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The development of energy storage devices has represented a significant technological challenge for the past few years. Electrochemical double-layer capacitors (EDLCs), also named as supercapacitors, are a likely competitor for alternative energy storage because of their low-cost, high power density, and high fast charge/discharge rate. The recent development of EDLCs requires them to be lightweight and flexible. There are many fabrication techniques used to manufacture flexible EDLCs, and these methods can include pre-treatment to ensure more efficient penetration of activated carbon (AC) patterns onto the substrate, or those that utilise masks for the definitions of patterns on substrates. However, these methods are inconvenient for building cost-effective devices. Therefore, it was necessary to find a suitable process to reduce the steps of manufacture and to be able to print multiple materials uniformly. This research work describes the first use of a 3D printing technology to produce flexible EDLCs for energy storage. In this research work, the four essential elements for the EDLCs substrate, current collector, activated electrode, and gel electrolyte were investigated. The AC powder was milled by ball milling to optimise the paste deposition and the electrochemical performance. A flexible composite EDLC was designed and manufactured by 3D printing. The electrochemical performance of the flexible composite EDLCs was then examined. Being highly flexible is one of the critical demands for the recent development of EDLCs. Therefore, highly flexible EDLCs were designed and manufactured by only one single extrusion process. The 3D highly flexible EDLC maintains significant electrochemical performance under a mechanical bending test. To meet the power and energy requirements, the EDLCs were connected and tested in series and parallel circuits. A supercapacitor based on printed AC material displays an area specific capacitance of 1.48 F/cm2 at the scan rate of 20 mV/s. The coulombic efficiency for the flexible EDLC was found to be 59.91%, and the cycling stability was achieved to be 56% after 500 cycles. These findings indicate that 3D printing technology may be increasingly used to develop more sophisticated flexible wearable electronic devices.

Topic of the thesis is the production of unipolar digital circuits by means of mass-printing technologies. For this purpose accumulation-mode and depletion-mode field-effect transistors have been used. To realize depletion-mode field-effect transistors charges are injected and stored in the gate-dielectric. Consequently, the charge transport on the semiconductor-dielectric interface is influenced and the threshold voltage can be controlled. To inject charges into the dielectric different technologies have been used and will be discussed in terms of their process parameters. Finally, fully-printed digital circuits with enhanced performance are introduced. / Gegenstand der vorliegenden Arbeit ist die drucktechnische Herstellung von unipolaren digitalen Schaltungen durch eine Kombination von organischen Feldeekttransistoren vom Anreicherungs- und Verarmungstyp. Zur Realisierung von Transistoren vom Verarmungstyp werden Überschussladung in den Gate- Isolator eingebracht und gespeichert, wodurch der Ladungstransport im Transistorkanal insbesondere die Schwellspannung beeinflusst wird. Es werden verschiedene Aufladungstechnologien und deren Prozessparameter diskutiert. Abschließend werden vollständig mit Massendruckverfahren prozessierte, digitale Schaltungen mit verbesserter Signalübertragungscharakteristik vorgestellt.

