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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.
751

Senja : Communal housing for tourists and seasonal workers in the fishing industry in the north of Norway / Senja : Kollektvit boende för turister och säsongsarbetare inom fiskeindustrin i Nord Norge

Eriksson, Anna January 2018 (has links)
This project takes place in the north of Norway, on an Island called Senja. With its beautiful nature and reliable resource of fish it attracts tourists in the summer time and seasonal workers in the fishing industry during the winter.  How can communal housing for tourists and workers act as a hub in the local community? Around this question a cluster of different functions has been developed that serves the whole community as well as the communal housing with private living units.
752

Resilience Through Form : A case study of Metro Boston, Exploring the Relationship of Urban Form & Extreme Heat / Resiliens Genom Form: : Fallstudie av metro Boston, utforskning av förhållandet mellan stadsform och extrem värme

Lewis, Gavin January 2019 (has links)
The severity of extreme heat events paired with the urban heat island effect cannot be overstated, as the impacts are substantial and widespread, affecting peak energy demands, transport systems, air and water quality, and most notably causing heat-related illnesses and death. These consequences make evident the importance of reducing heat in urban areas and ensuring that urban populations are safe during extreme heat events. In order to both reduce the urban heat island effect and prepare cities for a hotter future, it is critical to building our understanding of the cities at risk and the relationship between heat and the urban environment. This thesis applies urban morphology theory and remote sensing techniques to explore how urban typologies in Metro Boston perform during an extreme heat event. Included within the thesis is a literature review exploring urban heat methodologies and urban morphology, a desktop review examining a set of cities’ climate action reports, and a remote sensing-based analysis to determine the feasibility of uniting land surface temperature and public weather station data. The desktop review of cities determined that while each city has begun to implement numerous socially driven initiatives and large-scale green infrastructure plans, there is little work incorporating urban form within these strategies. Additionally, while the land surface temperature and weather station maps from the remote sensing analysis were deemed insufficient, several valuable questions and findings arose through the process. The case study analysis of Metro Boston identified three predominant urban forms in the study area and 12 sites were studied in relation to their heat performance in the morning, afternoon, and evening. The heat maps applied were developed through Heat Watch Report, a collaboration between the National Oceanic and Atmospheric Administration, the municipalities of Boston, Brookline, and Cambridge, and CAPA Strategies. The analysis revealed there is a universal change in temperature among all forms throughout the day, with peak temperatures occurring in the late afternoon period. The study also concluded that while temperature between forms was not significant, variation between sites of the same form was observed, with internal vegetation composition (NDVI) and neighboring landcover and urban form becoming key factors in increasing or reducing experienced heat. / Svårighetsgraden av extrema värmehändelser i kombination med stadens värmeöeffekt kan inte överskattas eftersom dessa effekter är betydande och utbredda, vilket påverkar energibehov, transportsystem, luft- och vattenkvalitet och framför allt orsakar värmerelaterade sjukdomar och dödsfall. Dessa konsekvenser visar tydligt vikten av att minska värmen i stadsområden samt se till att stadsbefolkningarna är säkra under extrema värmehändelser. För att både minska stadens värmeöeffekt och förbereda städer för en varmare framtid är det avgörande att fördjupa vår förståelse för städer i riskzon och förhållandet mellan värme och stadsmiljö.  Denna avhandling tillämpar urban morfologiteori och fjärranalys tekniker för att utforska hur urbana typologier i Metro Boston presterar under en extrem värmehändelse. I avhandlingen ingår en litteraturöversikt som utforskar stadsvärmemetoder och stadsmorfologi, en undersökning av en uppsättning av städers klimatinsatsrapporter och en fjärravkänningsbaserad analys för att undersöka genomförbarheten att förena markytstemperaturen och offentliga väderstationsdata. Undersökningen av stadsklimatrapporterna visade att även om varje stad har börjat genomföra många socialt drivna initiativ och storskaliga gröna infrastrukturplaner, finns det i dagsläget lite arbete kring integrerande av stadsform i dessa strategier. Även om markytstemperaturen och väderstationskartan från fjärranalysanalysen ansågs otillräckliga uppstod flera värdefulla frågor och fynd genom processen.  Fallstudieanalysen av Metro Boston identifierade tre dominerande urbana former i studieområdet och 12 platser studerades i förhållande till deras värmeprestanda på morgonen, eftermiddagen och kvällen. De värmekartor som tillämpades utvecklades genom Heat Watch Report, ett samarbete mellan National Oceanic and Atmospheric Administration, kommunerna Boston, Brookline och Cambridge och CAPA Strategies. Analysen avslöjade en universell temperaturförändring bland alla former under dagen, med topptemperaturer som inträffar under sen eftermiddagsperiod. Studien visar också att medan temperaturskillnaderna mellan formerna inte var signifikanta, observerades variation mellan platser med samma form, med intern vegetationssammansättning och angränsande marktäkning och urban form som nyckelfaktorer för en ökad eller minskad upplevd värme.
753

