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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.
321

Avanços e limites da regularização fundiária na Vila Brandina (Campinas - SP) / Regularization of urban land in Porto Alegre : Vila Brandina , the study of a place

Rocha, Cristiano Silva da, 1976- 30 August 2012 (has links)
Orientador: Claudete de Castro Silva Vitte / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociencias / Made available in DSpace on 2018-08-21T15:23:29Z (GMT). No. of bitstreams: 1 Rocha_CristianoSilvada_D.pdf: 7077234 bytes, checksum: 03f4553b51d3e67897a0e2a5ea5976aa (MD5) Previous issue date: 2012 / Resumo: O objetivo desta tese foi contribuir na compreensão da produção do espaço urbano de Campinas, considerando os programas de regularização fundiária urbana no município, em especial no período de 1980 a 2010. O período escolhido compreende anos de crise econômica, de políticas neoliberais sucedidas por período recente de maior intervenção governamental no país, com algumas políticas voltadas ao atendimento de demandas históricas por parte das classes sociais mais vulneráveis. Na Vila Brandina, uma das mais antigas favelas de Campinas, realizamos um censo comunitário que serviu de base para os estudos da regularização fundiária na escala do lugar. A Vila Brandina apresenta um histórico de luta pelo direito à moradia, sendo uma das mais antigas ocupações do município. Ela é uma comunidade localizada em uma área que se valorizou sobremaneira na cidade de Campinas, mas é marcada por carências de alguns serviços e equipamentos públicos. O estudo apontou para a ineficácia das ações de regularização fundiária que se resumiram a ações pontuais e promessas não cumpridas pelo poder público. A partir das experiências selecionadas, a nossa tese é de que as políticas de regularização fundiária não tem sido capazes de garantir a efetivação do direito à moradia e o combate à segregação sócio-espacial. Para tanto fizemos o levantamento e a análise da legislação e dos instrumentos relacionados à questão e constatamos que, embora haja uma grande diversidade de projetos, programas e ações, esse conjunto não está sendo suficiente para garantir o pleno direito à moradia adequada das famílias moradoras de áreas irregulares e nem seu direito à cidade / Abstract: The purpose of this thesis was contribute in the understanding of urban space production of Campinas, considering the urban land regularization programs in the city, particularly in the period 1980 to 2010. The selected period comprises years of economic crisis, of neoliberal policies succeeded by recent period of greater government intervention in the country, with some policies aimed at meeting demands by the most vulnerable classes. In Vila Brandina, one of the oldest slums of Campinas, we conducted a community census, which was the basis for studies of land regularization in the scale of the place. The Village Brandina, one of the earliest occupations of the city, presents a history of struggle for housing rights. It is a community located in an area that has valued greatly in the city of Campinas, but is marked by shortages of some services and public facilities. The study pointed to the ineffectiveness of the actions of regularization, which were summarized by isolated actions, and unfulfilled promises, of the governments. From the experiences selected, our thesis is that the politics of land tenure has not been able to ensure the realization of housing rights and combat social and spatial segregation. To do so we did a survey and analysis of legislation and instruments related to the issue and we found that, although there are a wide variety of projects, programs and actions, this set is not sufficient to guarantee the full right to adequate housing of families living in areas irregular and his right to the city / Doutorado / Análise Ambiental e Dinâmica Territorial / Doutor em Geografia
322

[en] EFFECTS OF DIFFERENT URBAN ENVIRONMENTS ON THE PROPAGATION OF SIGNALS FROM PERSONAL COM. SYSTEMS BASED ON NON GEOSTATIONARY ORBIT SATELLITE NETWORKS / [pt] EFEITOS DE DIFERENTES REGIÕES URBANAS NA PROPAGAÇÃO DE SINAIS DE SISTEMAS DE COMUNICAÇÕES PESSOAIS BASEADOS EM REDES DE SATÉLITES NÃO GEOESTACIONÁRIOS

