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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.
61

Simulation of helium flow through ion guide with COMSOL multiphysics

Hedkvist, Adam, Ahrman, Henrik January 2016 (has links)
The program COMSOL Multiphysics was used to simulate a flow of helium gas transporting ionized fission products out of an ion guide. Two important parameters to study from the simulation was the evacuation time and velocity of the ions. The mean evacuation time was shown to be 0.1173s, and the velocity of a single particle peaked at 2500m/s, 1000-1500m/s being more common.
62

In the Culture of Truthiness: Comic Criticism and the Performative Politics of Stephen Colbert

Holcomb, Justine Schuchard 05 June 2009 (has links)
I analyze comedian Stephen Colbert's performances as the bloviating "fake" pundit, "Stephen Colbert." Colbert's work reflects the progression of personality-driven media and performance-driven society. His frequent shifts and blending of characters – from actor and entertainer to pundit and politician – call attention to the similarly character-driven nature of "real" figures in politics and media. Using Kenneth Burke's theory of tragic and comic frames of acceptance, I analyze three sets of Colbert's performances – hosting The Colbert Report, speaking at the White House Correspondents' Association dinner, and running for president – as well as the conventional situations and discourses he complicates. I argue that Colbert's comic critique provides perspective by incongruity about the processes of production, mediation, and persuasion in the business of news punditry – and the literal staging of politics performed as entertainment.
63

När Boxholms kyrka byggdes : Boxholms aktiebolags beslut om kyrkobyggande och dess förhållande till väckelse och samhällsförändring

Birath, Erik January 2011 (has links)
No description available.
64

Pre-Study for a Battery Storage for a Kinetic Energy Storage System

Svensson, Henrik January 2015 (has links)
This bachelor thesis investigates what kind of battery system that is suitable for an electric driveline equipped with a mechanical fly wheel, focusing on a battery with high specific energy capacity. Basic battery theory such as the principle of an electrochemical cell, limitations and C-rate is explained as well as the different major battery systems that are available. Primary and secondary cells are discussed, including the major secondary chemistries such as lead acid, nickel cadmium (NiCd), nickel metal hydride (NiMH) and lithium ion (Li-ion). The different types of Li-ion chemistries are investigated, explained and compared against each other as well as other battery technologies. The need for more complex protection circuitry for Li-ion batteries is included in the comparison. Request for quotations are made to battery system manufacturers and evaluated. The result of the research is that the Li-ion NMC energy cell is the best alternative, even if the cost per cell is the most expensive compared to other major technologies. Due to the budget, the LiFeMnPO4 chemistry is used in the realisation of the final system, which is scaled down with consideration to the power requirement.
65

Ég meina það sé úr Eddu. Jón Rúgmanns avskrift av Uppsala-Eddans Gylfaginning ur handskriften R 683

Romano, Christian January 2013 (has links)
Uppsatsen presenterar en diplomatarisk utgåva av ett stycke text ur handskriften R 683, från senare hälften av 1600-talet. Texten är en avskrift av delen Gylfaginning ur Snorri Sturlusons Edda enligt versionen nedskriven i handskriften DG 11, från tidigt 1300-tal. Uppsatsens syfte är att presentera en hittils relativt ostuderad text som en självständig skriftprodukt, samt försöka att spåra dess specifika drag som skiljer den från dess ursprungstext samt övriga versioner av Snorris Edda. Undersökningen har genomförts utifrån ett nyfilologiskt perspektiv, inte med tanke på dess relation till övriga versioner utan med fokus på vad som egentligen står i handskriften. Resultatet visar att texten i R 683 skiljer sig något från DG 11, och jämförelseundersökningen med övriga Edda-versioner visar att skrivaren, Jón Rúgmann, använt sig av andra källor för sin avskrift, i synnerhet de i handskrifterna Codex Regius, Codex Wormianus samt Peder Resens (Resenius) utgåva av Laufás Edda. Samtidigt visar skrivarens arbete tecken på en personlig kunskap i den medeltida isländska textproduktionen, vilket förklarar de tillägg och kommentarer som inte är direkt tagna ur texter utan tyder på vidare forskning eller förkunskaper. Slutligen lyfter uppsatsen fram Jón Rúgmanns vetenskapliga förtjänster i den nordiska filologins tidiga etablering i Sverige samt presenterar den stora potential i förbisedda handskrifterna som R 683.
66

