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An improved working model at the daily activity center. : An improvement work and a qualitative study on the professional’s perception on motivating participants with high-functioning autism to attend daily activities. / Ett förbättrat arbetssätt på dagligverksamheten : Ett förbättringsarbete samt en kvalitativ studie om de professionellas uppfattning om att motivera deltagarna med högfungerande autism att delta på daglig verksamhet.Chebbet, Mercy January 2023 (has links)
An improved working model at the daily activity center. An improvement work and a qualitative study on the perception of professionals on motivating participants with high-functioning autism to attend daily activities. Despite daily activities efforts to contribute to personal development, through offering meaningful activities, attendance among participants with high-functioning autism is low as those who have been granted the decision do not fully attend. This increases the likelihood of social isolation. In the absence of evidence-based working methods, the improvement team tested whether modifying the ordinary model would increase participants' attendance. This was through incorporating a model called Step Out. Step Out’s five components focused on increasing participants' motivation, by the professionals seeing the big picture, actively creating trust, working with solution-focused methods, and using motivational interviews. Four participants with low attendance were selected to take part in the intervention. The improvement work was conducted at a daily activity center in a small city in Sothern Sweden. The improvement work aimed to understand why the attendance of participants was low and to increase participant attendance through Step Out. The study aimed to gain an understanding of the professionals' perception of working with Step Out in the improvement work. The study was conducted through a qualitative study with five individual interviews and where the self-determination theory formed the basis for the analysis of professionals' perceptions. The results indicate that the smart goal to double the average attendance of the participants during the intervention was achieved in two participants but was not achieved in the other two participants. In addition, six reasons were shared by the participants on why they did not attend their daily activities. The professionals perceived that Step Out had given them new tools to strengthen the participant's autonomy, competence, and sense of belonging. Structural barriers were perceived as the greatest hindrance to the implementation of Step Out. In conclusion, participants are individuals with unique skills and interests, and professionals at the daily activity center must use an individualized approach. Keywords: low-attendance, motivation, self-determination theory, Step Out / Ett förbättrat arbetssätt på dagligverksamheten. Ett förbättringsarbete samt en kvalitativ studie om de professionellas uppfattning om att motivera deltagarna med högfungerande autism att delta på daglig verksamhet. Trots Daglig verksamhets goda intentioner att bidra till personlig utveckling och främja delaktighet i samhället genom att erbjuda meningsfull sysselsättning, är närvaron bland deltagarna med högfungerande autism låg eftersom de som beviljats insatser inte deltar fullt ut. Detta ökar risken för social isolering. I brist på evidens-baserade arbetsmetoder testade förbättringsteamet att modifiera den ordinarie arbetsmodellen genom att införliva en modell som heter Kliv Ut. Kliv Ut bestod av fem delar vars fokus låg på att öka deltagarnas motivation. Detta till dels genom att personalen skaffade sig en mer komplett bild av deltagaren, delvist genom ett aktivt skapande av initialt förtroende hos deltagarna, delvist lösningsfokuserade arbetsmetoder samt motiverande samtal. Fyra deltagarna med låg närvaro valdes ut för att delta i interventionen. Förbättringsarbetet genomfördes på en dagligverksamhet i en mindre stad i södra Sverige. Syftet med förbättringsarbetet var att förstå varför deltagarnas närvaro var låg och att öka närvaron med modellen Kliv Ut. Syftet med studien var att förstå de professionellas uppfattningar om att arbeta med Kliv Ut under förbättringsarbetet. Studien genomfördes genom en kvalitativstudie med fem enskilda intervjuer där självbestämmande teori utgjorde underlag för analys av de professionellas uppfattningar av Kliv Ut. Resultaten visade att SMART-målet att fördubbla deltagarnas genomsnittliga närvaro under interventionsperioden uppnåddes för två av deltagarna men inte hos två. Dessutom identifierades sex grundläggande orsaker till att deltagarna inte deltog i sina dagliga aktiviteter. De professionella uppfattade att Kliv Ut hade gett dem nya verktyg att stärka deltagarnas autonomi, kompetens och tillhörighet. Strukturella barriär identifierades av de professionella som det största hindret att genomföra Kliv Ut. Sammanfattningsvis betraktas deltagarna som individer med unika färdigheter och personliga intressen varför de som arbetar på dagligverksamheten behöver använda ett genomgående individanpassat tillvägagångssätt. Nyckelord: låg närvaro, motivation, självbestämmande teori, kliv ut
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Interactions between water-bodies and atmosphere at regional to global scalesEkhtiari, Nikoo 10 October 2019 (has links)
Ziel dieser Dissertation ist es, mithilfe zweier Herangehensweisen, das Verständnis der Zusammenhänge verschiedener physikalischer Prozesse des Klimasystems zu verbessern.
