Multi-material 3D Printing allows the ability to fabricate parts with tuned mechanical properties, multi-process 3D printing widens the choices of available fabrication materials. The objective of this study is to build a custom 3D printing test bed that is capable of printing multi-material parts with fused deposition modeling and direct ink writing techniques. A 3D printer, controlled by an industrial motion control system, with FDM and DIW capabilities was built by combining FDM extruders with a pneumatic dispensing system on a single platform. By utilizing the Direct Ink Writing function, we expand the number of printable materials to include some off the shelf silicones and epoxies, as well as custom, user made, materials. This study will further expand the manufacturing and research capabilities within the additive manufacturing discipline.

This thesis presents the implementation of some of the basic concepts of digital logic design in a fun and creative way with the help of paper electronics. This involves circuit building on paper using conductive tape or conductive ink and circuit components as electronics craft materials. Paper electronics toolkit called circuit sticker microcontroller which is deployed by a company named Chibitronics and AT89C51 microcontroller were used for the computational functioning of the circuits built on paper. This can be used to teach the fundamentals of digital logic design to the students in their early stage of studies in an attractive way and can help them them gain a better understanding. This thesis can also be helpful in grabbing the attention of high school students and motivate them towards choosing the engineering discipline for their higher studies.

Denna studie undersöker digitala läsvanor och läsplattor, ur ett människa-datorinteraktions perspektiv, för att bidra med insikter kring digital läsning genom att identifiera problem och utvecklingsområden hos läsplattan. En enkätundersökning genomfördes, där 947 svar erhölls. Intressentintervjuer, en expertintervju, samt användarintervjuer utfördes vidare för en djupare analys. Ur resultatet identifierades ”Köpprocess och synkronisering”, samt ”Bibliotekshantering och sortering” som två kritiska problemområden. Förslag på lösningar som formulerades var följande; automatisk synkronisering, förenklat betalningsmoment, vattenmärkta e- böcker, prenumerationstjänst med större utbud, förenklad process för att köpa böcker från olika leverantörer, bättre rekommendationsalgoritm, spelifiering, appen som utgångspunkt för synkronisering mot alla digitala enheter, sortering på lästa/olästa e- böcker, möjlighet att favoritmarkera e- böcker i biblioteket, samt ett layout- läge där endast boktiteln syns och ett stort antal böcker kan visas samtidigt. Vidare undersöktes läsplattans Product- Market Fit (PMF), genom att mäta produktens Net Promoter Score (NPS), samt hur många av användarna som hade blivit besvikna om läsplattan försvann och de inte kunde nyttja produkten längre. NPS beräknades till 41, vilket indikerar en god PMF. Vidare uppgav 71% av användarna, i enkäten, att de skulle bli ”Mycket besvikna” om läsplattan försvann, vilket antyder att läsplattans PMF är god. / This study researched digital reading habits and e-readers, from a human-computer interaction perspective, to contribute with insights regarding digital reading by identifying problems and development areas for e-readers. A survey was conducted, where 947 answers were aquired. Further, stakeholder interviews, an expert interview and user interviews were carried out for a deeper analysis. The results identified ”Purchasing process and synchronization” and ”Library management and sorting” as two critical problem areas. Formulated suggested solutions were; automatic synchronization, a simplified payment process, watermarked e-books, subscription service with a larger selection of e-books, simplified process for buying books from different suppliers, better recommendation algorithm, gameification, using the app as a starting point for synchronization to all digital devices, sorting of read / unread e-books, the ability to mark favorite e-books in the library, and a layout mode where only the book title is visible and a large number of books can be displayed. Furthermore, the e-readers Product-Market Fit (PMF) was examined, by measuring the product’s Net Promoter Score (NPS), and measuring the amount of users that would have been disappointed if the ereader disappeared and they could no longer use the product. NPS was calculated to 41, which indicate a good PMF. Furthermore, 71 % of the users stated ,in the survey, that they would be ”Very disappointed” if the e-reader disappeared, which indicate that the e-readers PMF is good.

No description available.

