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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

Dimensioning of Punctiform Metal-Composite Joints: A Section-Force Related Failure Criterion: Dimensioning of Punctiform Metal-Composite Joints: A Section-ForceRelated Failure Criterion

Seidlitz, Holger, Ulke-Winter, Lars, Gerstenberger, Colin, Kroll, Lothar 20 April 2015 (has links)
Reliable line production processes and simulation tools play a central role for the structural integration of thermoplastic composites in advanced lightweight constructions. Provided that material- adapted joining technologies are available, they can be applied in heavy-duty multi-material designs (MMD). A load-adapted approach was implemented into the new fully automatic and faulttolerant thermo mechanical flow drill joining (FDJ) concept. With this method it is possible to manufacture reproducible high strength FRP/metal-joints within short cycle times and without use of extra joining elements for the first time. The analysis of FDJ joints requires a simplified model of the joint to enable efficient numerical simulations. The present work introduces a strategy in modeling a finite-element based analogous-approach for FDJ-joints with glass fiber reinforced polypropylene and high-strength steel. Combined with a newly developed section-force related failure criterion, it is possible to predict the fundamental failure behavior in multi-axial stress states. The functionality of the holistic approach is illustrated by a demonstrator that represents a part of a car body-in-white structure. The comparison of simulated and experimentally determined failure loads proves the applicability for several combined load cases.
32

Tuning Photovoltaic Properties of Two-dimensional Molybdenum Disulfide by Alloying: An ab initio study

Li, Mochen January 2023 (has links)
Addressing the urgent need for innovative energy solutions amidst increasing environmental concerns, the focus on photovoltaic solar cells is intensifying. Currently limited by the Shockley-Queisser limit, conventional silicon-based solar cells offer a maximum power conversion efficiency of 32%. This limitation has inspired exploration into alternative materials such as two-dimensional multi-junction heterogeneous structures, notably two-dimensional molybdenum disulfide (2D-MoS2). With a 1.86 eV bandgap and remarkable mechanical strength, 2D-MoS2 presents a potential for higher power conversion efficiency and flexibility, with an exceptional ability to accept doping atoms. This study uses the Vienna ab initio Simulation Package to predict the performance of alloyed 2D-MoS2. Transition metals are added into the structure, with specific pairs showing a promising ability to optimize the bandgap. Hybrid density functional theory methods are used to investigate the effects of alloying on the electronic structure and optical absorption. Niobium-technetium, zirconium-ruthenium, and yttrium-rhodium alloyed 2D-MoS2 show potential for greater light absorption under natural light. The bandgap is tunable between 0.51 eV and 2.13 eV through varying alloying elements and concentrations. All structures demonstrate satisfactory thermal stability. Consequently, this alloying strategy holds potential for next-generation solar cells, though experimental testing is needed. / Att adressera det brådskande behovet av innovativa energilösningar i ljuset av ökande miljöproblem, intensifieras fokus på fotovoltaiska solceller. För närvarande begränsade av Shockley-Queisser gränsen, erbjuder konventionella kiselbaserade solceller en maximal omvandlingseffektivitet på 32%. Denna begränsning har inspirerat till utforskning av alternativa material som tvådimensionella flerleds-heterogena strukturer, framför allt 2D-MoS2. Med ett bandgap på 1.86 eV och märkbar mekanisk styrka, presenterar 2D-MoS2 en potential för högre omvandlingseffektivitet och flexibilitet, med en exceptionell förmåga att acceptera dopningsatomer. Denna studie använder Vienna ab initio Simulation Package för att förutsäga prestanda hos legerad 2D-MoS2. Övergångsmetaller läggs till i strukturen, med specifika par som visar en lovande förmåga att optimera bandgapet. Hybrid densitetsfunktionell teori metoder används för att undersöka effekterna av legering på den elektroniska strukturen och optiska absorptionen. Niobium-teknecium, zirkonium-ruthenium och yttrium-rhodium legerade 2D-MoS2 visar potential för större ljusabsorption under naturligt ljus. Bandgapet kan justeras mellan 0.51 eV och 2.13 eV genom att variera legeringselement och koncentration. Alla strukturer demonstrerar tillfredsställande termisk stabilitet. Följaktligen håller denna legeringsstrategi potential för nästa generations solceller, även om experimentell testning behövs.
33

