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Search for TeV neutrinos from point-like sources in the southern sky using four years of IceCube dataAltmann, Simon David 28 February 2017 (has links)
Galaktische und extra-galaktische Objekte sind in der Lage geladene Teilchen (die kosmische Strahlung) zu sehr hohen Energien zu beschleunigen. Allerdings sind noch viele Fragen bezüglich dieser Objekte und der Beschleunigungsmechanismen offen. Sowohl Gammastrahlung als auch Neutrinos werden von den Quellen kosmischer Strahlung erwartet. Ihr Nachweis ermöglicht die Studie dieser kosmischen Teilchenbeschleuniger. Gammastrahlung wurde von galaktischen und extra-galaktischen Objekten beobachtet. Für viele dieser Objekte ist es jedoch nicht eindeutig ob diese Gammastrahlung ein Resultat der Beschleunigung kosmischer Strahlen ist. Für Neutrinos besteht diese Zweideutigkeit nicht, sie sind eindeutige Spuren der Beschleunigung kosmischer Strahlen. Der Südhimmel beheimatet viele galaktische Objekte von denen Gammastrahlung im GeV und TeV Bereich beobachtet wird. Die Detektion von Neutrinos wäre ein Beweis für die Beschleunigung kosmischer Strahlung. Der Nachweis dieser Neutrinos mit IceCube wird durch den großen Untergrund von atmosphärischen Myonen erschwert. Die hier verwendete Analyse ist auf die Selektion von Myonspuren aus Wechselwirkungen von Myonneutrinos im Detektorvolumen spezialisiert. Energieverlust und Richtung der resultierenden Myonspur wird rekonstruiert. Diese Informationen werden verwendet um nach potentiellen Quellen astrophysikalischer Neutrino im Rahmen einer ungebinnten Likelihoodanalyse zu suchen. Daten die zwischen 2011 und 2015 mit IceCube genommen wurden werden für diese Analyse verwendet. Der Fokus liegt auf Neutrinos mit Energien zwischen ein paar TeV und 100 TeV. In diesem Energiebereich wird die Sensitivität für die Detektion einer Neutrinopunktquelle um einen Faktor zwei (oder besser) verbessert. Die Resultate für eine Liste von 96 Quellkandidaten und für eine offene Suche am gesamten Südhimmel werden präsentiert. Es wurde keine signifikante Abweichung von der Untergrundhypothese gefunden. Daraus resultieren Limitationen für Neutrinoemissionen. / There are accelerators in the universe that can accelerate charged particles (cosmic rays) to very high energies. Many questions regarding these accelerators are still open. Gamma rays and neutrinos are particles expected from sites of cosmic ray acceleration and can be used to study the environment and acceleration mechanisms of these sites. While sources for both galactic and extra-galactic gamma rays have been observed, it is often unclear whether these gamma rays are by-products of cosmic ray acceleration. This ambiguity does not exist for neutrinos. An astrophysical neutrino flux has been measured by the IceCube detector. Single sources have not been resolved yet. The part of the sky visible from the southern hemisphere hosts many galactic sources observed in GeV and TeV gamma-rays. Detection of neutrinos from these sources would identify them as acceleration sites and lead to a better understanding of the environment of the acceleration sites and the acceleration mechanisms. However, this is difficult due to the vast background of atmospheric muons also detected in the IceCube detector. For this thesis, a data selection was developed that reduces this background by using parts of the detector as veto. This selection focuses on the selection of muon-tracks from muon-neutrino interactions inside the detector volume. The direction and the energy-profile of these tracks can be reconstructed. This information is used to search for potential sources using an unbinned likelihood method. This analysis uses data taken between 2011 and 2015. In contrast to earlier IceCube analyses this analysis is optimized for energies between a few TeV and 100 TeV and improves the sensitivity of the detector for a point-like source by factor of two (or better) in this energy range. Results for a list of 96 sources observed in TeV gamma-rays and a sky-scan are presented. No significant overfluctuation has been observed and limits on the neutrino emission of the sources are given.
