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1
Janetzko, Steffen, Thomas Gries, and Till Büttner. "Preforming von textilen Bewehrungsstrukturen für Sandwichbauteile." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1244042345137-27083.
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Dimensionierung und Konstruktion von Bewehrungstextilien für die Anwendung in Textilbeton werden in Abhängigkeit von der resultierenden Last im Bauteil durchgeführt. Um aus der Vielzahl möglicher Varianten von Bewehrungsstrukturen die passenden auszuwählen, wird ein reduziertes Beschreibungsschema zur Auswahl herangezogen. Als Anwendungsbeispiel wird eine komplexe Bewehrungsstruktur beschrieben, die für dünnwandige, selbsttragende Sandwichelemente genutzt wird. Die Sandwichelemente werden als Wandund Dachkonstruktion für ein 20 m² großes modulares Gebäude eingesetzt. Die Bewehrungsstrategie für die Elemente sowie die Herstellungstechnik und Prüfverfahren für die Bewehrung werden beschrieben. Zur Langzeitüberwachung der Sandwichelemente wird ein Monitoring-System verwendet.
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Patel, Critesh. "Development of discontinuous fibre preforming processes." Thesis, University of Nottingham, 2013. http://eprints.nottingham.ac.uk/13799/.
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Discontinuous fibre composites are under increasing investigation for structural and semi-structural components as they are easily automated, making it possible to remove costly hand labour based steps typically associated with advanced fibre reinforced composites. Directed fibre preforming (DFP) is one possible process which has several advantages when compared with competing techniques. Low material and process costs coupled with short cycle times means the process is suited to medium volume production (typically <10,000 ppa). Predicting mechanical performance remains a major obstacle to industrial adoption however, due to the stochastic nature of fibre distribution. This is of particular importance for structural applications where minimum property requirements and a greater certainty of performance must be achieved. This thesis employs a stochastic macroscale modelling approach to predict fibre locations during the reinforcement deposition stage. This is achieved through process characterisation studying the effects of key microstructural and process-specific parameters on fibre distribution and orientation. The proposed DFP simulation software can generate realistic fibre networks for complex three-dimensional component geometries providing feedback on preform quality. This information is used to optimise the preform structure via process input parameters such as robot trajectory and material properties with validation tests conducted to assess model accuracy. An interface between the simulation software and commercial finite element code facilitates mechanical property analysis for full-scale components using realistic load cases. The complete software package is intended to streamline the route to manufacture for DFP processes from a conceptual design stage.
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Grundmann, Tim Christian. "Automatisiertes Preforming für schalenförmige komplexe Faserverbundbauteile." Aachen Shaker, 2009. http://d-nb.info/995847819/04.
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Jetavat, Dhavalsinh. "Near net shape preforming by 3D weaving process." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/near-net-shape-preforming-by-3d-weaving-process(bb697182-f424-480b-963a-dc49b84425c6).html.
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Significant proportion of composite industry is currently produced using prepregs, cured in autoclave which is very expensive and time consuming process. Dry textile preforms in conjunction with liquid molding techniques can lead to significant reductions in material costs, manufacturing costs and cycle times. These dry preforms are typically 2D woven or braided fabrics which also required lay-up and have low interlaminar properties. Through thickness reinforcement provides solution for this problem as it gives better interlaminar properties as well as near net shape performing. Various 3D performing methods are discussed and reviewed in this research where 3D weaving comes out as ideal process to develop near net shape preforms with more efficiency and better material performance. This research highlights the advantages and limitations of conventional 3D weaving processes. A number of approaches for improving the flexibility of 3D weaving process have been presented including changing fiber architecture in different sections of the preform, tapering in the width and thickness directions and finally to change the fiber orientation. It is concluded that multi step and taper fabrics can be produced on conventional weaving by some modifications. Furthermore, a novel 3D weaving machine is designed and developed after reviewing various patents and weaving methods to overcome limitations of conventional weaving machine. Key criterions from limitations of conventional weaving processes are considered and modified such as multiple weft insertion, limited warp stuffer movement, linear take-up to develop 3D weaving machine. In order to achieve isotropic material, two textile technologies are combined to get final requirements. 3D weaving can provide us fibres in 0° and 90° direction with through thickness reinforcement, whereas braiding can satisfy the requirement of bias direction fibres. Near net shape preforms such as taper and multistep are produced and laminated. Preliminary testing is performed on these laminates to evaluate fibre architectures. Further work is required in terms of machine modification which can provide weave design flexibility to explore various multilayer weave architectures. Thorough testing is required to evaluate and define structure performance and effect of fibre damage during weaving process.
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Grundmann, Tim Christian [Verfasser]. "Automatisiertes Preforming für schalenförmige komplexe Faserverbundbauteile / Tim Christian Grundmann." Aachen : Shaker, 2009. http://d-nb.info/1159832900/34.
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Fong, Lihwa. "Analysis of fiber mat preforming in liquid composite molding /." The Ohio State University, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487779914825982.