Im ersten Teil verwende ich Klimanetzwerke zu die gemeinsame Abhängigkeit von Meeresoberflächentemperaturen (SSTs) und Niederschlägen in Hinsicht auf globale charakteristiken und räumlichen Muster untersuchen. In diesem Kontext ist die El Niño Southern Oscillation (ENSO) das wichtigste Phänomen, welches großskalig SSTs und Niederschläge beeinflusst. Durch meine Analyse decke ich kurz und weitreichende Verbindungen auf und zeige deren Abhängigkeit von der jeweiligen ENSO-Phase (El Nino, La Nina, neutrale Phase). Darüber hinaus werden durch die Kombination einer diskreten Wavelet-Transformation mit dem Konzept der gekoppelten Klimanetzwerkanalyse die skalenspezifischen Verbindungen aufgelöst, die bei der ursprünglichen Auflösung der Daten oft übersehen werden.
Im zweiten Teil der Arbeit verwende ich Simulationen des COnsortium for Small scale MOdeling (COSMO) Climate Limited-area Modell (CCLM) und untersuche die Auswirkungen des Sobradinho-Stausees.
In dieser Arbeit benutzen ich das Flake Modell, um das vertikale Temperaturprofil des Sees zu bestimmen. Durch die Einbettung des Flake Modells in das CCLM konnte ich den Sobradinho-Stausee untersuchen. Dabei simuliere ich zwei verschiedene Szenarien. Die Simulationsergebnisse verifiziere ich mithilfe meteorologischer Daten von Oberflächen- und Satellitenmessungen. Die Ergebnisse zeigen, dass der See sowohl die bodennahe Temperatur als auch Wind- und Luftfeuchtigkeitsmuster der Umgebung beeinflusst. Zudem wird die Luftfeuchtigkeit durch den See erhöht und bewirkt Seewinde. Die Effekte des Sees auf die Luftfeuchtigkeit und temperaturen beschränken sich nicht nur auf die Nähe des Sees, sondern auch auf relativ weit entfernte Gebiete. / This dissertation aims at improving our understanding of the mechanisms of interactions between physical processes within the climate system via two different approaches.
In the first part, I have utilized climate networks to understand the mutual interdependence between sea surface temperatures (SST) and precipitation (PCP) in terms of global characteristics and spatial patterns. In this context, the globally most relevant phenomenon is the El Niño Southern Oscillation (ENSO), which strongly affects large-scale SST variability as well as PCP patterns all around the globe. My analysis uncovers both local and remote statistical connections and demonstrates their dependence on the current ENSO phase (El Niño, La Niña or neutral phase). Furthermore by combining time-scale decomposition by means of a discrete wavelet transform with the concept of coupled climate network analysis unravel the scale-specific connections that are often overlooked at the original resolution of the data.
