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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.
921

Latt-Mayer, um estudo de caso: tecnologia na história do design gráfico brasileiro. / Latt-Mayer, a case study: technology in the history of Brazilian graphic design

Almir Mirabeau da Fonseca Neto 01 September 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Nosso objetivo neste trabalho é investigar como o design gráfico se relaciona com os meios de produção da indústria gráfica brasileira. Não é comum encontrar referências abordando temas que relacionam design e tecnologia em livros sobre a história do Brasil, o que demonstra a urgência do resgate histórico de indústrias que implementaram novas tecnologias para atender a demandas projetuais e mercadológicas. Sediada na cidade do Rio de Janeiro, a clicheria Latt-Mayer como era comumente chamada, era sinônimo de qualidade e tecnologia. Entre seus clientes podemos apontar agências de publicidade, editoras, escritórios de designers e gráficas de todo país. Esta pesquisa se baseia em um corpus composto por imagens, documentos, manuais técnicos, reportagens, matrizes e depoimentos com pessoas que estiveram diretamente envolvidas com essa empresa. Catalogamos maquinaria e técnicas utilizadas, além de projetos gráficos relevantes que tiveram matrizes e provas produzidas na empresa. Por meio deste trabalho, é possível visualizar um abrangente painel histórico, que contempla um período em que ocorreram significativas transformações na relação entre designers e tecnologia na indústria gráfica brasileira. / Our purpose in this research is to investigate how the graphic design relates to the means of production in the Brazilian printing industry. It is unusual to find references on topics that relate design & technology in books on Brazilian history, which demonstrates the need to recapture the history of industries that have implemented new technology to answer design and market demands. Located in Rio de Janeiro, the photoengraving shop Latt-Mayer as it was commonly called, was synonymous with high quality and technological advance. Among its clients we can point to advertising agencies, publishers, design offices and the printing industry across the country. This research is based on a corpus consisting of images, documents, technical manuals, reports, and interviews with people who were directly involved with the company. We have cataloged machinery and techniques used and graphic design relevant to their patterns and had printing proofs produced by the engraving shop. With this work, we can observe a comprehensive historical panel, which includes a period in which there were significant overall changes in the relation between technology & design in the Brazilian printing industry.
922

Design de superfície : um estudo sobre a aplicação do termocromismo em camisetas

Pippi, Luis Fernando Aita January 2010 (has links)
O estudo busca esclarecer pontos essenciais sobre o emprego da termocromia em têxteis por meio de sua aplicação em estampas em camisetas, respondendo questões sobre o poder expressivo destas e do uso da termocromia como recurso de qualificação em projetos de Design de Superfície. A pesquisa traz dados históricos da camiseta como objeto de design e moda. Nesse contexto verificou-se a relevância dos esclarecimentos técnicos sobre o funcionamento da tinta termocrômica, assim como apresenta-se no estudo uma gama de produtos que se utilizaram da aplicação desta técnica, além de estudos acadêmicos considerados inovadores nessa área de conhecimento. O objetivo principal do estudo é explorar novos conhecimentos sobre os sistemas e técnicas em relação à aplicabilidade da termocromia em estampas de camisetas, bem como mostrar as capacidades subjetivas de comunicação/expressão e de interatividade em produtos com essa tecnologia, que podem servir como auxílio para os designers em projetos inovadores. Neste sentido, foram propostos estudos experimentais de aplicação de estampas com tinta termocrômica em camisetas, que deram o sentido fundamental a esta dissertação, acrescentando conhecimento e abrindo espaço para novas pesquisas no âmbito interdisciplinar. Neste estudo de caso exploratório, foi possível concluir, que os métodos mostrados aqui são fatores importantes de inovação para o setor têxtil e de moda e que os testes produzidos provaram a necessidade de rigor técnico contido nas especificações técnicas do fornecedor. / This study aims to clarify some fundamental questions related to textile thermochromism in the application of t-shirt printing, namely the expressive power of prints and the use of thermochromism as a resource in surface design. The investigation brings historical data regarding the t-shirt as an object of design and fashion. In this context, the importance of technical clarification related to the performance of thermochromic ink is verified and a range of products utilized in this technique are presented. A number of innovative academic studies in this area are also presented. The main objectives of this study are to investigate new knowledge about the applicability of systems and techniques utilized in thermochromic t-shirt graphics and to demonstrate the subjective capacity of expression and interaction of products that utilize this technology, which can serve as an aid to designers in innovative projects. From this perspective, experimental tests in the application of thermochromic t-shirt printing were proposed, providing significance to this thesis, enhancing the knowledge in this field and promoting further interdisciplinary research. In this exploratory case study it was possible to conclude that the methods shown here represent important innovations in the textile and fashion sectors and that the tests demonstrated the necessity of technical rigor regarding manufacturers’ technical specifications.
923

