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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.
411

A PRESENÇA DO EXÉRCITO E DA AERONÁUTICA NA ORGANIZAÇÃO ESPACIAL DE SANTA MARIA-RS / THE PRESENCE OF ARMY AND AIR FORCES IN THE SPATIAL ORGANIZATION OF SANTA MARIA-RS

Machado, Márcia Kaipers 30 May 2008 (has links)
The present research show a carefully study about the military presence in the Municipality of Santa Maria, Rio Grande do Sul, since his origens until our days give special importance in the spatial organization of the comunity along the times, as well the military unities here situated in the portuguese and brasizilian geopolitcs during the Colonial, Imperial and Republicans times. The origins of the city of Santa Maria góes back to the diplomatic treaty agreement of Saint Ildefonso, Spain, 1777 and then started a presence militarys unities in the municipality and engagement in the military conflicts of the countries of the Rio of de la Plata that assured a very important Geo-strategicaly presence of Santa Maria in the south of Brazil. For this studies was fetched support in the Teoritical and Methodically based in the geo-historical method, that try to explain the origens and the spacial organization of a specific view in the present with the restrict, conditionals of the historical times that gives a historic and political context that gives origens to the formation of this town. In this view study aproaches the geopolitical, terrtory and borders context. As well the formation of the Rio Grande do Sul in the way to understand the military presence in the geographic space of Santa Maria. The armed forces presence in Santa Maria was due to a geopolitical determination, since its up coming through participation of the defense of the brasilian borders and armed conflitcts wit the neighbourn countries, as example of the Oribe and Rosas wars and the of Paraguay. In this one were engaged the natives of Santa Maria, soldiers of the Seventh Cavalry Infantary Regiment and the Mallets Regiment. Santa Maria is situated in the central área of Rio Grande do Sul state, from these unities the city became a very importnt strategic-military pole, that concentrates a major contigent of the Army ando Air Forces. The establishment of the Army and the Air Force in the city in the present as in the past had a great importance for the spacial building and urban expansion. The military personnel here based gave a big support for the economic life. With the support of the military forces personnel and their families gives forces to the business activity, schools and colleges, social life, hospitals and filantropic societies and medical care services. / A presente pesquisa apresenta um estudo sobre a presença militar no município de Santa Maria, Rio Grande do Sul, Brasil, desde sua origem até os dias atuais ressaltando a influência militar na organização espacial do município ao longo do tempo, bem como o envolvimento das unidades militares aqui estabelecidas na geopolítica portuguesa e brasileira durante os períodos Colonial, Imperial e Republicano. A origem da cidade de Santa Maria remonta ao acordo diplomático do Tratado de Santo Idelfonso de 1777 e a partir daí, a presença de unidades militares do município participaram nos conflitos militares com os países platinos, assegurando uma importância geoestratégica de Santa Maria no sul do Brasil. Para o estudo buscou-se apoio teórico-metodológico nos subsídios da geografia histórica, que procura explicar a origem e/ou organização espacial de uma dada paisagem do presente, através de seus condicionantes históricos, reportando ao contexto político e econômico que deu origem ao processo de formação do município. Nesta perspectiva, esta pesquisa abordou conceitos como geopolítica, território e fronteira, bem como o processo de formação territorial do Rio Grande do Sul, para se compreender a presença militar no atual espaço geográfico de Santa Maria. Verifica-se que a atual presença das forças armadas em Santa Maria, obedeceu a uma determinação geopolítica desde o seu surgimento, através de sua participação na defesa das fronteiras ao sul do Brasil e em conflitos armados com os países vizinhos do Prata como, por exemplo, a Guerra contra Oribe e Rosas e a Guerra do Paraguai. Nesta última, participaram os militares santa-marienses que formavam o 7º Corpo Provisório de Cavalaria da Guarda Nacional, assim como o Regimento Mallet. Situada no centro do RS, Santa Maria, a partir destas unidades, torna-se um importante pólo estratégico-militar que concentra um dos maiores contingentes operacionais do Exército e da Aeronáutica. O estabelecimento das áreas militares na cidade, tanto no passado como no presente, influenciam na organização espacial da mesma orientando a sua expansão urbana, assim como o contingente militar aqui estabelecido contribui para a manutenção da atividade econômica. Baseado no contingente de militares e seus familiares residentes na cidade, infere-se que a presença militar em Santa Maria movimenta outros setores como escolas do ensino básico, instituições de nível superior, clubes sociais e recreativos, instituições filantrópicas, hospitais e clínicas médicas, entre outros.
412