Beitrag zum Thema VERBUNDWERKSTOFFE - WERKSTOFFVERBUNDE / Contribution on the topic COMPOSITE MATERIALS - MATERIAL COMPOUNDS : Status quo and research approaches

Nestler, Daisy Julia 15 April 2014 (has links) (PDF)
Vielschichtige Eigenschaftsprofile benötigen zunehmend moderne Verbundwerkstoffe und Werkstoffverbunde einschließlich der raschen Entfaltung neuer Fertigungstechnologien, da der monolithische Werkstoff bzw. ein einziger Werkstoff den heutigen komplexen Anforderungen nicht mehr genügen kann. Zukünftige Werkstoffsysteme haben wirtschaftlich eine Schlüsselposition und sind auf den Wachstumsmärkten von grundlegender Bedeutung. Gefragt sind maßgeschneiderte Leichtbauwerkstoffe (tailor-made composites) mit einem adaptierten Design. Dazu müssen Konzepte entwickelt werden, um die Kombination der Komponenten optimal zu gestalten. Das erfordert werkstoffspezifisches Wissen und Korrelationsvermögen sowie die Gestaltung komplexer Technologien, auch unter dem Aspekt der kontinuierlichen Massen- und Großserienfertigung (in-line, in-situ) und damit der Kostenreduzierung bislang teurer Verbundwerkstoffe und Werkstoffverbunde. In der vorliegenden Arbeit wird in vergleichbarer und vergleichender Art und Weise sowie abstrahierter Form ein Bogen über das Gesamtgebiet der Verbundwerkstoffe und Werkstoffverbunde gespannt. Eine zusammenfassende Publikation über dieses noch sehr junge, aber bereits breit aufgestellte Wissenschaftsgebiet fehlt bislang. Das ist der Separierung der einzelnen, fest aufgeteilten Gruppierungen der Verbundwerkstoffe geschuldet. Querverbindungen werden selten hergestellt. Dieses Defizit in einem gewissen Maße auszugleichen, ist Ziel der Arbeit. Besondere Berücksichtigung finden Begriffsbestimmungen und Klassifikationen, Herstellungsverfahren und Eigenschaften der Werkstoffe. Es werden klare Strukturierungen und Übersichten herausgearbeitet. Zuordnungen von etablierten und neuen Technologien sollen zur Begriffsstabilität der Terminologien „Mischbauweise“ und „Hybrider Verbund“ beitragen. Zudem wird die Problematik „Recycling und Recyclingtechnologien“ diskutiert. Zusammenfassend werden Handlungsfelder zukünftiger Forschungs- und Entwicklungsprojekte spezifiziert. Aus dem Blickwinkel der verschiedenen Herstellungsrouten insbesondere für Halbzeuge und Bauteile und der dabei gewonnenen Erkenntnisse werden verallgemeinerte Konzepte für tailor-made Verbundwerkstoffe und Werkstoffverbunde vorgeschlagen („Stellschraubenschema“). Diese allgemeinen Werkstoffkonzepte werden auf eigene aktuelle Forschungsprojekte der Schwerpunktthemen Metallmatrix- und Polymermatrix-Verbundwerkstoffe sowie der hybriden Werkstoffverbunde appliziert. Forschungsfelder für zukünftige Projekte werden abgeleitet. Besonderes Augenmerk gilt den hybriden Verbunden als tragende Säule zukünftiger Entwicklungen im Leichtbau. Hier spielen in-line- und in-situ-Prozesse eine entscheidende Rolle für eine großseriennahe, kosteneffiziente und ressourcenschonende Produktion. / Complex property profiles require increasingly advanced composite materials and material compounds, including the rapid deployment of new production technologies, because the monolithic material or a single material can no longer satisfy today's complex requirements. Future material systems are fundamentally important to growth markets, in which they have an economically key position. Tailor-made lightweight materials (tailor-made composites) with an adapted design are needed. These concepts have to be developed to design the optimum combination of components. This requires material-specific knowledge and the ability to make correlations, as well as the design of complex technologies. Continuous large-scale and mass production (in-line, in-situ), thus reducing the costs of previously expensive composite materials and material compounds, is also necessary. The present work spans the entire field of composite materials and material compounds in a comparable and comparative manner and abstract form. A summarizing publication on this still very new, but already broad-based scientific field is not yet available. The separation of the individual, firmly divided groups of the composite materials is the reason for this. Cross-connections are rarely made. The objective of this work is to compensate to some extent for this deficiency. Special consideration is given to definitions and classifications, manufacturing processes and the properties of the materials. Clear structures and overviews are presented. Mapping established and new technologies will contribute to the stability of the terms "mixed material compounds" and "hybrid material compounds". In addition, the problem of recycling and recycling technologies is discussed. In summary, areas for future research and development projects will be specified. Generalized concepts for tailor-made composite materials and material compounds are proposed ("adjusting screw scheme") with an eye toward various production routes, especially for semi-finished products and components, and the associated findings. These general material concepts are applied to own current research projects pertaining to metal-matrix and polymer-matrix composites and hybrid material compounds. Research fields for future projects are extrapolated. Particular attention is paid to hybrid material compounds as the mainstay of future developments in lightweight construction. In-line and in-situ processes play a key role for large-scale, cost- and resource-efficient production.
34