In the second part of this thesis, I have focused on simulations with the COnsortium for Small scale MOdeling (COSMO) Climate Limited-area Model (CCLM) and investigate the effects of Lake Sobradinho, a large reservoir in Northeastern Brazil, on the local near-surface atmospheric and boundary layer conditions. In this thesis, the FLake model (Freshwater Lake model) is applied for obtaining the lake’s vertical temperature profile. I have simulated two alternative scenarios. The performance of the simulation is compared with data from surface meteorological stations as well as satellite data. The obtained results demonstrate that the lake affects the near-surface air temperature of the surrounding area as well as its humidity and wind patterns. Moreover, the humidity is significantly increased as a result of the lake’s presence and causes a lake breeze. The observed effects on humidity and air temperature also extend over areas relatively far away from
the lake.
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Central Asian Security: With a Focus on KazakhstanBragg, Marcus 01 May 2014 (has links)
This work focuses on the influence of terror, extremism, trafficking and corruption on the regional security of Central Asia, with a particular emphasis on Kazakhstan. Kazakhstan is regarded as the most stable and financially developed state in Central Asia, yet domestic and regional stability are threatened by the rise in extremism, narcotics trafficking, institutional corruption and acts of terrorism. The challenges of trafficking and extremism within the region originated from outside of Central Asia. Foreign organizations and ideologies are significant actors in progression of regional instability. Government response to these challenges can perpetuate or stymie the aforementioned threats to regional security. Repressive regimes inadvertently contribute to the propaganda of the non-state foes. A prominent solution is the international program referred to as border management. This program aims to support border security while also promoting economic growth and ensuring the protection of human rights. Improved borders promotes regional security, economic growth can potentially undermine the growth of corruption and human rights protection can undermine a large part of extremist propaganda.
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Ultrasonic testing of components produced with additive manufacturing : Towards improved detection and classification of defects / Ultraljudsprovning av komponenter tillverkade med additiva metoder : Mot förbättrad detektering och klassificering av defekterSahl, Mikael January 2024 (has links)
The focus in this work is on the use of ultrasonic testing as a method for inspecting components manufactured through additive manufacturing (AM) processes. The research is rooted in the need for effective non-destructive testingtechniques that can adapt to the unique challenges posed by AM-produced materials, including complex defect geometries and surface conditions. Ultrasonic testing is a versatile form of non-destructive testing, offering theability to detect internal flaws, such as voids, cracks, and inclusions, with highprecision and in real-time. Unlike many competing methods, ultrasonic testing works on most types of materials. Ultrasonic testing has been applied forinspection purposes for a long time. Now with emerging manufacturing methods, there is a need for evaluation techniques to keep up with this development.New data processing algorithms open up possibilities of extracting more information from the acquired signal. The thesis provides a review of UT’s capabilities in detecting and classifyingdefects within AM components, with a particular emphasis on the subtletiesintroduced by the layer-by-layer construction method inherent to AM technologies. The work advances development and validation of simulation modelsaimed at predicting the ultrasonic response from manufactured defects. Thesemodels are crucial for understanding the interaction between ultrasound wavesand