ZONEAMENTO E MAPEAMENTO GEOAMBIENTAL NO MUNICÍPIO DE SORRISO - MT / ZONING AND MAPPING GEOENVIRONMENTAL IN THE MUNICIPALITY OF SORRISO - MT

Cabral, Tiele Lopes 11 March 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The action of man over nature manifests itself in many forms depending on the means adopted for the constant search for elements that allow for their presence in nature. Thus, the present study aims, zoning and mapping Geoenvironmental in the municipality of Sorriso - MT, in order to diagnose and assess the constraints and capabilities of the landscape opposite the occupation. Based on this goal and linked to the topic of research, geoenvironmental mapping comes assist in the study area because it allows jointly analyze information for use and occupation of the land, from the interaction of thematic maps with the support of Geographical Information System (GIS ), depicting more broadly triggering the evolution and/or degradation in certain areas of the city. Methodologically, the work is centered on the literature survey, the readings of subjects related to the central theme of the proposed research being developed at the Masters and data extracted from the GIS and fieldwork. The relevance of this issue is due to the very rapidity of the advance of agriculture in the Midwest region of Brazil that brings numerous interventions in the Cerrado environments linked to farming practices in agribusiness scale. Thus, from the perspective of Geoenvironmental approach, the analysis of landscape elements and the impact of human practices on these permits to understand how to establish social relationships with the natural substrate as a stage, even assisting in the understanding of surface dynamics in the many forms of use and occupation of the physical environment, especially in relation to primary production sector, where we observe the form of management of agricultural soil . As main results, this work shows that the sectors of greatest weaknesses are concentrated in the Dissection systems with native vegetation (riparian and gallery) and dirty fields in Quartzipsamments Cambisols and Hydromorphic, comprising an area with higher slopes, where erosion may occur and inability to agricultural use, and on the top of the Dissected Parecis Plateau where agricultural practice inserted this system, bringing a string of environmental problems. The definition of geo-environmental characteristics is fundamental for the development project planning and management that should involve society. Furthermore, this study serves as a basis for work involving different themes on a larger scale to the Plateau dissected Parecis, contributing information of a region with limited studies in the state of Mato Grosso. / A ação do homem sobre a natureza se manifesta sob inúmeras formas conforme os meios adotados para a busca constante de elementos que possibilitam a sua presença nesta natureza. Sendo assim, o presente trabalho tem por objetivo, o mapeamento e zoneamento Geoambiental do município de Sorriso-MT, com a finalidade de diagnosticar e avaliar as restrições e aptidões da paisagem frente à ocupação. Baseado nesse objetivo e vinculado à temática da pesquisa, o mapeamento geoambiental vem auxiliar o estudo na área, pois permite analisar conjuntamente, informações de uso e ocupação da terra, a partir da interação de mapas temáticos com o apoio do Sistema de Informação Geográfica (SIG), retratando de forma mais abrangente o desencadeamento da evolução e/ou degradação em determinadas áreas do município. Metodologicamente, o trabalho está centralizado no levantamento bibliográfico, nas leituras de assuntos relacionados ao tema central da proposta de pesquisa que está sendo desenvolvida no mestrado e em dados extraídos do geoprocessamento e trabalho de campo. A relevância deste assunto se deve a própria rapidez do avanço da agricultura na região Centro-Oeste do Brasil que traz consigo inúmeras intervenções nos ambientes do Cerrado vinculadas as práticas agrícolas na escala do agronegócio. Dessa forma, na perspectiva da abordagem Geoambiental, a análise dos elementos da paisagem e a repercussão das práticas humana sobre estes possibilita entender como se estabelecem as relações sociais tendo como palco o substrato natural, auxiliando ainda, na compreensão da dinâmica superficial frente às diversas formas de uso e ocupação do meio físico, especialmente em relação ao setor produtivo primário, onde se encontra a forma de manejo do solo agrícola. Como resultados principais, o trabalho aponta que os setores de maiores fragilidades estão concentrados nos Sistemas de Dissecação com mata nativa (ciliares e galeria) e campos sujos em Neossolos Quartzarênicos, Cambissolos e Hidromórficos, que comporta uma área com maiores declividades, onde podem ocorrer erosão e impossibilidade de uso agrícola e, no Sistema de topo do Planalto Dissecado dos Parecis onde a prática agrícola esta inserida, trazendo uma sequencia de problemas ambientais. A definição das características geoambientais é fundamental para o desenvolvimento de projetos de planejamento e gestão que devem envolver a sociedade. Além disso, este estudo serve como base para trabalhos, envolvendo diferentes temáticas, em escala maior para o Planalto dissecado dos Parecis, contribuindo com informações de uma região que apresenta estudos limitados no estado de Mato Grosso.
413