PEDRO PAULO SUZANO XAVIER 25 July 2005 (has links)
[pt] À medida que os sistemas de comunicações móveis e de rádiodeterminação que utilizam satélites não geo-estacionários de órbitas baixas e médias ganham importância no cenário mundial de comunicações, torna-se cada vez mais necessário o conhecimento do ambiente de rádio- propagação, seu comportamento e a inter-relação entre os seus diversos aspectos e parâmetros. Em função de características dos dispositivos de comunicações utilizados em tais sistemas, como transmissores de baixa potência e antenas de baixo ou médio ganho, esses sistemas operam com margens de desvanecimento relativamente baixas. A literatura descreve uma técnica de simulação para estimação de margens de desvanecimento em diversos tipos de ambiente baseada em fotografias obtidas com a utilização de câmaras providas de lentes grande-angulares. Na presente dissertação, apresenta-se uma variante da metodologia original, onde se propõe a substituição da base de dados original por mapas digitais da topografia, combinada com bases de dados de edificações e de um modelo para a vegetação. Apresenta-se, ainda, a estrutura da simulação computacional utilizada para processar e analisar tais arquivos, os dados de entrada da simulação e um módulo que representa a dinâmica orbital, utilizado para prever as posições dos satélites. Finalmente, apresentam-se e analisam-se os resultados obtidos com a presente simulação. Analisa-se, também, a influência da variação dos diversos fatores que compõem os dados de entrada da simulação nos resultados obtidos. / [en] As land-mobile satellite systems and radio-determination systems get more importance in the global telecommunications scenario, it becomes even more necessary to understand the radio-propagation environment: its behavior and the inter-relationship between its several aspects and physical parameters. Due to the communications devices characteristics used in these systems, such as low-power transmitters and low/medium gain antennas, such systems operate with relatively low fade margins. The technical literature describes a simulation technique to estimate fade margins in various types of environments, based on the processing of photographs acquired by digital cameras utilizing fisheye lenses. In this dissertation, an alternate methodology is presented. It is proposed that the original database of photographs be substituted by digital elevation models combined with building databases and a vegetation model. The computer simulation structure used to process and analyzes these databases, the input simulation data, and an orbital dynamics model used to update the satellite positions are also described. Finally, the obtained simulation results are presented and analyzed. It also discusses the influence of several factors which characterize different urban regions and non geostationary orbit satellite networks in the obtained results.
323

Un quartiere della Roma imperiale : il foro di Traiano nel suo contesto urbano : modifica del paesaggio, soluzioni architettoniche e sistemi di circolazione / Un quartier de la Rome impériale : le forum de Trajan dans son environnement urbain : modifications du paysage, solutions architecturales et système de circulation / A quarter of imperial Rome : the Trajan's forum in its urban environment : modification of landscape, architectural solutions and circulation system

Taffetani, Claudio 08 July 2016 (has links)
Le projet urbanistique et architectural lié à la construction du forum de Trajan à Rome (106 et 113 ap. J.-C) s’inscrit dans la tradition de ceux qui l’ont précédé. Pourtant ses dimensions et les travaux colossaux nécessaires à son établissement en font un projet particulièrement exceptionnel qui a entraîné la transformation totale de l’ensemble de la zone située entre les collines du Capitole et du Quirinal. Cette étude porte sur les modalités de ce réaménagement et ses conséquences non seulement sur la zone du forum, mais également sur l’ensemble du tissu urbain de la ville. Il s’agit d’analyser ce grand programme architectural en soulignant, comment, au-delà de la réalisation de la place publique, a été conçu, autour du complexe impérial, tout un ensemble urbanistique cohérent et surtout entièrement structuré par un nouveau système de circulation complexe. Le contexte urbain avant et après la réalisation du forum sont successivement étudiés et une attention particulière est accordée aux solutions architecturales adoptées afin d’intégrer les nouvelles constructions dans le tissu urbain préexistant. L’objectif est de reconstruire chronologiquement toute l’organisation urbanistique de la zone et de déterminer dans quelle mesure la construction du forum de Trajan a conditionnée le développement de l’Urbs dans son ensemble. / The urban and architectural project related to the construction of the Trajan Forum in Rome (106-113 AD) joins the tradition of its predecessors. However, its dimensions and the colossal work needed for its creation make it a one-of-a-kind project, which caused the transformation of the whole area between the Campidoglio and Quirinale hills. This study focuses on the methods of this transformation and on its impact on the proper Forum area, and on the rest of the city’s urban texture. It is an analysis of this big architectural project, beyond the public square, with particular attention to the collection of architectural solutions and to the complicated system of paths created around the imperial complex. The urban context was analysed in parallel, before and after the completion of the Forum, in order to understand better the architectural solutions adopted, and to integrate the new buildings in the pre-existing urban context. The objective is to chronologically reconstruct the whole urban setup of the area, and to determine to which extent the construction of the Trajan Forum conditioned the development of this part of the empire-period Urbs.
324

