• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 115
  • 109
  • 26
  • 23
  • 23
  • 16
  • 6
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 2
  • Tagged with
  • 362
  • 75
  • 75
  • 74
  • 61
  • 61
  • 52
  • 49
  • 43
  • 42
  • 39
  • 38
  • 37
  • 29
  • 29
  • 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.
241

Asset Management of Electrical Transportation Systems with Life Cycle Cost Analysis for Ground Support Equipment: Case Study Stockholm Arlanda Airport

Wirén, Hampus January 2018 (has links)
We have come a long way in the pursuit of reducing our carbon footprint from our way of living, bycontinuously development of batteries and charging infrastructure for electric vehicles to decrease thedemand for fossil fuels, improving the overall energy efficiency and to increase awareness of the problemto the population. One of the industries, that during the last decades has undergone vast improvements,is the development of the airplane engines due to increased emission regulations, for the aviationindustry, and to reduce the costs of air travel. Despite tighter regulations, global impact from travellingby air is increasing due to the explosive increase in number of travels and travellers. In order to copewith the situation, it is of course necessary to further develop fuel and emission effective airplanes, butalso to study the whole chain of emission sources correlated to the air transport industry. So, whilewaiting for improved airplanes there are well known emission effective technologies that can beimplemented already today – implement electric vehicles as support vehicles at airports.Today, and throughout history, most of the focus of air travel has been on the airplane itself. This thesis,that was carried out at KTH Royal Institute of Technology during late spring and autumn 2018, didinstead study the support vehicles used in airports. In this thesis, a generic economic model wasdeveloped in order to estimate the costs involved when replacing traditionally vehicles to suggestedelectrically propelled alternatives. To test and support the development of an economic model, a casestudy has been carried out at Stockholm Arlanda Airport. This case study included a field study to thementioned airport, and in combination with interviews with former employees from one of the groundhandling companies that are currently active in the airport. Raw data was collected over the equipmentand vehicles currently in use. This data was used to describe the vehicles purpose, requirements and toensure that the alternative electric vehicles proposed would offer at least the same performance as thetraditional vehicles. The developed generic economic model was modulated with five stages thatrepresented a selection of input parameters. The collected data became a result in itself and was used asinput to three concurrent theses.The results from the five stages presents the costs during an investment period of between of one tofifteen years. One of the most significant result could be seen from Stage V. This stage showed that thecombined cost to replace all vehicles currently used, with either all new diesel vehicles or electricalternative vehicles, are lower for electric vehicles than for diesel vehicles. Another significant resultcould be seen from the investigation of Stage IV, Stage IV-B, were the model was modulated to representthe case of replacing a vehicle. The results showed that the Letter and Cargo procedures, that travel thefarthest and has the highest fuel consumption of the investigated vehicles, had negative costs throughthe whole investment period. This means that the expenses will always be lower when these vehicles arereplaced. The model was validated through a sensitivity analysis, performed on the discount rates,depreciation rates and as well as costs for battery replacement during the depreciation period. / Vi har kommit långt i vår strävan att minska vårt koldioxidavtryck genom vårat sätt att leva, genom attkontinuerligt utveckla batterier och laddningsinfrastruktur för elfordon med syftet att minskaefterfrågan på fossila bränslen, förbättra den totala energieffektiviteten och öka befolkningensmedvetenhet om problemet. En av de branscher, som under de senaste decennierna har genomgått storaförbättringar, är utvecklingen av flygplansmotorer och regler för flygplan. Men eftersom antaletflygresenärer fortsätter att öka årligen krävs ytterligare arbete för att förbättra den totala effektivitetenoch minska det negativa globala avtrycket från flygresor. Medan väntan på att morgondagens flygplanska utvecklas så finns det teknik som redan kan appliceras idag – elfordon.I dag, och genom historien, har det mesta av all fokus för flygresor varit på flygplanen själva. Dettaexamensarbete, som genomfördes på KTH, Kungliga Tekniska Högskolan, under den senare delen avvåren och hösten 2018, utredde istället de fordon som omger ett flygplan, under den tid flygplanet stårstilla på en flygplats. Under denna uppsats utvecklades en generisk ekonomiskmodell, med syftet attestimera kostnaderna att ersätta och använda elfordon istället för de nuvarande fordonen. För attutveckla den ekonomiska modellen genomfördes en fallstudie på Stockholm Arlanda Airport.Fallstudien innehöll en fältundersökning till den nämnda flygplatsen, och i kombination med intervjuermed tidigare anställda från ett av de marktjänstföretag som är verksamma på flygplatsen, insamladesrådata om vilken utrustning och fordon som vid tillfället användes. Denna data användes för att beskrivafordonens syfte, vilka krav som ställs på fordonen. Detta var för att säkerställa att det valda elfordonetkunde utföra uppgiften. Den utvecklade generiska ekonomiska modellen modulerades med fem steg,som representerade vilka indataparametrar som bör väljas. De insamlade uppgifterna blev ett resultat isig och användes som indata till tre samtidiga avhandlingar.Den generiska modellen resultat presenterade kostnaderna från de fem stegen under en varierandeinvesteringsperiod på ett till femton år. Ett av de viktigaste resultaten var från Steg V, som visade attden sammanlagda kostnaden för att ersätta alla de fordon som för närvarande används, med antingenalla nya dieselfordon eller elektriska alternativa fordon, är lägre för elfordon än för dieselfordon. Detandra betydande resultatet kommer från undersökningen av Steg IV, Steg IV-B. I Steg IV-B moduleradesmodellen i syfte att representera scenariot då ett fordon ska ersättas, där Letter och Cargo procedurernavar de som färdades längst och även har den högsta bränsleförbrukningen utav de undersökta fordonen,hade en negativ kostnad under hela investeringslängden. Detta betyder att kostnaderna alltid är lägre,om fordonet ersätts. Modellen har validerats med hjälp utav en känslighetsanalys som utfördes pådiskonteringsräntan, avskrivningssatsen och kostnader för ersättningsbatterier.
242