material anomalies, offering insights into the potential for enhanced defectdetection strategies. The research also explores the practical case of integrating UT into the quality assurance processes by relying on mathematical simulation rather than experimental data. The findings suggest avenues for the refinement of creation of inspection procedure, including the the use of meta-models to cheaply acquire worst-case scenario defects, to better accommodate the specificities of AM materials. / Den här avhandlingen handlar om ultraljudsprovning av additivt tillverkade metalkomponenter. Ultraljud är en av flera metoder som används för att detektera defekter i komponenter utan att förstöra komponenten i processen. Samlingsnamnet för dessa metoder är oförstörande provning. Oförstörande provning är en viktig pusselbit i samhällets säkerhet då det möjliggör identifiering och utvärdering av potentiella defekter i material, vilket förebygger olyckor och strukturella fel. Vidare är det en viktig del inom hållbar utveckling genom att maximera nyttjandet av komponenter då dessa inte behöver ersättas med ett överdrivet försiktigt underhållsintervall. Ultraljudsprovning fungerar genomatt ultraljud introduceras in i en komponent, varefter en givare registrerar ekon som uppstår när ljudvågorna interagerar med eventuella defekter. Detta möjliggör både lokalisering och storleksbedömning av defekter, t.ex. sprickor, bindfel eller porer. Resultaten av den här avhandlingen syftar till att ge förutsättningar för att förbättra tolkningen av dessa signaler, dels genom att experimentellt validera simuleringsmodeller, samt tillämpning av dessa modeller för att utveckla en metamodell för att prediktera amplitudsvaret från en mängd defekter inom en viss parameterrymd. Med verktyg som detta kan billigare inspektionsprocedurer möjliggöras genom att man till större del kan förlita sig på simulering av signaler snarare än att skaffa stort underlag med experimentell data. / <p>Paper A, B and C are not included in the eletronic version. Paper C is under submission.</p>
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Fritidshemslärares uppdrag : En kvalitativ studie om fritidshemslärares profession, status och undervisning / The mission of leisure center teachers : A qualitative study of leisure center teachers' profession, status and teachingHansson, Chris, Larsson, Hannes January 2024 (has links)
Syftet med detta forskningsinriktade arbete var att belysa hur fritidshemslärare beskriver sin profession, sitt uppdrag och deras status inom skolväsendet. Detta arbete tar sin utgångspunkt ur en kvalitativ metod i form av semistrukturerade gruppintervjuer där åtta respondenter från två olika skolor deltagit. Forskningens framtagna text utifrån intervjuerna har kategoriserats med hjälp av tematisk analysmodell, för att hitta mönster i respondenternas svar där samtliga framtagna kategorier färgkodats. Kategorierna som framkommit har sedan analyserats mot analysbegreppen social jämförelse och in- och ut-grupper, då tidigare forskning visat på klyftor mellan fritidshemslärare och klasslärare, där en upplevd statusskillnad framhävs som bidragande orsak i kombination med bristande förståelse för varandras uppdrag. Studiens resultat synliggör flera brister, både vad gäller förståelsen för uppdraget, förutsättningar för att arbeta kvalitativt i kombination med en haltande samverkan som styrs av den statusskillnad som vi fått fram i vårt resultat. Resultaten indikerar även på en vision och vädjan om en bredare samverkan över gränserna mellan fritidshemslärare och klasslärare för att höja kvaliteten och arbeta främjande för en förståelse för varandras uppdrag, med en jämlik status mellan professionerna som utgångspunkt. Våra resultat indikerar att de statusskillnader som idag råder, härstammar från en profession som omfattar en otydlighet i uppdraget, där statusen blir signifikant och avgörande, vilket härleder frågan till det organisatoriska ledarskapet inom skolväsendet. I denna studie benämner vid lärare i fritidshem som fritidshemslärare.