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Phylogéographie de deux reptiles iraniens (le complexe Montivipera raddei et Ophisops elegans) et implication pour la conservation / Phylogeography of two Iranian reptiles (Montivipera raddei complex and Ophisops elegans) and implication for conservationBehrooz, Roozbeh 13 January 2017 (has links)
Les espèces de haute altitude (Sky-Islands) sont parmi les taxons les plus sensibles aux changements environnementaux et une meilleure connaissance de ces espèces (répartition, groupes génétiques, histoire d’évolution, etc.) est indispensable afin de définir les unités adaptées pour la conservation. Cette thèse a porté sur l’analyse moléculaire de deux gènes mitochondriaux (Cyt b et ND4) chez le groupe d’espèces Montivipera raddei et un gène mitochondrial (COI) chez l’Ophisops elegans dans les montagnes d’Iran qui sont des centres d’endémisme importants pour les reptiles. En me basant sur les données génétiques, je propose de considérer toutes les montivipère d’Iran comme une seule espèce ; Montivipera raddei comprenant trois sous-espèces ; Montivipera raddei albicornuta (nord du Zagros, Zanjan et nord-ouest de l’Iran jusqu’en Turquie), Montivipera raddei latifii (Alborz), et Montivipera raddei kuhrangica (centre du Zagros). Les temps de divergences obtenus entre les clades de montivipères semblent montrer des changements de la connectivité des populations pendant le Pléistocène qui résulte de l’effet fort des oscillations climatiques durant cette époque, notamment pendant les interglaciaires. Ce travail a aussi révélé une grande diversité génétique au sein des clades iraniens d’ophisops élégant ce qui pose la question de l’existence d’espèces/sous-espèces cryptiques en Iran. Finalement, ce travail a permis de définir des ESU pour les montivipères et l’ophisops élégant et notamment je propose que toutes les populations isolées du groupe d’espèces M. raddei et d’O. elegans montrant des haplotypes propres soient considérées comme des ESU pour la conservation. / High-altitude species (Sky-Islands) are among the most sensitive taxa to environmental changes and a better knowledge of these species (distribution, genetic groups, evolutionary history, etc.) is essential in order to define the adapted units for the conversation. This thesis focused on the molecular analysis of two mitochondrial genes (Cyt b and ND4) in the Montivipera raddei (Radde's Rock Viper) species group and a mitochondrial gene (COI) in Ophisops elegans (Snake-Eyed Lizard) in the mountains of Iran, which are important centers of endemism for reptiles. Based on the genetic data, I propose to consider all the Iranian montivipers as one species; Montivipera raddei comprising three subspecies; Montivipera raddei albicornuta (north of Zagros, Zanjan and northwestern Iran to Turkey), Montivipera raddei latifii (Alborz), and Montivipera raddei kuhrangica (central Zagros). The times of divergence between the clades of montivipers seem to show changes in the connectivity of populations during the Pleistocene, which results from the strong, effect of climatic oscillations during this period, especially during interglacial periods. This work also revealed a great genetic diversity within the Iranian clades of snake-eyed lizard, which raises the question of the existence of cryptic species / subspecies in Iran. Finally, this work made it possible to define ESUs for montivipers and snake-eyed lizards. In particular, I propose that all isolated populations of the M. raddei species group and O. elegans showing specific haplotypes to be considered as ESUs for conservation.
