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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.
31

Electric conversion of combustion engine cars / Elkonvertering av bilar med förbränningsmotor

Modling, Annika, Åbrandt, Bobby January 2022 (has links)
The electrification of personal transport vehicles is one of the strategies to counteract global warming and dependance on fossil fuels. Diesel powered cars are already prohibited in several big cities and the prices for fuel are constantly climbing. Even so, electric cars are still a premium that not everyone can afford as they could an older ICE-car. This means that there can be a gap in the near future were the Swedish working- and middle class can neither afford a new EV nor refuel their combustion engine car. This thesis investigates the possibilities and challenges of electric conversion of an existing, (used) combustion engine car as an alternative to buying a new electric car. The conversion is meant to be a DIY-project that can be carried out by anyone with the capacity to learn all the skills necessary and with sufficient funds to own a car in the first place. Parts of or the whole project can be outsourced to machine shops or similar, if there are areas where knowledge or equipment of the builder are insufficient. This type of conversion proves to be highly modular where the selection of both car and components depends on budget, time, and knowledge. Brushed DC motors offer reliability at a low cost, but with relatively low efficiency. A three-phase induction motor will be a more costly option, but with the benefit of higher efficiency and power. The batteries that are deemed appropriate for the conversion are lead-acid and lithium-ion batteries. Lead-acid batteries are robust and have a low cost. Their low energy density will however result in a higher weight making this type of battery best suited for a small car with short range. Lithium-ion batteries, which are used in commercial EVs, have a high energy density and lower weight. They come at a high cost however, and they require individual monitoring of the cells’ voltage to prevent potential failure. The converted car will have to be registered as a modified vehicle in order to legally be used in Sweden. The original total weight of the car cannot be exceeded during the conversion and because of this, a car with low curb weight and high max load is preferable as a starting point. / Den pågående elektrifieringen av personlig transport är ett av verktygen för att uppnå en hållbar utveckling. I samband med detta stiger bränslepriser och förbud mot dieseldrivna bilar finns numera i flertalet städer. Trots detta är elbilar fortfarande mycket dyra i inköp. Elkonvertering av befintliga (begagnade) bilar kan vara både ekonomiskt och ekologiskt gynnsamt då resultatet blir en cirkulär ekonomi och minskat behov av fossila bränslen, samtidigt som bilägaren ej behöver betala för dyrt bränsle. Detta examensarbete kartlägger möjligheterna och utmaningarna kring elkonvertering av enbegagnad bil med förbränningsmotor som alternativ för att köpa en ny elektrisk bil. Konverteringen skall vara ett DIY-projekt som kan genomföras av alla som har kapaciteten att lära sig de färdigheter som krävs samt har finansiella möjlighten att äga en bil. Delar av eller hela arbetet kan även lämnas bort till en mekanisk verkstad om byggaren saknar kunskap eller utrustningen för att genomföra projektet. Att utföra en sådan konvertering visar sig vara högst modulärt där val av bil eller komponenter behöver fattas utifrån budget, tid och kunskap. Kolborst-DC motorer erbjuder pålitlighet till ett lågt pris men har förhållandevis låg verkningsgrad. Trefas AC motorer innebär högre kostnad men erbjuder högre effektivitet och mer effekt. De batterier som bedöms lämpliga för konverteringen är bly-syra batterier och litium-jonbatterier. Även här skiljer sig kostnad och prestanda. Bly-syrabatterier är robusta och innebär lägre kostnad, men har låg energidensitet och resulterar i hög vikt. De lämpar sig därför för mindre bilar med kort räckvidd. Litium-jonbatterier, som används kommersiellt i dagens elbilar, har hög energidensitet och lägre vikt. De är dock ett mer kostsamt alternativ och kräver cellövervakning för att förhindra potentiellt haveri. Bilen kommer behövas registreras som ombyggt fordon för att lagligt kunna brukas i Sverige. Viktigt är att bilens ursprungliga totalvikt ej överskrids, varför en bil med låg tjänstevikt och hög maxlast är att föredra som utgångspunkt för konverteringen.
32

