has links)
This thesis is focussed on the Molonglo Observatory Synthesis Telescope (MOST), reporting on two primary areas of investigation. Firstly, it describes the recent upgrade of the MOST to perform an imaging survey of the southern sky. Secondly, it presents a MOST survey of the Vela supernova remnant and follow-up multiwavelength studies. The MOST Wide Field upgrade is the most significant instrumental upgrade of the telescope since observations began in 1981. It has made possible the nightly observation of fields with area ~5 square degrees, while retaining the operating frequency of 843 MHz and the pre-existing sensitivity to point sources and extended structure. The MOST will now be used to make a sensitive (rms approximately 1 mJy/beam) imaging survey of the sky south of declination -30&deg. This survey consists of two components: an extragalactic survey, which will begin in the south polar region, and a Galactic survey of latitudes |b| &lt 10&deg. These are expected to take about ten years. The upgrade has necessitated the installation of 352 new preamplifiers and phasing circuits which are controlled by 88 distributed microcontrollers, networked using optic fibre. The thesis documents the upgrade and describes the new systems, including associated testing, installation and commissioning. The thesis continues by presenting a new high-resolution radio continuum survey of the Vela supernova remnant (SNR), made with the MOST before the completion of the Wide Field upgrade. This remnant is the closest and one of the brightest SNRs. The contrast between the structures in the central pulsar-powered nebula and the synchrotron radiation shell allows the remnant to be identified morphologically as a member of the composite class. The data are the first of a composite remnant at spatial scales comparable with those available for the Cygnus Loop and the Crab Nebula, and make possible a comparison of radio, optical and soft X-ray emission from the resolved shell filaments. The survey covers an area of 50 square degrees at a resolution of 43&quot x 60&quot, while imaging structures on scales up to 30'. It has been used for comparison with Wide Field observations to evaluate the performance of the upgraded MOST. The central plerion of the Vela SNR (Vela X) contains a network of complex filamentary structures. The validity of the imaging of these filaments has been confirmed with Very Large Array (VLA) observations at 1.4 GHz. Unlike the situation in the Crab Nebula, the filaments are not well correlated with H-alpha emission. Within a few parsec of the Vela pulsar the emission is much more complex than previously seen: both very sharp edges and more diffuse emission are present. It has been postulated that one of the brightest filaments in Vela X is associated with the X-ray feature (called a `jet') which appears to be emanating from the region of the pulsar. However, an analysis of the MOST and VLA data shows that this radio filament has a flat spectral index similar to another more distant filament within the plerion, indicating that it is probably unrelated to the X-ray feature.
83

Ανίχνευση και μελέτη εξωγαλαξιακών υπολειμμάτων υπερκαινοφανών σε πολλαπλά μήκη κύματος / Detection and study of extragalactic multi-wavelength supernova remnants

Λεωνιδάκη, Ιωάννα 28 February 2013 (has links)
Η παρούσα διατριβή παρουσιάζει τα αποτελέσματα μιας συστηματικής έρευνας των πληθυσμών Υπολειμμάτων Υπερκαινοφανών (Υ/Υ) σε έξι κοντινούς γαλαξίες (NGC 2403, NGC 3077, NGC 4214, NGC 4395, NGC 4449 και NGC 5204) βασισμένη σε αρχειακά δεδομένα του δορυφόρου ακτίνων-Χ Chandra, και σε βαθειές οπτικές παρατηρήσεις με τα στενά φίλτρα Hα (λ 6563) και [SΙΙ] (λλ 6716, 6731) καθώς και φασματοσκοπικές παρατηρήσεις. Η ταξινόμηση των Υ/Υ επιλεγμένων στις ακτίνες-Χ βασίστηκε στα μαλακά, θερμικά φάσματα (kT < 3 keV) των πηγών στις ακτίνες-Χ ή στα χρώματά τους στις ακτίνες-Χ. Αντίστοιχα, η ταξινόμηση των οπτικών Υ/Υ βασίστηκε στο καθιερωμένο κριτήριο του λόγου των γραμμών εκπομπής [SΙΙ](λλ 6716, 6731)/Hα > 0.4. Εντοπίστηκαν 37 θερμικά Υ/Υ στις ακτίνες-Χ, 30 εκ των οποίων είναι νέες ανακαλύψεις και ~400 (~350 από αυτά είναι νέες ανιχνεύσεις) φωτομετρικά Υ/Υ, για 67 από τα οποία πιστοποιήθηκε φασματοσκοπικά η φύση τους ως Υ/Υ. Πολλοί από τους γαλαξίες στο δείγμα μας μελετώνται για πρώτη φορά στις ακτίνες-Χ (NGC 4214, NGC 4395 και NGC 5204) ή στο οπτικό μέρος του φάσματος (NGC 4395, NGC 3077) με συστηματικό τρόπο, καταλήγοντας στην ανακάλυψη αρκετών νέων Υ/Υ. Σε πολλές περιπτώσεις, η ταξινόμηση των πηγών ως Υ/Υ στις ακτίνες-Χ ή στο οπτικό μέρος του φάσματος επιβεβαιώνεται από ομόλογα Υ/Υ που έχουν ανιχνευθεί σε άλλα μήκη κύματος, δείχνοντας ότι οι μέθοδοι ανίχνευσης που χρησιμοποιούμε είναι αξιόπιστες. Συζητάμε τις ιδιότητες (π.