Dans ce manuscrit, nous développons des méthodologies de détection et caractérisation de sources géomagnétiques et atmosphériques en se basant sur la transformée en ondelettes continues. Les techniques introduites se basent sur les caractéristiques temps-fréquence des ondes observées dans les séries temporelles magnétotelluriques (MT). A partir de ces procédures de détection, nous détaillons l'implémentation d'une stratégie de détermination des fonctions de réponse MT basée sur les statistiques robustes, et du bootstrap hiérarchique pour le calcul des incertitudes. Deux études MT sont également détaillées. La première étude MT concerne la caractérisation de la structure géoélectrique situé sous l'observatoire magnétique de Chambon-La-Forêt, France. La seconde étude concerne des mesures effectuées dans la vallée de Trisuli au Népal en mars 2016. L'objectif de cette campagne est la comparaison avec une étude effectuée en 1996. Nous discutons des effets topographiques sur les sondages MT. Nous présentons également une nouvelle interprétation de la distribution de conductivité dans le sous-sol de vallée de Trisuli. / In this manuscript, we detail the application of continuous wavelet transform to processing schemes for the detection and the characterisation of geomagnetic and atmospheric sources. Presented techniques are based on time-frequency properties of electromagnetic (EM) waves observed in magnetotellurics (MT) time series. We detail the application of these detection procedures in a MT processing scheme. To recover MT response functions, we use robust statistics and a hierarchical bootstrap approach for uncertainties determination. Interpretation of two datasets are also presented. The first MT study deals with the caracterisation of the resistivity distribution below the French National magnetic observatory of Chambon-la-Forêt. The second study details the interpretation of new MT soundings acquired in March 2016 in the Trisuli valley, Nepal. The main objective of this campaign was to compare the new soundings with an old campaign in 1996. We discuss topography effects on MT soundings and their implication on the resistivity distribution. We also introduce a new interpretation of the resistivity distribution in Trisuli valley.

O observatório cultural é um dispositivo de informação, típico da sociedade contemporânea, que se apropria de metodologias e teorias interdisciplinares para acompanhar e compreender o campo cultural. Os observatórios culturais surgem, no Brasil, no final da década de 1980 e se desenvolvem especialmente a partir da segunda metade da década 1990, atingindo o maior número de instituições nos anos 2000. Primeiramente associados aos estudos das políticas culturais, em universidades, passam a dedicar esforços a questões culturais específicas dos setores criativos, dos movimentos sociais e dos meios de comunicação, sendo incorporados por diferentes esferas: pública, privada, terceiro setor e sociedade civil. A partir da pesquisa dos conteúdos dos sites de 15 observatórios brasileiros, são analisados os contextos, as motivações e as circunstâncias de criação, assim como as formas de atuação, práticas e atividades desses órgãos. Quanto aos propósitos, eles podem ser classificados como de monitoramento ou \"fiscais\", de reflexão ou think tank, conforme a literatura, e \"de apropriação\", a partir da contribuição desta pesquisa. Em geral, predomina a produção de conteúdos analíticos; a edição de livros, revistas, artigos, textos, publicações digitais e audiovisuais; a coleta de informações em \"bancos de dados\" e a promoção de atividades de difusão: palestras, oficinas, cursos rápidos, encontros. Entre os pontos de vulnerabilidade na atuação, devido aos recursos de que dispõem, encontram-se: o trabalho em rede, a comunicação com os diferentes públicos, a produção de indicadores culturais e o compartilhamento de conteúdos e metodologias. A contribuição principal dos observatórios se identifica, sobretudo, pela criação de uma \"cultura\" das práticas de pesquisa e observação e pelo reconhecimento de sua importância para a ação política. No caso brasileiro, a apropriação desse tipo de dispositivo de informação por setores da sociedade civil e pelos movimentos sociais significa um propósito novo ou uma ampliação da ação política dos grupos. / Cultural observatories are apparatuses of information, typical of contemporary society, that absorb interdisciplinary methodology and theory to follow and comprehend the field of culture. Cultural observatories emerged in Brazil in the late 1980s, but developed themselves more assertively throughout the late 1990s and reached an increased number of institutions in the new millenium. Initially associated to the study of cultural policies in universities, they went on to analyze specific cultural issues related to creative sectors, social movements and media and are now being incorporated to public, private and third sectors and to the civil society. Their contexts, motivations, circumstances of creation as well as operation manner, practices and activities were analyzed based on the online content of 15 different Brazilian observatories. As for their purposes, they can be classified as monitoring or \"inspectors\", reflexive or think tanks or as \"appropriation\", as defined by this research. In general, the production of analytical content is their predominant activity, which includes: literature, magazines, scientific articles and texts, digital and audio-visual publishing, the gathering of information in data banks and the promotion of disseminating activities like lectures, workshops, quick courses and congresses. The observatories\' vulnerabilities, due to their scarce resources, include: work through networking, communication with a diverse audience, the production of cultural indicators and the sharing of content and methodology. The main contribution of these observatories is their participation in creating a \"culture\" of observation and research practices as well as recognition of their importance to political action. In the case of Brazil, the appropriation of this kind of information apparatus by sectors of civil society and by social movements reveals a new or amplified purpose of political activity among these groups.