Klippt & skuret : En studie av butikens påverkan till Do-It-Yourself-aktiviteter med textila metervaror

Petersson, Emil, Strandman, Julia January 2016 (has links)
Interior textiles have been a part of the everyday life of humans for hundreds of years, especially for women whom the creation of textiles has been a usual feature. Archeological findings from the 16th century B.C. show that tools for spinning and weaving for home usage were a part of every household. This was common until the 19th century, when the industrialization in Europe took off and the first textile industries began to establish. This was the beginning of big changes to the modern man’s lifestyle and the way we consume interior textiles. As mass produced products have taken over the market, a counter-reaction among consumers have emerged. The consumers feel a bigger need for unique products, products that feel meaningful for themselves or in any other way increases the perceived value. This has led to a growing trend for DIY-activities (Do-It-Yourself). While the sales of DIY-related products and interior design products increases, statistics shows a decrease in the sales of textile meter fabrics, which is a raw material aimed to be used for interior design and DIY-projects. It can be identified by the way that businesses are selling textile meter fabrics that the strategies haven’t changed very much in the recent decades. Therefore, it is questionable whether the meter fabric assortment is on its way to extinction or if the offer needs to change to better suit the customers’ requirements. This study has focused on what elements of the textile meter fabric offer could be changed in a store in Germany. An analysis of a selective sample of the German customer and how they use textile meter fabrics has been made, but also on how they perceive the offer in store and what they wish to be changed in the textile meter fabrics department. The interviews were conducted in an anonymous store in Frankfurt, Germany. The empirical findings have been put in relation with studies of DIY-motivations and shopping experience. An interview with a sales leader of one of the leading stores of home textiles in Germany, including meter fabrics, has been done in order to put the customers’ answers in relation to how the store work with increasing the DIY-motivations towards the customers. The study has resulted in insights about the stores lacking ability to provide the customers with enough motivation for DIY-projects in regards to textile meter fabrics. A disconnection between the vision of the store and the customers’ perception of the offer has been discovered, where the possibilities of improvement are vast. The study also shows that a majority of the interviewed German males show little or no interest in both DIY and textile meter fabrics.
33

DIY Feminism in Post-Industrial Spaces

John T Sherrill (6864797) 02 August 2019 (has links)
Situating makerspaces as an extension of post-industrial economies, and sites where technical communication and craftivism take place, this dissertation builds on critiques of makerspaces as hobbyist spaces that privilege digital electronics, populated mostly by white men. To do so, this dissertation analyzes who participates in feminist makerspaces, how “makers” describe their work and their experiences, and the roles of rhetoric and technical communication within feminist makerspaces. Building on prior studies of maker communities, this research follows a mixed methods approach and an iterative methodology, including online survey, site studies, interviews, and on-site automated survey to collect user data via kiosk. The online survey asked participants to describe makerspaces they’ve visited, their experiences visiting makerspaces, their work, and themselves. Follow-up interviews conducted with three survey participants addressed times participants felt unwelcome or out of place in a makerspace. Additionally, site studies consisted of visiting and observing two Midwestern makerspaces, both of which partnered with public libraries. This dissertation argues that makerspaces need to do a better job of welcoming guests and new members and actively hosting social events, rather than passively marketing workshops focused on specific technologies. Although people are becoming more familiar with makerspaces, regardless of gender and other aspects of identity, participants describe social anxieties about entering new spaces and unfamiliar communities as common barriers to entry, even before encountering issues based on gender, race, and other aspects of identity. If makerspaces (and “maker” communities more broadly) aim to be more inclusive and equitable, then actively welcoming people in general is a necessary baseline. As such, this dissertation draws from rhetorical theory to suggest ways that makerspaces can improve their hospitality and technical communication practices.
34

From Do It Yourself to Do It Together : Sociological analysis of knowledge sharing in Stockholm Makerspace