χ. φωτεινότητα, θερμοκρασία, πυκνότητα, ταχύτητα σοκ) των Υ/Υ σε διάφορους τύπους γαλαξιών και ως εκ τούτου διαφορετικά περιβάλλοντα, προκειμένου να δούμε την εξάρτησή τους από το μεοσαστρικό μέσο. Συσχετίζουμε παραμέτρους των ανιχνευμένων οπτικών Υ/Υ (λόγος [SΙΙ]/Hα, φωτεινότητα) με τις παραμέτρους των αντίστοιχων Υ/Υ στις ακτίνες-Χ (θερμοκρασία, φωτεινότητα, πυκνότητα) προκειμένου να κατανοήσουμε την εξέλιξή τους. Μερικά από τα πιο ενδιαφέροντα αποτελέσματα αυτής της έρευνας είναι τα ακόλουθα: α) Βρίσκουμε ότι τα Υ/Υ που είναι ανιχνευμένα στις ακτίνες-Χ και βρίσκονται σε άμορφους γαλαξίες φαίνεται να είναι πιο λαμπρά από εκείνα στους σπειροειδείς γαλαξίες. Αποδίδουμε αυτό το γεγονός στη χαμηλότερη μεταλλικότητα των άμορφων γαλαξιών από αυτή των σπειροειδών (η χαμηλότερη μεταλλικότητα δημιουργεί πρόγονους αστέρες μεγαλύτερης μάζας) ή στις υψηλότερες τοπικές πυκνότητες που παρατηρούνται στο μεσοαστρικό μέσο των άμορφων γαλαξιών, β) Η σύγκριση του αριθμού των παρατηρούμενων λαμπρών Υ/Υ στις ακτίνες-Χ με τον αριθμό αυτών που αναμένονται με βάση τις κατανομές φωτεινότητας των Υ/Υ στις ακτίνες-Χ στα Νέφη του Μαγγελάνου και στον M33, δείχνουν ότι κατανομές φωτεινότητας των Υ/Υ μεταξύ σπειροειδών και άμορφων γαλαξιών είναι διαφορετικές, από αυτές που αφορούν τα Υ/Υ στους άμορφους γαλαξίες και τείνουν να είναι πιο επίπεδες, γ) Βρίσκουμε ότι υπάρχει διαφορά στους λόγους [NΙΙ]/Hα των Υ/Υ μεταξύ διαφορετικών τύπων γαλαξιών, το οποίο κατά πάσα πιθανότητα οφείλεται σε διαφορές στη μεταλλικότητά τους και δ) Υπάρχουν ισχυρές ενδείξεις για μια γραμμική σχέση μεταξύ του αριθμού των λαμπρών Υ/Υ στο οπτικό και στις ακτίνες-Χ και του ρυθμού αστρογένεσης των γαλαξιών του δείγματος. / This thesis presents the results of a comprehensive investigation of the Supernova Remnant (SNR) populations in six nearby galaxies (NGC 2403, NGC 3077, NGC 4214, NGC 4395, NGC 4449 and NGC 5204) based on Chandra archival data and deep optical narrow-band Hα and [SΙΙ] images, as well as spectroscopic observations. The classification of X-ray emitting SNRs was based on their soft thermal spectra (kT < 3 keV) or their X-ray colors and for optically-emitting SNRs on the well-established emission-line flux criterion of [SΙΙ](λλ 6716, 6731)/Hα(λ 6563) > 0.4. We have identified 37 X-ray selected thermal SNRs, 30 of which are new discoveries and ~400 optical SNRs (~350 are new detections), for 67 of which we spectroscopically verified their shock-excited nature. Many of the galaxies in our sample are studied for the first time in the X-ray (NGC 4214, NGC 4395, and NGC 5204) or optical (NGC 4395, NGC 3077) band in a self-consistent way, resulting in the discovery of many new SNRs. In many cases, the X-ray and optical classifications are confirmed based on the identification of SNR counterparts in other wavelengths, giving us confidence that the detection methods we use are robust. We discuss the properties (e.g. luminosity, temperature, density, shock velocity) of the X-ray/optically detected SNRs in different types of galaxies and hence different environments, in order to address their dependence on their interstellar medium. We compare optical ([SΙΙ]/Hα ratio, luminosity) and X-ray parameters (temperature, luminosity, density) of the detected SNRs, in order to understand their evolution and investigate possible selection effects. The most intriguing results of this survey are the following: a) We find that X-ray selected SNRs in irregular galaxies appear to be more luminous than those in spirals. We attribute this either to the lower metallicities and therefore more massive progenitor stars of irregular galaxies or to the higher local densities of the interstellar medium, b) A comparison of the numbers of observed luminous X-ray selected SNRs with those expected from the luminosity functions of X-ray SNRs in the Magellanic Clouds and M33 suggest different luminosity distributions between the SNRs in spiral and irregular galaxies, with the latter tending to have flatter distributions, c) We find that there is a difference in [NΙΙ]/Hα line ratios of the SNR populations between different types of galaxies which is the result of the low metalicity of irregular galaxies, and d) We find evidence for a linear relation between the number of luminous optical or X-ray SNRs and Star Formation Rate in our sample of galaxies.