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Grieser, Timo [Verfasser], and Peter [Akademischer Betreuer] Mitschang. "Textiles Formgebungsverhalten beim kontinuierlichen Preforming / Timo Grieser ; Betreuer: Peter Mitschang." Kaiserslautern : Technische Universität Kaiserslautern, 2017. http://d-nb.info/1139253204/34.
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Wiggers, Joram. "Analysis of textile deformation during preforming for liquid composite moulding." Thesis, University of Nottingham, 2007. http://eprints.nottingham.ac.uk/10414/.
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Fibre Reinforced Plastics offer several advantages over other materials such as decreased part counts, weight savings, and flexibility. The obstacles to the further expansion of composites use, particularly in cost-conscious industries such as the car industry, include volume, cost, and quality. Liquid Composite Moulding, where the dry textile reinforcement is shaped prior to application of the plastic matrix, offers to address these drivers by offering potential for automation, speed, and quality control. However, the preforming of the dry reinforcement is rarely automated, and its results are variable and hard to predict or control. This thesis aims to facilitate better preforming process design and control. The dominant deformation mechanism that allows reinforcements to conform to a 3D surface is trellis shear. Work is therefore presented on shear characterisation of textile reinforcements using the picture frame and the bias extension tests. Several approaches to normalising these tests to achieve method-independent shear data are proposed, and compared. Of these, a normalisation technique for the bias extension test based on energy considerations appears to be the most appropriate. A constitutive modelling approach, based on the meso-mechanical deformation mechanisms identified in the reinforcement, is developed for characterising the asymmetric shear properties exhibited by non-crimp fabrics. The results from this model are compared with experimental data. Finally, an energy minimising kinematic drape method is developed to account for the use of automated reinforcement blank-holders, and methods for modelling process variability using the code are investigated.
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Shih, Chih-Hsin. "Liquid composite molding of tackified fiber reinforcement : preforming and void removal /." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488202678774704.
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Glenn, John Kirtley. "Comparisons across countries : public policy and the preforming arts in the 1980's." Oberlin College Honors Theses / OhioLINK, 1988. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin1332175944.
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Bardl, Georg. "Entwicklung eines Verfahrens zur zerstörungsfreien Messung der Faserorientierung in mehrlagigen 3D-Carbonfaserpreforms und CFK mit robotergeführter Hochfrequenz-Wirbelstromprüftechnik." Verlag Dr. Hut GmbH, 2018. https://tud.qucosa.de/id/qucosa%3A33892.
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Carbonfaserverstärkten Kunststoffen (CFK) erzielen ihre herausragende Festigkeit und Steifigkeit durch exakte Anpassung der Faserverläufe im Bauteil an die im Einsatz wirkenden Belastungen. Für eine Qualitätskontrolle und eine Optimierung der Fertigungsverfahren ist daher ein Verfahren notwendig, das in der Lage ist, die Faserorientierung in 3D-Preforms (mehrlagigen, drapierten Vorformlingen aus trockenen Carbonfasern) und 3D-CFK zerstörungsfrei zu messen und mit der Soll-Faserorientierung zu vergleichen. Die derzeit für die Faserorientierungsmessung eingesetzten optischen bzw. Röntgen-CT-Verfahren sind hierfür nur beschränkt geeignet, da optische Verfahren auf die oberste Lage und Röntgen-CT-Verfahren auf Kleinproben beschränkt sind.
In dieser Arbeit wird daher ein Verfahren entwickelt, das die Faserorientierung in mehrlagigen 3D-Carbonfaserpreforms und -CFK zerstörungsfrei messen kann. Grundlage hierfür ist die Hochfre-quenz-Wirbelstromprüfung, die eine Darstellung der Verläufe der leitfähigen Carbonfäden in den einzelnen, übereinander gestapelten Lagen des CFK erlaubt. Um hierauf aufbauend eine vollauto-matische Faserorientierungsmessung zu schaffen, wird in einem ersten Schritt ein Roboter-Bahnplanungsverfahren zur vollständigen Erfassung komplex geformter 3D-Oberflächen entwi-ckelt. Aus dem erhaltenen 3D-Wirbelstrombild der Oberfläche wird anschließend über einen auf lokaler Abwicklung und Fouriertransformation beruhenden Algorithmus die lokale Faserorientie-rung in den einzelnen Lagen gemessen und die 3D-Verläufe einzelner Fäden werden rekonstruiert.
Die Messunsicherheit des Verfahrens wird anhand systematischer experimenteller Untersuchungen an 2-, 4-, 6- und 8-lagigen 2D-Gelegestapeln quantifiziert. Untersucht wird hierbei auch der Einfluss der Materialparameter (Gelegetyp) sowie der Messparameter (Spulenanordnung, Spulendurch-messer, Sensororientierung, Messfrequenz) auf die sich ergebende Messunsicherheit, woraus Empfehlungen für die Wahl von Sensor und Messfrequenz abgeleitet werden.