Etude mécanique des déformations des chaînes plissées d'avant-pays et rôle des argiles roches-mères durant leur maturation / Mechanical study of the fold-and-thrust belts deformation and role of the source-rock during their maturation

Berthelon, Josselin 11 December 2015 (has links)
Dans cette thèse, les changements de propriétés mécaniques des argiles riches en matière organique sont étudiés afin d'en déduire si leur enfouissement peut déclencher l'écaillage tectonique. Ce travail multidisciplinaire s'organise selon trois axes : une étude de terrain, une étude en laboratoire et une étude de modélisation numérique. L'étude de coupes géologiques équilibrées à travers les chaînes plissées Méditérranéennes montre l'importance de l'interprétation mécanique pour les thématiques de restaurations et pour valider les scénarios d'évolution structurale. Sur les Posidonia Schist Albanais, une caractérisation en laboratoire et à haute résolution de la formation roche-mère permet d'observer l'évolution verticale des paramètres minéralogiques, géochimiques et mécaniques qui contrôle le comportement rhéologique des roches-mères. En utilisant les modèles de bassin TEMISFlow, j'analyse les conditions pour créer des surpressions au sein d'un niveau de décollement roche-mère localisé sous un chevauchement. Au travers de modélisations géo-mécaniques FLAMAR, j'étudie les conditions mécaniques nécessaires pour développer des géométries de plis idéales au sein d'une stratigraphie mécanique. Une hiérarchisation des paramètres qui permettent d'activer un décollement au sein d'une roche-mère intégrée dans une stratigraphie mécanique est proposée. Au travers d'une analyse couplant ces deux aspects géo-mécanique et hydro-mécanique, ce travail est une contribution à la recherche d'une loi de comportement rhéologique permettant de prendre en compte l'adoucissement mécanique thermo-dépendant des argiles et des roches-mères dans les modélisations géo-mécaniques. / In this thesis, changes in the mechanical properties of organic-rich shales, when they mature, are studied in order to deduce if burial may mechanically activate tectonic imbrication and control the folding style. This multidisciplinary work is organized according to three axes: a field study, a laboratory study and a thermo-mechanical modeling study. In the first part, the study balanced geological cross-sections through the Mediterranean fold-and-thrust belts shows the importance of the mechanical interpretation for structural restorations and to validate structural evolution scenarios. The Albanian Posidonia Schist laboratory characterization allows discussing the vertical evolution of mineralogical, geochemical and mechanical parameters in a source-rock formation that control the rheological behavior of source rocks. Both geological cases serve as input data for modeling designed to simulate the evolution of a source rock during its burial. Two aspects are examined: Using TEMISFlow Arctem basin models, I analyze the conditions necessary to create overpressure in a source-rock detachment located in the footwall of a thrust. Through geo-mechanical modeling, I study the mechanical conditions necessary to develop ideal fold geometries within a mechanical stratigraphy. A hierarchy of parameters to activate a detachment within source rocks embedded in a mechanical stratigraphy is thus proposed. Through an analysis of the coupling between these two aspects, geo-mechanical and hydro-mechanical, this thesis is a contribution to the search of a rheological law that takes into account the thermo-dependent softening of shale and source rocks in geo-mechanical modeling.
414

Wildfire Management in the Southside Region of Canada’s Montane Cordillera - A Systems Modelling Application on Firebreak Strategies