Nagrinėjama spausdinimo metu ant atspaudo užnešamų ultravioletinių dažų sukietinimo (užsitvirtinimo) problema. Spausdinama ritinine plokščiosios ofsetinės spaudos spausdinimo mašina. Apžvelgti eksperimentiniai ir teoriniai problemos aspektai. Aprašoma dažų džiovinimo ultravioletinėmis lempomis specifika, spausdinimo mašinos ir džiovinimo įrenginių parametrų įtaka dažų sukietinimo kokybei. Pateikiama eksperimentų planavimo metodu paremta tyrimo metodika ir jos pagrindu gauti duomenys, parodantys technologinių faktorių įtaką dažų sukietinimui. Didžiausią įtaką nagrinėjamų ultravioletinių dažų sukietinimui daro ultravioletinių lempų skaičius. / The problems of hardening (fixing) of ultraviolet ink while putting it on the imprint during the printing process are examined. The product is printed with the web-fed offset printing press. Experimental and theoretical questions are investigated. The specific features of ultraviolet ink curing using the ultraviolet radiation lamps as well as the parameters of the printing press and ultraviolet curing devices, which affect the quality of the imprint, are described. The results are presented in reference to the research methods based on the mathematical design of experiments. The results reveal how different technological factors’ affect the investigated hardening. The biggest influence on the investigated ultraviolet ink hardening has the number of ultraviolet lamps.

Microsieves are permeable membranes with excellent properties for filtration applications. In this thesis the inkjet-technology is applied (1) to manufacture micro-porous microsieves, and (2) to reinforce the mechanical stability of float-cast, nano-porous microsieves: (1) The current process for inkjet-printed microsieves includes a manual step which is substituted by inkjet printing in order to increase the level of automation. The obtained microsieves are characterized regarding the pore size distribution. Effects which occur during the manufacture and broaden the pore size distribution are identified. Based on the results, the process is improved to obtain fully inkjet-printed microsieves with a narrowed pore size distribution. (2) The mechanical stability of fragile, float-cast microsieves is improved by the application of inkjet-printed reinforcement patterns on top of the microsieves. A machine is built to combine both technologies of float-casting and inkjet printing. The printing process is improved to manufacture reinforcement patterns of well-defined geometry. / Mikrosiebe sind permeable Membranen mit herausragenden Eigenschaften für die Anwendung in der Filtration. In der vorliegenden Dissertation wird die Inkjet-Drucktechnologie angewandt, um (1) mikroporöse Mikrosiebe herzustellen und (2) nanoporöse Mikrosiebe mechanisch zu stabilisieren: (1) Die Herstellung von Mikrosieben mittels Inkjet-Druck beinhaltet momentan einen manuellen Schritt, der durch einen Inkjet-Druckschritt ersetzt wird, um den Automatisierungsgrad des Verfahrens zu erhöhen. Die Mikrosiebe werden bezüglich der Porengrößenverteilung untersucht. Auftretende Effekte, die die Porengrößenverteilung verbreitern, werden identifiziert. Aus den Resultaten dieser Analyse wird der Prozess optimiert, um Mikrosiebe mit einer engen Porengrößenverteilung herzustellen. (2) Die mechanische Stabilität von fragilen Mikrosieben, die mittels Float-Casting hergestellt werden, wird durch das Aufbringen einer Stützstruktur mittels Inkjet-Druck verstärkt. Ein Maschinensetup wird aufgebaut um beide Technologien des Float-Castings und des Inkjet-Drucks zu kombinieren. Weiterhin wird der Prozess dahingehend optimiert, Stützstrukturen mit wohl-definierten Parametern zu erzielen.

<p>U disertaciji je prikazan postupak razvoja modela praćenja procesnih parametara štampe tekstilnih materijala koji za rezultat ima kvalitetnu i postojanu štampu sa upravljivim i predvidivim procesom. U radu su date osnove praćenja procesnih parametara štampe tekstilnih materijala. Pratio se uticaj povećanja broja nanosa boje na različitim tekstilnim materijalima, i njihov uticaj na otpornost odštampanih uzoraka na svetlost, pranje, toplotno dejstvo i trljanje što je osnova razvoja modela disertacije.</p> / <p>The dissertation presents development of the process parameters monitoring model for textile printing which provides high-quality and consistent printing with controllable and predictable process parameters. The thesis provides the basis for monitoring of textile printing process parameters such as influence of number of ink layers printed on light fastness, washing fastness, scrubbing and thermal treatment various textile materials.</p>

I explore visual and process-based systems to solidify the allusive nature of conceptual ideas. Impermanence, time and interdependence are reoccurring themes that stem from an interest in Eastern philosophy. Oscillating from representation to abstract minimalism, printmaking to sculpture, each element in a work is tailored to the concept. The minimalist appearance suggests simplicity, however elaborate planning and systematic execution are at the heart of my practice. Systems create great constraint, yet provide great freedom.