84

Análise espacial da fragmentação florestal em áreas do bioma mata atlântica utilizando linguagem R / Spatial analysis of forest fragmentation in areas of the atlantic forest biome using R language

Marchesan, Juliana 23 February 2017 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / There are decades the deforestation resulting from the process of anthropization of the landscape has been causing the destruction of natural resources. The native forests are giving space mainly for agriculture, cattle raising and urbanization, occurring the formation of fragments. In this context, the present study aims to develop an R language package for the calculation of landscape ecology metrics, as well as, to use the same for the analysis of the forest fragments, under the domain of the Atlantic Forest biome, located in the hydrographic sub-basin of Arroio Jaquirana, Rio Grande do Sul, for the year 2016. For the development of the package, called LanscapeMetrics, used the R software and packages igraph, raster, rgdal, rgeos, devtools, roxygen2 and Rtools. In order to avoid the use of redundant metrics a total of twenty-one was selected covering metrics of area and density, shape, border, central area and proximity. For the mapping of the forest fragments, used images of the RapidEye/REIS satellite dated 02/29/2016, with the definition of two classes of land use and cover: native forest and other uses. The classification was supervised through the Bhattacharyya algorithm, using SPRING software. The fragments were analyzed separately in size classes, to separate them used the software R. The results showed that the native forest occupied 14,099.89 ha, corresponding to 34.01% of the study area, covering a total of 1,995 fragments, of which 93.43% less than 5 ha. In the size class occupied by the fragments smaller than 5 ha, it was found a higher edge value and a perimeter-area ratio, indicating a greater edge effect, so that the central areas of these remnants are exposed to the effects of the external matrix. This fact is proved by the calculation of the metrics of central areas, since, subject to the edge distances from 80 m, total domination by the edge effect occurs. However, these smaller fragments are important, since they lessen the distance between the larger fragments, due to their high density and being well distributed in the study area. Thus, it is concluded that R is a promising and efficient tool for spatial data analysis, which allowed the manipulation of data from remote sensors. / Há décadas os desmatamentos decorrentes do processo de antropização da paisagem vêm ocasionando a destruição dos recursos naturais. As florestas nativas foram cedendo espaço principalmente para agricultura, pecuária e urbanização, ocorrendo a formação de fragmentos. Desse modo, o presente estudo tem por objetivo desenvolver um pacote em linguagem R para cálculo de métricas de ecologia da paisagem, bem como, utilizar o mesmo para análise dos fragmentos florestais, sob domínio do bioma Mata Atlântica, localizados na sub-bacia hidrográfica do Arroio Jaquirana, Rio Grande do Sul, para o ano de 2016. Para o desenvolvimento do pacote, denominado LanscapeMetrics, utilizou-se o programa R e os pacotes igraph, raster, rgdal, rgeos, devtools, roxygen2 e Rtools. De modo a evitar a utilização de métricas redundantes foram selecionadas um total de vinte e uma, abrangendo métricas de área e densidade, forma, borda, área central e de proximidade. Para o mapeamento dos fragmentos florestais utilizou-se imagens do satélite RapidEye/REIS datadas de 29/02/2016, com a definição de duas classes de uso e cobertura da terra: floresta nativa e outros usos. A classificação foi de forma supervisionada por meio do algoritmo Bhattacharyya, utilizando o programa SPRING. Os fragmentos foram analisados separadamente em classes de tamanho, para separá-los utilizou-se o programa R. Os resultados demonstraram que a floresta nativa ocupou 14.099,89 ha, correspondendo a 34,01% da área de estudo, abrangendo um total de 1.995 fragmentos, destes, 93,43% inferiores à 5 ha. Na classe de tamanho ocupada pelos fragmentos menores que 5 ha, encontrou-se maior valor de borda e de razão perímetro-área, indicando maior efeito de borda, dessa forma, as áreas centrais destes remanescentes estão expostas aos efeitos da matriz externa. Este fato é comprovado pelo cálculo das métricas de áreas centrais, uma vez que, submetidos às distâncias de borda a partir de 80 m, ocorre total dominação pelo efeito de borda. Contudo, estes fragmentos menores são importantes, uma vez que amenizam a distância entre os fragmentos maiores, devido sua alta densidade e por estarem bem distribuídos na área de estudo. Desse modo, conclui-se que o R é uma ferramenta promissora e eficiente para análise de dados espaciais, o qual permitiu a manipulação de dados provenientes de sensores remotos.