The roles of the visual in picturebooks beyond the conventions of current discourse /

Catalano, Dominic, January 2005 (has links)
Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains x, 555 p. Includes bibliographical references (p. 512-555). Available online via OhioLINK's ETD Center.
67

Termisk hantering av litium-jon- batterier i elektriska drivsystem / Thermal management of lithium-ion batteries in electric vehicle drives

BERGVALL, JOHAN, JOHANSSON, SEBASTIAN January 2012 (has links)
The automotive market is currently undergoing a historical change where stricter emission legislations and ever increasing fuel costs have intensified the search for effective alternatives to the conventional internal combustion engine, which has resulted in a substantial trend towards electrification of powertrains. Storage of electrical energy is the fundamental component in this technology where the lithium-ion batteries are currently considered as the most appropriate solution. Lithium-ion batteries, however, as other types of batteries, can only be used efficiently and durably within a specific temperature range.This Master thesis has been carried out in collaboration with Electroengine in Sweden AB, situated in Uppsala, which has an ongoing project regarding development of a modular battery system for electric powertrains. The project is at a stage where an initial prototype has been developed which provides the foundation for this thesis. The study has addressed the battery system performance from a thermal perspective, in order to validate the ability of the system to create a thermally serviceable environment for the lithium-ion battery cells. The work has therefore been focused on verifying whether the existing structure provides sufficient heating and cooling functions. Based on the validation review, the current prototype's performance is presented and suggestions for improvements are submitted.Knowledge in the relevant area has been acquired through an extensive pre study concerning competing temperature management systems, basic thermodynamics, potential pathways for heat transfer and temperature-related characteristics for battery cells. Further, testing was conducted to obtain cell-generated heat power at varying load, state of charge and temperature. Henceforth the test data was used for the creation of simulation models in (COMSOL, 2012) and numerical analysis in (MATLAB, 2011) regarding the battery system's thermal behavior for various operating conditions in order to verify the system's temperature-regulating sustainability and to design the required cooling and heating functions.The conclusion of the study indicates that the existing design possesses acceptable dimensioning of cooling and heating properties. For further development of the battery system's temperature regulatory functions, a number of system improvement measures are necessary. Prioritized improvements are adaptive cooling which is only activated when needed, and cooling through the connecting plates of the battery cells. Implementation of improvement measures will result in an extended lifespan of the battery cells, and higher overall efficiency of the battery system. / Fordonsmarknaden genomgår idag en historisk förändring där striktare utsläppslagstiftningar och ständigt ökande bränslekostander har intensifierat sökandet efter effektiva alternativ till den konventionella förbränningsmotorn, vilket medfört en omfattande trend mot elektrifiering av drivlinor. Lagring av elektrisk energi utgör den fundamentala komponenten inom denna teknologi där litium-jon-batterier idag anses som den mest adekvata lösningen. Litium-jon-batterier är dock, såsom andra typer av batterier, temperatursensibla och kan endast brukas effektivt och durabelt inom ett specifikt temperaturområde.Detta examensarbete har genomförts i samarbete med Electroengine in Sweden AB i Uppsala som har ett pågående projekt där ett modulärt batterisystem för elektriska drivlinor utvecklas. Projektet befinner sig i ett stadie där en initial prototyp framtagits vilken utgör fundamentet för ifrågavarande examensarbete. Genomförd studie har behandlat batterisystemets prestanda ur ett termiskt perspektiv med syfte att validera systemets förmåga att skapa en termiskt tjänlig miljö för ingående litium-jon-battericeller. Arbetet har följaktligen fokuserats på att verifiera huruvida den befintliga konstruktionen tillgodoser satisfierande värmnings- och kylningsfunktioner. Utifrån valideringsgranskningen har den befintliga prototypens prestanda presenterats och förbättringsförslag framlagts.Via en omfattande förstudie berörande konkurrerande temperaturhanteringsystem, grundläggande termodynamik, potentiella vägar för värmetransport och battericellernas temperaturrelaterade egenskaper inhämtades en solid kunskapsbas inom berört område. Vidare genomfördes tester för erhållande av cellgenererad värmeeffekt vid varierande last, laddningsstatus och temperatur. Fortsättningsvis brukades testdata för upprättande av simuleringsmodeller i (COMSOL, 2012) och numerisk analys i (MATLAB, 2011) gällande batterisystemets termiska beteende för olika driftförhållanden för att därigenom verifiera systemets temperaturreglerande bärkraftighet och dimensionera erforderlig kylning och värmning.Slutsaten av genomförd studie är att den befintliga konstruktionen innehar godtagbar dimensionering av kyl- respektive värmningsfunktion för tilltänkt applikation. För vidareutveckling av batterisystemets temperaturreglerande funktion återfinns ett flertal systemförbättrande åtgärder där prioriterade förbättringar utgörs av adaptiv kylning som endast aktiveras vid behov och kylning via battericellernas kontaktbleck. Implementering av förbättringsförslag resulterar i förlängd livslängd för battericellerna samt högre total verkningsgrad för batterisystemet.
68