M. Tech. Architecture (Professional) / Over the last decade, South Africa (RSA) has experienced a substantial growth in the field of astronomy and astrophysics. Post 2005, the largest optical telescope in the Southern hemisphere, known by its acronym, SALT, was constructed in RSA. It is expected that by 2024, this country will host the largest array of radio telescopes in the world, the Square Kilometre Array (SKA). It could be argued that RSA is at the forefront of modern cosmological research. This exponential growth in the field of astronomy has resulted in local astronomical bodies and universities falling behind in astronomy education. This provides a unique opportunity to strengthen the latter. The aim of this dissertation is to design an International School of Astronomy and Astro-Tourism Centre. The proposed building aims to introduce a unique facility in the Northern Cape that would benefit the field of astronomy worldwide. The proposed facility is situated at the South African Astronomical Observatory (SAAO) in Sutherland. It is nested within the South-west-embankment of the mountain, currently hosting the Southern Africa Large Telescope (SALT). The resultant design takes on a linear building typology with radial aspects to document astronomical events. The project investigates the semi-arid Karoo climate and how the resultant architecture reacts to harsh environmental conditions.

[Truncated abstract] Interferometric gravitational wave detectors are being built around the world with continually improving measurement sensitivities. Noise levels from sources that are intrinsic to these detectors must be reduced to a level below the gravita- tional wave signal. Seismic noise in the low frequency range, which is within the gravitational wave detection bandwidth, is a concern for earth-based detectors. This thesis presents research and development of a high performance vibration isolation system that is designed to attenuate seismic noise. The final design will be used as part of a fully working interferometer at the Australian International Gravitational Observatory (AIGO). Pendulums and springs are conventionally used for the horizontal and vertical vibration isolation components respectively. A complete system comprises of a cascade of these components, each stage dramatically improving the level of isola- tion. The residual motion at the test mass level is thus reduced but is dominated by the normal mode resonances of the chain. A simple and effective method to reduce residual motion further is to add ultra-low frequency pre-isolation stages which suspend the chain. The Roberts Linkage is a relatively new and simple geometrical structure that is implemented in the pre-isolation stages. Here we present experimental results of improving isolation based on mathematical mod- elling. The attenuation of seismic noise in the vertical direction is almost as important as that in the horizontal direction, due to cross-coupling between the two planes. To help improve the vertical performance a lightweight Euler spring that stores no static energy was implemented into the AIGO suspension system. ... Theoretical and experimental results are presented and discussed. Currently the AIGO laboratory consists of two 80 m length arms. They are aligned along the east and south directions. One of AIGO's top priorities is the installation of two complete vibration isolators in the east arm to form a Fabry-Perot cavity. Assembling two suspension systems will enable more accurate performance measurements of the tuned isolators. This would significantly reduce the measurement noise floor as well as eliminate the seismic noise spectrum due to referencing with the ground motion. The processes involved in preparing such a task is presented, including clean room preparation, tuning of each isolator stage, and local control schematics and methods. The status of the AIGO site is also presented.