85

Les ruines de guerre et la nation française (1914-1921) / Ruins of War and the French Nation (1914-1921)

Danchin, Emmanuelle 17 December 2012 (has links)
Ce travail de thèse porte sur les destructions matérielles de la Grande Guerre et plus particulièrement sur la manière dont la société française s’est emparée des représentations de ruines pour en faire un symbole de douleur. Première conséquence directe et visible d’un conflit, les ruines témoignent de la guerre, de sa conduite, mais aussi des souffrances vécues par les militaires et les populations civiles. De l’artiste officiel rattaché aux armées au simple citoyen non mobilisé, en passant par le soldat anonyme, tous ont évoqué pendant la Première Guerre mondiale les destructions matérielles, les paysages désolés, la terre bouleversée par l’artillerie. Photographiées, dessinées, filmées, exposées à Paris, Londres ou Genève, les représentations de ruines se sont ainsi affichées dans les journaux, ont circulé sous forme de cartes postales et ont été reproduites dans divers ouvrages. Ces représentations iconographiques ont été instrumentalisées dès le commencement du conflit pour appuyer des discours contribuant à mobiliser les populations et à convaincre les pays neutres du bien-fondé de la guerre. Elles sont ensuite devenues une manière de rendre visible le conflit, mais surtout de témoigner de la violence nouvelle de cette guerre d’artillerie. Les descriptions littéraires en firent des corps vivants, blessés, transpositions anthropomorphes des soldats dont on montrait peu les corps. Cibles de la violence des armes, corps symboliques, fragiles, elles incarnèrent donc successivement le corps du combattant, puis le corps sacré de la Nation. La paix revenue, les ruines furent mobilisées une dernière fois pour appuyer les demandes de réparations de guerre. Elles furent aussi honorées par des remises de décorations et valorisées dans les circuits touristiques. Le débat autour des ruines se réduisit alors à un questionnement sur la conservation des vestiges de guerre. / This PhD work focuses on the material destruction caused by the Great War and more specifically on the way French society used the representations of ruins as a symbol of pain. As a first direct and visible consequence of conflict, ruins bear testimony to it, to its course, but also to the suffering of soldiers and civilian populations. Everybody, from the official military artist, the anonymous soldier to the ordinary citizen, evoked the material destruction, the desolate landscapes and the earth upheaved by artillery shells during the First World War. Photographed, drawn, filmed, exhibited in Paris, London or Geneva, the representations of ruins were shown in newspapers, they have been distributed as postcards and have also been reproduced in various works. These iconographic representations were used from the very beginning of the conflict to support the arguments used to mobilize populations and convince neutral countries of the validity of the war. They then became a way of making the conflict visible, but especially to testify the new violence caused by artillery. The Literary descriptions presented them as living, wounded bodies, as anthropomorphic transpositions of the soldiers whose bodies were rarely displayed. Targets of armed violence, symbolic bodies and fragile, ruins have embodied first of all the body of the warrior and subsequently the sacred body of the Nation. Once peace had been restored, the ruins were mobilized one last time to reinforce the demands for war reparations. They were also honoured through decorative ceremonies and valued through organized tourist tours. Since then the debate around ruins has been minimized to a question of their conservation as remnants of war.