Subsystem Design in Aircraft Power Distribution Systems using Optimization

Chandrasekaran, Sriram 26 June 2000 (has links)
The research reported in this dissertation focuses on the development of optimization tools for the design of subsystems in a modern aircraft power distribution system. The baseline power distribution system is built around a 270V DC bus. One of the distinguishing features of this power distribution system is the presence of regenerative power from the electrically driven flight control actuators and structurally integrated smart actuators back to the DC bus. The key electrical components of the power distribution system are bidirectional switching power converters, which convert, control and condition electrical power between the sources and the loads. The dissertation is divided into three parts. Part I deals with the formulation of an optimization problem for a sample system consisting of a regulated DC-DC buck converter preceded by an input filter. The individual subsystems are optimized first followed by the integrated optimization of the sample system. It is shown that the integrated optimization provides better results than that obtained by integrating the individually optimized systems. Part II presents a detailed study of piezoelectric actuators. This study includes modeling, optimization of the drive amplifier and the development of a current control law for piezoelectric actuators coupled to a simple mechanical structure. Linear and nonlinear methods to study subsystem interaction and stability are studied in Part III. A multivariable impedance ratio criterion applicable to three phase systems is proposed. Bifurcation methods are used to obtain global stability characteristics of interconnected systems. The application of a nonlinear design methodology, widely used in power systems, to incrementally improve the robustness of a system to Hopf bifurcation instability is discussed. / Ph. D.
243

Fault Response Analysis and High Voltage Validation of 1 MVA Integrated Motor Drive

Schnabel, Alec Bryan January 2022 (has links)
No description available.
244

Designing for Interconnectedness : Strategies for More-Than-Human Experiences

Fischer, Anton, Jameson, Flora January 2023 (has links)
More-than-human design represents a paradigm shift that decentralises the human in relation to the rest of the living world. As part of this movement, scholars call for a new worldview that recognizes the interconnectedness between human and non-human beings. Prior studies have focused on the experience of human-human connections, leaving the more- than-human largely unexplored. Addressing this gap, this study explores design strategies for fostering feelings and reflections of interconnectedness towards the more-than-human world and associated emotions. With a research-through-design methodology, two workshops were conducted, resulting in six key design strategies and an "interconnectedness experience framework". The strategies were evaluated through a prototype in partnership with AquaPrint, a Swedish company that up-cycles fishing nets into designer furniture. Future research should evaluate the strategies individually and in combinations as well as in a field setting. The presented framework and strategies are intended for practitioners as inspiration in design projects to promote noticing the more-than-human world, and encouraging a posthuman perspective.
245