Varför är det en hamburgare i det högra hörnet? : En analys av CSS ramverk / Why is there a hamburger in the right hand corner?

Carlsson, Emil, Andersson Waara, Daniela January 2017 (has links)
Purpose – The purpose of this report is to find out which frameworks and methods are most popular and most widely used, as well as web developers' views on the hamburgermenu. Method – In order to answer the questions in our report we used the methods quantitative statistical processing, quantitative analysis of data collected via survey and qualitative interviews with web developers. The study was conducted to find out which frameworks and methods are most popular and used most, as well as how web developers look at the hamburgermenu. This was done by analyzing the popularity and usage of different frameworks as well as interviewing web developers who work with it daily. Findings – The results of the report are based on the data collected through the processing of the statistics, the analysis of the survey, and the interviews performed. The result shows which frameworks are most popular and those that are most used. The following list shows the ranking: Most popular: Bootstrap Semantic UI Materialize Material Design Lite Foundation Most used: Bootstrap Foundation Materialize Material Design Lite Semantic UI The results of the interviews showed that most of the web developers interviewed used a framework when they created a website, either an existing or one of their own. It was also a practice to use the same framework in the company, although the way it was used was different from developer to developer. All developers had a mobile-first thought in mind, although it was not always a priority. It was also found in the study that everyone had a basic idea behind the choice of framework, but only one who had performed a study on which one would suit them best. All web developers interviewed thought that the hamburger menu was boring and bad from a user experience perspective. But everyone also agreed that because it is so widely used and has been for a couple of years, users have learned what it means and therefore fulfills its purpose. Implications – The use of the results is primarily linked to individuals or companies that work with web development, but can also be used by private individuals. For the report's primary target group, the results will give an increased understanding of the most used framework and an increased understanding of why these are used. Private individuals can use the result in the same way. Limitations – The limitations we receive in this study are that we cannot make any conclusions about companies and web developers in other parts of the country using the same framework or methods as the local ones we interviewed. Nor can we make any conclusions about why Bootstrap is the most popular and most widely used framework. We can only speculate why with the empirical we gathered through the interviews. A major limitation is also the lack of interviews when we only got answers from 6 of the 10 companies we contacted, of whom 4 would like to participate in the interview. More general conclusions could have been drawn if more companies had been interviewed. Keywords – Framework, Web Development, Responsive Web Design, Interaction Design, User Experience, Bootstrap, Foundation, Materialize, Material