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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.
51

Motivy spotřebitelů k nákupu upcyklované módy / Consumers' Motives for Buying Upcycled Clothes

Bourová, Tereza January 2020 (has links)
The focus of this diploma thesis is on the consumers' motives for purchasing upcycled clothing. Based on the research of available resources, this thesis firstly describes the most expanded model of clothing production, fast fashion, with special focus on the negative environmental impacts it has during different stages of a product life cycle. It later moves on to describe the traditional and more environmentally friendly model, slow fashion, and puts both these concepts (fast fashion and slow fashion) in connection with the hierarchy of waste management and the concept of circular economy. This theoretical base helps to fully understand the concept of upcycled fashion, which is thoroughly described in a separate chapter that also includes various examples of designers who focus on fashion upcycling. The last section of the theoretical part deals with motivation and motives for purchasing clothes. The empirical part of this diploma thesis focuses on how consumers perceive upcycled fashion in order to answer the main research question: What are the consumers' motives for purchasing upcycled clothes? To answer the question, qualitative research was used, specifically semi- structured interviews. The interviews were conducted with a total of twelve shoppers who have had previous personal experience...
52

Neuartige Warmmahltechnologie zum Recycling von Elastomeren und Analyse prozessbedingter Eigenschaften

Hoyer, Stefan 04 December 2014 (has links)
Die Arbeit widmet sich der Problemstellung der Substitution des Primärrohstoffes Kautschuk durch Rezyklate in Form von Gummimehl. Die für das innerbetriebliche Recycling von Kleinchargen technischer Elastomere hier eigens konzipierte und umgesetzte Warmmahltechnologie dient zur Herstellung von Gummimehlrezyklat hoher Qualität aus Lkw-Altreifen. Hinsichtlich ausgewählter Verarbeitungs- und Materialkennwerte von Mischung und Vulkanisat werden die Auswirkungen der Zugabe von Rezyklaten und die wesentlichen Einflussgrößen des den Rezyklaten zugrunde liegenden Aufbereitungsprozesses – das Kryogenmahlverfahren bzw. die neu entwickelte Warmmahltechnologie – herausgearbeitet. Abschließend erfolgt die Formulierung materialspezifischer Versagensmechanismen, die das entsprechende Aufbereitungsverfahren der Rezyklate berücksichtigen.:1 Einleitung 1 2 Stand der Technik 3 2.1 Elastomerrecycling 3 2.2 Warm- und Kaltmahlverfahren 5 2.3 Warmmahlextrusion 8 3 Zielstellung 13 4 Werkstoffmechanische Charakterisierung von Elastomeren 15 4.1 Eigenschaften von Kautschuk und Gummi 15 4.2 Mechanisches Ersatzmodell 16 4.3 Vulkanisation 20 4.3.1 Grundlagen 20 4.3.2 Vernetzungsreaktion 22 4.3.3 Konstitution der Vernetzungsstellen 23 4.3.4 Reversion und „marching modulus“ 25 4.4 Verformungsverhalten 26 4.4.1 Hyperelastizität 26 4.4.2 Hysterese 27 4.4.3 Mullins-Effekt 28 4.4.4 Payne-Effekt 29 4.4.5 Spannungsrelaxation und Spannungsretardation 30 4.5 Zustands- und Übergangsbereiche 31 4.5.1 Temperaturabhängige Zustands- und Übergangsbereiche 31 4.5.2 Zeitabhängige Zustandsbereiche 32 4.5.3 Zeit-Temperatur-Superposition 33 4.6 Gummireibung 35 4.7 Bruchmechanische Ansätze 38 4.7.1 Begriffsdefinitionen 38 4.7.2 Rissinitiierung und Rissausbreitung 39 4.7.3 Rissabstumpfung (Blunting) 41 4.7.4 Einfluss der Verschlaufung der Makromoleküle und der Vernetzungsdichte 46 5 Eigenschaften und Versagensverhalten von Rezyklatcompounds 49 6 Warmmahltechnologie zur Verarbeitung sortenreiner Kleinchargen 53 6.1 Neuer Warmmahlprozess 53 6.2 Verfahrensoptimierung 55 6.3 Technische Elastomere 61 6.4 Ergebnisse der Verfahrensoptimierung 63 7 Untersuchung des Werkstoffverhaltens