Material analysis of wearabale hyperthermia applicator

Ramasamy, Manoshika January 1900 (has links)
Master of Science / Department of Apparel, Textiles, and Interior Design / Minyoung Suh / The purpose of this study was to explore printed antennas as an alternative technique for applying hyperthermia treatment. The antenna consisted of a printed ground plane and a thin copper plate. The ground plane was made of silver conductive ink printed on a flexible substrate. The challenge of the printed ground plane was limited conductivity. Multi-layer printing was one of the ways to increase the conductivity of the printed trace. This study examined whether the multiple-layered printings on the ground plane influence the performance of the antenna. The ground plane printed on a flexible substrate was evaluated for its conductivity and capacity to handle the heat energy for the extended time duration at the elevated temperature. This research was conducted in two experimental stages. The first stage of the experiment was designed to test conductivity of the ground plane. Ground planes were printed on a 32.5 mm × 17.0 mm substrate. The thickness and resistance of up to five layers of conductive printing were tested to verify how repeated printing improved the resistance and resistivity. Results showed that the multi-layering technique reduced the resistance of the printed trace, but statistically, the ground plane had no significant improvement in resistance beyond the triple layer printing. With an increase of the thickness, resistivity rather increased after the triple layer printing. The second stage of the experiment was used to assess the performance of the entire antenna. Antennas were fabricated using ground planes with triple and quintuple layers based on resistance and resistivity measurements. The antennas showed an acceptable level of performance in terms of antenna return loss and temperature elevation. The statistical analysis of return loss, power handling capability over the time, and temperature elevation was not significant among the antennas with triple and quintuple layered ground planes. Antennas were able to achieve 42 ˚C within 10 minutes at a 2cm deep location with the return loss of -13.76 dB. Most importantly, experimental results showed that antennas were able to handle 15 watt power without degrading the antenna performance. The antenna showed a successful performance in power handling and reaching the tumor temperature.
924

Effect of non-parallel applicator insertion on microwave ablation zone size and shape

White, Austin January 1900 (has links)
Master of Science / Department of Electrical and Computer Engineering / Punit Prakash / Microwave ablation is clinically used to thermally ablate cancerous tissue in the liver and other organs. When treating large tumor volumes, physicians may use multiple antennas simultaneously. Multiple antennas can ablate a larger tissue volume while using the same total power as a single antenna. Pre-clinical simulation and experimental studies most often presume parallel insertion of antennas. However, due to anatomical constraints, such as the presence of ribs and the diaphragm, it is often challenging to insert antennas in a parallel fashion in practice. Previous studies have attempted to analyze the effect of non-parallel antenna insertion on ablation outcome using computational and experimental approaches; however, they were limited because they did not account for dynamic temperature-dependent changes in tissue electrical properties in simulations and employed limited experimental validation. In this thesis, we have developed improved models of multiple-antenna microwave ablation, including accounting for the effects of temperature-dependent changes in tissue properties. We have also developed a system for experimental assessment of ablation zone profiles in ex vivo tissues. By utilizing 3D printing, we have constructed a device to precisely position antennas within experimental tissue samples and allows for accurate sectioning of the ablation zone relative to the plane of antenna insertion. Furthermore, we implemented image processing techniques for quantifying the size and shape of experimental ablation zones. This enables more accurate and repeatable comparisons of ablation profiles between simulations and experiments. We found that for an inter-antenna spacing in the range of 10 – 20 mm, simulations and experiments indicated that the ablation zone volumes may change by up to 30% due to non-parallel antenna insertion.
925

Three Dimensional Printing and Computational Visualization for Surgical Planning and Medical Education