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LHCb Upstream Tracker box : Thermal studies and conceptual designMårtensson, Oskar January 2016 (has links)
The LHC (Large Hadron Collider) will have a long shut down in the years of 2019 and 2020, referred to as LS2. During this stop the LHC injector complex will be upgraded to increase the luminosities, which will be the first step of the high luminosity LHC program (which will be realized during LS3 that takes place in 2024-2026). The LHCb experiment, whose main purpose is to study the CP-violation, will during this long stop be upgraded in order to withstand a higher radiation dose, and to be able to read out the detector at a rate of 40MHz,compared to 1MHz at present. This change will improve the trigger efficiency significantly. One of the LHCb sub-detectors the Trigger Tracker (TT), will be replaced by a new sub-detector called UT. This report presents the early stage design (preparation for mock-up building) of the box that will be isolating the new UT detector from the surroundings and to ensure optimal detector operation. Methods to fulfill requirements such as light and gas tightness, Faraday-cage behavior and condensation free temperatures, without breaking the fragile beryllium beam pipe, are established. / LHC (Large Hadron Collider) kommer under åren 2019-2020 att ha ett längre driftstopp. Under detta driftstopp så kommer LHC's injektionsanordningar att uppgraderas för att kunna sätta fler protoner i circulation i LHC, och därmed öka antalet partikelkollisioner per tidsenhet. Denna uppgradering kommer att vara första steget i "High Luminocity LHC"-programmet som kommer att realiseras år 2024-2026. LHCb-experimentet, vars främsta syfte är att studera CP-brott, kommer också att uppgraderas under stoppet 2019-2020. Framför allt så ska avläsningsfrekvensen ökas från dagens 1MHz till 40MHz, och experimentet ska förberedas för de högre strålningsdoser som kommer att bli aktuella efter stoppet 2024-2026. En av LHCb's deldetektorer, TT detektorn, kommer att bytas ut mot en ny deldetektor som kallas UT. Den här rapporten presenterar den förberedande designen av den låda som ska isolera UT från dess omgivning och försäkra optimala förhållanden för detektorn. Kraven på den isolerande lådan och tillvägagångssätt för att uppfylla dessa krav presenteras. / LHCb, LS2 and LS3 Upgrade
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[pt] EM BUSCA DA COR LOCAL: OS MODOS DE VER E FAZER VER NAS OBRAS DE JOSÉ DE ALENCAR E EUCLIDES DA CUNHA / [en] IN THE SEARCH OF THE LOCAL COLOR: THE WAYS OF SEEING AND MAKE SEE IN THE WORKS OF JOSÉ DE ALENCAR AND EUCLIDES DA CUNHAEDUARDO WRIGHT CARDOSO 04 November 2016 (has links)
[pt] Recurso pictórico elaborado no século XVIII, a cor local amplia seu
escopo original relativo ao campo pictórico e passa a compor e regular a produção
textual de escritores, historiadores, literatos e viajantes. Seu emprego em suportes
textuais desenvolve e acentua a dimensão visual da narrativa e, portanto, pode ser
concebido como uma expressão moderna das antigas associações entre cor e
palavra, narrativa e pintura. O objetivo desta tese é, pois, investigar o emprego
da cor local em tipos discursivos diversos, notadamente nas obras de José de
Alencar e Euclides da Cunha, salientando a dimensão visual implícita ao recurso
narrativo. A fim de compreender o investimento narrativo na visualidade, é válido
recuperar, a partir da Antiguidade, os modos de ver e fazer ver que comportam
topoi como o ut pictura poesis e o ut pictura historia, construções como a
sunopsis e a enargeia, além de expedientes como, entre outros, a autópsia e a
écfrase. A cor local, eis a hipótese inicial desta tese, incorpora e expressa parte
destes modos e recursos e, portanto, é capaz de reproduzir e reelaborar, na época
moderna, o anseio visual por meio da narrativa. A pesquisa pelos modos de ver e
fazer ver requer, como temáticas relacionadas que perpassam este estudo, a
consideração do estatuto e da importância atribuída à visão e ao olhar como
elementos cognitivos e comprobatórios, além das relações entre sujeito e objeto na
constituição do conhecimento. As produções ficcional de Alencar e factual de
Euclides permitem, então, demonstrar tanto a amplitude do recurso narrativo,
empregado em tipos discursivos diversos, quanto as variações relacionadas ao seu
uso, ou seja, como a delimitação de uma determinada paisagem altera o conteúdo
da forma da cor local. / [en] Pictorial device designed in the eighteenth century, the local color has
expanded its original scope for the pictorial field and begins to compose the
production of historians, writers and travelers. Its use in textual media develops
and enhances the visual dimension of the narrative and can be considered as a
modern expression of the ancient associations between color and word, narrative
and painting. The purpose of this thesis is to investigate the use of local color in
different discursive types, especially in the works of José de Alencar and Euclides
da Cunha, stressing the implicit visual dimension to the narrative device. In order
to understand the narrative investment in visuality it is worthed to recover from
antiquity the ways of seeing and make see that includes topoi as the ut pictura
poesis and ut pictura historia, resources like sunopsis and enargeia, and
expedients as, among others, the autopsia and ekphrasis. The initial hypothesis of
this thesis is that the local color expresses these modes and features and therefore
is able to reproduce and redevelop, in modern times, the visual desire through
narrative. The search for ways of seeing and make see requires, as related themes
that pervade this study, the consideration of the status and the importance
attributed to the vision as a cognitive element and proving, beyond the relations
between subject and object in the constitution of knowledge. The fictional
writings of Alencar and factual writings of Euclides allow then to demonstrate
both the extent of the narrative device, employed in various discursive types, as
the variations related to its use, that is how the delimitation of a particular
landscape changes the contents of the form of the local color.