Shmidt, Mayya January 2019 (has links)
The study examinesthe variety of interaction and motivation practices to participate in the sharing initiative as well as pinpointing key elements of member-driven organization functioning;in the case of Stockholm Makerspace– a community of non-professional makers.  The Current scholarship on sharing is mostly focused on the large-scale platform businesses in a North American context, thus evidence from grassroots small-scale initiatives is lacking. This paper aims to fill this gap by providing the empirically grounded sociological study of the operation of sharing initiative in Sweden. Data including 1) 11 in-depth interviews conducted with active members of the community and experts, 2) ethnographic observation in situations of planned workshops and everyday life of the Makerspace, 3) systematic online observation (in the role of observer as participant) (Gold, 1958). Therefore, this study employs mixed ethnography and digital methodology – studying sharing economy communities both online and in situto provide a ‘thick’ description of community building. The results revealed that members of the Stockholm Makerspace, acted as prosumers, and attempted to benefit not only from the community understudy, but also contributed to the societal development at large, by creating a public good. Shared access to tools and common “know-how” democratized production of knowledge and its spreading, thus contributing to informal learning, which complemented formal education institutions. The main incentives of sharing, vocalized by participants in the study were open-ended socializing and community commitment, as well as self-expression and belonging.
35

spiritualize materia : blunda och stryk handen över materialet, det är nog krokodil

Öman, Robinne January 2019 (has links)
No description available.
36

UMBANDA, UMA RELIGIÃO SINCRÉTICA E BRASILEIRA. / Umbanda, a syncretic and Brazilian religion.

Costa, Hulda Silva Cedro da 19 December 2013 (has links)
Made available in DSpace on 2016-07-27T13:46:27Z (GMT). No. of bitstreams: 1 HULDA SILVA CEDRO DA COSTA.pdf: 2734160 bytes, checksum: a0146805d81523745399983125973f20 (MD5) Previous issue date: 2013-12-19 / This thesis analyzes the Umbanda religion and its consolidated training process through a continuous syncretism that began in the late 17th Century, with the first black religious communities, mostly Bantu s origin. This formation process of Umbanda presented four phases. The first one began with the Calundu, in the 17th Century, advancing to Cabula, in the early 19th Century, the Macumba, in the middle of this same century, resulting in Umbanda, which emerged in the early 20th century, and has become the fourth phase of this syncretic religious and continuous process. The research is intended to open a discussion about the formation process of the structural basis of The Umbanda Religion, which origin comes from the fusion of several elements of African origin, the Spiritualism of Kardecista, the elements of indigenous origin and even the elements of Catholicism. This way, it characterizes a highly syncretic process, and because of its approach to Christianity, a significant separation from its African headquarters occurred. Nowadays, some theorists do not want to use the term syncretism, relating it to situations of domination, as something impure, and therefore, relegated as a negative term, considered a pejorative concept, such as bringing in its essence, a conception of the mixture, thus denying the originality and identity of the African s descent people. Thus, some researchers prefer to use the terms hybridity and bricolage(DIY), stating that these terms are different from the term syncretism. As a result of this debate, we can clearly identify in which parts of the discussion these authors either match or differ in their points of view, and how different and distant they are in their theories about these terms, in order to verify the applicability of the Umbanda Religion. We approach the search process of its legitimation as a Brazilian Umbanda religion, and to be accepted by the ruling class. Accordingly, we analyze its passage by the Vargas era, its relationship with the Catholic Church and the military dictatorship, when it reached its zenith. We analyzed its precipitous decline, from the 1980s on, with the growth of neo- Pentecostal movements. Since then, the Umbanda has been in decline, but revived in the 21st. century, represented by three major religious segments namely: Initiative Umbanda, Holy Umbanda and Cross Line Umbanda. / A presente tese analisa a religião Umbanda e seu processo de formação consolidado por meio de um sincretismo contínuo que teve início no final do século XVII, com as primeiras comunidades religiosas negras, em sua grande maioria de origem banto. Esse processo formador da Umbanda apresentou quatro fases. A primeira, se iniciou com o Calundu, no século XVII, perpassando pela Cabula, no início do século XIX, pela Macumba, em meados deste mesmo século, resultando na Umbanda, que surgiu no início do século XX, e se constituiu a quarta fase deste processo religioso sincrético e contínuo. A pesquisa tem a finalidade de abrir uma discussão acerca do processo formador da base estrutural da religião Umbanda, que nasceu da fusão de vários elementos de origem africana, do Espiritismo Kardecista, de elementos de origem indígena e ainda de elementos advindos do catolicismo, caracterizando dessa forma, um processo altamente sincrético, e por causa da sua aproximação com o cristianismo, ocorreu um afastamento significativo de suas matrizes africanas. Atualmente, alguns teóricos não querem utilizar o termo sincretismo, relacionando-o às situações de dominação, como se fosse algo impuro, sendo, portanto, relegado como um termo negativo, considerado um conceito pejorativo, no sentido de que ele poderia trazer em seu bojo uma concepção de mistura, negando assim a originalidade e a identidade dos povos afro descendentes. Assim, alguns pesquisadores preferem utilizar os termos hibridismo e bricolagem, afirmando que esses termos são diferentes do termo sincretismo. Diante desse debate, verificamos onde esses diferentes autores se encontram e onde se distanciam em suas teorizações acerca desses termos, para verificar a aplicabilidade na religião Umbanda. Abordamos o processo de busca de legitimação da Umbanda como uma religião brasileira, e para ser aceita pela classe dominante. Nesse sentido, analisamos a sua passagem pela era Vargas, sua relação com a igreja católica e com o regime militar, momento este último, que lhe proporcionou vivenciar o seu apogeu. E analisamos a sua queda vertiginosa, a partir dos anos de 1980, com o crescimento dos movimentos neopentecostais. A partir daí, a Umbanda entrou em declínio, mas ressurgiu no século XXI, representada por três grandes segmentos religiosos a saber: a Umbanda Iniciática, a Umbanda Sagrada e a Linha Cruzada.
37