Kessels, Henricus January 2016 (has links)
There is growing recognition of the importance of preserving Canada’s forests. Canada’s 348 million hectares of forest land cover 35% of its land area, representing 9% of the world’s forests and 24% of the world’s boreal forests. As a renewable resource, forests offer significant environmental, economic and recreational benefits and innumerable services contributing to the quality of life. Canada has recently entered an era of increased frequency and severity of natural disasters. Ecosystems and communities especially in western Canada have recently undergone a trend of increasing pressures from natural disturbances. These disturbances include wildfires associated with increased fuel load levels from past fire suppression regimes and a widely spread infestation of the mountain pine beetle in addition to changes in weather patterns. Wildfire activity has reached extreme levels in many of the recent years. This thesis profiles an area of western Canada within the Montane Cordillera covering the Nechako Lakes Electoral District in central British Columbia and assesses its vulnerability to the specific hazard of wildfires caused by natural and man-made sources. The objectives of this research are to review, simulate and assess the impact of various fuel management strategies in a sub-section of the Nechako Lakes Electoral District called the Southside. Values at risk include private property and old growth forest in respectively timber supply areas, provincial parks, woodlots and community forests. Simulation results show that firebreaks are effective in significantly reducing the area burned in different parts of the landscape. The performance of different strategies shows large variation. Although this has not been investigated further, such variation has likely been caused by topographic aspects and the positioning of firebreaks in the landscape in relation to climatic parameters. These results can therefore not be extrapolated beyond the simulated area, but do give an indication of the performance variation that may be expected when similar firebreaks are applied elsewhere. The results also show that model performance of all firebreak strategies is heavily and fairly consistently influenced by weather stream parameters. Sensitivity analyses of weather stream parameters show that although the reduction in total area burned varies, the ranking between strategies in their overall performance is consistent regardless of the weather pattern. Combined dry, warm and windy weather conditions lead to a 3.44-fold increase in total area burned as compared to the scenario with average weather conditions. In favourable weather conditions represented by wet, cold and nearly windless conditions, the model shows an 85% reduction in total burned area as compared to the average scenario. These results illustrate the significant impact of uncontrollable variables on the overall result.
415

Communications and Methodologies in Crime Geography: Contemporary Approaches to Disseminating Criminal Incidence and Research

Ogden, Mitchell 01 December 2019 (has links)
Many tools exist to assist law enforcement agencies in mitigating criminal activity. For centuries, academics used statistics in the study of crime and criminals, and more recently, police departments make use of spatial statistics and geographic information systems in that pursuit. Clustering and hot spot methods of analysis are popular in this application for their relative simplicity of interpretation and ease of process. With recent advancements in geospatial technology, it is easier than ever to publicly share data through visual communication tools like web applications and dashboards. Sharing data and results of analyses boosts transparency and the public image of police agencies, an image important to maintaining public trust in law enforcement and active participation in community safety.
416

Extragenic Accumulation of RNA Polymerase II Enhances Transcription by RNA Polymerase III

Neugebauer, Karla M., Grishina, Inna, Bledau, Anita S., Listerman, Imke 25 November 2015 (has links)
Recent genomic data indicate that RNA polymerase II (Pol II) function extends beyond conventional transcription of primarily protein-coding genes. Among the five snRNAs required for pre-mRNA splicing, only the U6 snRNA is synthesized by RNA polymerase III (Pol III). Here we address the question of how Pol II coordinates the expression of spliceosome components, including U6. We used chromatin immunoprecipitation (ChIP) and high-resolution mapping by PCR to localize both Pol II and Pol III to snRNA gene regions. We report the surprising finding that Pol II is highly concentrated ∼300 bp upstream of all five active human U6 genes in vivo. The U6 snRNA, an essential component of the spliceosome, is synthesized by Pol III, whereas all other spliceosomal snRNAs are Pol II transcripts. Accordingly, U6 transcripts were terminated in a Pol III-specific manner, and Pol III localized to the transcribed gene regions. However, synthesis of both U6 and U2 snRNAs was α-amanitin-sensitive, indicating a requirement for Pol II activity in the expression of both snRNAs. Moreover, both Pol II and histone tail acetylation marks were lost from U6 promoters upon α-amanitin treatment. The results indicate that Pol II is concentrated at specific genomic regions from which it can regulate Pol III activity by a general mechanism. Consequently, Pol II coordinates expression of all RNA and protein components of the spliceosome.
417