von Rezyklatcompounds 65 7.1 Charakterisierung der Ausgangsmaterialien 65 7.2 Mischungseigenschaften und Vulkanisationsverhalten 66 7.2.1 Mischungsrezeptur und Mischungsrheologie 66 7.2.2 Flüssig-Fest-Extraktion zur Ermittlung des Sol-Anteils 68 7.2.3 Vulkanisationsverhalten 71 7.3 Vulkanisateigenschaften 72 7.4 Spannungs-Dehnungs-Verhalten 75 7.4.1 Zugversuch nach DIN 53504 75 7.4.2 Zugversuche bei verschiedenen Dehnraten 79 7.5 Bruchflächenmorphologie 87 8 Auswertung der Untersuchungen von Rezyklatcompounds 93 8.1 Auswirkungen der Zugabe von Gummimehlrezyklat in die Kautschukmischung 93 8.2 Versagensmechanismen von Rezyklatcompounds 94 8.3 Vergleich von Rezyklatcompounds mit warm oder kryogen vermahlenem Feinmehl 97 8.4 Rückschlüsse aus der Materialcharakterisierung 99 9 Zusammenfassung und Ausblick 101 10 Literaturverzeichnis 103 11 Anhang 107 / The work is devoted to the problem of the substitution of the primary raw material rubber by recycled materials in the form of rubber powders. For the in-plant recycling of small batches of technical elastomers an ambient grind technology was specifically designed and implemented for making rubber powders of high quality out of used truck tires. In terms of selected processing and material characteristics of the mixture and the vulcanizate the influences of the addition of recycled material and the significant factors affecting the regeneration process underlying these recyclates – the cryogenic grinding versus the new developed ambient grinding technology – were worked out. Finally, the material-specific failure mechanisms were formulated, incorporating the regeneration process of such regenerated materials.:1 Einleitung 1 2 Stand der Technik 3 2.1 Elastomerrecycling 3 2.2 Warm- und Kaltmahlverfahren 5 2.3 Warmmahlextrusion 8 3 Zielstellung 13 4 Werkstoffmechanische Charakterisierung von Elastomeren 15 4.1 Eigenschaften von Kautschuk und Gummi 15 4.2 Mechanisches Ersatzmodell 16 4.3 Vulkanisation 20 4.3.1 Grundlagen 20 4.3.2 Vernetzungsreaktion 22 4.3.3 Konstitution der Vernetzungsstellen 23 4.3.4 Reversion und „marching modulus“ 25 4.4 Verformungsverhalten 26 4.4.1 Hyperelastizität 26 4.4.2 Hysterese 27 4.4.3 Mullins-Effekt 28 4.4.4 Payne-Effekt 29 4.4.5 Spannungsrelaxation und Spannungsretardation 30 4.5 Zustands- und Übergangsbereiche 31 4.5.1 Temperaturabhängige Zustands- und Übergangsbereiche 31 4.5.2 Zeitabhängige Zustandsbereiche 32 4.5.3 Zeit-Temperatur-Superposition 33 4.6 Gummireibung 35 4.7 Bruchmechanische Ansätze 38 4.7.1 Begriffsdefinitionen 38 4.7.2 Rissinitiierung und Rissausbreitung 39 4.7.3 Rissabstumpfung (Blunting) 41 4.7.4 Einfluss der Verschlaufung der Makromoleküle und der Vernetzungsdichte 46 5 Eigenschaften und Versagensverhalten von Rezyklatcompounds 49 6 Warmmahltechnologie zur Verarbeitung sortenreiner Kleinchargen 53 6.1 Neuer Warmmahlprozess 53 6.2 Verfahrensoptimierung 55 6.3 Technische Elastomere 61 6.4 Ergebnisse der Verfahrensoptimierung 63 7 Untersuchung des Werkstoffverhaltens von Rezyklatcompounds 65 7.1 Charakterisierung der Ausgangsmaterialien 65 7.2 Mischungseigenschaften und Vulkanisationsverhalten 66 7.2.1 Mischungsrezeptur und Mischungsrheologie 66 7.2.2 Flüssig-Fest-Extraktion zur Ermittlung des Sol-Anteils 68 7.2.3 Vulkanisationsverhalten 71 7.3 Vulkanisateigenschaften 72 7.4 Spannungs-Dehnungs-Verhalten 75 7.4.1 Zugversuch nach DIN 53504 75 7.4.2 Zugversuche bei verschiedenen Dehnraten 79 7.5 Bruchflächenmorphologie 87 8 Auswertung der Untersuchungen von Rezyklatcompounds 93 8.1 Auswirkungen der Zugabe von Gummimehlrezyklat in die Kautschukmischung 93 8.2 Versagensmechanismen von Rezyklatcompounds 94 8.3 Vergleich von Rezyklatcompounds mit warm oder kryogen vermahlenem Feinmehl 97 8.4 Rückschlüsse aus der Materialcharakterisierung 99 9 Zusammenfassung und Ausblick 101 10 Literaturverzeichnis 103 11 Anhang 107
53