Reuse and Rethink the Smart City : Co-designing Other Ways of Seeing for a More-Than-Human World

Klefbom, Sanna January 2022 (has links)
The promise of smart cities to deliver new urban efficiencies and optimizations for sustainability is increasingly being questioned for its anthropocentric, universal, and top-down perspectives. Framingcities as computers has been critiqued for its limiting understanding of cities, as well as its lack of dealing with the complexities of real messy cities, with diverse knowledge and lived experiences. However, smart technologies have also been highlighted as having the potential to help us better understand more-than-human perspectives and to reconnect us to the world around us. Situated in thefield of design for social innovation, this thesis contributes to the emerging body of work that is exploring how digital urban environments can include local knowledge and more-than-human perspectives. In a co-design process with the urban agriculture community of Sjöbergen in the city of Gothenburg in Sweden, this thesis explores how local knowledge and values about- and in urban nature can help us think differently about the future of sustainable smart city concepts. With a design process guided by research through design and co-design, this thesis is imagining other smart city narratives that go away from the current top-down and universal perspectives and instead are inspired by values of Sjöbergen of reuse, maintenance, collectivity, and knowledge sharing. The design contribution of this work is a design proposal of a smart city service that reuses old smartphones of citizens into smart city technologies for individual and situated purposes. The design proposal aims to show an alternative view of smart cities grounded in local values and more-than-human perspectives.
246

(En)countering Death: Defenses against Mortality in Five Late Medieval/Early Modern Texts

Horn, Matthew Clive 19 April 2010 (has links)
No description available.
247

Force Fight Study in a Dual Electromechanical Actuator Configuration

Wroble, Daniel G. January 2017 (has links)
No description available.
248

PROGRAMA MAIS EDUCAÃÃO: AVALIAÃÃO DO PROCESSO DE IMPLEMENTAÃÃO NA ESCOLA MUNICIPAL CASIMIRO MONTENEGRO. / MORE EDUCATION PROGRAM: EVALUATION PROCESS IMPLEMENTATION IN MONTENEGRO CASIMIR HALL SCHOOL.