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Υλοποίηση της βαθμίδας middleware σε wireless sensor networks με έμφαση στον ασύρματο προγραμματισμό των motes / Implementation of middleware layer in wireless sensor networks laying emphasis on wireless programming of motesΒασιλόπουλος, Βασίλειος 08 July 2011 (has links)
Τα ασύρματα δίκτυα αισθητήρων αποτελούν μία πρωτοποριακή τεχνολογία που ήρθε στο προσκήνιο πριν από μία περίπου δεκαετία. Η καινοτομία της τεχνολογίας αυτής έγκειται στη συνεργασία μεγάλου αριθμού κόμβων περιορισμένων πόρων χαμηλής κατανάλωσης ισχύος σε μία μόνο εφαρμογή. Η εργασία αυτή ασχολείται με θέματα ενδιάμεσου λογισμικού σε ασύρματα δίκτυα αισθητήρων. Συγκεκριμένα, μελετάται το πρωτόκολλο Deluge που αποτελεί τη βασική επιλογή για ασύρματο προγραμματισμό δικτύων αισθητήρων που «τρέχουν» το λειτουργικό σύστημα πραγματικού χρόνου TinyOS. Παρέχοντας έναν αξιόπιστο και αποδοτικό μηχανισμό διάδοσης δεδομένων μέσω της δυαδικής εικόνας του κώδικα, το Deluge κατέχει ρόλο-κλειδί στη βαθμίδα ενδιάμεσου λογισμικού των ασύρματων δικτύων αισθητήρων. Η μελέτη και κατανόηση του πρωτοκόλλου αυτού επέτρεψε την υλοποίηση σε nesC ενός απλούστερου πρωτοκόλλου που αξιοποιεί τα βασικά χαρακτηριστικά του μηχανισμού μετάδοσης δεδομένων του Deluge. Σε συνέχεια αυτής της υλοποίησης, αξιολογήθηκε εκ νέου η διαδικασία μετάδοσης πραγματοποιώντας δοκιμές τόσο σε πραγματικές τοπολογίες κόμβων αισθητήρων (motes) που υποστηρίζουν το πρότυπο ασύρματης επικοινωνίας IEEE 802.15.4 όσο και σε περιβάλλον προσομοίωσης (TOSSIM). Τα προκύπτοντα αποτελέσματα επιβεβαιώνουν την αποδοτική μετάδοση δεδομένων σε δίκτυα αισθητήρων αξιοποιώντας το πρωτόκολλο Deluge.
Η παρούσα εργασία αποτελείται από έξι κεφάλαια. Το πρώτο κεφάλαιο παρέχει πληροφορίες για το γνωστικό αντικείμενο της εργασίας. Στο δεύτερο κεφάλαιο παρουσιάζεται μία μελέτη στην ερευνητική περιοχή των ασύρματων δικτύων αισθητήρων και στο τρίτο κεφάλαιο εξετάζονται τα βασικά χαρακτηριστικά ενός κόμβου αισθητήρων που υποστηρίζει το πρότυπο IEEE 802.15.4. Στο τέταρτο κεφάλαιο παρουσιάζεται η έννοια του ασύρματου προγραμματισμού στα δίκτυα αισθητήρων και μελετάται εκτενώς το πρωτόκολλο Deluge. Στο πέμπτο κεφάλαιο περιγράφεται η υλοποίηση που έλαβε χώρα και η αξιολόγηση αυτής με τους μηχανισμούς που αναφέρθηκαν παραπάνω. Τέλος, στο έκτο κεφάλαιο παρατίθενται τα συμπεράσματα που εξήχθησαν από την εκπόνηση της εν λόγω εργασίας και δίνονται ορισμένες κατευθύνσεις για μελλοντική ενασχόληση με το Deluge και με το ενδιάμεσο λογισμικό στα δίκτυα αισθητήρων γενικότερα. / Wireless sensor networks (WSNs) emerged about a decade ago, representing a new class of computing with large numbers of resource-constrained computing nodes cooperating on a single application. This thesis deals with middleware issues in wireless sensor networks. Specifically, we study Deluge that suggests the de facto over-the-air programming protocol for WSNs working under TinyOS. Providing a reliable and efficient data dissemination mechanism via the binary image of the program code, Deluge plays a key role in the middleware layer of WSNs. Gaining insight into Deluge, we implemented in the nesC programming language a simplified protocol that incorporates the main features of Deluge data dissemination mechanism. This implementation allowed us to evaluate further the propagation procedure of Deluge using a two-mechanism evaluation framework. Carrying out experiments both in real-world deployments being compatible with IEEE 802.15.4 radio and in a simulation environment (TOSSIM), we verified the efficient data propagation in WSNs, using Deluge.