Das entwickelte Messverfahren wird anschließend an zwei 3D-Anwendungsfällen validiert. Als erster Anwendungsfall wird ein vierlagiges, komplex geformtes CFK-Bauteil betrachtet. Es wird gezeigt, wie mithilfe des entwickelten Messverfahrens die Faserorientierung aller vier Lagen zerstörungsfrei erfasst werden kann. Verschiedene Exemplare desselben Bauteils werden hinsicht-lich der Faserorientierung verglichen. Anschließend wird im zweiten Anwendungsfall ein automati-scher Drapierprozess zu einer Halbkugel betrachtet, bei dem verschiedene, ein-, zwei und vierlagi-ge textile Halbzeuge hinsichtlich der sich ausbildenden Faserorientierung nach der Drapierung verglichen werden, mit dem Ziel, das Verformungsverhalten mehrlagiger Strukturen besser zu verstehen und Empfehlungen für die Halbzeugauswahl abzuleiten.
In einem abschließenden Schritt werden Schnittstellen geschaffen, um die Faserorientierungsmes-sung in den CFK-Entwicklungsprozess zu integrieren. Zum einen wird durch eine Schnittstelle zur Drapiersimulation ein quantitativer Vergleich zwischen vorausgesagter und Ist-Faserorientierung möglich, zum anderen wird gezeigt, wie die gemessenen Faserorientierungen der Einzellagen direkt zur Parametrierung von Struktursimulationen verwendet werden können. Das entwickelte Verfah-ren ermöglicht damit eine fundierte Festigkeits- und Steifigkeitsanalyse mit den zerstörungsfrei gemessenen Faserorientierungen nach dem Umformprozess.:1 Einleitung
2 Grenzen bestehender Verfahren zur Faserorientierungsmessung bei der CFK-Herstellung
3 Stand der Technik zur Wirbelstromprüfung von Carbonfasermaterialien
4 Entwicklung einer Roboter-Bahnplanung zur vollständigen Erfassung einer 3D-Oberfläche
5 Entwicklung einer Faserorientierungsmessung aus 3D-Wirbelstromdaten
6 Experimentelle Untersuchung der Messunsicherheit an 2D-Gelegestapeln
7 Verfahrenserprobung an mehrlagigen 3D-Preforms und CFK
8 Integration der Faserorientierungsmessung in den CFK-Entwicklungsprozess
9 Zusammenfassung und AusblickThe superior strength and stiffness of carbon fiber reinforced plastics (CFRP) results from an exact adaptation of the component’s fiber orientation to the external loads during service. Quality control, as well as development and optimization of the production processes, thus require a method to non-destructively measure the fiber orientation in 3D preforms (draped multilayer stacks made of dry carbon fibers) and CFRP. Currently, this fiber orientation measurement is done by optical or X-ray computer tomography methods, which are limited, however to the uppermost, optical visible fabric layer (optical methods) or to small sample sizes (X-ray computer tomography). Therefore, this thesis develops a method to non-destructively measure the 3D fiber orientation in multi-layer 3D preforms and CFRP. The starting point for this development is the technique of high-frequency eddy current testing, which allows an imaging of the individual carbon yarn courses in multiple stacked textile layers. In order to develop a fully-automated fiber orientation measure-ment process with this technique, in a first step a robot path planning is developed that allows the complete scanning of a complexly-shaped 3D surface with an eddy current sensor. From the resulting 3D eddy current image of the surface, the local fiber orientation of the individual layers is measured by local development (flattening) of the surface and a Fourier transformation. The uncertainty of measurement for this method is quantified from experiments with 2-, 4-, 6- and 8-layer 2D non-crimp fabric stacks. The influence of the material parameters (type of fabric) as well as of the measurement parameters (sensor type, coil diameter, sensor orientation, measure-ment frequency) is evaluated. Recommendations for the choice of sensor and measurement frequency are derived. The developed measurement method is subsequently validated with two different 3D application cases. As a first application case, a four-layer, complexly-shaped CFRP component is analyzed. It is shown how the developed measurement method can be used to non-destructively measure the fiber orientation of all four layers. Different specimen of the same CFRP component are compared regarding fiber orientation. The second application case is an automated draping process to a hemispherical shape, for which one-, two- and four-layer textile fabrics are compared regarding the fiber orientation after draping, in order to better understand the forming properties of multi-layer structures and derive recommendations for the choice of textile. In the final step, software interfaces are developed to integrate the fiber orientation measurement into the CFRP design and development process. It is integrated with a draping simulation, to allow a quantitative comparison of the predicted and the measured fiber orientations. Furthermore, it is shown how the measured fiber orientation of the individual fabric layers can be used for the parametrization of finite element structural simulations. The developed measurement method thus lays the base for a substantiated strength and stiffness analysis based on the component’s actual as-is fiber orientation after the draping process.:1 Einleitung 2 Grenzen bestehender Verfahren zur Faserorientierungsmessung bei der CFK-Herstellung 3 Stand der Technik zur Wirbelstromprüfung von Carbonfasermaterialien 4 Entwicklung einer Roboter-Bahnplanung zur vollständigen Erfassung einer 3D-Oberfläche 5 Entwicklung einer Faserorientierungsmessung aus 3D-Wirbelstromdaten 6 Experimentelle Untersuchung der Messunsicherheit an 2D-Gelegestapeln 7 Verfahrenserprobung an mehrlagigen 3D-Preforms und CFK 8 Integration der Faserorientierungsmessung in den CFK-Entwicklungsprozess 9 Zusammenfassung und Ausblick
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Nosrat, Nezami Farbod [Verfasser]. "Automatisiertes Preforming von Kohlefaserhalbzeugen mit aktiven Materialführungssystemen zur Herstellung komplexer Faserverbundstrukturen / Farbod Nosrat Nezami." Berlin : epubli GmbH, 2015. http://d-nb.info/107567686X/34.