January 2015 (has links)
abstract: The advent of medical imaging has enabled significant advances in pre-procedural planning, allowing cardiovascular anatomy to be visualized noninvasively before a procedure. However, absolute scale and tactile information are not conveyed in traditional pre-procedural planning based on images alone. This information deficit fails to completely prepare clinicians for complex heart repair, where surgeons must consider the varied presentations of cardiac morphology and malformations. Three-dimensional (3D) visualization and 3D printing provide a mechanism to construct patient-specific, scale models of cardiovascular anatomy that surgeons and interventionalists can examine prior to a procedure. In addition, the same patient-specific models provide a valuable resource for educating future medical professionals. Instead of looking at idealized images on a computer screen or pages from medical textbooks, medical students can review a life-like model of patient anatomy. In cases where surgical repair is insufficient to return the heart to normal function, a patient may proceed to advanced heart failure, and a heart transplant may be required. Unfortunately, a finite number of available donor hearts are available. A mechanical circulatory support (MCS) device can be used to bridge the time between heart failure and reception of a donor heart. These MCS devices are typically constructed for the adult population. Accordingly, the size associated to the device is a limiting factor for small adults or pediatric patients who often have smaller thoracic measurements. While current eligibility criteria are based on correlative measurements, the aforementioned 3D visualization capabilities can be leveraged to accomplish patient-specific fit analysis. The main objectives of the work presented in this dissertation were 1) to develop and evaluate an optimized process for 3D printing cardiovascular anatomy for surgical planning and medical education and 2) to develop and evaluate computational tools to assess MCS device fit in specific patients. The evaluations for objectives 1 and 2 were completed with a collection of qualitative and quantitative validations. These validations include case studies to illustrate meaningful, qualitative results as well as quantitative results from surgical outcomes. The latter results present the first quantitative supporting evidence, beyond anecdotal case studies, regarding the efficacy of 3D printing for pre-procedural planning; this data is suitable as pilot data for clinical trials. The products of this work were used to plan 200 cardiovascular procedures (including 79 cardiothoracic surgeries at Phoenix Children's Hospital), via 3D printed heart models and assess MCS device fit in 29 patients across 6 countries. / Dissertation/Thesis / Doctoral Dissertation Bioengineering 2015
926

Microstructure Development in Direct Metal Laser Sintered Inconel Alloy 718

January 2017 (has links)
abstract: The microstructure development of Inconel alloy 718 (IN718) during conventional processing has been extensively studied and much has been discovered as to the mechanisms behind the exceptional creep resistance that the alloy exhibits. More recently with the development of large scale 3D printing of alloys such as IN718 a new dimension of complexity has emerged in the understanding of alloy microstructure development, hence, potential alloy development opportunity for IN718. This study is a broad stroke at discovering possible alternate microstructures developing in Direct-Metal-Laser-Sintering (DMLS) processed IN718 compared to those in conventional wrought IN718. The main inspiration for this study came from creep test results from several DMLS IN718 samples at Honeywell that showed a significant improvement in creep capabilities for DMLS718 compared to cast and wrought IN718 (Honeywell). From this data the steady-state creep rates were evaluated and fitted to current creep models in order to identify active creep mechanisms in conventional and DMLS IN718 and illuminate the potential factors responsible for the improved creep behavior in DMSL processed IN718. Because rapid heating and cooling can introduce high internal stress and impact microstructural development, such as gamma double prime formations (Oblak et al.), leading to differences in material behavior, DMLS and conventional IN718 materials are studied using SEM and TEM characterization to investigate sub-micron and/or nano-scale microstructural differences developed in the DMLS samples as a result of their complex thermal history and internal stress. The preliminary analysis presented in this body of work is an attempt to better understand the effect of DMLS processing in quest for development of optimization techniques for DMLS as a whole. A historical sketch of nickel alloys and the development of IN718 is given. A literature review detailing the microstructure of IN718 is presented. Creep data analysis and identification of active creep mechanisms are evaluated. High-resolution microstructural characterization of DMLS and wrought IN718 are discussed in detail throughout various chapters of this thesis. Finally, an initial effort in developing a processing model that would allow for parameter optimization is presented. / Dissertation/Thesis / Masters Thesis Engineering 2017
927