Submitted by LEONARDO DE CONTI DIAS AGUIAR null (leonardodeconti@feb.unesp.br) on 2016-04-09T17:29:03Z No. of bitstreams: 1 Um processo para utilizar a tecnologia de impressão 3D na construção de instrumentos didáticos para o ensino de ciências.pdf: 8779312 bytes, checksum: c2f9f1bb85c39f2ff84434217d4f73fe (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-04-12T14:30:16Z (GMT) No. of bitstreams: 1 aguiar_ldcd_me_bauru.pdf: 8779312 bytes, checksum: c2f9f1bb85c39f2ff84434217d4f73fe (MD5) / Made available in DSpace on 2016-04-12T14:30:16Z (GMT). No. of bitstreams: 1 aguiar_ldcd_me_bauru.pdf: 8779312 bytes, checksum: c2f9f1bb85c39f2ff84434217d4f73fe (MD5) Previous issue date: 2016-02-23 / Esta dissertação trata de uma pesquisa empírica sobre a utilização da tecnologia de impressão 3D na construção de instrumentos didáticos para o Ensino de Ciências. A crescente disponibilidade da tecnologia de impressão 3D abriu oportunidades de explorações em novas áreas, como a educação. Considerando as oportunidades de uso dessa tecnologia para a criação de materiais didáticos, este trabalho mostra como tal tecnologia pode ser utilizada por professores em formação e professores em serviço. Desta forma, um processo prático foi proposto e avaliado por meio de uma oficina. O processo consiste em 6 etapas distintas: identificação das necessidades de ensino por meio da seleção de conteúdos e conceitos científicos; desenvolvimento do plano de construção do instrumento didático desejado; elaboração de rascunhos considerando as dimensões físicas do objeto a ser construído; modelagem 3D do objeto utilizando softwares de desenho ou buscando por modelos prontos; preparação e impressão do modelo 3D na impressora 3D; utilização e avaliação do objeto real gerado. Esse processo foi apresentado e ensinado para alunos de licenciatura construírem instrumentos didáticos em uma oficina. A análise dos dados coletados nessa oficina por meio de observações, entrevistas e questionários mostram que: o processo pode guiar sobre quais são os passos a serem percorridos para construir instrumentos didáticos utilizando impressoras 3D; ocorrem situações estimuladoras ao aprendizado durante as construções; o uso desta tecnologia pode colaborar com o desenvolvimento da instrumentação para o Ensino de Ciências. Concluiu-se que, para se realizar o uso dessa tecnologia, é preciso que o professor desenvolva novas habilidades, como: planejar a construção de objetos levando em conta restrições técnicas das impressoras 3D, aprender a desenhar em softwares de modelagem 3D, preparar o modelo 3D para que a impressora 3D o construa (etapa denominada fatiamento) e a utilizar recursos informacionais para compartilhar e reutilizar modelos 3D de instrumentos didáticos criado por outras pessoas. Essa pesquisa contribui com o Ensino de Ciências, uma vez que: fornece uma forma sistemática para utilização da tecnologia de impressão 3D na educação; acrescenta novo conhecimento sobre o tema em uma área onde a literatura é escassa; abre oportunidades para que o conhecimento gerado por meio dos instrumentos didáticos construídos utilizando o processo proposto possa ser compartilhado com outros professores. / This thesis is an empirical research on the use of 3D printing technology in the construction of didactic tools for science teaching. The growing availability of 3D printing technology has opened exploration opportunities in new areas such as education. Considering the opportunities of this technology for the creation of teaching materials, this study shows how such technology can be used in the teacher education and by teachers in service. So, a practical process was proposed and evaluated by its use in a workshop. The process consists in 6 distinct stages: identification of educational needs through the selection of scientific content and concepts; development of the construction plan of the desired teaching tool; preparation of drafts considering the physical dimensions of the object to be built; 3D modeling of the object using drawing software or searching for 3D models created by others; preparation and printing of the 3D model in the 3D printer; use and evaluation of the real object generated. This process was presented and taught for undergraduate students for them build didactic tools during a practical workshop. The analysis of the collected data in this workshop through observations, interviews and questionnaires show that: the process can guide on which are the steps to be taken to build teaching tools using 3D printers; during the constructions occurs situations that stimulate the learning; the use of this technology can contribute to the development of instrumentation for Science Teaching. It was concluded that to do the use of this technology, it is required that the teacher develop new skills, such as planning the construction of objects taking into account technical constraints of 3D printers, learn to draw in 3D modeling software, prepare the 3D model to the 3D printer build it (step called slicing) and use IT resources to share and reuse 3D models of didactic tools created by others. This research contributes to the Teaching of Science, because: it provides a systematic way to use 3D printing technology in education; adds new knowledge on the subject in an area where the literature is scarce; It opens opportunities for knowledge generated through the teaching tools built using the proposed process can be shared with other teachers.

Subject of dissertation was to itemize testing methods in fresh and hardened state of cement paste or concrete. During this process some new testing methods and specimen creation protocols were proposed. Further was created list of used materials and mix design processes which led to list of used 3D printing mixture designs and 3D printers. Next part of dissertation was devoted to creation of 3D printing mix design and observations based on them. At~the end is proposed a radical change in testing methods which utilizes latest advancements in computer science and could be part of digital design process for construction.

We report on the detailed electrical investigation of all-inkjet-printed thin-film transistor (TFT) arrays focusing on TFT failures and their origins. The TFT arrays were manufactured on flexible polymer substrates in ambient condition without the need for cleanroom environment or inert atmosphere and at a maximum temperature of 150 °C. Alternative manufacturing processes for electronic devices such as inkjet printing suffer from lower accuracy compared to traditional microelectronic manufacturing methods. Furthermore, usually printing methods do not allow the manufacturing of electronic devices with high yield (high number of functional devices). In general, the manufacturing yield is much lower compared to the established conventional manufacturing methods based on lithography. Thus, the focus of this contribution is set on a comprehensive analysis of defective TFTs printed by inkjet technology. Based on root cause analysis, we present the defects by developing failure categories and discuss the reasons for the defects. This procedure identifies failure origins and allows the optimization of the manufacturing resulting finally to a yield improvement.