Arquitetura e implementação aberta de um sintetizador subtrativo e aditivo para platafroma de baixo custo / An open design and implementation of a subtractive and additive synthesizer for low cost platforms

Pirotti, Rodolfo Pedó January 2017 (has links)
Existem inúmeras técnicas de síntese de áudio utilizadas atualmente em instrumentos musicais profissionais, dentre as quais as mais fundamentais são a síntese aditiva e a síntese subtrativa. A síntese subtrativa se tornou popular e foi muito explorada entre as décadas de 60 e 70 com a criação de módulos analógicos de hardware que podiam ser interconectados, criando o conceito de sintetizador analógico modular. Apesar do uso deste tipo de sintetizador ter diminuído durante as décadas subsequentes, nos últimos anos sua utilização voltou a crescer e diversos modelos deste tipo de instrumento são vendidos atualmente, porém em geral a preços elevados. Sintetizadores digitais também disponibilizam a técnica de síntese subtrativa utilizando componentes eletrônicos customizados e desenvolvidos pelos fabricantes de sintetizadores com o intuito de utilizar avançadas técnicas de processamento de sinais, o que ainda mantém seus preços elevados. Neste trabalho investigamos a hipótese de que é possível desenvolver um instrumento musical funcional e de qualidade com recursos limitados de processamento, e exploramos essa hipótese implementando síntese subtrativa em uma plataforma acessível e de baixo custo. O desenvolvimento é baseado em linguagem orientada a objetos para criação de módulos de software replicando as características dos módulos encontrados em sintetizadores analógicos modulares. Com esta abordagem, obtemos um software modular que pode ser facilmente modificado baseado nas preferências do programador. A implementação foi testada na plataforma Arduino Due, que é uma plataforma de baixo custo e contém um processador 32-bits ARM 84 MHz. Foi possível adicionar osciladores com algoritmo anti-aliasing, filtros, geradores de envelope, módulo de efeito, uma interface MIDI e um teclado externo, obtendo assim um sintetizador subtrativo completo. Além disto, incluímos no desenvolvimento a implementação de um órgão baseado em síntese aditiva, com polifonia completa e inspirado na arquitetura de órgãos clássicos, mostrando a possibilidade de possuir dois importantes e poderosos métodos de síntese em uma plataforma acessível e de baixo custo. Com esta implementação aberta e pública, buscamos contribuir com o movimento maker e faça-você-mesmo, incentivando novos desenvolvimentos nesta área, em especial na computação e engenharia, aumentando o uso e acesso a instrumentos musicais eletrônicos e a criatividade musical. / Subtractive and additive synthesis are two powerful sound synthesis techniques that caused a revolution when the first electronic and electro mechanic music instruments started to appear some decades ago. Subtractive synthesis became very popular during the 60s and 70s after the creation of analog hardware modules that could be interconnected, creating the concept of the modular synthesizers. After the initial impact, for some years these instruments faced a slow-down in its usage, a tendency that was reverted on the past decade. Nevertheless, the prices of these instruments are often high. Digital synthesizers also offer the subtractive synthesis technique, by using customized electronic components designed and developed by the synthesizers vendors in order to use the most up-to-date technologies and signal processing techniques, which also leads to high prices. In this project, we investigate the hypothesis that it is possible to design and develop a good quality music instrument with low budget electronic components and limited processing capabilities, by implementing this on a low budget and easy to use platform. The development is based on object oriented design, creating software modules that replicates the functionalities of analog synthesizer hardware modules. With this approach, we have a modular software that can be easily changed based on programmers’ preferences. The implementation was tested on the Arduino Due board, which is a cheap, easy to use and widely available platform and powered by a 32-bits ARM 84Mhz processor. We were able to add oscillators with anti-aliasing algorithms, filters, envelope generators, delay effects, a MIDI interface and a keybed, making a complete synthesizer. In addition to this, we included an additive synthesis organ design with full polyphony based on classic organs design, demonstrating the possibility of having two powerful synthesis methods on a cheap and widely available platform. With this design, suitable for low cost platforms, we intend to contribute to the maker movement and encourage new implementations in this area, especially in the computing and engineering fields, increasing the usage and access to (electronic) musical instruments and musical creativity.
38