Standardiserade flerbostadshus - En utredning om en hållbar förtätning av stadskärnan / Standardized multifamily housing – An investigation of sustainable urban densification

Omerovic, Damir, Kronkvist, Amanda January 2017 (has links)
No description available.
325

Creating Healthy Urban Environments: Commercial Landscaping, Preference and Public Health

Leibe, Mary 16 December 2016 (has links)
Landscape development[1] can provide many benefits, including the reduction of stormwater runoff and the creation of habitats for wildlife. It can also provide health benefits. Researchers, such as Roger Ulrich and Rita Berto have demonstrated that views of trees and other vegetation are associated with lower blood pressure and reduced recovery times in hospitals and that environments with more natural elements may lessen mental fatigue (R. Ulrich 1984) and (Berto 2005). As rebuilding in New Orleans continues 11 years after Hurricane Katrina, landscape development has been limited or lacking, especially in the redevelopment of commercial properties. Two prominent reasons for this deficiency are a lack of funding and, until August of 2015, the absence of a comprehensive landscape ordinance. The purpose of the research presented here is to determine the degree to which community residents express a preference for healthier commercial environments. As part of my research, I measured community perceptions of four potential redevelopment concepts for a blighted strip shopping center utilizing attention restoration theory (ART), which postulates that certain environmental qualities contribute to reductions in mental fatigue. I found that commercial environments with the most quality landscaping[2] are those that neighborhood residents most prefer and are most conducive to better health. Keywords: mental fatigue, attention restoration theory, perceived restoration scale, commercial landscape quantity, public health, healthy urban environment [1] Refer to operational definitions (pages 4-6). [2] Refer to operational definitions (pages 4-6).
326

Vulnérabilité physique des milieux urbanisés face à la menace des inondations (lahars et crues éclair) : application au cas d'étude d'Arequipa au Pérou / The physical vulnerability of urban areas facing the threat of inundation from lahars and flash floods : application to the case study of Arequipa, Peru