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Nezami, Farbod Nosrat [Verfasser]. "Automatisiertes Preforming von Kohlefaserhalbzeugen mit aktiven Materialführungssystemen zur Herstellung komplexer Faserverbundstrukturen / Farbod Nosrat Nezami." Berlin : epubli GmbH, 2015. http://nbn-resolving.de/urn:nbn:de:101:1-2015082118767.
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Tran, Luu Materials Science & Engineering Faculty of Science UNSW. "Effect of knitting and preforming parameters on mechanical properties of weft knitted glass/epoxy composites." Publisher:University of New South Wales. Materials Science & Engineering, 2009. http://handle.unsw.edu.au/1959.4/43515.
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Weft knitted composites have a very complex reinforcement structure which affects their mechanical behaviour. Six kinds of weft knitted fabric reinforcement were examined in this study. These were a group of knitted reinforcements without inlays: Rib, Milano and Interlock and a group with inlays: Rib Inlay, Milano Inlay and Interlock Inlay. The knitting and performing parameters were varied but the fibre volume fraction was kept constant within the two groups. In all cases the fibre used was E-glass. After knitting, the fabrics were infused with epoxy resin using a resin transfer moulding (RTM) process. The mechanical properties of the cured composites were then determined in the wale direction using the tension test, compression test, flexural test, short beam shear test and Izod impact test. The results showed that the knitting and preforming parameters strongly influenced the mechanical properties of the weft knitted glass/epoxy composites.
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Coutandin, Sven [Verfasser], and J. [Akademischer Betreuer] Fleischer. "Prozessstrategien für das automatisierte Preforming von bebinderten textilen Halbzeugen mit einem segmentierten Werkzeugsystem / Sven Coutandin ; Betreuer: J. Fleischer." Karlsruhe : KIT-Bibliothek, 2020. http://d-nb.info/1212512383/34.
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Rohatgi, Vivek. "Liquid Molding of Textile Reinforcements: Analysis of Flow Induced Voids and Effect of Powder Coating on Preforming and Moldability /." The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487931512618085.
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DiGirolamo, Elizabeth Morgan. "The contradiction of the modern Cuban nation the institutionalization of a national hybrid identity, danza moderna, and spaces of blackness in revolutionary performance spheres /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2008. http://wwwlib.umi.com/cr/ucsd/fullcit?p1453652.
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Thesis (M.A.)--University of California, San Diego, 2008.Title from first page of PDF file (viewed July 30, 2008). Available via ProQuest Digital Dissertations. Includes bibliographical references (p. 133-136).
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Leblebici, Robin. "Development of an automated adjusting process for robotic end-effectors to handle dry textiles for preforming of carbon fiber reinforced plastics." Thesis, Luleå tekniska universitet, Rymdteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-67935.
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In order to fulfill increasing production rates, new automated production technologies are required for manufacturing carbon fiber reinforced plastic components for the aerospace industry. Currently, large, double curved composite components have to be manufactured manually, which leads to high process times and poor scalability. As a consequence, a team of cooperating robots with passively adjustable end-effectors was developed, that is capable of handling dry carbon textiles and can be used for layups in double curved molds. This thesis deals with the implementation of a robot program, that performs an automated adjustment of each end-effector to the surface geometry of the manufactured part. The functional principle and the accuracy of the process are evaluated. Further, the automatically adjusted end-effectors are utilized to cooperatively layup carbon plies. The results show, that the accuracy of the automated adjusting process is sufficient to drape carbon fabrics during pick-up and automated layup is possible with this approach. In conclusion, the developed process can be integrated into a fully automated process for future experiments, but hardware inaccuracies should be improved, in order to further enhance the accuracy of the system.
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Sakka, Aymen. "Investigation of Heat Conduction Through PMC Components Made Using Resin Transfer Moulding." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/23508.
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The increasing demand for polymer matrix composites (PMCs) from the airframe industry raises the issues of productivity, cost and reproducibility of manufactured PMC components. Performance reproducibility is closely related to the manufacturing technique. Resin transfer moulding (RTM) offers the advantage of flexible manufacturing of net-shape PMC components with superior repeatability starting from ready-to-impregnate dry reinforcements. An RTM apparatus was developed for manufacturing PMC plates and demonstrator components representative of actual, PMC components and PMC moulds made and used in the airframe industry. The RTM process developed in this work involved making net-shape dry carbon fibre preforms and impregnating them an epoxy resin, targeting mould applications. Thermal repeatability of different net-shape PMC components manufactured using the RTM apparatus developed in-house was investigated. Effects of bonding an outer copper plate onto the PMC material, targeting mould applications known as integrally heated copper tooling (IHCT), were explored. Heat conduction through the PMC components was studied using simulation models validated by experimental data obtained primarily by thermography. Manufactured PMC components showed good repeatability, particularly in terms of thermal behaviour. The IHCT technique was found to be well suited for mould applications. Expected advantages of thermography were materialised. Finally, the simulation models developed were in good agreement with experimental data.