Inorganic and Organic Photovoltaic Materials for Powering Electrochromic Systems

January 2018 (has links)
abstract: ABSTRACT Autonomous smart windows may be integrated with a stack of active components, such as electrochromic devices, to modulate the opacity/transparency by an applied voltage. Here, we describe the processing and performance of two classes of visibly-transparent photovoltaic materials, namely inorganic (ZnO thin film) and fully organic (PCDTBT:PC70BM), for integration with electrochromic stacks. Sputtered ZnO (2% Mn) films on ITO, with transparency in the visible range, were used to fabricate metal-semiconductor (MS), metal-insulator-semiconductor (MIS), and p-i-n heterojunction devices, and their photovoltaic conversion under ultraviolet (UV) illumination was evaluated with and without oxygen plasma-treated surface electrodes (Au, Ag, Al, and Ti/Ag). The MS Schottky parameters were fitted against the generalized Bardeen model to obtain the density of interface states (Dit ≈ 8.0×1011 eV−1cm−2) and neutral level (Eo ≈ -5.2 eV). These devices exhibited photoconductive behavior at λ = 365 nm, and low-noise Ag-ZnO detectors exhibited responsivity (R) and photoconductive gain (G) of 1.93×10−4 A/W and 6.57×10−4, respectively. Confirmed via matched-pair analysis, post-metallization, oxygen plasma treatment of Ag and Ti/Ag electrodes resulted in increased Schottky barrier heights, which maximized with a 2 nm SiO2 electron blocking layer (EBL), coupled with the suppression of recombination at the metal/semiconductor interface and blocking of majority carriers. For interdigitated devices under monochromatic UV-C illumination, the open-circuit voltage (Voc) was 1.2 V and short circuit current density (Jsc), due to minority carrier tunneling, was 0.68 mA/cm2. A fully organic bulk heterojunction photovoltaic device, composed of poly[N-9’-heptadecanyl-2,7-carbazole-alt-5,5-(4’,7’-di-2-thienyli2’,1’,3’-benzothiadiazole)]:phenyl-C71-butyric-acidmethyl (PCDTBT:PC70BM), with corresponding electron and hole transport layers, i.e., LiF with Al contact and conducting/non-conducting (nc) PEDOT:PSS (with ITO/PET or Ag nanowire/PDMS contacts; the illuminating side), respectively, was developed. The PCDTBT/PC70BM/PEDOT:PSS(nc)/ITO/PET stack exhibited the highest performance: power conversion efficiency (PCE) ≈ 3%, Voc = 0.9V, and Jsc ≈ 10-15 mA/cm2. These stacks exhibited high visible range transparency, and provided the requisite power for a switchable electrochromic stack having an inkjet-printed, optically-active layer of tungsten trioxide (WO3), peroxo-tungstic acid dihydrate, and titania (TiO2) nano-particle-based blend. The electrochromic stacks (i.e., PET/ITO/LiClO4/WO3 on ITO/PET and Ag nanowire/PDMS substrates) exhibited optical switching under external bias from the PV stack (or an electrical outlet), with 7 s coloration time, 8 s bleaching time, and 0.36-0.75 optical modulation at λ = 525 nm. The devices were paired using an Internet of Things controller that enabled wireless switching. / Dissertation/Thesis / Doctoral Dissertation Electrical Engineering 2018
928

Exoskeleton for hand rehabilitation

Martínez Conde, Sergio, Pérez Luque, Estela January 2018 (has links)
This document presents the development of a first proposal prototype of a rehabilitation exoskeleton hand. The idea was to create a lighter, less complex and cheaper exoskeleton than the existing models in the market but efficient enough to carry out rehabilitation therapies.The methodology implemented consists of an initial literature review followed by data collection resulting in a pre-design in two dimensions using two different software packages, MUMSA and WinmecC. First, MUMSA provides the parameters data of the movement of the hand to be done accurately. With these parameters, the mechanisms of each finger are designed using WinmecC. Once the errors were solved and the mechanism was achieved, the 3D model was designed.The final result is presented in two printed 3D models with different materials. The models perform a great accurate level on the motion replica of the fingers by using rotary servos. The properties of the model can change depending on the used material. ABS material gives a flexible prototype, and PLA material does not achieve it. The use of distinct methods to print has a high importance on the difficulties of development throughout the entire process of production. Despite found difficulties in the production, the model was printed successfully, obtaining a compact, strong, lightweight and eco-friendly with the environment prototype.
929

Marknadsundersökning kring additiv tillverkning i Sverige / Market research on Additive Manufacturing in Sweden