Martelli, Kim 15 September 2011 (has links)
Les écoulements volcaniques (lahars, écoulements hyperconcentrés) et les crues soudaines représentent des phénomènes destructeurs et dangereux. Malgré leur pouvoir destructeur (e.g. Armero, Colombie, 1985), il existe très peu d’études centrées sur les effets des lahars en zone urbaine, alors qu’ils représentent une menace réelle pour de nombreuses villes, comme Arequipa, au Pérou. Arequipa est une ville de presque 1 million d’habitants située à 17 km au sud-est du volcan El Misti. La dernière éruption majeure du Misti remonte à 550 ans (1460 après J.C.) et de plus petites éruptions ont parsemé le 18ème et le 19ème siècle. Des lahars dont les volumes sont compris entre 0,01x106 et 11x106 m3 se sont formés et des inondations ont balayé les vallées tous les 5 à 10 ans. Suite à l’augmentation de la population d’Arequipa, la zone urbanisée s’étend maintenant sur les flancs du volcan, jusqu’à 9 km du sommet. En réponse à cette croissance rapide et apparemment incontrôlée, il est essentiel d’évaluer l’utilisation des sols, les bâtiments et les infrastructures en fonction de leur vulnérabilité. Des scénarios d’aléas ont été développés à partir d’anciennes et d’actuelles études géologiques, de cartes traditionnelles et des modèles numériques (tels que Titan2D) des dépôts volcaniques et fluviaux, d’études de terrain sur l’utilisation des sols, le type de bâtiments et d’infrastructures, d’analyses statistiques (y compris des analyses multi variantes) et enfin des caractéristiques géotechniques des matériaux utilisés pour les constructions. Trois scénarios de référence ont été utilisés allant d’un scénario de crue (récurrence de 5 à 10 ans) à une éruption (sub) Plinienne (VEI >3, récurrence de 5000 à 20 000 ans). Les zones inondables ont été délimitées en utilisant des résultats de code de simulation couplés à des cartographies géologiques et à des analyses de magnitude/fréquence. L'amélioration d'un MNT, construit à partir d’études DGPS et de données ASTER (10 m de résolution), a permis de modéliser les écoulements à partir de Titan2D. Les résultats du modèle montrent une extension des écoulements plus longue que celles proposées dans les études précédentes (e.g Vargas et al, 2010). L’étude de terrain a permis de classifier l’utilisation des sols selon 19 catégories et les principaux bâtiments et infrastructures selon 10 catégories. Par exemple, les bâtiments ont été classés et ordonnés selon des critères de nature du matériau principal les constituant, nombre d’étages, etc. De la même manière, la classification de l’utilisation des sols et du type d’infrastructures ont été classé en fonction de différents éléments comme le taux d’occupation, l’importance des évacuations d’urgence etc. Les effets mécaniques des écoulements sur les immeubles et les infrastructures ont été recherchés dans le but d’élaborer des fonctions de vulnérabilité. Cette étude a révélé que les bâtiments et l’utilisation des sols du Quebrada Huarangal sont particulièrement vulnérables et exposés au risque même lors d’un écoulement de faible magnitude. Ceci est essentiellement dû à la très faible qualité des constructions dans les zones à hauts risques du Quebrada Huarangal. Au contraire, le risque présent dans la vallée du Rio Chili est une zone à faible risque. Le niveau de risque inhérent au système d’énergie hydroélectrique et aux réserves d’eau potable reste inquiétant pour la ville, notamment durant une crise volcanique. Cette étude a mis en évidence les capacités d’intégration des données SIG générant de l’information sur le risque via la combinaison de scénarios d’aléas et d’éléments de vulnérabilité. Ces méthodes semblent être prometteuses pour l’étude et la prévention des risques volcaniques. De plus, une base de données mise à jour pourrait aider à gérer de manière efficace une possible crise volcanique en temps réel, et ce qui est plus important encore, assister les tâches de réduction des risques. / Volcanic mass flows (lahars, hyperconcentrated flows) and flash floods represent destructive and dangerous phenomena. Given evidence concerning the destructive nature of lahars (e.g. Armero, Colombia, 1985) there appears to be a lack of studies into the effect of lahars in dense urban environments ; a very real threat for many cities worldwide including the Arequipa, Peru. Arequipa, with nearly 1 million inhabitants, is located 17 km SW of El Misti Volcano. El Misti's last major eruption occurred 550 years ago (1460AD), with smaller eruptions occurring in the 18 and 19th Centuries. Lahars with volumes ranging from 0.01x106 m3 to 11x106 m3 have occurred, and flash floods have swept down valleys every 5 to 10 years. Population growth has resulted in urban sprawl to within 9 km of El Misti’s summit. It is this rapid and seemingly uncontrolled expansion which warrants the assessment of building, land use and infrastructure within a vulnerability framework. Hazard scenarios were developed from former and current geological studies ; conventional and computer-aided (e.g. Titan2D numerical modelling) mapping of volcaniclastic and fluvial deposits ; field surveys of land use, buildings and infrastructure ; statistical analysis (including multivariate analysis) ; and geotechnical characteristics of building materials. Three reference scenarios were used from a flash flood scenario (recurrence interval of 5 to 10 years) to a (sub)Plinian eruption (VEI >3, recurrence interval of 5000 to 20,000 years). Inundation zones were defined using simulation code results coupled with geological mapping and magnitude/frequency analysis. The results of Titan2D modelling feature a longer flow runout than in previous studies (e.g. Vargas et al., 2010) due to the creation of an enhanced 10 m DEM, constructed from DGPS surveys and ASTER data. Land-use, building and infrastructure surveys identified nineteen different land-use patterns, ten main building types and many key infrastructures. Building types were classified and ranked according to a number of components, such as the dominant building material, number of floors etc. Similarly land use and infrastructure were ranked according to a number of different elements such as occupancy rate, emergency importance etc. The mechanical effects of the flows on buildings and infrastructure were then investigated to elaborate vulnerability functions. The vulnerability and risk assessment have indicated that building, land use and infrastructure on the Quebrada Huarangal fan are particularly vulnerable and at risk even during the smallest magnitude flow. This is primarily due to very poor quality construction in high hazard areas on the Quebrada Huarangal fan. In contrast the risk posed in the Río Chili Valley is in general much less. The level of risk posed to the hydroelectric power scheme and the potable water supply is concern for the city, especially during a volcanic crisis. Data integration abilities of GIS in generating risk information by combining hazard scenarios with vulnerability elements have been highlighted in this research and offer promising prospects in the field of volcanic risk assessment and management. In addition, an updated database could help to efficiently handle possible volcanic crisis in real-time, and more importantly assist the risk reduction tasks.
327