The aim of this work was to develop a solid knowledge on formulation effects controlling offset ink-paper coating adhesion and to identify key factors of the coating and printing process affecting it. Focus lay on comprehending the impact of pigment dispersant on ink-paper coating adhesion and ultimately on the print quality of offset prints. The work covers laboratory studies, a pilot coating trial designed to produce coated material with a span in surface chemistry and structure, and an industrial offset printing trial. The lab scale studies quantified ink-paper coating adhesion failure during ink setting with a developed laboratory procedure based on the Ink-Surface Interaction Tester (ISIT) and image analysis. Additional polyacrylate dispersant resulted in slower ink setting and reduced ink-paper coating adhesion, with a dependence on its state of salt neutralisation and cation exchange, mainly in the presence of moisture/liquid water. The industrial printing trial on pilot coated papers was designed to study how these laboratory findings affected full scale offset print quality. These trials confirmed the dispersant-sensitive effect on ink-paper coating adhesion, especially at high water feeds. Evaluation of prints from the printing trial resulted in two fundamentally different types of ink adhesion failure being identified. The first type being traditional ink refusal, and the second type being a novel mechanism referred to as ink-lift-off adhesion failure. Ink-lift-off adhesion failure occurs when ink is initially deposited on the paper but then lifted off in a subsequent print unit. In this work, ink adhesion failure by this ink-lift-off mechanism was observed to occur more often than failure due to ink refusal. Print quality evaluation of the industrial prints suggested that water induced mottle was caused by a combination of ink-surface adhesion failure, creating white spots on the print, together with variation in ink layer thickness due to emulsified ink. / <p>QC 20161019</p>

Energia é um recurso que historicamente apresenta tendência de crescimento de demanda. Projeções indicam que, para suprir as necessidades energéticas do futuro, será necessário um uso massivo do hidrogênio como combustível. O uso de sistemas de célula a combustível baseada no uso de membrana polimérica condutora de prótons (PEMFC) tem características que permitem sua aplicação para geração de energia elétrica em aplicações estacionárias, automotivas e portáteis. O uso de hidrogênio como combustível para PEMFC apresenta a vantagem de resultar em baixa emissão de poluentes quando comparado às dos combustíveis fósseis. Para que ocorram as reações em uma PEMFC é necessária a construção de conjuntos eletrodo-membrana-eletrodo (MEA), sendo o processo de produção de MEAs e os materiais utilizados, relevantes no custo final do kW instalado para geração de energia por sistemas de célula a combustível, o que é, atualmente, uma barreira tecnológica e financeira para a aplicação em grande escala desta tecnologia. Nesse trabalho foi desenvolvido um processo de produção de MEAs por impressão a tela que apresenta alta reprodutibilidade, rapidez e baixo custo. Foram desenvolvidos o processo de impressão a tela e a composição de uma tinta precursora da camada catalisadora (TPCC), que permitem o preparo de eletrodos para confecção de MEAs com a aplicação da massa exata de eletrocatalisador adequada para cátodos 0,6 miligramas de platina por centímetro quadrados (mgPt.cm-2) e ânodos 0,4 mgPt.cm-2 em apenas uma aplicação por eletrodo. A TPCC foi desenvolvida, produzida, aplicada e caracterizada, apresentando características semelhantes a de tintas de impressão a tela para outras aplicações. Os MEAs produzidos apresentaram desempenho de até 712 mA.cm-2 a 600 mV para MEAs de 25 cm2 e o custo para produção de MEAs de 247,86 cm2 capazes de gerar 1 kW de energia foi estimado em R$ 13.939,45, considerando custo de equipamentos, materiais e mão de obra. / Energy is a resource that presents historical trend of growth in demand. Projections indicate that future energy needs will require a massive use of hydrogen as fuel. The use of systems based on the use of proton exchange membrane fuel cell (PEMFC) has features that allow its application for stationary applications, automotive and portable power generation. The use of hydrogen as fuel for PEMFC has the advantage low pollutants emission, when compared to fossil fuels. For the reactions in a PEMFC is necessary to build membrane electrode assembly (MEA). And the production of MEAs and its materials are relevant to the final cost of kW of power generated by systems of fuel cell. This represent currently a technological and financial barriers to large-scale application of this technology. In this work a process of MEAs fabrication were developed that showed high reproducibility, rapidity and low cost by sieve printing. The process of sieve printing and the ink composition as a precursor to the catalyst layer were developed, which allow the preparation of electrodes for MEAs fabrication with the implementation of the exact catalyst loading, 0.6 milligrams of platinum per square centimeters (mgPt.cm-2) suitable for cathodes and 0.4 mgPt.cm-2 for anode in only one application step per electrode. The ink was developed, produced, characterized and used with similar characteristics to ink of sieve printing build for other applications. The MEAs produced had a performance of up to 712 mA.cm-2 by 600 mV to 25 cm2 MEA area. The MEA cost production for MEAs of 247.86 cm2, that can generate 1 kilowatt of energy was estimated to US$ 7,744.14 including cost of equipment, materials and labor.