Elizangela Vale Cunha 15 October 2013 (has links)
nÃo hà / A presente pesquisa tem no objeto de estudo o Programa Mais EducaÃÃo, polÃtica pÃblica de educaÃÃo integral, atravÃs da ampliaÃÃo dos tempos e espaÃos de aprendizagem, instituÃda pelo MinistÃrio da EducaÃÃo (MEC). O estudo tem como objetivo principal avaliar o processo de implementaÃÃo do programa, atravÃs do estudo de investigaÃÃo em uma escola pÃblica do municÃpio de Fortaleza â CE. Para tanto escolhemos como lÃcus a Escola Municipal Casimiro Montenegro. Estudamos diferentes concepÃÃes e prÃticas de educaÃÃo integral, encontrado em autores como: AnÃsio Teixeira (1962), Paulo Freire (1968), Guarà (2006), Cavaliere (2000), dentre outros que fundamentaram a investigaÃÃo. Refletimos sobre as concepÃÃes de educaÃÃo integral presentes nos sujeitos envolvidos e analisamos o cotidiano escolar e as repercussÃes decorrentes do Programa Mais EducaÃÃo na comunidade local, e relacionamos, ainda, com a intersetorialidade. O estudo parte do pressuposto de que a escola sozinha nÃo à capaz de desenvolver integralmente seus alunos. Trata-se de uma pesquisa avaliativa, com abordagem qualitativa, que buscou contemplar a voz dos diversos sujeitos por meio de entrevistas e grupos focais, que foram determinantes para a coleta de dados. Possibilitou perceber as aÃÃes do Programa para a construÃÃo de uma prÃtica intersetorial. / A presente pesquisa tem no objeto de estudo o Programa Mais EducaÃÃo, polÃtica pÃblica de educaÃÃo integral, atravÃs a ampliaÃÃo dos tempos e espaÃos de aprendizagem, instituÃda pelo MinistÃrio da EducaÃÃo (MEC). O estudo tem como objetivo principal avaliar o processo de implementaÃÃo do programa, atravÃs do estudo de investigaÃÃo em uma escola pÃblica do municÃpio de Fortaleza â CE. Para tanto escolhemos como lÃcus a Escola Municipal Casimiro Montenegro. Estudamos diferentes concepÃÃes e prÃticas de educaÃÃo integral, encontrado em autores como: AnÃsio Teixeira (1962), Paulo Freire (1968), Guarà (2006), Cavaliere (2000), dentre outros que fundamentaram a investigaÃÃo. Refletimos sobre as concepÃÃes de educaÃÃo integral presentes nos sujeitos envolvidos e analisamos o cotidiano escolar e as repercussÃes decorrentes do Programa Mais EducaÃÃo na comunidade local, e relacionamos, ainda, com a intersetorialidade. O estudo parte do pressuposto de que a escola sozinha nÃo à capaz de desenvolver integralmente seus alunos. Trata-se de uma pesquisa avaliativa, com abordagem qualitativa, que buscou contemplar a voz dos diversos sujeitos por meio de entrevistas e grupos focais, que foram determinantes para a coleta de dados. Possibilitou perceber as aÃÃes do Programa para a construÃÃo de uma prÃtica intersetorial. / The object of study in this research is the More Education Program, a public policy of comprehensive education through expansion of the times and places of learning established by the Ministry of Education (MEC). The study aims at evaluating the implementation process of the program, through the research study in a public school in Fortaleza - CE, therefore chosen as the locus Municipal School Casimiro Montenegro. We study different concepts and practices of holistic education, found in authors such as: Teixeira (1962), Paulo Freire (1968), Guara (2006), Cavaliere (2000), among others which motivated the research. We reflect on the concepts of comprehensive education present in subjects involved and analyze the school routine and the repercussion of More Education Program in the local community, and also relate to the intersectionality. The study assumes that the school alone can not fully develop their students. It is an evaluative study with a qualitative approach, which sought to include the voice of many subjects through interviews and focus groups, which were instrumental in data collection. It enabled to perceive the actions of the Program for the building of an intersectoral practice. / The object of study in this research is the More Education Program, a public policy of comprehensive education through expansion of the times and places of learning established by the Ministry of Education (MEC). The study aims at evaluating the implementation process of the program, through the research study in a public school in Fortaleza - CE, therefore chosen as the locus Municipal School Casimiro Montenegro. We study different concepts and practices of holistic education, found in authors such as: Teixeira (1962), Paulo Freire (1968), Guara (2006), Cavaliere (2000), among others which motivated the research. We reflect on the concepts of comprehensive education present in subjects involved and analyze the school routine and the repercussion of More Education Program in the local community, and also relate to the intersectionality. The study assumes that the school alone can not fully develop their students. It is an evaluative study with a qualitative approach,which sought to include the voice of many subjects through interviews and focus groups, which were instrumental in data collection. It enabled to perceive the actions of the Program for the building of an intersectoral practice.
249

The Fall Into Modernity

Douglas, Nigel Charles 05 1900 (has links)
Permission from the author to digitize this work is pending. Please contact the ICS library if you would like to view this work.
250

"Můj děsivý stín, jenž mne stále provází": Literární a umělecké zobrazení Richarda III před Shakespearem / "My fearefull shadow that still followes me": Literary and Artistic Representations of Richard III before Shakespeare

Štollová, Jitka January 2013 (has links)
THESIS ABSTRACT This MA thesis examines the portrayal of King Richard III (1452-1485) in texts preceding William Shakespeare's canonical play on this subject. By analyzing a wide range of sources written between the 1480s and the 1590s, it traces how the reputation of Richard III as an epitome of a tyrant, a usurper and a royal murderer was created and consolidated. At the same time, special attention is paid to innovations and deviations from this interpretation that contributed to the diversification of the King's image. The first chapter covers some of the most significant historiographic works of the Tudor era: The Second Continuation of The Crowland Chronicle, chronicles by Polydore Vergil, Edward Hall, and Raphael Holinshed, Thomas More's historical narrative, as well as a less-known manuscript by Dominic Mancini who described the early months of the reign of Richard III. The second chapter examines the transformation of the historical topic into poetry. The image of Richard III is analyzed in as diverse sources as, on the one hand, a popular ballad and, on the other hand, a prominent poetically-didactic work A Mirror for Magistrates. The representation of Richard III on the English stage is discussed in the third chapter in connection with Thomas Legge's university drama Richardus Tertius and the...

Page generated in 0.0258 seconds