This dissertation follows a structure of six chapters. In the first chapter, we give a piece of information about the subject field of this thesis. In the second chapter, we present an overall survey of the research area of WSNs and in the third chapter we examine the basic features of a sensor node (mote) whose wireless communication is based on an IEEE 802.15.4 compliant radio. In the fourth chapter, we discuss network programming in WSNs and we analyze the data dissemination mechanism of Deluge. In the fifth chapter, we discuss our implementation and its evaluation. Finally, in the sixth chapter, we conclude the thesis emphasizing the experience derived from that and we give some directions for future work with Deluge and middleware in WSNs generally.
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Minimum entropy techniques for determining the period of W UMA starsMcArthur, Ian Albert 08 1900 (has links)
This MSc report discusses the attributes of W Ursae Majoris (W UMa) stars and an investigation into the Minimum Entropy (ME) method, a digital technique applied to the determination of their periods of variability. A Python code programme was written to apply the ME method to photometric data collected on W UMa stars by the All Sky
Automated Survey (ASAS). Starting with the orbital period of the binaries estimated by ASAS, this programme systematically searches around this period for the period which corresponds to the lowest value of entropy. Low entropy here means low scatter (or spread) of data across the phase-magnitude plane. The ME method divides the light curve plot area into a number of elements of the investigators choosing. When a particular orbital period is applied to this photometric data, the resulting distribution of this data in the light curve plane corresponds to a speci c number of data points in each element into which this plane has been divided. This data spread is measured and calculated in terms of entropy and the lowest value of entropy corresponds to the lowest spread of data across the light curve plane. This should correspond to the best light curve shape available from the data and therefore the most accurate orbital period available. Subsequent to the testing of this Python code on perfect sine waves, it was applied, and its results compared, to the 62 ASAS eclipsing binary stars which were investigated by Deb and Singh (2011). The method was then applied to selected stars from the ASAS data base. / School of Environmental Sciences / M. Sc. (Astronomy)
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Extra OrdinaryWaldrep, Lana 01 January 2010 (has links)
The title of this thesis Extra Ordinary is intentionally ambiguous. Depending on how you read it, it can refer to either the very ordinary or to that which is outside of the ordinary.The works described within these pages functions similarly. From person to person and with time they move from the ordinary to beyond and back again. How can something be both mysterious and understood at the same time? How can I as a painter create a space where diametrically opposed forces can coexist and what is the effect of viewing such an object? This thesis addresses these issues with personal anecdote and through description of artwork and the art making process
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Opatření EU v oblasti letecké dopravy usnadňující volný pohyb osob, zboží a služeb - Jednotné evropské nebe / Measures of the EU in the area of air traffic facilitiating the free movement of persons, goods and services - the Single European SkyPysk, Vladimír January 2013 (has links)
This diploma thesis is dedicated to the European Commission's project known under the name Single European Sky which pursues an objective to reorganize the current European airspace structure for the more efficient provision of air navigation services purposes. As an introduction, the author sets himself the goal to acquaint the reader with relevant international organizations in the field of civil aviation, introduce him in a general way into the provision of air navigation services' issues, including the situations when these services are being provided across the national boundaries. Following this general reading, the thesis fluently moves on to its main subject matter which is the Single European Sky initiative. An attention is focused on the state of European airspace before the initiative has been launched as well as the preparatory works which resulted in the adoption of the first SES legislative package. The following chapter presents the basic legal framework regulating the Single European Sky as amended by the adoption of the second legislative package. Principal part of the thesis is comprised in the next chapter dealing with the process of project's implementation. Within its framework, the reader's attention is turned, inter alia, to such crucial issues as the national supervisory...