Design Lite, Semantic UI / Syfte – Syftet med denna rapport är att ta reda på vilka ramverk och metoder som är populärast och mest använda, samt webbutvecklares syn på hamburgermenyn. Metod – För att besvara frågeställningarna används metoderna kvantitativ bearbetning av statistik, kvantitativ analys av data insamlad via survey samt kvalitativa intervjuer med webbutvecklare. Studien genomfördes för att ta reda på vilka ramverk och metoder som är populärast och används mest, samt hur webbutvecklare ser på hamburgermenyn. Detta gjordes genom att analysera olika ramverks popularitet och användande samt att intervjua webbutvecklare som arbetar med det dagligen. Resultat – Rapportens resultat är baserat på den data som samlats in genom bearbetningen av statistiken, analysen av survey, samt de intervjuer som utfördes. Resultatet visar vilka ramverk som är populärast samt vilka som används mest. Följande lista visar rangordningen: Populärast: Bootstrap Semantic UI Materialize Material Design Lite Foundation Mest använt: Bootstrap Foundation Materialize Material Design Lite Semantic UI Resultatet av intervjuerna visade att majoriteten av de webbutvecklare som intervjuades använde ett ramverk när de skapade en hemsida, antingen ett existerande eller ett eget skapat. Det var också praxis att använda samma ramverk i företaget, även om sättet man arbetade med det kunde skilja sig från utvecklare till utvecklare. Samtliga utvecklare hade ett mobile-first tänk i åtanke, även om det inte alltid prioriterades. Det framgick även i studien att samtliga hade en grundtanke bakom valet av ramverk, men det var endast en som faktiskt hade utfört en undersökning om vilket som skulle passa dem bäst. Samtliga webbutvecklare som intervjuades tyckte att hamburgermenyn var tråkig och dålig ur ett användarupplevelseperspektiv. Men samtliga tyckte även att eftersom den används så brett och har gjort i ett par år så har användare lärt sig vad den innebär och fyller därför sitt syfte. Implikationer – Resultatets användningsområden är främst kopplade till personer eller företag som arbetar med webbutveckling men kommer även att kunna användas av privatpersoner. För rapportens primära målgrupp kommer resultatet att ge en ökad förståelse för vilka ramverk som används mest samt en ökad förståelse för varför dessa används. Privatpersoner kan använda resultatet på samma sätt. Begränsningar – Begränsningarna som vi får i denna studie är att vi inte kan dra några slutsatser om företag och webbutvecklare i andra delar av landet använder sig av samma ramverk eller metoder som de lokala vi intervjuat. Vi kan heller inte dra några slutsatser om varför Bootstrap är det mest populära och mest använda ramverket. Vi kan endast spekulera om varför med hjälp av den empiri vi samlat in via intervjuerna. En stor begränsning är även bristen av intervjuer då vi endast fick kontakt med 6 av de 10 företag som vi kontaktade, varav 4 stycken ville ställa upp på att delta i intervju. Fler generella slutsatser hade kunnat dras om fler företag hade ställt upp på intervjuer. Nyckelord – Ramverk, Webbutveckling, Responsiv webbdesign, Interaktionsdesign, Användarupplevelse, Bootstrap, Foundation, Materialize, Material Design Lite, Semantic UI
35

Beitrag zum Thema VERBUNDWERKSTOFFE - WERKSTOFFVERBUNDE: Status quo und Forschungsansätze