Thesis (M.A.)--West Virginia University, 2010. / Title from document title page. Document formatted into pages; contains v, 78 p. Includes abstract. Includes bibliographical references (p. 64-78).

Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Superconducting QUantum Interference Devices (SQUIDs) are fairly recent types of magnetometers that use flux quantization combined with Josephson tunnelling to detect very faint (< 10¯15 T) magnetic fields. Recent scientific studies have shown that these highly sensitive magnetometers, located in an ultra-low-noise environment, are capable of observing Earth-ionosphere couplings, such as P waves emitted during earthquakes or magnetic storms in the upper atmosphere, S and T breathing modes of the Earth during quiet magnetic and seismic periods, signals in time correlating with sprites. Since SQUIDs are much more sensitive than conventional magnetometers, they are arguably the best tool for understanding space weather and natural hazards, whether they are produced from space or within the ionosphere by magnetic storms for instance, or natural disturbances, including magnetic disturbances produced by earthquakes or as a result of the dynamics of the earth's core. A study was conducted at SANSA Space Science in Hermanus, Western Cape, in 2012, to find the correlation between SQUID and Fluxgate data-sets, with the aim of validating the use of a SQUID as a reliable instrument for Space Weather observations. In that study, SQUID data obtained from the Low Noise Laboratory (LSBB) in France was compared to Fluxgate data-sets from the three closest magnetic observatories to LSBB, namely Chambon la For êt (France), Ebro (Spain) and Fürstenfeldbruck (Germany), all further than 500 km from LSBB. As a follow-up study, our aim is to correlate the SANSA Space Science SQUID data at Hermanus with Fluxgate magnetic data also recorded on-site (at Hermanus). There are notable di_erences between the previous study and the current study. In the previous study, the three-axis SQUID used comprised of three low-Tc devices operated in liquid helium (4.2 K) in an underground, low noise environment shielded from most human interferences. The SQUID magnetometer operated at Hermanus for the duration of this study is a high-Tc two-axis device (measuring the x and z components of the geomagnetic field). This SQUID magnetometer operates in liquid nitrogen (77 K), and is completely unshielded in the local geomagnetic field of about 26 uT. The environment is magnetically clean to observatory standards, but experiences more human interference than that at LSBB. The high-Tc SQUIDs also experience excessive 1/f noise at low frequencies which the low-Tc SQUIDs do not suffer from, but the big advantage of the current study is that the SQUIDs are located within 50 m from the observatory's fluxgate. We thus expect far better correlation between SQUID and fluxgate data than what was obtained in the previous study, which should improve the isolation of signals detected by the SQUID but not by the fluxgate. / AFRIKAANSE OPSOMMING: SQUIDs (supergeleidende kwantuminterferensietoestelle) is redelik onlangse tipes magnetometers wat vloedkwantisering saam met Josephson-tonneling gebruik om baie klein (< 10¯15 T) magnetiese velde waar te neem. Onlangse wetenskaplike studies het getoon dat hierdie hoogs sensitiewe magnetometers die vermoë het om Aarde-ionosfeerkoppeling waar te neem wanneer dit in 'n ultra-laeruisomgewing geplaas word. Sodanige koppeling sluit in: P-golwe wat deur aardbewings or magnetiese storms in die boonste atmosfeer veroorsaak word; S- en T-asemhalingsmodusse van die Aarde gedurende stil magnetiese en seismiese periodes; en seine in tyd wat korreleer met weerligeffekte in die boonste atmosfeer. Aangesien SQUIDs heelwat meer sensistief is as konvensionele magnetometers, is dit moontlik die beste gereedskap om ruimteweer en geassosieerde natuurlike gevare mee te analiseer; hetsy sulke toestande veroorsaak word vanaf die ruimte (deur die son) of binne die ionosfeer deur magnetiese storms of natuurlike steurings wat deur aardbewings of die dinamika van die Aardkern veroorsaak word. 