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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.
121

Alemanha secreta : biografia e história no círculo de Stefan George / Secret Germany : biography and history in the George Circle

Silva, Walkiria Oliveira January 2013 (has links)
Dissertação (mestrado)—Universidade de Brasília, Programa de Pós-Graduação em História, 2013. / Submitted by Alaíde Gonçalves dos Santos (alaide@unb.br) on 2014-06-04T13:41:46Z No. of bitstreams: 1 2013_WalkiriaOliveiraSilva.pdf: 937333 bytes, checksum: 43c619bd4e77ba2c02d85a03a5573b30 (MD5) / Approved for entry into archive by Guimaraes Jacqueline(jacqueline.guimaraes@bce.unb.br) on 2014-06-04T14:38:54Z (GMT) No. of bitstreams: 1 2013_WalkiriaOliveiraSilva.pdf: 937333 bytes, checksum: 43c619bd4e77ba2c02d85a03a5573b30 (MD5) / Made available in DSpace on 2014-06-04T14:38:54Z (GMT). No. of bitstreams: 1 2013_WalkiriaOliveiraSilva.pdf: 937333 bytes, checksum: 43c619bd4e77ba2c02d85a03a5573b30 (MD5) / Esta dissertação objetiva analisar como a obra de Ernst Kantorowicz, Kaiser Friedrich der Zweite, relaciona-se com a fundamentação da identidade nacional alemã durante os anos da República de Weimar. Ernst Kantorowicz foi membro do Círculo de Stefan George, um dos principais movimentos culturais da Alemanha durante as três primeiras décadas do século XX. Por isso, é indispensável apresentar as contribuições do Círculo de Stefan George para as discussões acerca da História e de sua escrita. A análise da obra de Kantorowicz encontra-se indissociada das propostas vinculadas pelo Círculo de Stefan George. Este trabalho está divido em três capítulos: o primeiro abarca o poeta, Stefan George, e a formação de seu Círculo. O segundo apresenta as ideias do Círculo sobre o conhecimento histórico e os principais conceitos formulados por alguns membros do Círculo de George. O último analisa a obra de Kantorowicz a fim de observar como a biografia do Imperador Frederico II contribuiu para a fundamentação e reinterpretação da identidade nacional alemã e como se relaciona com a escrita da história do Círculo de Stefan George. _______________________________________________________________________________________ ABSTRACT / The present dissertation aims to analyse Ernst Kantorowicz’s work, Kaiser Friedrich der Zweite, published in 1927, and its relation to the German national identity’s substantiation during the Weimar Republic. Ernst Kantorowicz was a member of the George Circle, one of the most important cultural movements in Germany during the first three decades of twentieth century. Taking in account his contributions to the George Circle on the debate on History and historiography, the analysis of Kantorowicz’s work should be inseparable of the ideas of the George Circle. This work is divided in three chapters: the first one presents the poet, Stefan George, and the formation’s process of his Circle. The second shows the ideas of the Circle about the historical knowledge and the main concepts formulated by some members of the George Circle. The last one analyses Kantorowicz’s work in order to observe how the biography of the Emperor Frederick II contributed to found the ground and reinterpretat the German national identity in its relation to the historiography of the George Circle.
122

Vem snackar i spelrummet? : En kvantitativ undersökning av Stefan Löfven och Donald Trumps mediala utrymme i Aftonbladet. / Look who is talking in the media : A quantitavie investigation of Donald trump and Stefan Löfvens medial space in Aftonbladet

Kungberg, Mimmi, Rydeberg, Amelia January 2017 (has links)
This study aims to show how much space Donald Trump and Stefan Löfven get in the digital edition of the Swedish tabloid Aftonbladet. To investigate this, a quantitative content study was used, counting the number of articles in which they appear between January 21st 2017 and July 21st 2017. In total 967 news articles were included in the study where articles appearing in the entertainment and sports section were excluded as well as editorials and columns.   In the articles we counted the amount of words and how long the quotes of the two persons were. We also counted how many articles in which both Donald Trump and Stefan Löfven appear and how the quotes were distributed between them. To count the articles we created a coding scheme with rules for interpretation.   The result of the study was that Donald Trump appeared more frequently in the tabloid than Stefan Löfven. This tells us that Aftonbladet priorities news about Donald Trump over news about Stefan Löfven which can be explained by globalisation, which is one of the theories used in this study, along with the theory of news values. However it was also clear that procentually Stefan Löfven was quoted more than Donald Trump. This can mean that even though globalisation brings nations across the world closer to each other, the physical distance still has a factor in what news sources appear in the news media.
123

Pervaporation of alcohol/water mixtures using ultra-thin zeolite membranes:membrane performance and modeling