Gegenstand der vorliegenden Arbeit ist die ortsaufgelöste Untersuchung der Schichtdicke und der elektrischen Eigenschaften von Funktionsschichten in gedruckten Polymersolarzellen. Die massendrucktechnische Realisierung der großflächigen Polymersolarzellen mit dem Schichtaufbau Zink/ZnO/P3HT:PCBM/PEDOT:PSS erfolgt im Tief- und Siebdruckverfahren auf einem papierbasierten Bedruckstoff. Die gedruckten Funktionsschichten werden mit verschieden optischen und elektrischen Messverfahren charakterisiert und die Eignung der Verfahren wird diskutiert. Abschließend wird die gesamte Polymersolarzelle mit einer Kombination aus spektraler und elektrischer Messung positionsgenau untersucht. Dadurch kann ein Zusammenhang zwischen den Solarzelleneigenschaften und den ortsaufgelösten Messwerten aufgezeigt werden. / The aim of this work is the space-resolved investigation of the layer thickness and the electrical properties of functional layers in printed polymer solar cells. The realization of the large-area polymer solar cells with a layer structure of zinc/ZnO/P3HT:PCBM/PEDOT:PSS occurs by gravure and screen printing on a paper-based substrate. The printed functional layers are characterized by different optical and electrical measurement methods and the suitability of these methods is discussed. Finally, the complete polymer solar cell is examined dependent on a position by using a combination of spectral and electrical measurement techniques. With this analysis a correlation between the solar cell characteristics and the space-resolved measurements can be shown.

The following report consists of a master thesis (30 credits) within product development. The thesis is written by Philip Ragnartz and Axel Staffanson, both studying mechanical engineering at Mälardalens University. Developing new components for a production line is costly and time consuming as they must be made from manual measurements and must go through all the conventional manufacturing (CM) steps. Eventual design mistakes will be discovered after the component have been manufactured and tested. To fix the design a completely new component must be designed and therefore double the overall lead time. The purpose of this thesis is to establish how additive manufacturing (AM) can best be used to minimize the cost and lead time in the development of new components. The study was performed by looking at the current product development process in the automotive industry at a large company, here by referred to as company A. 56 components already manufactured at company A´s own tools department was examined and compared to different AM methods. The aim of this was to get a larger pool of data to get an average on production time and cost and see how this differ to the different AM methods. Additionally, two work holders were more closely examined in a case study. Work holder one is a component in the production line that occasionally must be remanufactured. It was examined if this problem could be solved with a desktop plastic printer to hold up for a production batch. Work holder two was the development of a new component, this was to examine the use of printing the component in an early stage impact the development process. The findings from this study is that AM can today not be used in a cost efficient way in manufacturing or development of simple components. This is due to the cost of a metal 3D-printer is still very high, and the building material even higher. This results in components that gets very expensive to make compared to producing them with CM. For design evaluation to be cost efficient there will have to be a design fault in over 12 % of the newly design components for it to be cost effective to print the design for validation before sending it to be manufactured. There are however a lot bigger potential savings in the lead time. Producing the end product with a metal 3D-printer can cut down the lead time up to 85 %. This is thanks to the fact that the printer will produce the component all in one step and therefore not get stuck in between different manufacturing processes. The same goes for design evaluation with printing the component in plastic to confirm the design and not risk having to wait for the component to be manufactured twice. Despite the facts that it is not cost efficient to use AM there are other factors that play an important role. To know that the designed components will work will create a certainty and allow the development process to continue. In some cases it will also allow the designer to improve the design to function better even if the first design would have worked. As AM is expanding machines and build materials will become cheaper. Eventually it will become cheaper to 3D-print even simple components compared to CM. When this occurs, a company cannot simply buy a 3D-printer and make it profitable. There is a learning curve with AM that will take time for the designers to adapt to. Therefore, it is good to start implementing it as soon as possible as it allows for more intricate designs and require experience to do so.

Topic of the thesis is the production of unipolar digital circuits by means of mass-printing technologies. For this purpose accumulation-mode and depletion-mode field-effect transistors have been used. To realize depletion-mode field-effect transistors charges are injected and stored in the gate-dielectric. Consequently, the charge transport on the semiconductor-dielectric interface is influenced and the threshold voltage can be controlled. To inject charges into the dielectric different technologies have been used and will be discussed in terms of their process parameters. Finally, fully-printed digital circuits with enhanced performance are introduced. / Gegenstand der vorliegenden Arbeit ist die drucktechnische Herstellung von unipolaren digitalen Schaltungen durch eine Kombination von organischen Feldeekttransistoren vom Anreicherungs- und Verarmungstyp. Zur Realisierung von Transistoren vom Verarmungstyp werden Überschussladung in den Gate- Isolator eingebracht und gespeichert, wodurch der Ladungstransport im Transistorkanal insbesondere die Schwellspannung beeinflusst wird. Es werden verschiedene Aufladungstechnologien und deren Prozessparameter diskutiert. Abschließend werden vollständig mit Massendruckverfahren prozessierte, digitale Schaltungen mit verbesserter Signalübertragungscharakteristik vorgestellt.