Thermal behaviour of Li-ion cell : Master Thesis project at Volvo GTT ATR / Termiskt beteende av Li-jon celler

MALTSEV, TIMOFEY January 2012 (has links)
Examensarbetet gjordes på Volvo Group Trucks Technology. Målet med arbetet var att studeravärmeutveckling i Li-jon cell för hybrid- och elbilar, HEV och EV. Battericeller undersöktesunder sina normala arbetsförhållanden och vid förstörande prov. Undersökningen baserades påcellernas yttemperatur. Arbetet beskrev cellernas beteende och syftade att vara ett underlag förkonstruktörer av batterisystem.En litteraturstudie gjordes för att studera faktorer som påverkar värmeutvecklingen. Sedananalyserades källor till samtliga faktorer. En moduleringsmetod för analys av cellensvärmeeffektivitet togs fram. Miljöpåverkan och ekonomiska aspekter av batterier undersöktes.Tre tester togs fram för att undersöka värmeutvecklingsfaktorer på fem celler. De flestafaktorerna var externa såsom laddning och urladdning, puls och kontinuerlig ström ochomgivningstemperatur. En infraröd kamera användes vid experimenten.Testerna visade hur olika faktorer påverkade cellernas temperatur. Vidare analys av källor visadekritiska områden i cellernas konstruktion.Förstörande värmeprov gjordes på tre par av celler. Dessa värmdes upp till 300°C vilketorsakade ”thermal runaway”. I vissa fall gick temperaturen över 600°C och celler fattade eld.Olika kemiska sammansättningar och uppbyggnad av cellerna gjorde att de betedde sig olika vidgenomförda tester.Testerna visade att olika celler presterade olika vid liknande testförhållanden. Därför är detviktigt att ta fram specifikationer för användningsförhållanden för att välja ut en cell för ettbatterisystem. Sedan kan prestandan av olika celler jämföras och effektivitet kan utvärderas församma belastningscyklar.Thermal Management System kan förhöja batteriets effektivitet och måste designas medanvändningsförhållanden i åtanke. Batteriernas säkerhet är väldigt viktig och människor får inteskadas av batterier. Därför måste säkerheten finnas i åtanke i alla steg av batteridesign.Arbetets resultat blev en sammanfattning av viktiga faktorer och specifikationer för batteridesignsom baserades på värmeutvecklingen. Samtliga riktlinjer sammanfattades i Appendix 5. / Master thesis work was done at Volvo Group Trucks Technology. Aim of the project was tostudy thermal behaviour of Li-ion battery for hybrid and electric vehicles, HEVs and EVs.Battery cells were tested in regular working conditions and abuse conditions. Surfacetemperature of cells was chosen for studying heat evolution.A literature study was conducted to research factors that influence cell temperature. Analysis ofsources of these factors was then performed. A modelling method for analyzing cell thermalefficiency was designed. Sustainability and economics aspects of batteries were also studied.When factors were established three tests were designed to study their effects. Five cells werestudied. Tests mainly examined external factors such as charge and discharge, pulse andcontinuous current, ambient temperature to name a few. An infrared camera was used.Study showed how different factors influenced cell temperature. Further analysis of sourcespointed out some hot spots of cell designs.Thermal abuse test were performed on three pairs of cells. Cells were heated up to 300°C andwent through thermal runaway which in some cases increased temperatures up to 660°C in lessthan a second and caused fire. Different cell chemistries and cell designs reacted differently tothe abuse conditions.A conclusion was reached that cells performed differently in similar test conditions. Whendesigning a battery system a set of specifications for usage conditions is crucial for choosing acell. When conditions and load cycles are known cells can be tested and their thermal andelectrical efficiency evaluated.Thermal Management System TMS can largely enhance cell efficiency and lifecycle. Suchsystem must also be designed according to usage conditions and particular cell’s performance.Battery safety showed to be a very important factor of designing a battery system. Humans shallnot be injured by systems with batteries which must be kept in mind during design.Work resulted in summary of important factors and specifications for designing a battery systembased on cell thermal behaviour. These guidelines are presented in Appendix 5.
69