Spatiotemporal modeling of climate change impact on hydro-meteorological risk under a large ensemble d4pdf future warming scenarios:an implication for agriculture risk over Godavari River Basin, India / 時空間モデルを用いた気候変動予測と将来シナリオにおける水文気象学的リスクの評価~インドのGodavari川流域を対象として~

Bharambe, Khagendra Pralhad 24 September 2021 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第23497号 / 工博第4909号 / 新制||工||1767(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 清水 芳久, 教授 米田 稔, 准教授 松田 知成 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
754

Extreme Ultraviolet Spectral Streak Camera

Szilagyi, John Michael 01 January 2010 (has links)
The recent development of extreme ultraviolet (EUV) sources has increased the need for diagnostic tools, and has opened up a previously limited portion of the spectrum. With ultrafast laser systems and spectroscopy moving into shorter timescales and wavelengths, the need for nanosecond scale imaging of EUV is increasing. EUV’s high absorption has limited the number of imaging options due to the many atomic resonances in this spectrum. Currently EUV is imaged with photodiodes and X-ray CCDs. However photodiodes are limited in that they can only resolve intensity with respect to time and X-ray CCDs are limited to temporal resolution in the microsecond range. This work shows a novel approach to imaging EUV light over a nanosecond time scale, by using an EUV scintillator to convert EUV to visible light imaged by a conventional streak camera. A laser produced plasma, using a mass-limited tin based target, provided EUV light which was imaged by a grazing incidence flat field spectrometer onto a Ce:YAG scintillator. The EUV spectrum (5 nm-20 nm) provided by the spectrometer is filter by a zirconium filter and then converted by the scintillator to visible light (550 nm) which can then be imaged with conventional optics. Visible light was imaged by an electron image tube based streak camera. The streak camera converts the visible light image to an electron image using a photocathode, and sweeps the image across a recording medium. The streak camera also provides amplification and gating of the image by the means of a micro channel plate, within the image tube, to compensate for low EUV intensities. The system provides 42 ns streaked images of light with a iii temporal resolution of 440 ps at a repetition rate of 1 Hz. Upon calibration the EUV streak camera developed in this work will be used in future EUV development.
755

Extreme wave conditions and the impact on wave energy converters

Katsidoniotaki, Eirini January 2021 (has links)
The amount of energy enclosed in ocean waves has been classified as one of the most promising renewable energy sources. Nowadays, different wave energy conversion (WEC) systems are being investigated, but only a few concepts have been operated in a sea environment. One of the largest challenges is to guarantee the offshore survivability of the devices in extreme wave conditions. However, there are large uncertainties related to the prediction of extreme wave loads on WECs.  Highfidelity computational fluid dynamics (CFD) simulations can resolve nonlinear hydrodynamic effects associated with wave-structure interaction (WSI). This thesis explores the point-absorbing WEC developed by Uppsala University in extreme wave conditions. The dynamic response and the forces on key components (mooring line, buoy, generator's end-stop spring) of the device are studied and compared. The high nonlinear phenomena accompany the steep and high waves, i.e., breaking behavior, slamming loads can be well-captured by the highfidelity CFD simulations. A commonly used methodology for extreme waves selection, recommended by technical specifications and guidelines, is the environmental contour approach. The 100-year contour in Hamboldt Bay site in California and the 50-year contour in the Dowsing site, outside the UK, are utilized to extract the extreme waves examined in the present thesis. Popular methodologies and data from different sources (observational and hindcast data) are examined for the environmental contour generation providing useful insights. Moreover, two popular approaches for the numerical representation of the extreme sea states, either as focused wave or as equivalent regular wave, were examined and compared. A midfidelity model of the WEC is successfully verified, as the utilization of lower fidelity tools in the design stage would reduce the computational cost. Last but not least, in CFD simulations the computational grid is sensitive in large motions, something often occurs during extreme-WSI. The solution of this issue for the open source CFD software OpenFOAM is provided here.
756