'n Studie is in 2012 gedoen by SANSA Space Science in Hermanus in die Wes-Kaap om die korrelasie tussen SQUID- en vloedhekdatastelle te vind met die doel om SQUIDs as betroubare instrumente vir ruimteweerwaarneming te bevestig. In daardie studie is SQUID-data verkry vanaf die Laeruis Ondergrondse Laboratorium (LSBB) in Frankryk, en is dit vergelyk met vloedhekdatastelle vanaf die drie naaste magnetiese observatoriums aan LSBB, naamlik: Chambon la Forêt (Frankryk), Ebro (Spanje) en Fürstenfeldbruck (Duitsland). Al drie hierdie observatoriums is verder as 500 km vanaf LSBB. As 'n opvolgstudie is ons doelwit om SQUID- en vloedhekdata wat beide op die terrein van SANSA Space Science in Hermanus waargeneem word, te korreleer. Daar is merkbare verskille tussen hierdie en die vorige studies. In die vorige studie is 'n drie-as lae-Tc SQUID-magnetometer in vloeibare helium (4.2 K) in 'n laeruis ondergrondse laboratorium, afgeskerm teen menslike steurings, gebruik. Die SQUID-magnetometer wat vir die duur van die huidige studie by Hermanus gebruik is, is 'n hoë-Tc twee-as toestel (wat die x - en z -komponente van die geomagnetiese veld meet). Hierdie SQUID-magnetometer opereer in vloeibare stikstof teen 77 K, sonder enige afskerming in die geomagnetiese veld van ongeveer 26 uT. Die omgewing is magneties skoon volgens observatoriumstandaarde, maar ondervind meer menslik-veroorsaakde steurings as LSBB. Die hoë-Tc SQUIDs tel ook heelwat 1/f ruis op (wat lae-frekwensiemetings beïnvloed); iets wat nie 'n rol speel by die lae-Tc SQUIDs nie. Die groot voordeel van die huidige studie is dat die SQUIDs binne 50 meter vanaf die observatorium vloedhekke geleë is. Ons verwag dus heelwat beter korrelasie tussen SQUID- en vloedhekdata as wat met die vorige studie verkry is, wat dit makliker sal maak om die isolasie te verbeter van seine wat deur die SQUIDs waargeneem is, maar nie deur die vloedhekke nie.

O observatório cultural é um dispositivo de informação, típico da sociedade contemporânea, que se apropria de metodologias e teorias interdisciplinares para acompanhar e compreender o campo cultural. Os observatórios culturais surgem, no Brasil, no final da década de 1980 e se desenvolvem especialmente a partir da segunda metade da década 1990, atingindo o maior número de instituições nos anos 2000. Primeiramente associados aos estudos das políticas culturais, em universidades, passam a dedicar esforços a questões culturais específicas dos setores criativos, dos movimentos sociais e dos meios de comunicação, sendo incorporados por diferentes esferas: pública, privada, terceiro setor e sociedade civil. A partir da pesquisa dos conteúdos dos sites de 15 observatórios brasileiros, são analisados os contextos, as motivações e as circunstâncias de criação, assim como as formas de atuação, práticas e atividades desses órgãos. Quanto aos propósitos, eles podem ser classificados como de monitoramento ou \"fiscais\", de reflexão ou think tank, conforme a literatura, e \"de apropriação\", a partir da contribuição desta pesquisa. Em geral, predomina a produção de conteúdos analíticos; a edição de livros, revistas, artigos, textos, publicações digitais e audiovisuais; a coleta de informações em \"bancos de dados\" e a promoção de atividades de difusão: palestras, oficinas, cursos rápidos, encontros. Entre os pontos de vulnerabilidade na atuação, devido aos recursos de que dispõem, encontram-se: o trabalho em rede, a comunicação com os diferentes públicos, a produção de indicadores culturais e o compartilhamento de conteúdos e metodologias. A contribuição principal dos observatórios se identifica, sobretudo, pela criação de uma \"cultura\" das práticas de pesquisa e observação e pelo reconhecimento de sua importância para a ação política. No caso brasileiro, a apropriação desse tipo de dispositivo de informação por setores da sociedade civil e pelos movimentos sociais significa um propósito novo ou uma ampliação da ação política dos grupos. / Cultural observatories are apparatuses of information, typical of contemporary society, that absorb interdisciplinary methodology and theory to follow and comprehend the field of culture. Cultural observatories emerged in Brazil in the late 1980s, but developed themselves more assertively throughout the late 1990s and reached an increased number of institutions in the new millenium. Initially associated to the study of cultural policies in universities, they went on to analyze specific cultural issues related to creative sectors, social movements and media and are now being incorporated to public, private and third sectors and to the civil society. Their contexts, motivations, circumstances