Integrering av vertikala växtväggar i stadsmiljö : En studie för att stärka stadens ekosystemtjänster / Integration of vertical vegetation in an urban environment : A study to strengthen the city´s ecosystem services

Ståhl, Isabella, Ståhl, Rebecka January 2021 (has links)
Syfte: För att skapa väl fungerade städer som främjar mångfaldigt liv påstår C/O City (2017) att ekosystemtjänster måste implementeras. En ökad befolkning och förtätning har lett till bristande grönstruktur i urbana miljöer. Detta påverkar miljön och social-ekologin negativt. För att skapa hållbara, resilienta och attraktiva städer måste mångfunktionella gröna lösningar skapas och bidra med ekosystemtjänster. Målet med arbetet är därför att tillföra mer kunskap om stadens ekosystemtjänster och hur vertikala växtväggar kan förbättrar stadsmiljön. Metod: Den kvalitativa datan som analyseras i denna undersökning utgörs av intervjuer, enkäter, en dokument- och litteraturstudie. Intervjuerna används för att ge en djupgående förståelse för kommuners och byggherrars arbete med vertikala växtväggar samt ekosystemtjänster. Enkätundersökningen används för att översiktligt kartlägga kommuners arbete med vertikala växtväggar. I dokument- och litteraturstudien studeras verkliga exempel och hur de har utförts. Resultat: Vertikala växtväggar har möjligheten att stärka den urbana miljön i staden. Dessa gröna väggar kan bidra med stödjande-, reglerande-, kulturella- och försörjande ekosystemtjänster. I nuläget kan vertikala växtväggar påverka och förbättra mikroklimatet, besmycka hårda miljöer och till viss del stärka den biologiska mångfalden. För att motivera en storskalig etablering måste priset för levande väggar minskas och först då skulle en förbättring av stadsmiljön kunna ske. Konsekvenser: I många fall överskrider kostnaden incitamentet för etablering av levande väggar. Det presenteras en större vilja att stärka stadens horisontella grönstruktur och befintlig parkmark. I dagsläget ger växtväggarna främst ekosystemtjänster i ett mikroperspektiv.  Det behövs en storskalig etablering för att påverka staden och befolkningen i sin helhet. I framtiden kan arbetsprocessen förbättras genom att öka kommunikationen mellan aktörer, ställa krav på grönytefaktorn samt motivera både byggherrar och individen att prioritera ekosystemtjänster högre. Rapporten ska sprida ljus över problemet och främja förbättring. Med rapporten som underlag kan förbättring av kommuners arbetsprocess ske. Begränsningar: Studien utreder inte hur vertikala växtväggar är konstruerade, tekniken bakom dem, ekonomiska faktorer eller växtväggar konstruerade inomhus. Den insamlade empirin tyder däremot på att ekonomi har en betydelse i frågan. Urvalet för enkätundersökningen har begränsats till Sveriges 50 största kommuner, utifrån invånare. Trots att urvalet begränsats geografiskt anses resultatet vara generellt. Den insamlade empirin tyder på att åsikterna kring ämnet är samstämmiga, och kan därav spegla de generella åsikterna om vertikal växtlighet i Sverige. / Purpose: To create well-functioning cities that promote diversity of life C/O City (2017) claims that ecosystem services must be implemented. An increased population and urbanization have led to a lack of green areas in urban environments. This has a negative effect on the environment and social ecology. To create sustainable, resilient and attractive cities, multifunctional green solutions must be implemented and contribute to ecosystem services. The aim of the thesis is therefore to give more knowledge about the city's ecosystem services and how vertical vegetation can improve the urban environment.  Method: The qualitative data analyzed in this thesis consists of interviews, survey, a document- and literature study. The interviews are used to provide an in-depth understanding of municipalities and developers work with vertical vegetation as well ecosystem services. The survey is used to map municipalities work with vertical vegetation. The document- and literature study analyzes real examples and how they have been executed. Findings: Vertical vegetation have the potential to strengthen the urban environment in the city. These green walls can provide supporting, regulatory, cultural and provisoning ecosystem services. At present, vertical vegetation can influence and improve the microclimate, embellish harsh environments and to some extent strengthen biodiversity. To justify a large-scale establishment, the price of living walls must be reduced and only then could an improvement of the urban environment take place. Implications: In many cases, the cost exceeds the incentive for establishing living walls. A greater willingness is presented to strengthen the city's horizontal green structure and existing parks. At present, vertical vegetation mainly provide ecosystem services in a micro perspective. A large-scale establishment is needed to influence the city and the population as a whole. In the future, the work process can be improved by increasing communication between actors, establish requirements for the green space factor and motivating both developers and the individual to give higher priority to ecosystem services. The thesis should shed light on the problem and promote improvement. With the thesis as a basis, the municipalities work process can be improved. Limitations: The thesis doesn’t investigate how vertical vegetation are constructed, the technology, economic factors or vertical vegetation constructed indoors. The collected empirical evidence, on the other hand, indicates that economics has a significance in the matter. The sample for the survey has been limited to Sweden's 50 largest municipalities, based on inhabitants. Although the selection is limited geographically, the result is considered to be general. The collected empirical evidence indicates that the views on the subject are consistent and may therefore reflect the general views on vertical vegetation in Sweden.
328