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Mallach, Annegret, Frank Härtel, Frieder Heieck, Jan-Philipp Fuhr, Peter Middendorf, and Maik Gude. "Experimental comparison of a macroscopic draping simulation for dry non-crimp fabric preforming on a complex geometry by means of optical measurement." Sage, 2017. https://tud.qucosa.de/id/qucosa%3A35794.
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Scope of the presented work is a detailed comparison of a macroscopic draping model with real fibre architecture on a complex non-crimp-fabric preform using a new robot-based optical measurement system. By means of a preliminary analytical process design approach, a preforming test centre is set up to manufacture dry non-crimp-fabric preforms. A variable blank holder setup is used to investigate the effect of different process parameters on the fibre architecture.The real fibre architecture of those preforms is captured by the optical measurement system, which generates a threedimensional model containing information about the fibre orientation along the entire surface of the preform. The measured and calculated fiber orientations are then compared with the simulation results in a three-dimensional overlay file. The results show that the analytical approach is able to predict local hot spots with high shear angles on the preform. Macroscopic simulations show a higher sensitivity towards changes in blank holder pressure than reality and limit the approach to precisely predict fibre architecture parameters on complex geometries.
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Velasquez, Scott E. "Images of gender arrangements of three American social organizations: a content analysis of top ranked Google images of individuals preforming organizational roles." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/32872.
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Doctor of PhilosophyDepartment of Sociology, Anthropology, and Social Work
Don L. Kurtz
This study explores existing beliefs and often unspoken social structural arrangements related to male privileges by examining three different, but rather important, American social organizations—the NFL, U.S. military and higher education institutions. With queries from the Google image database, I analyzed images for themes from search terms of organizations thereby tapping into the consciences of society. Since a high volume of images are produced by Google Image search, a maximum of 25 results of each search term are included as potential sources of images for this study. The primary category of non-specific gender search terms of Google images are: NFL Players, U.S. soldiers, and college students. In addition, this study also utilized a subset category of gender and sexuality specific Google search terms that are related to the primary category search terms. The subset category of gender and sexuality specific Google search terms of images are: women of the NFL, NFL gay players, U.S. female soldiers, U.S. gay soldiers, college volleyball players, and fraternity life. Both the U.S. military and the NFL presented images of men preforming competitive or aggressive activities that can be defined as masculine labors. These images are reflections of the ideal masculine male playing a special role in U.S. society—the “warrior” male. Yet most images depicted U.S, soldiers in clean combat uniform with military weapons at a ready to engage in battle. This suggests that either U.S. military have some control over images that can be displayed on popular websites. Even though page ranking software gives the appearance that popular websites are the product of algorithm but there is some evidence that ranking can be manipulated by organizations. Colleges take manipulating popular websites to another level to reach their potential clients. Unlike the U.S. military and the NFL’s search terms results that presented images of men preforming masculine activities, college students’ search term results images are images of students displaying activities that show individuals in the act of being polite and pleasant to others, as well as being supportive. I suggest that the idea behind presenting images with a feminine slant is to attract the group that is most likely to attend college after high school, which is female. College websites will most likely to have staged images of study groups and professors teaching to a small group of students. The websites featured staged images of students, in which students are almost flawless in appearance, a phenomena that could only be achieved through doctoring, cosmetics, and computer retouching. This type of images is more likely to be attractive to potential students that are searching the internet for potential colleges to attend in the future. Moreover, Photoshop images of students assist colleges and universities in controlling the images they want to introduce to potential students and media. Colleges are prudent on how much to display in images of heterosexual relationships. Most staged images that displayed heteronormativity are male and female students studying within each other personal space. It would seem that images of homosexual relationships are still taboo on college websites because there are no staged images that indicated homosexual relationship between college students. I believe that these reflections are presented as organizational websites’ marketing strategies. The marketing strategies of website designers are to implement a group think mentality of those seeking information of a specific term. This action is caused by search engine page ranking software in order to organize highly interconnected websites toward one idea thus influencing a large number of potential and current customers’ decisions. In today’s technologically connected society, societal perception of what constitutes masculinity, femininity and sexuality starts with a well-designed website. The findings will perhaps have important implications for understanding to how the negative outcomes of male privileges remain entrenched in social institutions and benefit certain segments of society at the cost of others.
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Coutandin, Sven [Verfasser]. "Das Stempel-Preforming in der Binder-Umformtechnik bietet ein großes Potential zur Fertigung komplexer, schalenförmiger Preforms, was ein Schlüsselprozess in der Herstellung von endlosfaserverstärkten Bauteilen darstellt. Ein innovativer Ansatz zur Verbes / Sven Coutandin." Düren : Shaker, 2020. http://d-nb.info/1213472741/34.