Tavajoh, Sara, Michael, Huynh January 2018 (has links)
Användningen och intresset för additiv tillverkning (AM) har ökat markant de senaste åren och det finns en teori kring att tillverkningsmetoden kan vara det nästa steget i den industriella revolutionen. Eftersom AM fortfarande befinner sig i utvecklingsstatidet går det att anta att tekniken ännu inte uppnått sin fulla potential och att det kan komma att finnas möjligheter att implementera tekniken i fler branscher och företag. Detta skulle innebära en bredare marknad för AM. Syftet med examensarbetet var att undersöka vilka möjligheter och hinder som finns för ökad användning av AM i Sverige. Studien genomfördes genom kvalitativa intervjuer med åtta olika verksamheter tillhörande den svenska industrin och en litteraturgenomgång för att presentera nuläget för AM i svensk industriell marknad. Resultatet av datainsamlingen analyserades med modellerna PEST, 4P och slutligen SWOT. De fördelar som har setts med användningen av AM har varit minskade ledtider, minskade kostnader för tillverkning av produkter och verktyg, minskat materialspill och en optimal designprocess med ökad kreativitet. De begränsningar som finns i tekniken i dagsläget är att priset för material och maskiner är dyrt. Vidare anses även kvalitet på slutdetalj, begränsad byggvolym och opålitliga processer vara problematiska. De möjligheter som finns beror huvudsakligen på den forskning som görs. Förutsättningarna för AM i svensk industri kommer att bero på hur tekniken kommer att utvecklas. De hinder som finns är kopplat till kompetensbrist och att det inte finns befintliga standarder för material eller process inom AM. / Within the industrial sector, an increased interest and usage of Additive Manufacturing (AM) throughout the decade has been formed. The layer-upon-layer building technology has been seen and recognized as one of the next industrial revolutionizing methods of production. As the technology is still in the trending and uprising phase it should be considered that its full potential has not yet been achieved, as large opportunities for implementation of AM exist and that new companies and markets have a growing interest in this technology. Through this study a market research was conducted to identify and present what opportunities and obstacles there are for an increased usage of AM in Sweden. A literature study on the Swedish market has been made to present the market as of today. Eight qualitative interviews have also been conducted with companies within the industrial sector to identify the areas of use within AM for production. The concepts and models used to analyze these questions was PEST, Marketing Mix and SWOT. The concluded results for advantages in using AM are shortened lead times, reduced costs of production of components and tools, reduced material waste and optimization of design processes with increased creativity. The concluded challenges are expensive materials and machine, the quality of finished components, limited printing volume due to the 3D-printers and reliability of printing processes. The finalized opportunities that are presented in this work are that AM is dependent on how much research on the subject and factors around it is done. How AM will be applied in the coming future revolves around the advancement in the technology. The obstacles that are found in this study are lack of competence and lack of standard for materials and processes within AM.
930

Através do espelho: a constituição da pintura inicial de Andy Warhol (1956-1968) / Through the mirror: the constitution of negginer paiting of Andy Warhol (1956-1968)

Tiago dos Santos Mesquita 26 June 2009 (has links)
Na década de60, Andy Warhol começou a trabalhar com as técnicas da serigrafia. Copiava imagens gráficas e fotográficas e as transferia diretamente para a tela. O artista abandonou os modos mais tradicionais de pintura e passou a trabalhar com a apropriação de imagens reproduzidas em série nos cartazes, fotografias, embalagens e no cinema. O uso destes clichês gráficos causou controvérsia. Uma série de discussões tentava entender a escolha do artista a partir de interlocuções dele com a obra de outros criadores e como uma interpretação de fatos da realidade social. A partir destas análises, este trabalho busca construir uma interpretação alternativa que entenda as razões para a modificação de procedimentos e linguagens na obra de Andy Warhol e o seu impacto na produção do século XX. / Andy Warhol started to work with the silkscreen techniques in the 1960s. Graphic and photographic images were copied and transferred straight onto canvas. The artist abandoned the traditional modes of painting and began working with the appropriation of serialized images from billboards, photos, packages and film. The use of such clichés was controversial. In several discussions, critics tried to understand Warhol\'s choices from his dialogue with other artists and as an interpretation of the facts of social reality. This study attempts to build an alternative interpretation that tries to understand the reasons for the modification of procedures and poetics in the Andy Warhol\'s work and his impact on the 20th century art.

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