Grenzen des Hörens: Harsh Noise Wall und die Metaphorik des Rauschens

Wallraf, David 24 October 2023 (has links)
Angesichts ihrer unüberschaubaren Ausdifferenzierung scheint es heute kaum noch möglich, eine allgemeingültige Definition von Musik zu finden. Ausgehend von diesem Problem nimmt dieser Text ihre Randbereiche in den Fokus: Die Grenzen des Hörens, wie sie in extremen Formen experimenteller Musik, etwa im Harsh Noise Wall, ausgelotet werden und die Grenzen des Vernehmens, wie sie sich im stets metaphorischen Sprechen über Musik abzeichnen. Als unüberschreitbare Grenze dieser beiden Randzonen bildet die Klangfarbe das Zentrum der Argumentation und den Abschluss der Überlegungen. / Today it seems nearly impossible to find a universally valid definition of music due to its vast differentiation. Ensuing from this problem, this text focuses on music’s borders: the hearing limits as they are explored in extreme forms of experimental music (like Harsh Noise Wall) and the margins of understanding as they are shown in the use of metaphors in speaking about music. Timbre is discussed as an uncrossable border of these two aspects. These thoughts form both the focus and the conclusion of this text.
757

Forecasting Volume of Sales During the Abnormal Time Period of COVID-19. An Investigation on How to Forecast, Where the Classical ARIMA Family of Models Fail / Estimering av försäljningsprognoser under den abnorma tidsperioden av coronapandemin

Ghawi, Christina January 2021 (has links)
During the COVID-19 pandemic, customer shopping habits have changed. Some industries experienced an abrupt shift during the pandemic outbreak while others navigate in new normal states. For some merchants, the highly-uncertain new phenomena of COVID-19 expresses as outliers in time series of volume of sales. As forecasting models tend to replicate past behavior of a series, outliers complicates the procedure of forecasting; the abnormal events tend to unreliably replicate in forecasts of the subsequent year(s). In this thesis, we investigate how to forecast volume of sales during the abnormal time period of COVID-19, where the classical ARIMA family of models produce unreliable forecasts. The research revolved around three time series exhibiting three types of outliers: a level shift, a transient change and an additive outlier. Upon detecting the time period of the abnormal behavior in each series, two experiments were carried out as attempts for increasing the predictive accuracy for the three extreme cases. The first experiment was related to imputing the abnormal data in the series and the second was related to using a combined model of a pre-pandemic and a post-abnormal forecast. The results of the experiments pointed at significant improvement of the mean absolute percentage error at significance level alpha=0.05 for the level shift when using a combined model compared to the pre-pandemic best-fit SARIMA model. Also, at significant improvement for the additive outlier when using a linear impute. For the transient change, the results pointed at no significant improvement in the predictive accuracy of the experimental models compared to the pre-pandemic best-fit SARIMA model. For the purpose of generalizing to large-scale conclusions of methods' superiority or feasibility for particular abnormal behaviors, empirical evaluations are required. The proposed experimental models were discussed in terms of reliability, validity and quality. By residual diagnostics, it was argued that the models were valid; however, that further improvements can be made. Also, it was argued that the models fulfilled desired attributes of simplicity, scaleability and flexibility. Due to the uncertain phenomena of the COVID-19 pandemic, it was suggested not to take the outputs as long-term reliable solutions. Rather, as temporary solutions requiring more frequent updating of forecasts. / Under coronapandemin har kundbeteenden och köpvanor förändrats. I vissa branscher upplevdes ett plötsligt skifte vid pandemiutbrottet och i andra navigerar handlare i nya normaltillstånd. För vissa handlare är förändringarna så pass distinkta att de yttrar sig som avvikelser i tidsserier över försäljningsvolym. Dessa avvikelser komplicerar prognosering. Då prognosmodeller tenderar att replikera tidsseriers tidigare beteenden, tenderas det avvikande beteendet att replikeras i försäljningsprognoser för nästkommande år. I detta examensarbete ämnar vi att undersöka tillvägagångssätt för att estimera försäljningsprognoser under den abnorma tidsperioden av COVID-19, då klassiska tidsseriemodeller felprognoserar. Detta arbete kretsade kring tre tidsserier som uttryckte tre avvikelsertyper: en nivåförskjutning, en övergående förändring och en additiv avvikelse. Efter att ha definierat en specifik tidsperiod relaterat till det abnorma beteendet i varje tidsserie, utfördes två experiment med syftet att öka den prediktiva noggrannheten för de tre extremfallen. Det första experimentet handlade om att ersätta den abnorma datan i varje serie och det andra experimentet handlade om att använda en kombinerad pronosmodell av två estimerade prognoser, en pre-pandemisk och en post-abnorm. Resultaten av experimenten pekade på signifikant förbättring av ett absolut procentuellt genomsnittsfel för nivåförskjutningen vid användande av den kombinerade modellen, i jämförelse med den pre-pandemiskt bäst passande SARIMA-modellen. Även, signifikant förbättring för den additiva avvikelsen vid ersättning av abnorm data till ett motsvarande linjärt polynom. För den övergående förändringen pekade resultaten inte på en signifikant förbättring vid användande av de experimentella modellerna. För att generalisera till storskaliga slutsatser giltiga för specifika avvikande beteenden krävs empirisk utvärdering. De föreslagna modellerna diskuterades utifrån tillförlitlighet, validitet och kvalitet. Modellerna uppfyllde önskvärda kvalitativa attribut såsom enkelhet, skalbarhet och flexibilitet. På grund av hög osäkerhet i den nuvarande abnorma tidsperioden av coronapandemin, föreslogs det att inte se prognoserna som långsiktigt pålitliga lösningar, utan snarare som tillfälliga tillvägagångssätt som regelbundet kräver om-prognosering.
758