Egenskap och precision av GNSS BeiDou, Navstar (GPS), GLONASS samt kombinationen av GPS/GLONASS

Mahdere, Yafet January 2021 (has links)
Eftersom att både GNSS GPS och GLONASS har många likheter så finns möjlighet att utnyttja systemen i kombination. Dock föreligger olikheter vilket gör att systemen inte är fullkomlig kompatibla med varandra. Diskrepans i koordinater och tidsram utgör ett stort hinder för att kombinera dessa system. Men lösningar för koordinatstransformering har tagits fram för att eliminera dessa divergenser (Roßbach, 2001) BeiDou GNSS system till skillnad från GNSS GPS/GLONASS är ett av det senaste etablerade navigationssystem, vilket ställer frågor för användare om systemets kvalitéer och brister. Denna studie behandlar väldigt översiktligt om hur BeiDou systemet tillkom och bakgrunden, karaktärer samt ambitionen som är framlagt för systemet. BeiDou som ursprungligen kallades för COMPASS hade inte samma ändamål som GLONASS och GPS att tillfredsställa sina användare med globalt navigationssystem, intentionen med systemet var mestadels för positioneringssystem som skulle användas regionalt och för militära ändamål, men med tiden ökade ambitionen hos tillverkaren och en ny plan alstrades. planen var att satsa på att bli en av världsledande positionering och navigationssystem, och det skulle etableras och utnyttjas världen över. GLONASS och NAVSTARs GPS vilka är stora konkurrenter av produktutveckling inom rymd teknologi, har framställt världens mest noggranna och effektiva satellitsystemen. Även om ändamålen för dessa systemen hade sin utgångspunkt för applikation inom det militära avseende, har de gjort tillgängliga för diverse civil användning. GNSS GPS/GLONASS kan i vissa fall visa brister på uppkopplingshastighet men också mätningsprecision vid användning på egen hand, detta p.g.a. att antalet synliga och uppnåbara satelliter är begränsande. Detta har gett upphov till vidare studier inom systemens karaktärer samt implementering av kombination GNSS GPS/GLONASS. Emedan både systemen tillsammans består av 48 satelliter, att hitta tillfredställande antal satelliter under alla omständigheter underlättas. Systemen innehöll implikationer i sina grundinställningar som försvårar tillämpning av dessa i kombination. Satelliterna skickar information om sina positioner på två olika metoder, PZ-90 för GLONASS och WGS-84 för GPS. Metoderna är väldigt lika varandra med skiljer sig någorlunda i sättet de utför sina beräkningar. Denna skiljaktighet skapades då systemen ej hade som avsikt att samarbeta och eventuellt integrera med varandra vilket gjorde att utvecklingen av båda GNSS gick isär. Detta innebär att transformation av satellitinformation är nödvändigt för att uppnå tillförlitliga lösningar, då GNSS ska sammanställas och användas integrerat.
418

Les meules rotatives de la fin de l'Âge du Fer au haut Moyen Âge entre la Seine et le Rhin / Rotary querns and millstones from the Late Iron Age to early Middle Age, between the rivers Seine and Rhine