Etude phénoménologique du dépôt sec d’aérosols en milieu urbain : Influence des propriétés des surfaces, de la turbulence et des conditions météorologiques / Phenomenological study of aerosol dry deposition in urban area : surface properties, turbulence and local meteorology influences

Rouspard, Pierre 21 January 2013 (has links)
Actuellement, le dépôt sec d’aérosols en milieu urbain est peu connu du fait d’un manque de données.Ces connaissances sont pourtant indispensables pour comprendre les flux de polluants dans les villes et estimer l’exposition d’habitants à des rayonnements ionisants dans le cas d’aérosols radioactifs. Un apport de données permettrait en outre d’améliorer la modélisation du dépôt dans ce milieu. Une approche expérimentale originale est employée pour étudier le dépôt sec d’aérosols submicroniques sur des surfaces urbaines. L’association d’expérimentations en soufflerie et in situ et l’utilisation de traceurs permettent de mesurer des vitesses de dépôt sec et d’étudier les différents phénomènes physiques qui régissent ce dépôt en milieu urbain. Ces données sont associées à des conditions de météorologie et de turbulence quantifiées par des mesures. Cet ensemble permet de hiérarchiser l’influence des principaux phénomènes physiques pour chaque type d’expérimentation. Notamment,des phénomènes différents doivent être considérés prépondérants dans le cas d’expositions chroniques ou aigües des surfaces urbaines aux particules atmosphériques. / Aerosol dry deposition is not much known for urban areas due to the lack of data. Knowledge on this phenomenon is necessary to understand pollutant fluxes in cities and to estimate inhabitant exposition to ionizing radiation of radioactive aerosols. A data providing could enable to enhance dry deposition models for these areas. An original experimental approach is performed to study submicron aerosol dry deposition on urban surfaces. Wind tunnel coupled to in situ experiments give results to study different physical phenomen on governing dry deposition. Dry deposition velocities are measured using aerosol tracers. These data are associated to turbulent and meteorological measured conditions. This database permits to classify the principal physical phenomenon for each experiment type. Finally, different phenomenon must be considered for chronic and acute exposition of urban surfaces to atmospheric particles.
329