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Beginning all over again : a metaxological natural theology of the artsBrewer, Christopher R. January 2015 (has links)
Following Russell Re Manning, I acknowledge the diversity and persistence of natural theology. Going further than Re Manning, however, I propose a 5-type taxonomy stretching from natural theology as natural religion to natural theology as theology of nature. Having met this descriptive responsibility, I then turn in a second chapter to prescriptive possibility in dialogue with the Anglican theologian Howard E. Root (1926–2007). An early advocate of natural theology and the arts, Root called in his 1962 essay, “Beginning All Over Again,” for awareness (i.e., of the arts) rather than formal argument. Critiqued by E.L. Mascall and others, Root responded in his 1972 Bampton Lectures, “The Limits of Radicalism.” Never published, I discovered these lectures in an uncatalogued box at Lambeth Palace Library, London. Drawing upon these lectures, as well as other archival materials, I consider Root's contribution to a natural theology of the arts. That said, Root's work requires further development, and so in an effort to recover Root I have supplemented his contribution with the more recent work of David Brown, his unacknowledged theological heir. In an effort to recover Root more fully I turn in a third chapter to consider the philosopher William Desmond, the result of which is a metaxologically reformulated Root-Brown hybrid. In a fourth and final chapter, I consider the American contemporary artist Jonathan Borofsky and several others in order to see how this theoretical frame might be applied in practice as a metaxological natural theology of the arts.
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Ljusnivåns påverkan på rums- och ljusupplevelsen : Vid användning av virtuella takfönster som komplement i fönsterlösa rum / The influence of light level on room and light perception : When using virtual sky lights as a complement in windowless roomsMalin, Börjesson, Emma, Linde January 2019 (has links)
Denna studie syftar till att undersöka hur virtuella takfönster upplevs av människor i en väntrumsmiljö och diskuterar huruvida det är en lämplig lösning som komplement till saknaden av fönster. Tidigare forskning har bekräftat att det finns behov av att undersöka en alternativ belysningslösning i syfte att komplettera saknaden av fönster. Det uppsatta målet för den aktuella studien har därför varit att visa hur en belysningslösning i form av virtuella takfönster med hög eller låg ljusnivå, tillsammans med antingen hög eller låg ljusnivå på allmänljus upplevs. Med detta som grund har en experimentell studie genomförts med deltagare som har fått uppleva sex olika ljusscener i en väntrumsmiljö. Det som skiljde ljusscenerna åt var att de varierade mellan hög och låg ljusnivå på allmänljuset och på LED-panelerna som även var släckta i två ljusscener. Resultatet har visat att det finns ett samband mellan ljusnivån på de virtuella takfönsterna och rums- och ljusupplevelsen. Tända LED-paneler var något som deltagarna föredrog över släckta i ett väntrum, i kombination med allmänljus på en hög eller låg ljusnivå. Det var särskilt den tredje ljusscenen, när både allmänljuset och LED-panelerna hade en hög ljusnivå som utmärkte sig mest och gav ett positivt resultat. Det indikerar på att deltagarna föredrog denna ljusscen mest. Anledningen till varför kan bero på att kontrasten av ljuset upplevdes mest behaglig, jämfört med de fem övriga ljusscenerna. Vidare forskning inom området rekommenderas av författarna för att bidra till en djupare kunskap om hur virtuella takfönster ska appliceras för att skapa brukaranpassade ljusmiljöer i rum som saknar fönster. Upplevelsen av fler ljusnivåer gällande virtuella takfönster bör därför undersökas, samt att studier i fler typer av inomhusmiljöer borde undersökas, förslagsvis i studiemiljöer. Det kan bidra till en bredare kännedom kring applikationsmöjligheterna av virtuella takfönster, som komplement i fönsterlösa rum. / This study aims to examine how virtual sky lights are perceived by people and discuss whether it is a suitable solution as a complement to the lack of windows. Previous studies have confirmed that there is a need to examine an alternative lighting solution in order to supplement the lack of windows. The stated goal for the current study was therefore to evince how a lighting solution of virtual sky lights with a high or low light level, together with ambient lighting of either high or low light level is perceived. With this as a foundation, an experimental study has been conducted with participants who have experienced six different light scenes in a waiting room environment. The light scenes were distinguished between high and low light levels of the ambient lighting and of the LED-panels, which were also turned off in two light scenes. The result has shown that there is a connection between the light level of the virtual sky lights and the perception of the room and the lighting. The participants preferred the LED-panels when they were turned on rather than turned off in the waiting room, in combination with an ambient lighting at a high or low light level. It was especially the third light scene, when both the ambient lighting and the LED-panels had a high light level that excelled the most and showed positive results. It indicates that the participants preferred this light scene the most. It might be because the contrast of light was perceived most pleasantly, compared to the other five light scenes. Further studies within the field is recommended by the authors to contribute to a deeper knowledge about how virtual sky lights can be applied, to create user adapted lighting environments in rooms that lack windows. The perception of more light levels should therefore be investigated, also more types of environments should be investigated, study environments is one suggestion. It could contribute to a wider knowledge about possible application areas of virtual sky lights as a complement in windowless rooms.