Growth and Characterization of Diamonds for Use in High Pressure Sensing

Hamel, Michael Tokiyoshi 23 June 2022 (has links)
Diamond possesses unique physical properties which give it great potential as a solid state framework for quantum sensors. Despite a worldwide research and development effort, the primary factors limiting its wider implementation are the technical difficulties related to high quality synthesis and device manufacture. In this work, as a first objective, laboratory diamond synthesis is explored with the aim to achieve single crystal diamond of high quality. A suite of characterization methods is implemented to evaluate and understand the physical qualities of synthesized diamond. Through a measurement process, a procedure for improving diamond growth is presented. As a secondary objective, a diamond-based defect which can be functionalized as a quantum sensor is investigated. The negatively charged silicon vacancy defect (SiV⁻) in diamond is explored for its potential use as a quantum high pressure/low temperature sensor. This SiV⁻ defect is optically accessible by photoluminescence. This optical emission arising from the SiV⁻ defect is studied under high pressures (up to 17 GPa) and low temperatures (down to 11 K). More specifically, the emission corresponding to SiV⁻ zero phonon line and local vibrational mode and their respective change as a function of pressure and temperature are recorded. This work indicates a promising potential for the SiV⁻ defect as a useful quantum sensor, especially in the context of extreme conditions research.
759

Life & Lifestyle Makeovers: The Promotion of Materialism in <i>Extreme Makeover: Home Edition</i>

Ratliff, Kari 24 July 2007 (has links)
No description available.
760

Experimental and Numerical Study on the Extreme Behaviors of Sliding Isolation Bearings

Bao, Yu January 2017 (has links)
Sliding isolation bearings are used widely around the world to minimize damage to structures and their contents during earthquakes. Past studies have typically focused on the behavior of sliding isolation bearing under design conditions; however, as the performance-based earthquake engineering advances, it is necessary and critical to understand the ultimate or even failure behavior, of structural systems under extreme conditions. Using a double friction pendulum bearing with non-articulated slider as an example, this thesis comprehensively investigates the extreme behavior of the sliding bearing components as well as steel frame buildings isolated using these bearings. This thesis is comprised of two major parts. The first includes numerical and experimental studies of double friction pendulum bearings at the component-level. Finite element investigation shows that depending on the superstructure mass there are two major failure modes for the double friction pendulum bearings. When the superstructure mass is sufficiently large, the failure mode is dominated by the restraining rim yielding; however, when the mass is relatively small, its failure mode shifts to bearing uplift. A simplified analytical model which can directly simulate the impact and uplift behavior of double friction pendulum bearing is also implemented, comparing well to the finite element analysis. Then, to validate the ability of the models to predict extreme behavior as well as to investigate the effect of the restraining rim design, which varies around the world, an experimental study was carried out. Uplift behavior and significant rim yielding were observed during the shake table tests. Moreover, other response parameters, including uplift and shear forces, are evaluated and compared among different rim designs. It is found the restraining rim design has a substantial influence on the bearing’s extreme behavior. The second part of the thesis investigates the system-level behavior of steel frame buildings isolated with double friction pendulum bearings. It is found that the stiffness of the superstructure largely dictates the system-level failure modes and collapse probability. Initially, bearings with rigid restraining rims are investigated. For flexible moment-resisting frames, the system-level failure modes are mixed: both the bearing uplift and superstructure yielding contribute; also, using current code-minimum design results in acceptably low probability of collapse. However, for stiff concentrically-braced frames, the impact force can impose large ductility demands on the superstructure regardless of its strength. As a result, the system-level failure comes exclusively from superstructure yielding, and only by increasing bearing’s displacement capacity beyond the minimum code allowed can the design meet as acceptably low collapse probability. When flat rims are used instead for the bearing design, the failure modes for both building types are exclusively bearing failure. Furthermore, while it is more apparent for concentrically-braced frames, using flat rims for the bearings can reduce the collapse probability compared to using rigid rims. / Thesis / Doctor of Philosophy (PhD)

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