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A mobile high-precision gravimeter based on atom interferometrySchmidt, Malte 08 November 2011 (has links)
Im Jahr 1991 wurde erstmals die Interferenz von Atomen experimentell nachgewiesen. Seitdem wird dieses Phänomen in vielen Bereichen der Grundlagenforschung angewendet, unter anderem zur Bestimmung von Naturkonstanten mit bisher unerreichter Genauigkeit oder für Tests des Äquivalenzprinzips. Grundsätzlich können auch geophysikalische Vermessungen des Schwerefeldes der Erde von dieser neuen Technik profitieren, allerdings waren Atominterferometrie-Experimente aufgrund ihrer Komplexität bisher nur in Laboren möglich. Erst kürzlich wurde mit der Entwicklung mobiler Atominterferometer begonnen, die nun die hochpräzise Messung von Rotationen, Gravitationsgradienten sowie der absoluten Schwerebeschleunigung außerhalb von Laboren ermöglichen. Im Rahmen dieser Arbeit wurde ein absolutes Gravimeter entwickelt, konstruiert und getestet. Es basiert auf Rb87-Atomen, die in einer Vakuumumgebung gefangen, gekühlt und senkrecht entgegen der Erdanziehung beschleunigt werden. Während des anschließenden freien Falls werden die atomaren Ensembles durch drei Raman Lichtpulse aufgespalten und rekombiniert. Die lokale Schwerebeschleunigung kann aus den resultierenden Interferenzmustern bestimmt werden, die abhängig von der Bewegung der Atome in einem Gravitationspotential sind. Wir haben den Wert der lokalen Schwerebeschleunigung, g, mit einer Auflösung von 1 : 10^10 bei einer Integrationszeit von 12 Stunden vermessen. Dies entspricht 2,2 * 10^-7 m/s^2/Sqrt(Hz). Mit dieser Genauigkeit konnten bereits zeitliche Veränderungen des lokalen Schwerefeldes registriert werden, hervorgerufen durch eine Vielzahl an Effekten wie Erd- und Ozeangezeiten oder atmosphärischen Variationen. In einem Vergleich unter ähnlichen Messbedingungen konnte unser Instrument die lokale Schwerebeschleunigung mit einer um fast eine Größenordnung höheren Genauigkeit bestimmen als ein herkömmliches Gravimeter. / Since 1991, matter wave interferometry has been used in many laboratories for a variety of fundamental physics experiments, e.g. measurement of the fine-structure and gravity constants or equivalence principle tests. This new technique is also ideally suited for high-accuracy geophysical gravity measurements. However, due to the complexity of these experiments they were so far confined to laboratory environments. Only in recent years efforts have been undertaken to develop mobile atom interferometers. These new sensors now open up the possibility to perform on-site high-precision measurements of rotations, gravity gradients as well as absolute accelerations. This work reports on the design, construction and first tests of an absolute gravimeter. It is based on interfering ensembles of laser cooled Rb87 atoms in a one meter high atomic fountain configuration. Local gravity is measured by applying three Raman light pulses while the atoms are in free fall, thereby splitting and recombining the atomic wave packets. The resulting interference fringes are sensitive to the movement of the atoms within a gravitational potential. We have measured the value of local gravity g at a resolution of one part in 10^10 at an integration time of 12 hours, or 2.2 * 10^-7 m/s^2/Sqrt(Hz). This was high enough to be sensitive to a number of time varying gravity effects like tides, ocean loading or changes in gravity caused by air pressure. In a comparison under similar measurement conditions, the instrument has surpassed the performance of conventional mobile gravimeters by almost one order of magnitude.