Leppäjärvi, T. (Tiina) 16 June 2015 (has links)
Abstract The production of liquid transportation fuels such as bioethanol and more recently also biobutanol from renewable resources has received considerable attention. In the production of bio-based alcohols, the separation steps are expensive as the mixtures to be separated are dilute. As an energy-efficient separation technology, pervaporation is considered to be a potential process in biofuel purification. One of the main constraints in the commercialization of pervaporation has been low membrane fluxes, and the consequent high costs due to the high membrane area needed. In order to obtain high fluxes, the membranes should be as thin as possible. In this thesis, the performance of ultra-thin zeolite membranes in pervaporation was investigated. Binary ethanol/water and n-butanol/water mixtures were studied using both hydrophobic and hydrophilic zeolite membranes for alcohol concentration, as well as dehydration. The development of pervaporation membranes and processes has been mainly empirical. Process modeling, however, is an indispensable tool in process design. In this work, the pervaporation performance of the studied membranes was evaluated on the basis of experimental results in combination with mathematical modeling. Due to the low film thickness of the studied membranes, the fluxes were generally higher than reported earlier. Nevertheless, the evaluation in this work showed that the pervaporation performance of the ultra-thin membranes decreased due to flux limitation by membrane support. In this work, pervaporation was modeled by applying both a semi-empirical and a detailed Maxwell-Stefan based mass transfer model. The latter model considers explicitly both adsorption and diffusion, i.e. the phenomena involved in separation by pervaporation. The description of the support behavior was included in the models. Maxwell-Stefan formalism was applied in unary pervaporation for the determination of diffusivities in zeolite membranes. The models performed well within the range of experimental data. Additionally, a practical modeling approach was developed in this work to predict the temperature dependency of adsorption on zeolites. The developed approach can be utilized, e.g., in pervaporation modeling. Thus, this thesis provides knowledge of using ultra-thin zeolite membranes in the pervaporation of alcohol/water mixtures, and offers tools for pervaporation modeling. / Tiivistelmä Kiinnostus uusiutuvista raaka-aineista valmistettavia liikennepolttoaineita, kuten bioetanolia ja -butanolia, kohtaan lisääntyy koko ajan. Biopohjaisten alkoholien tuotannossa etenkin erotusvaiheet ovat kalliita, koska erotettavat liuokset ovat laimeita. Pervaporaatio on energiatehokas kalvoerotusmenetelmä ja sen vuoksi potentiaalinen osaprosessi biopolttoaineiden tuotantoon. Pervaporaation kaupallistamisen merkittävimpiä rajoitteita ovat olleet alhaiset ainevuot, jotka johtavat suureen kalvopinta-alan tarpeeseen ja näin ollen korkeisiin kustannuksiin. Korkean ainevuon saavuttamiseksi kalvojen tulisi olla mahdollisimman ohuita. Tässä väitöstyössä tutkittiin hyvin ohuiden zeoliittimembraanien suorituskykyä pervaporaatiossa. Kohteena olivat binääriset etanoli/vesi- ja n-butanoli/vesiseokset, joista väkevöitiin alkoholeja tai poistettiin vettä hydrofobisia ja hydrofiilisiä zeoliittimembraaneja käyttäen. Pervaporaatiossa käytettävien kalvojen ja pervaporaatiota hyödyntävien prosessien kehitystyö on ollut pääasiassa kokeellista. Prosessimallinnus on kuitenkin tärkeä työkalu prosessisuunnittelussa. Tässä työssä membraanien suorituskykyä pervaporaatiossa arvioitiin sekä kokeellisesti että mallinnuksen keinoin. Käytettyjen kalvojen ohuuden ansiosta tässä työssä saavutetut ainevuot olivat yleisesti ottaen korkeampia kuin aiemmin raportoiduilla membraaneilla. Ohuilla kalvoilla tukimateriaalin aiheuttama aineensiirron vastus oli kuitenkin merkittävä, alentaen membraanien suorituskykyä. Tässä työssä pervaporaatiota mallinnettiin käyttäen sekä puoliempiiristä että yksityiskohtaisempaa Maxwell-Stefan -pohjaista mallia. Jälkimmäisessä mallissa adsorptio ja diffuusio, eli ilmiöt joihin erotus pervaporaatiossa perustuu, otetaan eksplisiittisesti huomioon. Myös tukimateriaalin vaikutukset huomioitiin käytetyissä malleissa. Maxwell-Stefan -mallinnusta käytettiin puhtaiden komponenttien pervaporaatiossa zeoliittimembraanin diffuusiokertoimien määrittämiseksi. Käytettyjen mallien suorituskyky kokeellisella alueella oli hyvä. Tässä työssä kehitettiin lisäksi helppokäyttöinen menetelmä aineiden adsorptiokäyttäytymisen ennustamiseen zeoliiteissa eri lämpötiloissa. Kehitettyä menetelmää voidaan hyödyntää esimerkiksi pervaporaation mallinnuksessa. Kokonaisuudessaan väitöstyöstä saadaan tietoa ultraohuiden membraanien käytöstä pervaporaatiossa sekä työkaluja pervaporaation mallinnukseen.
124

