1,720,954 research outputs found
Additive Manufacturing for the supply chain of spare parts in the automotive and aircraft industry
Get PDFDas Ziel dieser Arbeit ist es, das Potential des 3D-Drucks in konkreten Anwendungsgebieten der Ersatzteilversorgung der Automobil- und Luftfahrtindustrie aufzuzeigen. Bei der Betrachtung der Fragestellung wurde unterstellt, dass der Markt der beiden Industrien viele noch ungenutzte Potentiale bietet.
Der 3D-Druck hat sich in den letzten Jahren hinsichtlich Druckqualität und Druckzeit stark weiterentwickelt und hat den Sprung vom Fertigungsverfahren für Prototypen zum Fertigungs-verfahren auch für die Serienproduktion geschafft. Die Luftfahrtindustrie zeigt bereits erste Beispiele von Serienteilen aus einem additiven Herstellungsprozess.
Mit einer detaillierten Betrachtung der vier Themengebiete 3D-Druck, Ersatzteile, Automobil-industrie, Luftfahrtindustrie sollen die wichtigsten Kriterien jedes Gebietes erklärt werden. Das Wissen aus den geführten Experteninterviews unterstützt die Wahl der betrachteten Merkmale jedes Themengebiets. Auf dessen Basis wurde ein Bewertungskatalog erstellt, in dem sich die angesprochenen Merkmale wiederfinden. Der Bewertungskatalog ist die Grundlage für die Analyse von Beispielen aus den beiden betrachteten Industrien, für das Potential den 3D-Druck für die Ersatzteilproduktion einzusetzen.
Die limitierte Literatur zu diesem speziellen Einsatzfall der noch neuen Fertigungstechnologie wurde mit Sekundärquellen und ingenieurmäßigen Abschätzungen komplementiert.
Die Analyse der Beispiele zeigt in der Automobilindustrie, dass der Einsatz des 3D-Drucks vor Allem durch eine Reduktion von Wertschöpfungskosten gerechtfertigt werden kann, aber auch durch das Schaffen von Individualität für Nischenmärkte. In der Luftfahrtindustrie haben zwar auch die Wertschöpfungskosten einen wesentlichen Einfluss auf die Wahl der Fertigungsmethode, aber in starkem Maße auch die Faktoren Leichtbau und Wiederbeschaffungszeit
Additive manufacturing for the spare part management of classic cars
Get PDFThesis (MEng)--Stellenbosch University, 2022.ENGLISH ABSTRACT: The maintenance of older vehicles can be challenging since the supply of spare parts by the original equipment manufacturer is not guaranteed throughout the lifespan of a vehicle. Thus, there is a need to improve the current spare part supply chain for the automotive industry specifically for outdated products like classic cars. Within the automotive industry additive manufacturing (AM) technology is already being implemented in the production cycle of new cars. The need to improve the supply of spare parts for classic cars and the increased use of the AM technology raised the question whether additive manufacturing can have an impact on the spare part management of classic cars. In order to answer this question, this research study started with the review of literature.
Three critical scoping literature reviews were undertaken to analyse the current performance of the spare part management of classic cars and to identify spare part attributes for the ranking of spare parts according to their potential for additive manufacturing. To fully understand the spare part management of classic cars, a first literature study on the classic car market was conducted. A second literature review on spare part management within the automotive industry utilized a performance measurement model to measure the impact of adopting additive manufacturing. Based on this, the applicability of additive manufacturing was the subject of the third literature review. Results show that a potential for additive manufacturing exists, and it can be measured with spare part attributes. Based on these results, it was decided to follow an exploratory research design approach.
A survey was conducted with classic car owners to identify sourcing problems of spare parts and to assess their willingness to adopt additive manufacturing. The data from the survey was analysed using a ranking methodology from science which was modified toward the application of additive manufacturing on the spare part management of classic cars. The outcome of the ranking highlighted that small parts (e.g. switches) and batches are best suitable for additive manufacturing. A Delphi survey with subject-matter experts validated the ranking method. A case study was carried out in which a speedometer gear was reverse-engineered, additive manufactured and tested under realistic conditions. The case study highlighted that additive manufacturing is feasible to produce spare parts on demand and on a decentralized implementation strategy.
Overall, this research has shown that additive manufacturing has a high potential to impact the spare part management of classic cars. The research result showed that unsatisfied customer demand is recognised. Additive manufacturing is a technologically feasible solution to produce many spare parts and has the high potential to increase the supply chain performance of classic car spare parts.AFRIKAANSE OPSOMMING: Die instandhouding van ouer voertuie kan uitdagend wees aangesien die verskaffing van onderdele deur die oorspronklike toerusting vervaardiger nie deur die lewensduur van 'n voertuig gewaarborg word nie. Daar is dus 'n behoefte om die huidige onderdele-voorsienings ketting vir die motorbedryf te verbeter, spesifiek vir verouderde produkte soos klassieke motors. Binne die motorbedryf word additive manufacturing (AM) tegnologie reeds in die produksie siklus van nuwe motors geïmplementeer. Die behoefte om die verskaffing van onderdele vir klassieke motors te verbeter en die verhoogde gebruik van die AM-tegnologie het die vraag laat ontstaan of bykomende vervaardiging 'n impak op die onderdelebestuur van klassieke motors kan hê.
Drie kritiese literatuur oorsigte is onderneem om die huidige prestasie van die onderdele bestuur van klassieke motors te karteer. Eerstens is 'n literatuuroorsig oor die klassieke motormark gedoen. Die volgende twee literatuur oorsigte oor onderdele bestuur binne die motorbedryf en bykomende vervaardiging vir motoronderdele het 'n prestasie metings model gebruik om die impak van die aanvaarding van bykomende vervaardiging te meet. Resultate toon dat 'n potensiaal vir bykomende vervaardiging bestaan. Op grond van hierdie resultate is daar besluit om 'n verkennende navorsings ontwerp benadering te volg.
’n Opname is met eienaars van klassieke motors gedoen om die verkrygings probleme van onderdele te identifiseer en om hul gewilligheid om bykomende vervaardiging aan te neem, te bepaal. Die data van die opname is ontleed deur gebruik te maak van 'n rangorde metodologie uit die wetenskap wat aangepas is na die toepassing van bykomende vervaardiging op die onder delebestuur van klassieke motors. Die uitkoms van die rangorde het beklemtoon dat klein onderdele (bv. skakelaars) en groepe die beste geskik is vir bykomende vervaardiging. 'n Delphi-opname met vakkundiges het die rangorde metode bekragtig. ’n Gevallestudie is uitgevoer waarin ’n spoed-meterrat omgekeerd ontwerp is, ´n bymiddel vervaardig en onder realistiese toestand getoets is. Die gevallestudie het beklemtoon dat bykomende vervaardiging haalbaar is om onderdele op aanvraag en volgens 'n gedesentraliseerde implementering strategie te vervaardig.
Oor die algemeen het hierdie navorsing getoon dat bykomende vervaardiging 'n hoë potensiaal het om die onderdele bestuur van klassieke motors te beïnvloed. Die navorsings resultaat het getoon dat die onbevredigde vraag erken word. Bykomende vervaardiging is 'n tegnologiese haalbare oplossing om baie onderdele te vervaardig en het die hoë potensiaal om die voorsienings ketting prestasie van klassieke motoronderdele te verhoog.Master
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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