Picavet, Paul 14 February 2019 (has links)
Les meules, pièces maîtresses et les mieux conservées des moulins, sont emblématiques des questions relatives à l’histoire de l’économie et des techniques.De l’économie, parce que l’analyse des roches meulières révèle une chaîne complexe de recherche des ressources, d’extraction, de mise en forme, de distribution et d’utilisation qui dépend d’une série de facteurs qui ne concernent pas seulement les meules mais peuvent s’appliquer à toutes sortes de productions artisanales répondant à des besoins primaires de subsistance.Des techniques, parce que l’amélioration des procédés de mouture est le fruit d’une transmission des savoir-faire techniques alliée à une recherche constante de la meilleure réponse possible à des besoins alimentaires qui eux-mêmes évoluent. Cette notion de progrès technique, que l’on observe à la fois sur le temps long (ici plus d’un millénaire) et à l’occasion de brèves transitions politico-culturelles (la conquête romaine de la Gaule puis les migrations germaniques), est à l’origine de profonds changements socio-économiques.Sur la base de travaux de terrain (prospections thématiques), d’analyses d’objets (les meules) et d’un tour d’horizon bibliographique, cette thèse présente une synthèse régionale sur un type de mobilier modeste mais structurant des sociétés et des économies anciennes. / Millstones, as the centerpieces and the best preserved elements of mills, are characteristic of the questions relating to the history of techniques and economics.Of economics, because analysis of the rocks from which they are made reveal a complex chain including their research, extraction, shaping, distribution and use. The factors on which this chain depends don’t only concern querns and millstones but can be applied to all types of craft production that answer to primary needs of subsistence.Of techniques because the improving of milling processes is due to a transmission of technical savoir-faire, mixed with a constant research for the best solution to evolving food needs. This notion of technical progress is observed both over a long time scale (1000 years) and during brief political and cultural transitions (the Roman conquest of Gaul, and the Germanic migrations). This evolution is the basis of deep social and economic changes.Based on field surveys, artifact analysis (querns and millstones) and a literature survey, this thesis presents a regional synthesis on a modest but structuring element of ancient societies and their economies.
419

Stabiliserande betongskiva med elastisk grundläggning på friktionsjord : En analys av rotationsstyvheter i friktionsjord / Stabilizing concrete wall with elastic foundation on friction soil : Analysis of the rotational stiffness of the soil