Block Copolymer Lithographyfor Nano-porous Oxide Thin Films

Liu, Yandi January 2018 (has links)
This thesis focuses on employing a new patterning technique called block copolymer lithography to transfer the nano-porous pattern from the polymer template to the underlying oxide thin film. Nano-porous block copolymer films are produced by spin-coating polymer solution on wafers followed by annealing, UV exposure and development processes. Reactive-ion etching is then used to etch the oxide films based on the pattern of polymer template and the polymer is then removed. The obtained oxide microstructure is characterized by SEM, showing a nanomesh of microdomains with the same hole size and density as the initial block copolymer layer. The advantages of block copolymer lithography include uniform nanopatterning, cost efficiency and simple processing. The nano-porous oxide thin films could be used as hard mask for nanopatterning in microelectronics and for energy storage applications. / Denna avhandling fokuserar på användningen av en ny mönstringsteknik som kallas block-sampolymerlitografi som används för att överföra nano-porösa mönster från polymermaller till en underliggande oxidtunnfilm. Nano-porösa blocksampolymerfilmer framställs genom spinbeläggningspolymerlösning på skivor följt av glödgning, UV-exponering och utvecklingsprocesser. Reaktionjon etsning används sedan för att etsa oxidfilmerna baserat på mönstret av polymermaller och därefter blir polymeren avlägsnad. Den erhållna oxidmikrostrukturen karakteriseras av SEM, som visar en nanomesh av mikrodomäner med samma hålstorlek och densitet som det ursprungliga blocksampolymerskiktet. Fördelarna med block-sampolymerlitografi innefattar likformig nanomönstring, kostnadseffektivitet och enkel bearbetning. De nanoporösa oxidtunnfilmerna kan användas som en hard mask för nanomönstring i mikroelektronik och för energilagringsapplikationer.
70

An Actor's Approach: Stepping Into A Role And A World Of The Past

Gosselin, Danielle 01 January 2013 (has links)
To step into a character and a world of the past, the actor must not discard the present, but seek to find connections and links between the worlds. I was cast in the Orlando Shakespeare Theater production of Sense and Sensibility, a Jon Jory adaptation of Jane Austen’s novel, in the role of Lucy Steele. This was an equity production, and it ran February 6th – March 17th, 2013, in the Orlando Shakespeare Theater’s Margeson Theater. Lucy is a female character from England in a period often referred to as the Regency era. As a woman from today’s United States of America, first I explored how Lucy’s words and actions fit into the society of her time, and second I explored how I, a contemporary actor, could organically step into her shoes. One of the greatest tools I had to help me address these questions was the playwright himself, Jon Jory. He was at the Orlando Shakespeare Theater for the 2012 Harriett Lake Festival of New Plays, during which he gave a keynote address and taught a master class in acting, in which I participated. Furthermore, I had the unique opportunity to personally interview him regarding Sense and Sensibility and his connection to the world of Austen and her characters. Along with applying this insight, I applied tools from his acting master class to my work on his Sense and Sensibility text. This special access to the playwright greatly influenced the work and served as a key into Lucy’s world. In addition to working with the playwright, I further researched Austen and her work, because Lucy and her world originate there. I explored various resources about England’s Regency era society and the role of women in this society. By comparing the world and people of the play to the current cultural and political landscape with which I am most familiar, I found iii fundamental links between people living in different times and places, breaking down walls between Lucy’s world and my own. Finally, this performance thesis project utilized the practical acting, voice, and movement skills, which I cultivated in my studio work as an MFA acting candidate at the University of Central Florida. It was a wonderful opportunity as an aspiring young actor to participate in an equity production and work with professional actors. I exercised my stage dialects training by using a standard British dialect, and I applied what I learned in my theatre styles acting class and in various movement classes to develop the behavior and physicality of my character. In order to preserve the new information gained from this study, I chronicled my explorations and discoveries throughout the rehearsal and production process. Through my work with the playwright Jon Jory, my research on Jane Austen and the Regency era, and my application of what I learned in the studio, I strove to create a model process for an actor to utilize when stepping into a role and a world of the past.

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