Nestler, Daisy Julia 04 November 2013 (has links)
Vielschichtige Eigenschaftsprofile benötigen zunehmend moderne Verbundwerkstoffe und Werkstoffverbunde einschließlich der raschen Entfaltung neuer Fertigungstechnologien, da der monolithische Werkstoff bzw. ein einziger Werkstoff den heutigen komplexen Anforderungen nicht mehr genügen kann. Zukünftige Werkstoffsysteme haben wirtschaftlich eine Schlüsselposition und sind auf den Wachstumsmärkten von grundlegender Bedeutung. Gefragt sind maßgeschneiderte Leichtbauwerkstoffe (tailor-made composites) mit einem adaptierten Design. Dazu müssen Konzepte entwickelt werden, um die Kombination der Komponenten optimal zu gestalten. Das erfordert werkstoffspezifisches Wissen und Korrelationsvermögen sowie die Gestaltung komplexer Technologien, auch unter dem Aspekt der kontinuierlichen Massen- und Großserienfertigung (in-line, in-situ) und damit der Kostenreduzierung bislang teurer Verbundwerkstoffe und Werkstoffverbunde. In der vorliegenden Arbeit wird in vergleichbarer und vergleichender Art und Weise sowie abstrahierter Form ein Bogen über das Gesamtgebiet der Verbundwerkstoffe und Werkstoffverbunde gespannt. Eine zusammenfassende Publikation über dieses noch sehr junge, aber bereits breit aufgestellte Wissenschaftsgebiet fehlt bislang. Das ist der Separierung der einzelnen, fest aufgeteilten Gruppierungen der Verbundwerkstoffe geschuldet. Querverbindungen werden selten hergestellt. Dieses Defizit in einem gewissen Maße auszugleichen, ist Ziel der Arbeit. Besondere Berücksichtigung finden Begriffsbestimmungen und Klassifikationen, Herstellungsverfahren und Eigenschaften der Werkstoffe. Es werden klare Strukturierungen und Übersichten herausgearbeitet. Zuordnungen von etablierten und neuen Technologien sollen zur Begriffsstabilität der Terminologien „Mischbauweise“ und „Hybrider Verbund“ beitragen. Zudem wird die Problematik „Recycling und Recyclingtechnologien“ diskutiert. Zusammenfassend werden Handlungsfelder zukünftiger Forschungs- und Entwicklungsprojekte spezifiziert. Aus dem Blickwinkel der verschiedenen Herstellungsrouten insbesondere für Halbzeuge und Bauteile und der dabei gewonnenen Erkenntnisse werden verallgemeinerte Konzepte für tailor-made Verbundwerkstoffe und Werkstoffverbunde vorgeschlagen („Stellschraubenschema“). Diese allgemeinen Werkstoffkonzepte werden auf eigene aktuelle Forschungsprojekte der Schwerpunktthemen Metallmatrix- und Polymermatrix-Verbundwerkstoffe sowie der hybriden Werkstoffverbunde appliziert. Forschungsfelder für zukünftige Projekte werden abgeleitet. Besonderes Augenmerk gilt den hybriden Verbunden als tragende Säule zukünftiger Entwicklungen im Leichtbau. Hier spielen in-line- und in-situ-Prozesse eine entscheidende Rolle für eine großseriennahe, kosteneffiziente und ressourcenschonende Produktion. / Complex property profiles require increasingly advanced composite materials and material compounds, including the rapid deployment of new production technologies, because the monolithic material or a single material can no longer satisfy today's complex requirements. Future material systems are fundamentally important to growth markets, in which they have an economically key position. Tailor-made lightweight materials (tailor-made composites) with an adapted design are needed. These concepts have to be developed to design the optimum combination of components. This requires material-specific knowledge and the ability to make correlations, as well as the design of complex technologies. Continuous large-scale and mass production (in-line, in-situ), thus reducing the costs of previously expensive composite materials and material compounds, is also necessary. The present work spans the entire field of composite materials and material compounds in a comparable and comparative manner and abstract form. A summarizing publication on this still very new, but already broad-based scientific field is not yet available. The separation of the individual, firmly divided groups of the composite materials is the reason for this. Cross-connections are rarely made. The objective of this work is to compensate to some extent for this deficiency. Special consideration is given to definitions and classifications, manufacturing processes and the properties of the materials. Clear structures and overviews are presented. Mapping established and new technologies will contribute to the stability of the terms "mixed material compounds" and "hybrid material compounds". In addition, the problem of recycling and recycling technologies is discussed. In summary, areas for future research and development projects will be specified. Generalized concepts for tailor-made composite materials and material compounds are proposed ("adjusting screw scheme") with an eye toward various production routes, especially for semi-finished products and components, and the associated findings. These general material concepts are applied to own current research projects pertaining to metal-matrix and polymer-matrix composites and hybrid material compounds. Research fields for future projects are extrapolated. Particular attention is paid to hybrid material compounds as the mainstay of future developments in lightweight construction. In-line and in-situ processes play a key role for large-scale, cost- and resource-efficient production.
36