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Lee, Sang Won. "Audience participation using mobile phones as musical instruments." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44749.
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This research aims at a music piece for audience participation using mobile phones as musical instruments in a music concert setting. Inspired by the ubiquity of smart phones, I attempted to accomplish audience engagement in a music performance by crafting an accessible musical instrument with which audience can be a part of the performance. The research begins by reviewing the related works in two areas, mobile music and audience participation at music performances, builds a charted map of the areas and its intersection to seek an innovation, and defines requisites for a successful audience participation where audience can participate in music making as musicians with their mobile phones. To make accessible audience participation, the concept of a networked multi-user instrument is applied for the system. With the lessons learnt, I developed echobo, a mobile musical instrument application for iOS devices (iPhone, iPad and iPod Touch). With this system, audience can download the app at the concert, play the instrument instantly, interact with other audience members, and contribute to the music by sound generated from their mobile phones. A music piece for echobo and a clarinet was presented in a series of performances and the application was found to work reliably and accomplish audience engagement. The post-survey results indicate that the system was accessible, and helped the audience to connect to the music and other musicians.
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Tröltzsch, Jürgen [Verfasser]. "Spritzgießtechnische Direktimprägnierung textiler Halbzeuge und Preformen bei komplexen Hochleistungsbauteilen / Jürgen Tröltzsch." München : Verlag Dr. Hut, 2012. http://d-nb.info/1028784090/34.
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Heß, Christoph [Verfasser]. "Beitrag zur Qualitätssicherung für die serientaugliche Herstellung von textilen Preformen / Christoph Heß." München : Verlag Dr. Hut, 2016. http://d-nb.info/1097817792/34.
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Neumann, Ulf Henning [Verfasser], and Peter [Akademischer Betreuer] Mitschang. "Kontinuierliches Ultraschall-Preformen zur Fertigung von CFK-Bauteilen in der Luftfahrt / Ulf, Henning Neumann ; Betreuer: Peter Mitschang." Kaiserslautern : Technische Universität Kaiserslautern, 2017. http://d-nb.info/1167236971/34.
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Heß, Christoph Verfasser], Klaus [Akademischer Betreuer] Drechsler, and Thorsten [Akademischer Betreuer] [Schüppstuhl. "Beitrag zur Qualitätssicherung für die serientaugliche Herstellung von textilen Preformen / Christoph Heß. Betreuer: Klaus Drechsler. Gutachter: Klaus Drechsler ; Thorsten Schüppstuhl." München : Universitätsbibliothek der TU München, 2016. http://d-nb.info/1088724833/34.
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Heß, Christoph [Verfasser], Klaus Akademischer Betreuer] Drechsler, and Thorsten [Akademischer Betreuer] [Schüppstuhl. "Beitrag zur Qualitätssicherung für die serientaugliche Herstellung von textilen Preformen / Christoph Heß. Betreuer: Klaus Drechsler. Gutachter: Klaus Drechsler ; Thorsten Schüppstuhl." München : Universitätsbibliothek der TU München, 2016. http://nbn-resolving.de/urn:nbn:de:bvb:91-diss-20160201-1246228-1-3.
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WU, HAW-JONG, and 吳顥中. "The History of Street Preforming Arts in Ancient China." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/7x92pm.
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碩士東吳大學
中國文學系
106
The earlist record of street perform in China is from Tang Dynasty.However,we don’t know that how does the street show appear? How does this culture develop? No one in the current academic research studies this culture. I am a street performer,so I want to research the history of my job. This paper is consisted of 5 chapters. Chapter 1 is research that how does the street show appear? Chapter 2 is the research of the show in ancient China. Chapter 3 is research about the “pitch”(the space of street show) in ancient China. Chapter 4 is the research of the Busker’s social status. Chapter 5 is the research of Taiwanese buskers in modern times. The last chapter is the research of the different from ancient and modern,and the value of street show.
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Mao, Chen-Wei, and 毛振偉. "Improvement of Automated Preforming Processing Quality of Power Transistors." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/q7fdqr.
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碩士國立臺北科技大學
管理學院EMBA華南專班
106
With the global industrialization 1.0 transiting to global industrialization 4.0, the production of power supply has also evolved from manual assembly to automatic assembly manufacturing. The pre-manufacturing electronic component preforming processing has significant changes under automation, in which transistor preprocessing evolve from semi-automatic processing to fully automaticed processing. The former, semi-automatic processing, only value quantity while the latter, fully automaticed processing, value both quantity and quality. Automated equipment has raised another challenge: maximize production quality by using intelligent system.This research uses the technology of mechanical transformation as the foundation, cooperating with new electronica machinery technology; using the factor analysis, C&E Matrix, FMEA, multivariate analysis and six sigma standard deviation techniques; coordinating lean manufacturing to search for the optimal structure of automatic preforming processing equipment of power transistor to conduct new generation of automated intelligent equipments.Linking senior process engineers, test engineers, mechanical engineers, quality control engineers to form an expertise team and set up a specialize project in investigating the advantages and disadvantages of existing power transistor preforming processing type and machining. Firstly, find out the key factors by using Process Mapping, Cause & Effect Matrix, Statistical Analysis and Capability, and so on. After that validating the effective factors and making improvements with tools including Multivariate, Correlation, Hypothesis, ANOVA, and FMEA. Design of experiment can be used on more difficult factors to find out the optimal combination of parameters and then apply it on automated preforming processing equipments. Lastly, effect confirmation need to be done to ensure the outcome meet the expectation.The research result, which uses the six sigma standard deviation method, can make for a more comprehensive development of transistor automation equipments that reduce resources wastage, frequent replacement due to inconsiderate automated equipment development. By reaching industrial 4.0 intelligent equipment, the stability of product quality and customer satisfaction can be improved, and hence further reduce the research and development costs and enhance the corporate competiveness.