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Atom interferometry at geodetic observatoriesFreier, Christian 01 June 2017 (has links)
Das gravimetrische Atominterferometer (GAIN) ist ein transportables Atominterferometer welches spezifisch für hochpräzise Schweremessungen in der Geodäsie und Geophysik entwickelt wurde. Es basiert auf einer Rubidium Atomfontäne, stimulierten Ramanübergängen und einer 3-Puls Mach-Zehnder Interferometriesequenz. Die vorliegende Arbeit beschäftigt sich mit der Optimierung und Anwendung von GAIN als transportables Gravimeter für Absolutschweremessungen an geodätischen Observatorien welche über den aktuellen Stand der Technik hinaus gehen. Dabei wurden eine Absolutgenauigkiet von 29 nm/s^2, eine Langzeitstabilität von 0.4 nm/s^2 sowie eine Sensitivität von 82 nm/s^2 in einer Sekunde erreicht. Die gemessene Genauigkeit und Langzeitstabilität stellen, nach dem Wissen des Authors, die bis heute besten publizierten Werte für ein transportablen Atominterferometer dar und repräsentieren einen bedeutenden Fortschritt im Bereich der Gravimetrie. Um dies zu erreichen wurden umfangreiche Verbesserungen am Gerät umgesetzt und eine ausführliche Analyse der systematischen Messabweichungen durchgeführt. Unter anderem wurden ein System zur Kompensation von Corioliskräften und Ausrichtungsfehlern, ein verbessertes Schwingungsisolationssystem zur nachträglichen Korrektur von Umgebungsvibrationen und eine magnetische Abschirmung instrumenteller Streufelder implementiert. Darüber hinaus wurden insgesamt vier Messkampagnen in Berlin, sowie an den geodätischen Observatorien in Wettzell, Deutschland und Onsala, Schweden durchgeführt, um GAIN mit anderen hochmodernen Absolut- und Relativgravimetern zu vergleichen. Der direkte Vergleich zwischen GAIN und anderen Gravimetern stellt den prinzipbedingten Vorteil der Atominterferometrie durch die Kombination aus Absolutgenauigkeit, Stabilität und Langzeitbetrieb klar hervor. Dies wurde in der Arbeit durch die um einen Faktor 2-5 verbesserte Kalibrierung des Skalenfaktor von zwei supraleitenden Gravimetern demonstriert. / The gravimetric atom interferometer (GAIN) is a transportable setup which was specifically designed to perform high-precision gravity measurements at sites of interest for geodesy or geophysics. It is based on a Rb atomic fountain, stimulated Raman transitions and a three-pulse Mach-Zehnder atom interferometry sequence. The presented work is concerned with the optimization and application of GAIN as a transportable gravimeter in order to perform gravity measurements beyond the state-of-the-art. An absolute accuracy of 29 nm/s^2, long-term stability of 0.4 nm/s^2 and short-term noise level as low as 82 nm/s^2 in one second was achieved. The obtained long-term stability and accuracy values are, to the knowledge of the author, the best published performance of any transportable atom interferometer to date and represent a significant advancement in the field of gravimetry. A comprehensive analysis of the systematic error budget was performed to improve the accuracy and stability of the measured gravity value. Several setup improvements were implemented to this end, including Coriolis force and alignment control systems, an improved vibration isolator with post-correction and magnetic shielding which reduces spurious coupling due to stray fields. Measurement campaigns were conducted in Berlin and at geodetic observatories in Wettzell, Germany, and Onsala, Sweden, in order to compare GAIN to other state-of-the-art absolute and relative gravimeters. The direct comparison of GAIN to other absolute and relative gravimeters shows the general advantage of atom interferometers due to their unique combination of absolute accuracy, stability and robust architecture enabling continuous measurements. This was demonstrated during the presented campaigns by the improvement of the scale factor calibration of two superconducting gravimeters by a factor 2 to 5 using GAIN data.