Template directed synthesis of porphyrin nanorings

O'Sullivan, Melanie Claire January 2011 (has links)
This thesis describes supramolecular approaches to porphyrin nanorings. Cyclic porphyrin arrays resemble natural light harvesting systems, and it is of interest to probe the photophysical effects of bending the porphyrin aromatic π-system. A general overview of the synthesis and photophysical properties of porphyrins and their arrays is carried out in Chapter 1. The electronic structure of porphyrins is examined, and how conformational effects in oligomers, such as inter-porphyrin torsional angle and backbone bending influence the π-conjugation pathway. The structures of light harvesting complexes are discussed. Chapter 2 describes the design and synthesis of a complementary 12-armed template designed to coordinate linear porphyrin oligomers in the correct conformation for cyclisation to give a cyclic porphyrin dodecamer. Chapter 3 demonstrates two approaches to a cyclic porphyrin dodecamer ring. Firstly, a classical templating approach using the 12-armed template is described. The limitations of this approach in the quest for larger nanorings are discussed. Vernier templating, which utilises a mismatch in the number of binding sites between a ligand and its receptor is introduced as a general strategy to the synthesis of large nanorings. This is demonstrated by the synthesis of cyclic dodecamer from a linear porphyrin tetramer and a hexadentate template via a figure-of-eight intermediate. The general utility of the Vernier method to large nanorings is explored in Chapter 4 with steps towards the synthesis of a cyclic tetracosamer, consisting of 24 porphyrin subunits. In preliminary experiments, an improved route to the cyclic porphyrin octamer is described. Finally, the photophysical properties of the nanoring series are explored in Chapter 5 as a function of size and conformation. Femtosecond photoluminescence spectroscopy shows that even in cyclic dodecamer, exciton delocalisation over the entire porphyrin backbone occurs on a sub-picosecond timescale, and parallels are drawn with the dynamics of natural light harvesting complexes.
37

Functional and inhibition studies on 2-oxoglutarate-dependent oxygenases

Thalhammer, Armin January 2012 (has links)
This thesis explores roles of 2-oxoglutarate-dependent (2OG) oxygenases as interfaces that modulate steps in the flow of genetic information in cells in response to oxygen availability. Chapter 1 introduces mechanistic, biochemical and physiological aspects of major subfamilies of 2OG oxygenases, and their established regulatory roles in cells. In addition, structural and functional aspects of the ribosome and the translation process are discussed, with a focus on post-translational ribosome modifications. Chapter 2 investigates histone demethylases, which mediate chromatin-dependent regulation of gene expression and provides proof-of-concept for the rational, structure-guided design of small-molecules for selective inhibition of 2OG oxygenases with roles in cancer and inflammatory disease. Chapter 3 suggests regulatory roles for ten-eleven-translocation (TET)- catalysed DNA hydroxylation; calorimetric and thermal analyses reveal a duplex-stabilizing effect of the epigenetic 5-methylcytosine mark that is reversed upon conversion to 5- hydroxymethylcytosine (also termed the ‘sixth’ DNA base), raising the possibility that 2OG oxygenase catalysis might affect transcription via biophysical effects. Chapter 4 investigates fluoride release assays as a technology to enable medicinal chemistry studies on 2OG oxygenases with roles in fat mass regulation and obesity, cancer and inflammation; studies on the ALKBH5 enzyme show that it is a hypoxically upregulated 2OG oxygenase with a substrate preference distinct from previously characterized ALKBH enzymes. Chapter 5 identifies OGFOD1 as a 2OG-dependent ribosomal protein hydroxylase. OGFOD1 catalysis is conserved from yeast to humans. OGFOD1 catalyses formation of trans-3- hydroxy-L-proline in a highly conserved loop of ribosomal protein S23 proximal to the ribosomal decoding centre, possibly to modulate the interactions of eukaryotic ribosomes with tRNA, mRNA and translation factors in an oxygen-dependent manner. OGFOD1 is the functionally most well-conserved protein-modifying 2OG oxygenase; likewise, ribosomal protein S23 hydroxylation is the most well-conserved post-translational ribosome modification in eukaryotes. Some cell lines require OGFOD1 for proliferation, and scaffolds for OGFOD1- selective inhibitors are developed for use as potential antiproliferative agents and probes for cellular function. Chapter 6 shows the development of assays to investigate whether OGFOD1 catalysis affects ribosome assembly and function, including processivity, accuracy of initiation, elongation and termination, in yeast and mammalian cell lines. Chapter 7 concludes that ribosome hydroxylation might present an additional layer of regulatory complexity by which 2OG oxygenases could enable cells to respond to fluctuating oxygen levels.
38