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Chiang, Yen-Hui, and 江彥輝. "A Study of Preforming Design in the Tube-Hydroforming Process." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/52318388750346612733.
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碩士國立臺灣大學
機械工程學研究所
99
Nowadays, Tube hydroforming (THF) technique has been popularly applied to the car body structural components. The advantages of employing THF process over the conventional stamping and welding process have been lightweight and high strength for the car body structure. There are three operations in a complete THF process, which are tube bending, preforming, and hydro-forming. In the present study, the preforming die design and the loading path adopted in the hydroforming operation for manufacturing a twist beam used in a real axle were examined. In addition, the punch shape for hydro-piercing a scrap-attached hole was also investigated. Both the finite element simulations and the experimental approaches were employed to complete the analysis and die design. Since the twist beam bears a relatively small curvature in one plane, it is difficult to bend the tube by a bending machine and needs to produce the bend in a preforming die. Also due to the deep V-shaped cavity along the curved axis of the twist beam, one or two more preforming operations are required to provide an appropriate preformed tube to the subsequent hydroforming operation. In the present study, the number of preforming operations and the geometry of each prefoming die are determined by the finite element analysis. It is found that three preforming operations are required for hydroforming this curved twist beam if a cam mechanism is not involved in the preforming operation. In addition, different loading paths are designed for the hydroforming operation to investigate the formability of this twist beam using the finite element simulations. Based on the finite element analysis, an optimum single-step loading path was established. However, a two-step loading path that would improve the maximum thinning a little bit was also developed. As for the hydro-piercing operation, different punch shapes were designed to investigate the hole-piercing performance. The hole-piercing experiments were conducted first in a stamping process without hydraulic pressure acting on the opposite side of the sheet. The appropriate geometry of the punch shape was then applied to the hydro-piercing operation. The finite element simulation results indicate that the proposed punch shape could pierce the hole with the scrap remained in the tube that is required by the part design. The developed preforming die design concept, the loading path used in the hydroforming operation, and the punch shape for the hydro-piercing process could provide a valuable reference to the future study in the tube-hydroforming research field.
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Hsuan-HaoChiu and 邱宣豪. "Study on Preforming of Continuous Bamboo Fiber and Reinforced Epoxy Composite." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/99v779.
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碩士國立成功大學
航空太空工程學系
107
The continuous bamboo fiber (BF) reinforced epoxy (EP) composites were fabricated using bamboo fibers treated in different alkali concentrations. Tensile and interfacial shear strength of these composites were compared to select the alkali concentration for the treatment process that results in a higher strength. The unidirectional and bidirectional BF/EP composites were fabricated using the selected BF alkali treatment process. Tensile properties were measured for the unidirectional and bidirectional BF/EP composites with different fiber volume fractions. The unidirectional BF/EP composite has good reinforcement effect in the fiber direction. However, the measured transverse strength is weaker than the epoxy. For bidirectional BF/EP composites, tensile strengths in both the longitudinal and transverse orientation all shows some improvement as compared to epoxy. In order to fabricate bamboo fiber reinforced composites with non-planar geometric shapes. The study investigated the deformation and spring back behaviors of the single BF and BF mat under a bending preforming test. The result shows that the [0/90] BF mats can be perfectly preformed without spring back after bending under the conditions of a moisture content of 58% and heating temperature of 140°C for 1 hour. The internal structure of BF with moisture will expand and soften that make the fibers to deform plastically under external stresses. The single BF preforming test and stress relaxation test was conducted to confirm the above result. Higher heating temperature and moisture content of BF during preforming process can reduce the spring back effect.
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Gao, Zheng-Sen, and 高政森. "Study of Bend Induced Gap in Fiber Preforming of Woven Fiber Mats." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/01113967210020217347.
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碩士國立成功大學
航空太空工程學系
88
Rein Transfer Molding (RTM) is a widely used method in fabricating the polymer composites. The fabricating process can be divided into four steps: (1) fiber preforming, (2) mold filling, (3) resin curing, (4) demolding. In the fabricating process, fiber preforming and curing are the major steps. High quality of molded products depends on a uniform mold filling pattern. The undesire mold filling pattern usually results from an unadequate preforming process. One of the consequence is the channel gap at the bending corner. During the preforming, the fiber may be deformed and detach from the mold at the bending place. In present study, the goal is to study the effect of fiber bending angle on the variation of fiber thickness, and thus the possibility of forming channel gaps. By controling the fiber bending angle, mold thickness, and porosity, we can observe the variation of fiber thickness at the bending place. By the developed bending model, we can predict the variation of fiber thickness, which provides a guide for mold design at the bending place.