3D Printing: Convergences, Frictions, Fluidity

Ree, Robert 19 December 2011 (has links)
The emergence of desktop ‘3D printing’ is not only a technological development, but equally a social and economic phenomenon that actively (and often contentiously) co-produces the material and ideological infrastructures it occupies. Reflecting wider momentum toward digital-material convergence, the current “revolution” in desktop digital fabrication is fundamentally attributable to the efforts of decentralized Maker and DIY communities who, connected through digital networks, practice citizen-led technological experimentation and occupy novel spaces for innovation and entrepreneurship. Employing hybrid qualitative methods that include Critical Making, this research explores the following themes: rhetoric versus reality, the divisive notion of ‘digital craft’, perceptions of authenticity, as well as cultural momentum manifested in decentralization, convergence, stratification, and iteration. An overarching theme emerges: 3D printing is a fluid phenomenon – in literal, metaphorical, technological and cultural ways.
39

3D Printing: Convergences, Frictions, Fluidity

Ree, Robert 19 December 2011 (has links)
The emergence of desktop ‘3D printing’ is not only a technological development, but equally a social and economic phenomenon that actively (and often contentiously) co-produces the material and ideological infrastructures it occupies. Reflecting wider momentum toward digital-material convergence, the current “revolution” in desktop digital fabrication is fundamentally attributable to the efforts of decentralized Maker and DIY communities who, connected through digital networks, practice citizen-led technological experimentation and occupy novel spaces for innovation and entrepreneurship. Employing hybrid qualitative methods that include Critical Making, this research explores the following themes: rhetoric versus reality, the divisive notion of ‘digital craft’, perceptions of authenticity, as well as cultural momentum manifested in decentralization, convergence, stratification, and iteration. An overarching theme emerges: 3D printing is a fluid phenomenon – in literal, metaphorical, technological and cultural ways.
40

Ampiify : Opening oportunities on outdated electronics

Oko Mambo-Matala, Ngatye-Brian January 2012 (has links)
The disposal of electronic waste is becoming one of the growing problems that the planet is facing. Tons of electronic waste is dumped illegally to 3rd world countries. Consequently the local people in those countries are exposed to levels of toxicity that could cause them serious diseases as well as the degradation on the natural ecosystems. The electronic waste is perceived as useless by our society, and this project aims to challenge that idea by looking at sustainable ways of manipulating electronics.

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