Concept development of a compression molding machine for biocomposite materials / Konceptutveckling av en formpressningsmaskin för biokomposit material

Perttu, Gusten, Larsson, Adam January 2022 (has links)
The growing concern with the environmental impacts of disposable products has placed an emphasis on ensuring the sustainability of material systems. A shift in the selection of material can decrease the negative effects of disposable products. One class of materials with good credentials is biocomposite materials, a material partly consisting of biodegradable products. In this thesis project a compression molding machine suitable for the pressing of biocomposite materials are developed for the start-up Trash to Gold. The start up is in a early process of developing compression molding machine. As of now they use a modified workshop press to test out the pressing of to-go coffee cups made out of biodegradable a biocomposite material partly consisting of coffee grounds. The current press is not optimised for their expected customer group and it is therefore appropriate to develop a new one. The aim of this thesis project is to assist Trash to Gold in their development of a compression molding machine, suitable for upcycling biodegradable waste into disposable products. The objective of this thesis project is to develop a concept of a compression molding machine that can be used to print to-go coffee cups partly made of coffee grounds. The concept to be developed will be for a press that weighs less and has smaller dimensions than the current one to suit the target group. The product development methodology of the project is based on Ulrich and Eppinger’s book ”Product Design and Development”. Some of the approaches used from book are modified for better application on the project. The project also includes digital and theoretical tools to determine if the concept can withstand the pressure generated when the machine is in use. The result of the thesis project is a concept of a compression molding machine that meet requirements given by the start up. Suitable parts for the basic structure of the compression molding machine is presented such as how the pressing function will occur and the outer frame with where the different components will sit. The resulting concept is smaller and more light weight compared to the current machine. / Den växande oron för negativa effekter engångsprodukter har på miljön har lett till ett ökat intresse att säkerställa materialsystemens hållbarhet. En förändring av materialvalet fÅNor produkterna kan minska dessa negativa effekterna. En materialklass som hade kunnat minska de negativa effekterna är biokomposita material. Biokomposit material är ett material som delvis består av biologiskt nedbrytbara produkter. I detta examensarbete utvecklas en formpressningssmaskin anpassad för formpressning av biokomposita material. Projektet görs på uppdrag av startup-företaget Trash to Gold. Företaget håller på att utveckla en formpressningsmaskin och använder just nu en modifierad verkstadspress för att testa tillverkningen av engångskaffemuggar som delvis består av kaffesump. Den nuvarande pressen är inte anpassad för den förväntade kundgruppen och det är därför l'mpligt att utveckla en ny. Syftet bakom detta examensarbete är att hjälpa Trash to Gold att utveckla en formpressningsmaskin som är anpassad för återanvändningen av bionedbrytbara restprodukter till engångsartiklar. Målet med det här examensarbetet är att utveckla ett koncept av en formpressningsmaskin som kan användas för att formpressa engångskaffemuggar delvis bestående av kaffesump. Konceptet som tas fram ska vara för en press som väger mindre och har mindre dimensioner än den nuvarande för att passa målgruppen. Arbetets produktutvecklingsmetodik är baserad på Ulrich och Eppingers (U&E) bok ”Product design and Development”. Exempel på metoder som använts är identifiering av kundbehov, produktspekification, konceptgeneration, extern- och intern undersökning samt olika poängsättningsmetoder. Arbetet omfattar också teoretiska modeller och verktyg för att räkna på konceptets hållfasthet, materialval och val av komponenter. Resultatet av examensarbetet är ett koncept för en formpressningsmaskin som uppfyller de krav som ställts av start up-företaget. Lämpliga delar för grundkonstruktionen av formpressningsmaskinen presenteras. Till dessa hör vad som ska ge upphov till pressfunktionen samt den yttre ramen där de olika komponenterna kommer att sitta. Det resulterande konceptet väger mindre och har mindre dimensioner jämfört med den nuvarande maskinen.
54