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Spatial analyses of precipitation climatology using Climate NetworksRheinwalt, Aljoscha 08 February 2016 (has links)
Im folgenden wird ein Verfahren dargestellt welches die Möglichkeit bietet komplexe räumliche Zusammenhänge zwischen Niederschlagsereignissen quantitativ in Klimanetzwerke zu fassen und diese auf vielfältige Arten und Weisen zu analysieren. In dem Maße wie synchronisiert Niederschlagsereignisse zwischen Raumpunkten auftreten, in dem Maße sind diese Raumpunkte in Event Synchronization Klimanetzwerken verbunden. Zum einen wird das bestehende Ähnlichkeitsmaß der Ereignissynchronisation verbessert und erweitert, und zum anderen werden verschiedene, zum Teil neue, statistische Methoden zur Netzwerkanalyse vorgestellt und erläutert. Klimanetzwerke sind räumlich eingebettete Netzwerke und die statistisch zu zeigende Abhängigkeit der Ähnlichkeit vom räumlichen Abstand führt zu einer vom Raum nicht unabängigen Netzwerkstruktur. Dies ist in einer Vielzahl von Fällen ein ungewünschter Effekt und es wird eine Methodik entwickelt wie dieser statistisch quantifiziert werden kann. Des weiteren werden zwei weitere neue Netzwerkstatistiken vorgestellt. Einerseits das neue Netzwerkmaß Directionality und andererseits eine Netzwerkreduktion welche Klimanetzwerke auf Klimanetzwerke mit weitreichenden Verbindungen reduziert. Dieser neue Ansatz steht gewissermaßen im Gegensatz zur klassischen Klimanetzwerkkonstruktion die vor allem zu kurzreichweitigen Verbindungen führt. Das neue Netzwerkmaß Directionality gibt für jeden Raumpunkt des Netzwerks eine dominante Raumrichtung der Netzwerkverbindungen an und kann dadurch z.B. für bestimmte Event Synchronization Klimanetzwerke Isochronen abbilden. / In the following an approach to the analysis of spatial structures of precipitation event synchronizations is presented. By estimating the synchronicity of precipitation events between points in space, a spatial similarity network is constructed. These Climate Networks can be analyzed statistically in various ways. However, the similarity measure Event Synchronization that will be presented, as well as the concept of Climate Networks, is more general. Climate Network precipitation analyses are done in the applications part in order to present improvements to existing methodologies, as well as novel ones. On one hand, the existing similarity measure Event Synchronization will be refined and extended to a weighted and continuous version, and on the other hand, new methods for statistical analyses of Climate Networks will be presented. Climate Networks are spatially embedded networks and the probability of a link between two nodes decreases with the distance between these nodes. In other words, Climate Network topologies depend on the spatial embedding. Often this effect is distracting and should be considered as a bias in Climate Network statistics. This thesis provides a methodology to estimate this bias and to correct network measures for it. Furthermore, two novel graph statistics are introduced. First, the novel network measure Directionality, and second, a network coarse-graining approach that reduces Climate Networks to Climate Networks of teleconnections, i.e., long-ranged interrelations. This new approach is in contrast to existing Climate Network construction schemes, since commonly most links are short. The novel network measure Directionality provides a dominant direction of links in the embedding space. For undirected Event Synchronization networks this measure is applied for the estimation of Isochrones, i.e., lines of synchronous event occurrences.
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