Konstrukce brzdičky příze s mechanickým přidržováním stroje Air-Jet / Construction of yarn keeper with mechanic clamp of Air-Jet machine

Jíša, Martin January 2016 (has links)
This diploma thesis describes methods of textile fibers treatment, production levels with detailed focus on spinning process especially by Rieter AG in Winterthur, Switzerland, subsidiary company in Usti nad Orlici. Thesis also describes production materials and it’s behavior in relations to production machines. Analysis of the current solution, it’s pros and cons is also done. Setting of requirements of new solution. Creating proposals of design solutions of yarn keeper with mechanic clamp situated on spinning unit on Air-Jet machine. Creating concepts and proposal schemes. After choosing of best possible solution considering production costs, electric consumption during working machine and during active cycle was this variation produce. At the end is review of complete solution and prospective next steps in testing not only in laboratory and prospects of using in field.
39

Potential and application fields of lightweight hydraulic components in multi-material design

Ulbricht, Andreas, Gude, Maik, Barfuß, Daniel, Birke, Michael, Schwaar, Andree, Czulak, Andrzej January 2016 (has links)
Hydraulic systems are used in many fields of applications for different functions like energy storage in hybrid systems. Generally the mass of hydraulic systems plays a key role especially for mobile hydraulics (construction machines, trucks, cars) and hydraulic aircraft systems. The main product properties like energy efficiency or payload can be improved by reducing the mass. In this connection carbon fiber reinforced plastics (CFRP) with their superior specific strength and stiffness open up new chances to acquire new lightweight potentials compared to metallic components. However, complex quality control and failure identification slow down the substitution of metals by fiber-reinforced plastics (FRP). But the lower manufacturing temperatures of FRP compared to metals allow the integration of sensors within FRP-components. These sensors then can be advantageously used for many functions like quality control during the manufacturing process or structural health monitoring (SHM) for failure detection during their life cycle. Thus, lightweight hydraulic components made of composite materials as well as sensor integration in composite components are a main fields of research and development at the Institute of Lightweight Engineering and Polymer Technology (ILK) of the TU Dresden as well as at the Leichtbau-Zentrum Sachsen GmbH (LZS).
40

ODPOVĚDNÝ DESIGN / (MATERIAL) – CONSCIOUS DESIGN

Filípková, Valentýna Unknown Date (has links)
The online platform consciousdesign.cz, created as the output of the thesis, provides sources for possible conscious approaches to design. It consists of a database of innovative materials, research texts, related links and interviews with designers, material specialists, scientists and technologists. The website can serve as a starting point for students and designers who are interested in current possibilities and new ways leading to design that is responsible to nature and humans.

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