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LIAO, Jei-Chi, and 廖瑞琦. "Polymer Transfer Molding Technology-Analysis of Preforming Process and Its Effect on PTM." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/56906338963142763201.
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CAO, ZHI-HAO, and 曹智皓. "Analysis of Rotary Swaging Process for Preforming Process of High Expansion Ratio Bike Tube." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/u858kq.
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碩士國立虎尾科技大學
機械與電腦輔助工程系碩士班
107
With the development of bicycles in recent years, people now are not only satisfied with how convenient and power-saving bicycles are, but also the fancy appearances of bikes. To achieve dramatic deforming of bike frames which are thought more beautiful than simple ones, the extreme high-profile difference which traditional processing method cannot cope with is required. Thus, we use rotary swaging forging which is the best forging method of shrink forming processes as pre-forming in this paper. Then, we use the basic formula evolved by industry experiences to find the basic parameters, and add more severe conditions to the formula to create the circumstances to form extreme high-section difference. In order to reduce costs, FEM is used to simulate the processing to discuss the formability, thickness and appearance of workpieces until finding out the optimization process. The final step is forming the workpiece practically and comparing the results of simulation and actual processing. In this research, it is found that the influence of the billet is very large when it comes to forming limitation. Therefore, to make the differences between the simulation and actual result smaller, the billet is subjected to annealing heat treatment and then the tensile test is performed to obtain the flow stress of the material before the rotary swaging forging in this research. In the part of optimizing parameters, it is found out that when the friction factor is 0.05 and the feed rate is 2.03 mm/s, the thickness of the finished product is relatively thin whether rotary swaging forging value is 0.28 or 0.31. In the comparison of surface roughness, when the rotary swaging forging value is 0.28 or 0.31, the mechanical automatic feeding makes the workpiece have a better surface roughness because it feeds more smoothly than human feeding. Moreover, the surface roughness of products is better when the rotary swaging forging value is 0.28 than it is 0.31, so the processing is more stable when the rotary swaging forging value is 0.28. In the comparison of thickness, it is found that the simulation is thicker than the actual finished product because the cutting occurred in the actual processing, but not in the simulation. Thus, the excess material would flow to the inner surface and make the simulation thicker than the actual workpiece. In the comparison of hardness, the hand-held feeding during the actual processing causes the front end of the material to rub against the die due to the unstable of feeding speed and the strength the feeding force. The friction results in a tendency for the hardness value to become higher and higher, which is the biggest difference between the simulation and the actual result. In the hydroforming simulation, when the thickness of the rotary forged product is less than 4mm, the internal pressure can make the billet completely fit on the die. However, if the thickness of the rotary forged product is over 4mm, hydroforming will cause the billet to expand slightly and the material cannot fit on the die. Therefore, it is very important for hydroforming to control the thickness of the pre-forming workpiece.
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WU, HUI-LI, and 吳慧麗. "A Study of Teaching Effect on the Application of Image Theatre in Preforming Arts Course Integrated into the Issue of Indigenous Education: Taking a Sixth Grade in Taitung County for Example." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/44k84a.
Full textAbstract:
碩士國立臺灣藝術大學
表演藝術教學碩士學位班
106
The study aims to examine the feasibility of using image theatre as a pedagogical method in indigenous education in elementary school, exploring whether incorporating the method in teaching plans could increase indigenous students’ understanding of their own culture and, in turn, develop their ethnic identity. The author of the study is an Amis, one of Taiwan’s indigenous peoples, and teaches in Taitung City at an elementary school where about 80% of the students are aboriginal. From teaching the students it was discovered that they had little knowledge about their own culture. Influenced by TV and other media, the students were deeply attracted to pop culture from South Korea and the West; they had no interest in their own culture, nor did they attach any importance to it. It was hoped that integrating theatre into teaching strategies could motivate the students to learn about indigenous peoples and grew interested in the topic, and that the theatrical experience would stimulate them to think about issues relevant to them and increase their ethnic identity. The research took a case-study approach, with 16 six-graders in the author's class as research subjects. Performance art lesson plans that incorporated indigenous issues were designed for and used in eight class sessions. Observation were made and records kept about whether and how the eight-graders increased their ethnic identity after image theatre was used in teaching strategies to include indigenous education in the learning field of arts and cultures. The researcher triangulated various data including student worksheets, questionnaires, interviews, the teacher’s log, and audio-visual recordings of the class sessions and also talked with observing teachers and experts to analyze teaching goals and effectiveness. It has been concluded that image theatre as a pedagogical approach to incorporating indigenous education in performance art classes improved several constructs of the students’ ethnic identity: awareness, self-identification, attitude, behavior, and sense of belong. Ethnic identity was established since the approach effectively increased the students’ understanding of indigenous culture and stimulated them to think about issues relevant to themselves.