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Minimum entropy techniques for determining the period of W UMA starsMcArthur, Ian Albert 08 1900 (has links)
This MSc report discusses the attributes of W Ursae Majoris (W UMa) stars and an investigation into the Minimum Entropy (ME) method, a digital technique applied to the determination of their periods of variability. A Python code programme was written to apply the ME method to photometric data collected on W UMa stars by the All Sky
Automated Survey (ASAS). Starting with the orbital period of the binaries estimated by ASAS, this programme systematically searches around this period for the period which corresponds to the lowest value of entropy. Low entropy here means low scatter (or spread) of data across the phase-magnitude plane. The ME method divides the light curve plot area into a number of elements of the investigators choosing. When a particular orbital period is applied to this photometric data, the resulting distribution of this data in the light curve plane corresponds to a speci c number of data points in each element into which this plane has been divided. This data spread is measured and calculated in terms of entropy and the lowest value of entropy corresponds to the lowest spread of data across the light curve plane. This should correspond to the best light curve shape available from the data and therefore the most accurate orbital period available. Subsequent to the testing of this Python code on perfect sine waves, it was applied, and its results compared, to the 62 ASAS eclipsing binary stars which were investigated by Deb and Singh (2011). The method was then applied to selected stars from the ASAS data base. / Environmental Sciences / M. Sc. (Astronomy)
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A rela??o entre o fator de vis?o do c?u e a temperatura do ar em diferentes zonas clim?ticas locais / The relationship between the sky view factor and air temperature across different local climate zonesSoeira, Marcelo Rezende Cal?a 28 January 2019 (has links)
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Previous issue date: 2019-01-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The objective of this research was to estimate and compare the Sky View
Factor (SVF) and Urban Heat Island Intensity (UHII) correlation across different
Local Climate Zones (LCZs) situated in the city of Campinas, S?o Paulo, Brazil.
The SVF consists of an non dimensional parameter which describes the ratio of
visible sky from a given point in space. In the urban environment, SVF values are
strongly related to buildings density and height. Also strongly related to the
densification and verticalization of the urban tissue is the Urban Heat Island
phenomenon, which is characterized by the elevation of air temperature in urban
environments as a result of its impact on the surface energy balance. For this
reason, research has been conducted in many countries to investigate the
correlation between SVF and the UHII. To evaluate the effects of urban tissue
composition on these correlations, however, systematic methods for detecting
and reporting such composition are required. Employing the Local Climate Zones
method, which classifies urban areas as climate zones according to their
structural typology and surface cover, this research evaluated SVF-UHII
correlation variations across different built up areas of the same city. Combining
mobile measurements and stationary monitoring devices a map of the nocturnal
UHII at the research site was obtained. According to seven parameters (H/W
ratio; SVF; Built area; Permeable area; Impermeable area; Height of roughness
elements; And roughness class), obtained by geoprocessing, eleven LCZs were
identified at the site. Nocturnal UHII linear regressions were calculated for SVF
values (point and 100m radius average values were used) at eight LCZs classes.