När det frihetliga möter det auktoritära : Foreningen av fascism och anarki

Nilsson, Jonas January 2017 (has links)
Uppsatsens undersökande studie ämnar till att skapa en förståelse till varför två till synes diametralt motsatta politiska perspektiv kan sammanstråla, via två framträdande opinionsbildare, i sitt uttalade stöd till en och samma presidentkandidat. Analysen utgår ifrån tre olika policyområden för Trumps, 2016, presidentkandidatur, och hur Richard Spencer samt Stefan Molyneux förhåller sig till dessa. Spencer är en av den amerikanska alternativa högerns förgrundsfigurer och Molyneux en politisk opinionsbildare för voluntarism och anarko-kapitalism. De båda stödjer Trumps policyinriktningar fullt ut, stödet motiveras dock olika utifrån respektives teoretiska utgångspunkt, men det finns ändå tydliga föreningspunkter som binder dem samman som ger upphov till vad som skulle kunna hänvisas som anarko-fascism.
125

Silicalite-1 Membranes Synthesis, Characterization, CO2/N2 Separation and Modeling

Tawalbeh, Muhammad January 2014 (has links)
Zeolite membranes are considered to be a promising alternative to polymeric membranes and they have the potential to separate gases under harsh conditions. Silicalite-1 membranes in particular are easy to prepare and suitable for several industrial applications. In this research project, silicalite-1/ceramic composite membranes were prepared using the pore plugging hydrothermal synthesis method and supports with zirconium oxide and/or titanium oxide as active layers. The effect of the support’s pore size on the morphology and permeation performance of the prepared membranes was investigated using five supports with different active layer pore sizes in the range of 0.14 – 1.4 m. The prepared membranes were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), electron diffraction spectrometer (EDS), single gas and binary gas mixtures permeation tests. The results confirmed the presence of a typical silicalite-1 zeolite structure with a high internal crystalline order grown inside the pores of the active layer of the supports, with a dense film covering most of the supports active layers. Silicalite-1 crystals in the prepared membranes were preferably oriented with either a- or b-axes perpendicular to the support surface. Single gas permeation results illustrated that the observed permeances were not directly related to the kinetic diameter of permeants. Instead, the transport of the studied gases through the prepared membranes occurred by adsorption followed by surface diffusion mechanism. Binary gas tests performed with CO2 and N2 mixtures showed that the prepared membranes were selective and very permeable with CO2/N2 permselectivities up to 30 and a CO2 permeances in the order of 10-6 mol m-2 Pa-1 s-1. A model was developed, based on Maxwell−Stefan equations and Extended Langmuir adsorption isotherm, to describe the transport of binary CO2 and N2 mixtures through the prepared silicalite-1 membranes. The model results showed that the exchange diffusivities (D12 and D21) were less dependent on the feed pressure and feed composition compared to the permeances and the permselectivities. Hence, they are more appropriate to characterize the intrinsic transport properties of the prepared silicalite-1 membranes.
126

’Ich fühle luft von anderem planeten’ - ein George-Vers kommentiert den Beginn der Neuen Musik. Analyse eines Themas von Arnold Schönberg

Pfisterer, Manfred 24 January 2020 (has links)
No description available.
127

Politisk strategi : En direkt nödvändighet eller politisk smartness? / Political strategy : A direct necessity or political smartness?

Lindblad, Petter January 2022 (has links)
The purpose of this essay is to examine and compare two different minority governments that have been ruling in Sweden since the one chamber parliament was introduced in 1971. This examination will be helpful to make conclusions about the political strategies that have been used during their time in the government. This essay will also try to answer why these strategies were used, if the motives were just tactical or if they were based on ideological theories. In this essay I will review and compare the government of Ola Ullsten from 1979 and the government of Stefan Löfven from 2014 to see if there are any similarities between their strategies and also what effects their time as prime ministers of Sweden have on the aspects of democracy and efficiency. Sweden is known for its negative parliamentarism which often generates weak minority governments and the cases of this study are examples of that. The question to be answered is wheater or not political strategy is absolutely necessary and a result of a selection system that forces politicians to use strategy to be able to rule or if political strategy is used as a weapon to maximize their self interests.
128

Blodtörstiga demoner eller attraktiva varelser : En studie om gestaltningen av vampyrerna i Twilight och The Vampire Diaries