86

Análise das variáveis tempo e distância no método “pontos de contagem” no estudo da assembleia de aves na estação ecológica de Caetetus (EECa), São Paulo

Gerotti, Raphael Whitacker January 2017 (has links)
Orientador: Reginaldo José Donatelli / Resumo: Pontos de contagem é um método atrativo para utilização em programas de monitoramento de aves por ser simples e permitir que vários locais sejam amostrados. Contudo, nos estudos realizados em regiões tropicais utilizando-se deste método, os autores utilizam a variável "tempo" de forma diferente para registrar a abundância das aves nos fragmentos florestais. Portanto, os dados obtidos por estes diferentes estudos não podem ser comparados entre si, pois o tempo gasto nos pontos e o tempo total das contagens diferem significativamente, assim como as distâncias percorridas. Desta forma, o objetivo do presente trabalho foi o de comparar quatro durações de tempos distintas (5, 10, 15 e 20 minutos) para identificar qual destas registra maior riqueza e abundância de aves em fragmentos de florestas tropicais. As amostragens foram realizadas durante 12 meses em um fragmento de floresta estacional semidecidual de 2.180 ha no interior de São Paulo. Um total de 120 minutos de amostragem foi realizado a cada mês para cada tempo distinto, o que exigiu um número diferente de pontos amostrais e uma diferente distância total percorrida na floresta. Com relação à riqueza e abundância, os testes estatísticos evidenciaram que o tempo de cinco minutos apresentou resultados que diferem significativamente dos outros tempos (10’, 15’ e 20’). Além disso, houve uma correlação positiva entre as diferentes distâncias percorridas e a abundância registrada, ou seja, quanto maior a distância percorrida, mai... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Point counts are attractive for use in avian monitoring programs because they are straightforward and allow numerous geographic sites to be sampled. However, in studies conducted with the point count method in tropical regions, authors use the variable "time" differently to record the abundance of birds in forest remnants. Therefore, the data obtained by different studies cannot be compared since the time spent at the points and the total counting time differ significantly, as do the distances traveled. The objective of the present study was to compare four distinct point count times (5, 10, 15 and 20 minutes) to identify which registers relatively greater bird richness and abundance in tropical forest fragments. Samplings were carried out for 12 months in a 2,180 ha fragment of semideciduous forest in the interior of the state of São Paulo. A total of 120 minutes of sampling was carried out each month for each counting time, which required a different number of counting points and a different total distance traveled in the forest. With respect to richness and abundance, the statistical tests showed that five minutes of counting yielded results that were significantly different from those of the other point count times. Additionally, there was a positive correlation between the different distances traveled and the recorded abundance, i.e., the greater the distance traveled, the greater the richness and abundance. One aspect of community ecology that must be considered is that... (Complete abstract click electronic access below) / Mestre
87

Diversidade e estrutura de taxocenoses de anfíbios anuros em uma paisagem fragmentada no centro-oeste paulista

Brassaloti, Ricardo Augusto [UNESP] 18 October 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-10-18Bitstream added on 2014-06-13T19:28:31Z : No. of bitstreams: 1 brassaloti_ra_me_sjrp.pdf: 1192726 bytes, checksum: 889d596d80308ab95ffaadb3f0640f10 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Anfíbios anuros são particularmente sensíveis a alterações no habitat, seja pela sua baixa vagilidade e fidelidade a áreas de reprodução e forrageio, ou mesmo, por possuírem ciclo de vida complexo com fase aquática e terrestre. Tais características os tornam bons modelos para o estudo de questões relacionadas à modificação no habitat, sejam elas relativas a identificação de padrões ou inferência sobre processos associados à fragmentação ou perda de habitat original ou mesmo ocupação e colonização em áreas alteradas. Dentro deste contexto, este trabalho procurou como objetivo principal, determinar a diversidade e estrutura da taxocenose de anfíbios anuros presente em remanescentes de floresta estacional semidecidual (FES) e compará-la com a registrada em implantações silviculturais, na região centro-oeste do estado de São Paulo (capítulo 3). Além deste, buscou-se o levantamento da fauna em uma área preservada (Unidade de Conservação), afim de aproximar-se da composição presente na região antes do processo de fragmentação (capítulo 1), além da distribuição espacial das espécies encontradas nesse tipo de formação florestal (FES) e sua possível relação biogeográfica com taxocenoses presentes nas fitofisionomias limítrofes a ela (capítulo 2). A partir do levantamento mensal das espécies em campo durante nove meses consecutivos, compreendidos na estação de maior atividade para o grupo, e utilizando-se de metodologias diferentes e complementares (armadilhas de interceptação e queda e procura em ambientes de reprodução), foram determinadas a abundância e a riqueza de anuros em três áreas comparáveis de implantação florestal (silvicultura de eucalipto) e três remanescentes florestais (fragmentos de FES), além da única grande unidade de conservação em um raio de 150 km... / Frogs are particularly sensitive to changes in habitat, either by their low vagility and fidelity to breeding and foraging sites, or even by had a complex life cycle with aquatic and terrestrial phase. Such characteristics make them good models for studying issues related to habitat change, whether concerning the identification of patterns or inferences about processes associated with fragmentation and habitat loss or occupancy and colonization in disturbed areas. Within this context, this work main goal sought to determine the diversity and structure of his assemblage of amphibians in forest remnants