of creation as well as operation manner, practices and activities were analyzed based on the online content of 15 different Brazilian observatories. As for their purposes, they can be classified as monitoring or \"inspectors\", reflexive or think tanks or as \"appropriation\", as defined by this research. In general, the production of analytical content is their predominant activity, which includes: literature, magazines, scientific articles and texts, digital and audio-visual publishing, the gathering of information in data banks and the promotion of disseminating activities like lectures, workshops, quick courses and congresses. The observatories\' vulnerabilities, due to their scarce resources, include: work through networking, communication with a diverse audience, the production of cultural indicators and the sharing of content and methodology. The main contribution of these observatories is their participation in creating a \"culture\" of observation and research practices as well as recognition of their importance to political action. In the case of Brazil, the appropriation of this kind of information apparatus by sectors of civil society and by social movements reveals a new or amplified purpose of political activity among these groups.

La bioluminescence est l’émission de lumière par des organismes vivants. En milieu bathypélagique, où l’absence de lumière est une caractéristique majeure, ce phénomène semble avoir un rôle écologique primordial dans les interactions biologiques ainsi que dans le cycle du carbone. Ce travail cherche à déterminer si la bioluminescence peut être définie comme un proxy de l’activité biologique en milieu profond. Cette étude multidisciplinaire développe à la fois une approche in situ et en laboratoire. Le télescope ANTARES, immergé en Méditerranée, à 2475 m de profondeur, a joué le rôle d’un observatoire océanographique enregistrant la bioluminescence ainsi que les variables environnementales à haute fréquence. L’analyse de ces séries temporelles, non-linéaires et non-stationnaires a permis de mettre en évidence deux périodes de forte activité de bioluminescence en 2009 et 2010. Ces évènements ont été expliqués par des phénomènes de convection dans le Golfe du Lion, impactant indirectement la bioluminescence enre- gistrée sur ANTARES. En laboratoire, la bioluminescence bactérienne a été décrite sur une souche modèle piezophile, isolée au cours d’un évènement de forte bioluminescence. La pression hydrostatique liée à la profondeur in situ (22 MPa) induit une plus forte bioluminescence qu’à pression atmosphérique (0.1 MPa). Enfin, le suivi des communautés procaryotiques profondes a été réalisé, sur le site ANTARES, au cours de l’année 2011. Ce suivi a montré la présence de 0.1 à 1% de bactéries bioluminescentes dans une période enregistrant une faible activité de bioluminescence. Ces cellules ont été définies comme majoritairement actives. / Bioluminescence is the emission of light by living organisms. In the bathypelagic waters, where darkness is one of the main characteristic, this phenomenon seems to play a major role for biological interactions and in the carbon cycle. This work aims to determine if bioluminescence can be considered as a proxy of biological activity in the deep sea. This multidisciplinary study develops both in situ and laboratory approaches. The ANTARES telescope immersed in the Mediterranean Sea at 2,475 m depth has been used as an oceanographic observatory recording bioluminescence as well as environmen- tal variables at high frequency. This time series analysis, defined as non linear and non stationary, highlighted two periods of high bioluminescence intensity in 2009 and 2010. These events have been explained by convection phenomena in the Gulf of Lion, indi- rectly impacting the bioluminescence sampled at this station. In the laboratory, bacterial bioluminescence has been described using a piezophilic bacterial model isolated during a high-bioluminescence-intensity event. Hydrostatic pressure linked to the in situ depth (22 MPa) induces a higher bioluminescence activity than under atmospheric pressure (0.1 MPa). Then, the survey of the deep prokaryotic communities has been done at the AN- TARES station, over the year 2011. This survey shows the presence of about 0.1 to 1% of bioluminescent bacteria even during a low-bioluminescence-activity period. These cells were mainly actives.