Radar "Around the corner" : détection et localisation de cibles masquées en milieu urbain / Around the corner radar : detection and localization of an NLOS target in urban environment

Thai, Khac Phuc Hung 14 December 2018 (has links)
Les applications des techniques radar au milieu urbain constituent un domaine émergent. Une des difficultés principales est liée à la complexité du milieu de propagation induit par les bâtiments présents dans la scène. En effet, la présence de ces bâtiments génère d’une part des zones d’ombre à l’intérieur desquelles une cible n’est pas en visibilité directe, et d’autre part de nombreux multi-trajets produits par les possibles réflexions et diffractions sur les surfaces environnantes. Ces multi-trajets sont souvent vus comme une gêne, limitant les capacités de détection en radar. Or ils peuvent aussi être exploités à l’avantage du radar afin de détecter et localiser des cibles situées dans les zones d’ombre (cible en NLOS). L’objectif de ce travail de thèse est donc la mise en place de méthodes de traitement du signal permettant la détection et la localisation d’une cible en NLOS en milieu urbain et l’application de ces techniques pour détecter et localiser une cible en NLOS à partir de signaux réels. Pour cela, nous avons proposé dans un premier temps deux solutions pour la détection et la localisation de la cible en exploitant les multi-trajets. Dans un deuxième temps, nous avons développé deux filtres particulaires pour pister une cible en milieu urbain en présence de multi-trajets. Ces algorithmes ont été appliqués aux données réelles issues d’une expérimentation et ont montré des résultats prometteurs : même avec une connaissance approximative de la géométrie de la scène, il a été possible de détecter, localiser et suivre une cible en exploitant uniquement l’information fournie par les retards des multi-trajets. / The applications of radar techniques to the urban environment constitute an emerging subject. One of the main difficulties is related to the complexity of the propagation environment induced by the buildings present in the scene. Indeed, the presence of these buildings generates on the one hand shadow areas within which a target is not in line of sight, and on the other hand, many multipaths produced by reflections and diffractions on the surrounding surfaces. Classically, these multipaths are often seen as an inconvenience, limiting radar detection capabilities. However, these multipaths can also be exploited to the advantage of the radar to detect and locate targets located in the shadow areas (target in NLOS). The objective of this thesis work is therefore to develop signal processing methods allowing the detection and localization of a target located in shadow areas in urban environment and to apply these techniques for detecting and locating a target in NLOS from realistic or even real signals. For this, we first proposed two solutions for detection and localization of a target by exploiting multipath information. In a second step, we developed two particle filters to track a target in urban environment in the presence of multipaths. These algorithms have been applied to real data and showed promising results: even with an approximate knowledge of the geometry of the scene, it has been possible to detect, locate and track a target by exploiting only the information on multipath delays.
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Co děti kreslí (nejen) na asfalt / What do children draw (not only ) on the asphalt

Hnyková, Michaela January 2013 (has links)
The topic of this thesis What do children draw (not only) on the asphalt is to explore a material potential of outside environment as a specific device for teaching art education. The first part defines the role of the arts in contemporary education system, sets out the main goals and points out specialties of the field. The next section deals with the observation of spontaneous creative expressions of children on non-traditional sourfaces, their place in the natural need for exploration, and playing as a means of understanding the world. Compares the difference of the creation in outdoor environments on unconventional surfaces and the classical indoor creation and deals with the potential use of this knowledge. Looks for possibilities which would enrich the teaching of art and offer teachers new inspiration. Finally, on the basis of my own interventions, verifies the applicability of theoretical findings and their possible application in teaching at primary schools.

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