Karlsson, Linn January 2021 (has links)
Syftet med den här uppsatsen bygger på en gestaltningsanalys av vampyrerna Edward Culleni Twilight och Stefan Salvatore i The Vampire Diaries där fokuset handlar om hur dessavampyrkaraktärer gestaltas genom olika aspekter som utseende, kroppsspråk, humör,beteende och agerande. Jens Eders karaktärsklocka är den metod jag använt mig av för attgöra analysen på vampyrkaraktärerna. Vampyrernas samspel med andra karaktärer är ocksåen viktig del i analysen. Både samspelet med andra vampyrer och samspelet med människor.Resultatet visar att den moderna vampyren har en större utsträckning mot den “klassiska”vampyren som nästintill bara har monstruösa drag utan någon empati eller ångest över sinahandlingar. Både Stefan och Edward har både monstruösa och mänskliga skildringar i derasgestaltning som både följt med genom historien eller uppkommit under modern tid.Vampyrer har traditionellt setts som hjärtlösa monster som bara dödar. Så ser det inte ut idagen moderna vampyrfilmer och serier.
129

Ledarskapets roll inom utrikespolitiken: : En jämförande fallstudie av Göran Perssons- och Stefan Löfvéns relationer till staten Israel

Otterberg, Axel January 2021 (has links)
The purpose of this study is to find explanations for why Göran Persson and Stefan Löfvén and their respective governments chose different political expressions towards the state of Israel. The two theories I have chosen are about whether the political leadership of these two different prime ministers has been significant for the political relationship with the state of Israel, and whether there has been an existing personal interest in the foreign policy context precisely with regard to Israel. I want to know if the different attitudes of these two prime ministers to Israel may be due to the two different types of leadership styles that Persson and Löfvén had. Göran Persson has also seemed to expressed a deeper interest in the Jewish state, which results me wanting to investigate whether this may be a factor in Göran Persson being more anxious to change the Social Democrats' foreign policy towards Israel, compared toStefan Löfvén. What I find remarkable is that these two prime ministers who belong to the same ideological party with the Social Democratic political principles as their basis still ended up on two such different levels when it comes to relations with Israel. I will do study with a qualitative method, and with a research design called a comparative case study. To my help I will use the “Most Similar Design System” which is a research design that compares two similar cases, in this context two Social Democratic prime ministers, but which stands out remarkably on one point; the foreign policy and the relationship with the state of Israel.
130

Modeling Phase Change Heat Transfer of Liquid/vapor Systems in Free/porous Media

Wilson, James 01 January 2015 (has links)
Effective solvent extraction incorporating electromagnetic heating is a relatively new concept that relies on Radio Frequency heating and solvents to replace steam in current thermal processes for the purpose of extracting bitumen from oil rich sands. The work presented here will further the understanding of the near wellbore flow of this two phase system in order to better predict solvent vaporization dynamics and heat rates delivered to the pay zone. This numerical study details the aspects of phase change of immiscible, two component, liquid/vapor systems confined in porous media heated by electromagnetic radiation, approximated by a spatially dependent volumetric heat source term in the energy equation. The objective of this work is to utilize the numerical methodology presented herein to predict maximum solvent delivery rates to a heated isotropic porous matrix to avoid the over-saturation of the heated pay zone. The total liquid mass content and mean temperature in the domain are monitored to assess whether the liquid phase is fully vaporized prior to flowing across the numerical domain boundary. The distribution of the volumetric heat generation rate used to emulate the physics of electromagnetic heating in the domain decays away from the well bore. Some of the heat generated acts to superheat the already vaporized solvent away from the interface, requiring heat delivery rates that are many times greater than the energy required to turn the liquid solvent to vapor determined by an energy balance. Results of the parametric study from the pay zone simulations demonstrate the importance of the Darcian flow resistance forces added by the porous media to stabilize the flow being pulled away from the wellbore in the presence of gravity. For all cases involving an increase in solvent delivery rate with a constant heat rate, the permeability range required for full vaporization must decrease in order to balance the gravitational forces pulling the solvent from the heated region. For all conditions of permeability and solvent delivery rates, sufficiently increasing the heat rate results in complete vaporization of the liquid solvent. For the case of decreasing solvent delivery rate, a wider range of higher permeabilities for a given heat rate can be utilized while achieving full vaporization. A three dimensional surface outlining the transition from partially vaporized to fully vaporized regimes is constructed relating the solvent delivery rate, the permeability of the porous near wellbore zone and the heat rate supplied to the domain. For the range of permeabilities ~3000mD observed in these types of well bores, low solvent delivery rates and high heat rates must be utilized in order to achieve full vaporization.

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