semideciduous (FES) and compare it with that recorded in silvicultural deployments in the mid-west region of São Paulo (Chapter 3). Besides this, we sought to survey anurans in a protected area (Conservation Unit), in order to approach the species composition in this region, before the fragmentation process (Chapter 1), and we tried to elucidate the spatial distribution of the species found in this type of forest formation (FES) and its possible biogeographical relationship with assemblages present in adjacent types of vegetation (Chapter 2). From the monthly survey of the species in the field for nine months consecutively, including the season of greatest activity for the group, and using different and complementary methodologies (pitfall traps and survey at breeding sites) were determined the abundance and richness of frogs in three comparable areas of deployment forestry (eucalyptus forestry) and three remaining forest (remnants of FES), and the only major conservation unit within a radius of 150 km. For comparison of data abundance and diversity, between forestry and forest remnants, were used univariate analysis of variance (ANOVA) with each data sets, and also descriptive techniques such as non-metric multidimentional scaling (NMDS), clustering (UPGMA) and similarity analysis... (Complete abstract click electronic access below)
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Catálogo de intensidades de linhas de emissão de remanescentes de supernovas e aplicações

Pauletti, Diogo 30 June 2011 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Emission line intensities from ionized nebulae are an important information source about this objects. There are many data on line intensities emitted from supernova remnants scattered in the literature. However, these data can be more efficiently used if avaliable in the form of an electronic data base. Based on this, it was made a catalog of emission line intensities of supernova remnants with data obtained from the literature, including lines in the spectral range of 900Å to 100 mm. About 300 supernova remnants and more than 25 000 emission line intensities were cataloged, including adittional information associated to the objects and the observations. As a demonstration of the aplicability of this catalog, diagnostic diagrams were made with emission line intensities from supernova remnants and from HII regions, using the line ratios [O III] l5007/Hb, [N II] l6583/Ha, [O II] l3727/Hb, [S II] (l6716+l6730)/Ha and [O I] l6300/Ha. Besides these traditional diagrams, the large amount of data in the catalog allowed the construction of others diagrams using relatively weak lines, rarely measured. The diagrams were effective for the classification and discrimination of these classes of objects. It was also verified the values of the ratios [O III] l5007/l4959 and [N II] l6584/l6548, which returned results in agreement with some others published. Moreover, considering the ultraviolet spectroscopy advances in recent decades, it is presented an history of the instrumentation and its performance evolution, regarding some topics that show the importance of the studies about the ultraviolet spectra of supernova remnants. Finally, a list of all ultraviolet emission lines already measured in supernova remnants until 2010 was made, and compared with a similar list created in 1996. It was found that many new lines were detected and some multiplets became resolved since then. Each one of the 142 lines was identified by its wavelength, the ion and parameters of the transition that generates it. This table may be used as a reference for identifying emission lines in supernova remnants in future studies. / As intensidades de linhas de emissão de nebulosas ionizadas constituem uma importante fonte de informação sobre esses objetos. São numerosos os dados que podem ser encontrados em diferentes artigos da literatura referentes a intensidades de linhas emitidas por remanescentes de supernovas. Porém, esses dados podem ser mais eficientemente utilizados se disponibilizados em conjunto e de maneira organizada, ou seja, na forma de um catálogo. Com base nisso, foi construído um catálogo de intensidades de linhas de emissão de remanescentes de supernovas com dados extraídos da literatura, incluindo linhas no intervalo espectral de 900 Å até 100 mm. Cerca de 300 remanescentes de supernovas e mais de 25 000 intensidades de linhas de emissão foram catalogadas, incluindo informações adicionais associadas ao objeto e à observação. Como demonstração de aplicação do catálogo, foram construídos diagramas de diagnóstico com intensidades de linhas de emissão de remanescentes de supernovas e de regiões HII, utilizando as razões de intensidades de linhas [O III] l5007/Hb, [N II] l6583/Ha, [O II] l3727/Hb, [S II] (l6716+l6730)/Ha e [O I] l6300/Ha. Além desses diagramas tradicionais, a grande quantidade de dados do catálogo permitiu construir novos diagramas utilizando linhas relativamente fracas, raramente medidas. Os diagramas mostraram-se eficientes para a classificação e distinção dessas classes de objetos. Também verificou-se os valores das razões [O III] l5007/l4959 e [N II] l6584/l6548, retornando valores em concordância com outros publicados. Por fim, considerando os avanços na espectroscopia ultravioleta das últimas décadas, apresenta-se um histórico da instrumentação utilizada e da evolução de sua performance, considerando também alguns tópicos que mostram a importância dos estudos espectroscópicos na faixa do ultravioleta em remanescentes de supernovas. Construiu-se uma lista com todas as linhas de emissão do ultravioleta já medidas em remanescentes de supernovas até o ano de 2010, fazendo-se um comparativo com as linhas medidas até o ano de 1996. Verificouse que várias novas linhas foram detectadas e que alguns multipletos passaram a ser resolvidos. Essas 142 linhas são identificadas pelo seu comprimento de onda, pelo íon e por parâmetros das transições que as geram, e são listados os remanescentes de supernovas em que cada linha foi medida. Essa tabela pode ser utilizada como referência na identificação das linhas em futuros estudos de remanescentes de supernovas.