At compact low, low-high, mid-low and high-mid rise LCZs (3, 31, 23 and 12), with
SVF values between 0,20 and 0,45, the approximate air temperature increase
ranged from 1,5 up to 2,2?C. At compact low and mid-low rise LCZs (3 and 23),
with SVF values between 0,45 and 0,7, the approximate air temperature increase
ranged from 0,7 up to 1,2?C. For sparsely built low rise LCZs (6), with SVF
between 0,60 and 0,90, the approximate air temperature variation ranged from -
0,2 up to 0,0?C. From these results it was concluded that the correlation between
SVF and UHII is influenced by the morphological and superficial composition of
the urban tissue. Hence, to effectively utilize SVF in UHI mitigation strategies,
these influences should be considered. / A presente pesquisa teve como objetivo estimar e comparar as
correla??es entre o FVC e a varia??o da temperatura do ar encontradas em
diferentes zonas clim?ticas situadas em um recorte da cidade de Campinas- SP.
O fator de vis?o do c?u (FVC) ? um par?metro adimensional utilizado para
descrever a propor??o de c?u vis?vel, em um determinado local, a partir do n?vel
do solo. No ambiente urbano, seu valor est? fortemente relacionado ao grau de
compacta??o e verticaliza??o da malha construtiva. Outro fen?meno relacionado
ao grau de compacta??o e verticaliza??o da malha urbana ? o fen?meno da Ilha
de Calor Urbana (ICU), caracterizado pela reten??o do calor absorvido no
ambiente constru?do. Por este motivo, ? grande o n?mero de pesquisas que
estudam a correla??o entre o FVC e o fen?meno da Ilha de Calor Urbana em
diversas cidades do mundo. Atrav?s de m?todos sistem?ticos para o
reconhecimento e documenta??o de heterogeneidades da malha urbana, como
o m?todo das Zonas Clim?ticas Locais (LCZs), que classifica ?reas urbanas em
zonas clim?ticas locais de acordo com sua tipologia construtiva e cobertura de
superf?cies, tornou-se poss?vel avaliar a varia??o desta correla??o em um
contexto intramunicipal. Atrav?s de campanhas de medi??es m?veis e de pontos
fixos de monitoramento, a intensidade da ilha de calor urbana na ?rea de estudo
foi avaliada. A ?rea de estudo foi classificada em onze LCZs de acordo com sete
par?metros urban?sticos obtidos por geoprocessamento (rela??o altura-largura,
FVC, ?rea edificada, ?rea imperme?vel, ?rea perme?vel, altura m?dia dos
elementos de rugosidade e classe de rugosidade). Regress?es lineares foram
estabelecidas entre a intensidade da ICU ?s 21:00 e valores de FVC (pontuais e
m?dios para um raio de 100m) em ?reas de an?lise correspondentes a oito LCZs.
Para valores de FVC entre 0,20 e 0,45, a eleva??o aproximada da temperatura
do ar em LCZs de arranjo compacto e verticaliza??o baixa a m?dia-alta ? 1,5 a
2,2 ?C; para valores de FVC entre 0,45 e 0,7 em LCZs de arranjo compacto e
verticaliza??o baixa e m?dia-baixa, a eleva??o aproximada da temperatura do ar
foi de 0,7 a 1,5 ?C; e para valores de FVC entre 0,60 e 0,90 em LCZs de arranjo
esparso e verticaliza??o baixa, a varia??o aproximada da temperatura do ar foi
de 0,0 a -0,2 ?C. Assim, conclui-se que a influ?ncia do FVC na eleva??o da
temperatura do ar em ?reas urbanizadas varia conforme a composi??o
morfol?gica e superficial do tecido urbano. Para que o FVC seja utilizado
efetivamente em estrat?gias de mitiga??o da ICU, essa rela??o deve ser
considerada.
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