According to the United Nations more than half of humanity live today in cities, and by 2050 seventy percent of the world’s population is projected to be urban. This means that there will be a transformative role of cities at all levels in the coming decades. In general, Local governments have the responsibility to provide their people with basic services to improve their living standards because democracy is also measured in terms of quality of life and the common good. Through the case study of Los Cabos Citizen Observatory (ICO) in Los Cabos, Baja California Sur, Mexico, we have analyzed and learned that a conscious, competent, credible, collective, collaborative, continuous and communicative citizen par-ticipation can occur with the use of ISO 18091 international standard. With this tool, not only can citizens evaluate the administration's action in an integral way but also offer pro-posals of value for the improvement of public services and policies which eventually be-come strategic axes of municipal development plan for a good governance. Therefore, ICOs are Building a Reliable Citizen Participation for Local Government which can be pre-sented as 'one valid global way' to improve Democracy and Participation in the 21st cen-tury that are promoted and practiced starting from the cities.

Madagascar est un pays riche en ressources naturelles mais sa population reste pauvre et vit dans un écart de revenus important. Cette étude aborde le thème des "Inégalités de revenus des ménages en milieu rural malgache" afin de pouvoir apporter des éclaircissements à ce phénomène qui, d’une part, ruine la population rurale et, d’autre part, fragilise la stabilité et la performance économique du pays. Focalisée sur une période quinquennale d’observations répétées, la thèse porte sur les données de panel issues de 667 ménages. La thèse retrace le processus de calculs des revenus des paysans et du "seuil d’inégalité". Adoptant les modèles linéaire et non-linéaire, il s’attache aux spécifications et aux estimations des déterminants qui creusent ou réduisent les écarts de revenus des ménages intra-observatoires et entre observatoires de la côte Centre-Est. Les inégalités de revenus des ménages ruraux existent dans la société rurale Betsimisaraka. Elles sont multiformes. Plus de huit ménages sur dix vivent dans la "zone des pauvres inégalitaires". Les paysans de Mahanoro sont les plus pauvres et subissent aussi plus d’inégalités que ceux de Fénérive-Est. En revanche, à l’intérieur de l’observatoire, la situation a légèrement tendance à décroître au fil du temps. Pour une population assez homogène vivant dans une pauvreté alarmante, les inégalités entre ménages pauvres ne sont pas trop élevées. Les résultats des modèles économétriques soutiennent que la bonne production annuelle de riz réduit les écarts de revenus tandis que le sexe féminin et le niveau d’éducation du chef de ménage, la faible superficie rizicole ainsi que l’investissement, le dépôt financier, la thésaurisation, le sans épargne, l’emprunt, les revenus secondaires, le PIB et la crise politique accentuent les inégalités de revenus / Madagascar is a country rich in natural resources, but its population is poor and lives in a significant income gap. This thesis deals with the issue of "household income inequalities in rural areas in Madagascar", in order to clarify this phenomenon which, on the one hand, ruin the rural population and on the other hand, weakens the country's stability and the economic performance. Covering a five-year period of repeated observations, this thesis focuses on data from 667 households, from a balanced panel. The thesis traces the calculation process of farmers’ income and “inequality threshold”. Adopting linear and non-linear models, it endeavors to specify and estimate determinants that increase or reduce the wealth gap within and between observatories of the Central East Coast of Madagascar. Income inequalities of rural households are found in Betsimisaraka rural society. They are multifaceted. More than eight out of ten households live in the “area of unequal poors”. The farmers in Mahanoro are poorer and suffer more inequalities than in Fenerive Est. However, inside the observatory, the situation slightly tends to increase over time. For a rather homogeneous population living in alarming poverty, the inequalities between poor households are not too high. The results of econometric models argue that the good annual production of rice reduces income disparities, whereas the feminine gender and the education level of the household head, the small size of rice area along with the investment, the financial deposit, the hoarding, the "No savings", the debt, the secondary income, the GDP and the political crisis contribute to greater income inequalities.