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Análise das variáveis tempo e distância no método “pontos de contagem” no estudo da assembleia de aves na estação ecológica de Caetetus (EECa), São Paulo / Analysis of time and distance used in the "point counts" method to study bird assembly at estação ecologica de Caetetus (EECa), São Paulo

Gerotti, Raphael Whitacker [UNESP] 26 July 2017 (has links)
Submitted by Raphael Whitacker Gerotti null (raphovisky@hotmail.com) on 2017-08-23T13:48:45Z No. of bitstreams: 1 Dissertação Raphael W. - FIM 23.08.2017.pdf: 1154964 bytes, checksum: bbbd1d8b08a0c57ea8f840af0890760b (MD5) / Approved for entry into archive by Monique Sasaki (sayumi_sasaki@hotmail.com) on 2017-08-23T17:30:04Z (GMT) No. of bitstreams: 1 gerotti_rw_me_bot.pdf: 1154964 bytes, checksum: bbbd1d8b08a0c57ea8f840af0890760b (MD5) / Made available in DSpace on 2017-08-23T17:30:04Z (GMT). No. of bitstreams: 1 gerotti_rw_me_bot.pdf: 1154964 bytes, checksum: bbbd1d8b08a0c57ea8f840af0890760b (MD5) Previous issue date: 2017-07-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Pontos de contagem é um método atrativo para utilização em programas de monitoramento de aves por ser simples e permitir que vários locais sejam amostrados. Contudo, nos estudos realizados em regiões tropicais utilizando-se deste método, os autores utilizam a variável "tempo" de forma diferente para registrar a abundância das aves nos fragmentos florestais. Portanto, os dados obtidos por estes diferentes estudos não podem ser comparados entre si, pois o tempo gasto nos pontos e o tempo total das contagens diferem significativamente, assim como as distâncias percorridas. Desta forma, o objetivo do presente trabalho foi o de comparar quatro durações de tempos distintas (5, 10, 15 e 20 minutos) para identificar qual destas registra maior riqueza e abundância de aves em fragmentos de florestas tropicais. As amostragens foram realizadas durante 12 meses em um fragmento de floresta estacional semidecidual de 2.180 ha no interior de São Paulo. Um total de 120 minutos de amostragem foi realizado a cada mês para cada tempo distinto, o que exigiu um número diferente de pontos amostrais e uma diferente distância total percorrida na floresta. Com relação à riqueza e abundância, os testes estatísticos evidenciaram que o tempo de cinco minutos apresentou resultados que diferem significativamente dos outros tempos (10’, 15’ e 20’). Além disso, houve uma correlação positiva entre as diferentes distâncias percorridas e a abundância registrada, ou seja, quanto maior a distância percorrida, maior a riqueza e abundância registradas. Um aspecto da ecologia da comunidade que deve ser levado em consideração é que as espécies são distribuídas de forma heterogênea em uma floresta, pois diferentes espécies de plantas e diferentes padrões na fisionomia da floresta proporcionam diferentes tipos de micro-hábitats para aves. Quando se utiliza um maior número de pontos de amostragem, espera-se encontrar uma maior heterogeneidade da floresta, portanto, a maior riqueza registrada pela contagem de cinco minutos está associada a um maior número de pontos necessários para isolar a variável tempo. Outro fator importante é a variação encontrada nos valores do Índice Pontual de Abundância amostrados. A menor variação e consequente maior poder estatístico ocorreu na contagem mais curta (5’ minutos), indicando que o tempo é o mais eficiente para atingir os objetivos propostos. É importante ressaltar que este período de tempo exigiu quatro meses a menos para registrar o mesmo número de espécies que as outras contagens. No oitavo mês de amostragem, o tempo de cinco minutos já acumulava 119 espécies, valor maior que a riqueza total obtida com os outros tempos. Portanto, ao utilizar o método de pontos de contagem para analisar a estrutura da comunidade de aves em fragmentos florestais, o melhor resultado foi alcançado com a contagem de cinco minutos. Este tempo provou ser mais eficiente por detectar maior riqueza e abundância com menor esforço amostral, além de aumentar a chance de se registrar novas espécies devido ao maior número de pontos realizados em um maior número de micro-hábitats na floresta. / Point counts are attractive for use in avian monitoring programs because they are straightforward and allow numerous geographic sites to be sampled. However, in studies conducted with the point count method in tropical regions, authors use the variable "time" differently to record the abundance of birds in forest remnants. Therefore, the data obtained by different studies cannot be compared since the time spent at the points and the total counting time differ significantly, as do the distances traveled. The objective of the present study was to compare four distinct point count times (5, 10, 15 and 20 minutes) to identify which registers relatively greater bird richness and abundance in tropical forest fragments. Samplings