Exploring feedstock supply chain for large scale manufacturing of recycled cellulosic textile fiber : A collaborative business model analysis

Rahman, SM Toufiqur January 2022 (has links)
The textile industry is considered one of the most challenging industries when it comes to environmental pollution just after the oil industry. It has a huge impact on water pollution and resource consumption in terms of fiber production. Recently sustainability in cotton fiber production is questioned due to the huge uses of land, water, a large number of pesticides, and a significant amount of energy during cultivation. When it comes to cellulosic pulp production, currently fibrous plant material is used which is mainly wood. So, recycling of cellulosic textiles is considered the only option to reduce this impact. The recycling company Renewcell is launching a large-scale plant for cellulosic fiber recycling which is located in Sweden and will use the post-industrial textile waste as one of its feedstocks. The purpose of this research is to analyze the barriers and drivers for collecting this post-industrial textile waste from the garment manufacturing countries to Sweden and analyze the available collaborative business model alternatives. This study was performed by a qualitative study where primary data was collected through semi-structured interviews and analyzed by thematic analysis. The data was collected among four stakeholders within this value chain which are the fashion brands, recyclers, garment manufacturers, and waste handlers. The finding shows that this sector is very informal and is yet to be formalized. The external informal influence was identified throughout the value chain as a non-value-added activity.  And the involvement of fashion brands was identified as one of the drivers. Several collaborative business models are discussed considering their applicability in different contextual situations. This analysis was discussed based on the seven themes which were generated during the thematic analysis and later discussed with the current empirical study and theoretical background. Collaboration between the recycler, traders, brands, and the textile manufacturers were discussed in different dimensions such as direct collaboration and logistic partnership approach. Then the research limitation was discussed in both methodological and research contexts followed by future research recommendations.
55

The Integration of Biological Growth into Architecture through Biotechnology and Biomimicry

Houette, Thibaut 07 December 2022 (has links)
No description available.
56

Re-Story : The O.T.M.I* project*O.T.M.I = Obsolete Technical Mechanical Item

Kapadia, Ninna January 2015 (has links)
The core question in this master thesis is: What happens to the essence of an object when it becomes out of date and is no longer in use? I am addressing the sense of dignity in once meticulously designed technical/mechanical items that now has become obsolete. The intention has been to investigate how to give new meaning to obsolete items and find new eligibility for their existence.  The investigation was conducted through the development of a method: collection, analysis, deconstruction, investigation and resurrection of a number of O.T.M.I. (Obsolete Technical Mechanical Items).   The resurrection process consisted of the (re-)writing of the objects’ narratives. These stories along with the objects’ parts, spaces and sounds created a frame for a scenography, a soundtrack and characters to act in a film to tell the story. As interior designers we have the opportunity to transform space and fill it with stories. Imagination is an important tool: We benefit from having the ability to imagine, for instance, how different surfaces will reflect sound and light. Our imagination is highly visual. So I have transformed my imaginary world of Obsolete Technical Mechanical Items to visual and audial elements that support the content and values of a story through researching the objects, finding how to clarify and support the story. The Re-Story.

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