Holst Nywertz, Daniel, Livfors, Mattias January 2016 (has links)
Vid grundläggning av medelhöga hus på friktionsjord kan i många fall grundläggningen genomföras med betongfundament. I dessa fall är jordens kompressionsegenskaper av mycket stor betydelse. Jordars materialkurvor visar att elasticitetsmodulen för avlastning är större än den för pålastning. För ett momentbelastat fundament kommer ena sidan utsättas för pålastning och den andra för avlastning. Vanligen beräknas dock grundens rotationsstyvhet endast med hjälp av modulen för pålastning vilket leder till att rotationsstyvheten underskattas. Ytterligare antas även ofta att ett fundaments rotationsstyvhet kan beräknas med hjälp av jordens bäddmodul av centrisk last. Denna beräkning är baserad på en lastspridning i djupet och underskattar rotationsstyvheten jämfört med en beräkning baserad på plattans vinkeländring och tröghetsmoment. Denna underskattning beror på att spänningar i jorden avtar långsammare vid centrisk belastning än vid momentbelastning. En ökning av grundens rotationsstyvhet medför en ökning av byggnadens globala knäcklast. Momentbelastade fundament riskerar att lätta från marken då momentets dragspänningar når upp till normalspänningarna av byggnadens tyngd. Då fundamentet lättar från marken kan inte längre hela fundamentets yta utnyttjas. Risken för att detta sker kan minskas genom att använda sig av en platta med elastiskt mellanlägg i dess centrala delar I denna studie visas hur grundläggningens rotationsstyvhet förändras dels beroende på beräkningsmetod samt om hänsyn tas till skillnaden mellan jordens på- och avlastningsmodul. Det visas även hur rotationsstyvheten förändras beroende på hur stor skillnaden mellan på- och avlastningsmodul är. Rotationsstyvheter har framtagits för fem olika plattor varav två är kvadratiska och två rektangulära med konstant tjocklek samt en rektangulär med elastiskt mellanlägg. För att utföra studien har såväl handberäkning som finita element beräkningar genomförts. De mjukvaror som använts är Mathcad för handberäkningen samt Plaxis 2D och Ansys APDL för den finita element beräkningen. Den fullständiga analysen är dock genomförd i Ansys APDL  och Plaxis 2D har endast använts för att verifiera att den modell som skapats är tillförlitlig. Resultaten av denna studie visar att rotationsstyvheten blir mycket bättre om beräkningen baseras på plattans vinkeländring till följd av momentbelastning istället för den bäddmodul som avser fundamentets egenskaper vid centrisk belastning. Resultaten visar också att rotationsstyvheten blir bättre ju större avlastningsmodulen är i förhållande till pålastningsmodulen. Den finita elementberäkningen ger en ökning av rotationsstyvheten med en faktor 1.75 – 3.85 för det fall med en relativ styvhetsfaktor 4. Motsvarande handberäkning ger en ökning med en faktor 1.45 – 2.85. Resultaten visar också att rotationsstyvheten för en grundplatta som förses med elastiskt mellanlägg endast blir något lägre än motsvarande grundplatta utan elastiskt mellanlägg. Samtidigt visade sig grundplattan med elastiskt mellanlägg klara ett väsentligt högre moment innan den lättar från jordytan på avlastad sida av fundamentet. Resultaten från knäckningsberäkningen visar att antalet våningar för en byggnad grundlagt med betongfundament på friktionsjord kan höjas från 8 till som mest 12 för det fallet då en relativ styvhetsfaktor är 4 och då skivans längd är 8 meter. Antalet våningar för en stabiliserande skiva med längden 4 meter kan höjas som mest till 9. / When founding medium high buildings on friction soil, the foundation is often carried out as a concrete footing. In these cases the earth compression characteristics are of very great importance. The material curve for soils shows that the elastic modulus of unloading is greater than that of loading. In a moment-loaded foundation, one side will be subjected to loading and the other to unloading. The rotational stiffness is however usually calculated only based on the elastic modulus of loading which result in an underestimation of the rotational stiffness. The rotational stiffness is also often calculated based on the bedding modulus due to centric loading. This calculation is based on an increasing area of the stress distribution by the depth and is underestimating the rotational stiffness compared to a calculation based on the angular change of the slab and its moment of inertia. This underestimation is due to that the stresses caused by centric loading decreases less rapidly than those caused by moment loading. An increase of the foundations rotational stiffness leads to an increase of the buildings global buckling load. Moment-loaded foundations are likely to ease off the ground at high moments. This occurs when the tensile stress caused by the moment reaches the normal stress due to the building's weight. When the foundation is lifted from the ground, the entire foundation surface can no longer be utilized. The risk for this to occur can be reduced by using a slab with elastic inserts. In this thesis, it is shown how the rotational stiffness of the foundation changes depending on the calculation method as well as if the difference in loading and unloading modulus is taken into account. It is also shown how the rotational stiffness changes depending on the relation between the loading and unloading modulus. Rotational stiffness has been evaluated for five different slabs of which two are square and two rectangular with constant thickness and one rectangular with elastic inserts. In order to perform the study, both hand calculation as well as finite element calculations are carried out. The used software are Mathcad for the hand calculation and Plaxis 2D as well as Ansys APDL for the finite element calculation. The full analysis is, however, performed in Ansys APDL and Plaxis 2D has only been used to verify that the model created is reliable. The results shows that the rotational stiffness of the foundation with the elastic inserts only reduces a small amount compared with the corresponding foundation without elastic inserts. The results also shows that the foundation with the elastic inserts resists a substantially higher moment-load before it eases off the ground on the unloaded side of the foundation.
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A study on the use of ARKit toextract and geo-reference oorplans / En studie på användingen av ARKit för att extrahera och georeferera planlösningar

Larsson, Niklas, Runesson, Hampus January 2021 (has links)
Indoor positioning systems (IPS) has seen an increase in demand because of the needto locate users in environments where Global Navigation Satellite Systems (GNSS) lacksaccuracy. The current way of implementing an IPS is often tedious and time consuming.However, with the improvements of position estimation and object detection on phones,a lightweight and low-cost solution could become the standard for the implementationphase of an IPS. Apple recently included a Light Detection And Ranging (LiDAR) sensorin their phones, greatly improving the phones depth measurements and depth understanding.This allows for a more accurate virtual representation of an environment. This thesisstudies the accuracy of ARKit’s reconstructed world and how different environments impactthe accuracy. The thesis also investigates the use of reference points as a tool to map thereconstructed environment to a geo-referenced map, such as Google Maps and Open StreetMap. The results show that ARKit can create virtual representations with centimetre levelaccuracy for small to medium sized environments. For larger or vertical environments,such as corridors or staircases, ARKit’s SLAM algorithm no longer recognizes previouslyvisited areas, causing both duplicated virtual environments and large drift errors. With theuse of multiple reference points, we showed that ARKit can and should be considered asa viable tool for scanning and mapping small scale environments to geo-referenced floorplans.

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