were carried out for 12 months in a 2,180 ha fragment of semideciduous forest in the interior of the state of São Paulo. A total of 120 minutes of sampling was carried out each month for each counting time, which required a different number of counting points and a different total distance traveled in the forest. With respect to richness and abundance, the statistical tests showed that five minutes of counting yielded results that were significantly different from those of the other point count times. Additionally, there was a positive correlation between the different distances traveled and the recorded abundance, i.e., the greater the distance traveled, the greater the richness and abundance. One aspect of community ecology that must be considered is that species are distributed heterogeneously in a continuous forest because different plant species and different patterns in the terrain of the forest provide different microhabitats for birds. When a greater number of sampling points is used, greater forest heterogeneity is expected; therefore, the greater richness recorded by the five-minute counts is associated with a greater number of points needed to isolate the time variable. Another important factor is the variation in the sampling rates; the lowest variation, and consequently greater statistical power, occurred in the shortest count (5′), indicating that this counting time is effective for meeting the proposed objectives. Importantly, this counting time required four fewer months to record the same number of species as the other times. By the eighth month of sampling, the five-minute count had accumulated 119 species, which was higher than the total richness obtained with the other times. Therefore, when using the point method to analyze the community structure of birds in forest fragments, the best result was achieved with the five-minute count. This time proved to be more efficient because it detected greater richness and abundance with a lower sampling effort and increased the chance of registering new species due to the higher number of sampling points over a larger number of microhabitats in the forest.
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JUSTIÇA, AMBIENTE E ETNICIDADE: O controle judicial das licenças ambientais lesivas a grupos étnicos / JUSTICE, ENVIRONMENTAL AND ETHNICITY: The judicial control of environmental permits detrimental to ethnic groups

Soares, Alexandre Silva 06 April 2015 (has links)
Made available in DSpace on 2016-08-18T12:54:32Z (GMT). No. of bitstreams: 1 DISSERTACAO_ALEXANDRE SILVA SOARES.pdf: 649052 bytes, checksum: b76d2d8d4e00cf860d5021ce179c26fa (MD5) Previous issue date: 2015-04-06 / The dissertation investigates the criteria used by the judiciary for the trial of disputes concerning the environmental licensing of projects identified as harmful to ethnic groups, especially indigenous and quilombo communities. By adopting as theoretical works of François Ost, Michel Foucault and Pierre Bourdieu, we proceeded to initially examine the construction of the legal discourse on the environment, from the examination of the legal and constitutional order; then proceeded to the examination of the theme of ethnic identities in the Constitution, as well as its relationship with the protection of the environment, specifically analyzing the environmental licensing instrument, about the administrative actions of control of natural resources, along with the legalization public policies on the environment. We conducted case studies of three projects (HPPs Belo Monte, Teles Pires and the transposition of the river São Francisco) from the jurisprudence of the Supreme Court brasilian, proposing to reflect on the decision criteria effectively adopted. / A dissertação investiga os critérios utilizados pelo Poder Judiciário para o julgamento dos conflitos relativos ao licenciamento ambiental de empreendimentos apontados como lesivos a grupos étnicos, especialmente indígenas e remanescentes de comunidades de quilombos. Ao adotar como referenciais teóricos as obras de François Ost, Michel Foucault e Pierre Bourdieu, procedeu-se inicialmente à análise da construção do discurso jurídico sobre o meio ambiente, a partir do exame do ordenamento jurídico-constitucional; em seguida, procedeu-se ao exame do tema das identidades étnicas na Constituição de 1988, bem como sua relação com a proteção ao ambiente, especificamente analisando o instrumento do licenciamento ambiental, quanto à atuação administrativa de controle dos recursos naturais, ao lado da judicialização de políticas públicas em matéria de meio ambiente. Realizouse o estudo de casos de três empreendimentos (UHEs Belo Monte, Teles Pires e a Transposição do rio São Francisco) a partir da jurisprudência do Supremo Tribunal Federal, propondo-se a reflexão sobre os critérios decisórios efetivamente adotados.

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