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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.
141

Modeling product life cycle networks in SysML with a focus on LCD computer monitors

Culler, Michael 02 July 2010 (has links)
Electronic waste has become a growing concern in the world among governments, businesses, and consumers. These concerns are well founded as electronics waste presents economic, social, and environmental challenges. Economically, discarding electronic waste into landfills represents inefficient use of valuable materials and energy resources. Socially, improperly recycled electronic waste that takes place in third world countries with poor labor standards represents a moral dilemma for developed countries. Environmentally, electronic waste is a threat to all living organisms as it contains proportionally high levels of poisonous and toxic materials. To deal with these growing challenges a strong response needs to be made by all the stakeholders in the life-cycle of electronic devices. However, despite the apparent need, compared to the rapid increases in electronic technology that make it faster, more available, and more affordable, the technology to process electronic waste has not kept pace. This fact alone points to the inadequate funding, attention, and research that has been invested in the problem. Though it also points to an opportunity; the opportunity to build an efficient system to deal with the problem using what is already known about the lifecycle of electronic devices. Therefore, the goal of this work is to create a modeling tool to help stakeholders in the lifecycle of electronic devices understand the consequences of their choices as they affect the use of material and energy resources. To focus the research, LCD computer monitors are chosen as a case study. LCD computer monitors provide a level of sophistication high enough to be interesting in terms of the stakeholders involved, yet simple enough to provide a reasonable scope for this research that is still accessible to the layman As a corollary to this modeling effort, the relatively new systems modeling language SysML and ParaMagic, a program that integrates analysis modeling capability into SysML, will be evaluated. SysML was designed with Model Based Systems Engineering principles in mind thus it seems that it is a natural fit to the problem domain. Furthermore, testing SysML will provide insight into the advantages and disadvantages of the new language. The findings with respect to LCD computer monitors show that increasing the number of end of life options and the amount of monitors flowing into those options could result in substantial network wide material and energy savings. The findings with respect to SysML and ParaMagic are mixed. Although SysML provides tremendous modeling freedom, this freedom can result in increased upfront costs for developing executable models. Similarly, ParaMagic was found to be an effective tool for creating small executable models, but as the size of models increase its effectiveness tends to zero.
142

Selective disassembly for re-use of industrial products

Pornprasitpol, Pornwan, Mechanical & Manufacturing Engineering, Faculty of Engineering, UNSW January 2006 (has links)
As a result of rapid product development, the product life cycle has become shorter, and thus the amount of waste from discarded industrial products has risen dramatically. An awareness of the world???s environmental problems has stimulated researchers to explore the opportunities to reuse, recycle and remanufacture end-of-life products. Disassembly is a systematic approach to separating products into components or subassemblies in order to facilitate recovery of components or materials. However, the full disassembly of a product tends to be unproductive due to technical and cost constraints and product conditions after usage. Therefore, selective disassembly has been introduced as a more practical approach, where only a limited number of disassembly paths that lead to selected parts with recovering potential are considered. This research focuses on the development of a selective disassembly methodology by reversing an assembly sequencing approach. The methodology uses a step-by-step approach to generate a disassembly sequence diagram. This involves listing all the parts within the product, generating a liaison diagram to illustrate part relationships and then establishing precedence rules describing prerequisite actions for each liaison. This is followed by segregating disassembly paths that lead to the removal of selected parts or subassemblies. Then a winnowing process is applied to these paths to eliminate invalid disassembly states and transitions. The last step is to select the optimal disassembly path by using the time requirement as the main selection criterion. In order to shorten the time for carrying out the sequencing process, a javabased program that is capable of performing the first three steps has been created. The program requires three basic inputs in forms of precedence rules, and user-required part (s) and disassembly rules, prescribing which liaison (s) should be done subsequent to a particular liaison. The viability of the methodology and the program is proved through seven case studies conducted on a fishing reel, a single-hole punch, a kettle, an entire washing machine and three washing machine subassemblies. The application of the program allows the users to determine an optimal disassembly sequence in a very short time and with only basic product information as the input.
143

Intégration du risque chimique dans la conception de produits industriels. Application au secteur de l'aéronautique / Integrating chemical risk in industrial products design activities, applied to Aeronautics.

Lemagnen, Maud 20 January 2011 (has links)
Dans un contexte réglementaire contraignant (REACh), ce projet a pour but de développer une méthode permettant d'évaluer, le plus amont possible du processus de conception, le risque chimique potentiellement présenté par un équipement aéronautique depuis sa livraison jusqu'à sa fin de vie. Le résultat s'intègre dans l'ensemble des paramètres gérés par les concepteurs, dans un but d'amélioration de la traçabilité des substances dangereuses et de maîtrise du risque chimique présenté par l'équipement. Le développement de la méthode s'appuie tant sur l'analyse des modes d'évaluation classiques de risques chimiques, pour différents périmètres, que sur celle des pratiques de conception aéronautiques. En parallèle, des tests in situ en Bureaux d'Etudes sont réalisés itérativement, permettant de définir des outils d'évaluation et d'aide à la décision adaptés aux besoins identifiés des concepteurs. Les travaux aboutissent à la proposition d'une méthode permettant au concepteur de répondre à la problématique risque chimique à partir des seules données issues du processus de conception, rendant cette nouvelle approche miscible à ses activités quotidiennes. / In a restrictive context (REACh regulation), this project aims at developping a method enabling one to evaluate, as soon as possible in the design process, the potential chemical risk related to any aeronautic equipment' s part during their different life cycle steps (from delivery to end of life). Assesment results is integrated among the numerous data that are by designers, in order to improve hazardous substances traceability and equipment's chemical risk control. The method's development lays on the analysis of different chemical risk assessments modes (different perimeters) and the understanding of aeronautical design practices. In situ tests (design offices) have been run in an iterative way, in order to define assessment ans decision making tools responding to designers identified needs. The work done leads to the proposal of a method which enables the designer to cope with chemical risk problematics, only from the data resulting from design process : this new approach can be considered as miscible in designer's daily activities.
144

Avaliação de impactos ambientais de equipamentos eletroeletrônicos através de inventário dos materiais usados na fabricação

Valério, Paula Ruhnke [UNESP] 23 July 2014 (has links) (PDF)
Made available in DSpace on 2015-03-03T11:52:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-07-23Bitstream added on 2015-03-03T12:06:27Z : No. of bitstreams: 1 000803503.pdf: 1104411 bytes, checksum: 85ccc688e0d741d11d63b00619c11c11 (MD5) / Os equipamentos eletroeletrônicos fazem parte de uma indústria em expansão na qual a constante inovação torna-se rapidamente obsoletos. O aumento de resíduos eletroeletrônicos incitou várias políticas de descarte e reciclagem, mas ainda faltam estudos qualitativos para que se possa entender quais são os maiores impactos no meio ambiente e o que se fazer para amenizá-los. A pesquisa consistirá na avaliação do desempenho ambiental de dois modelos de impressoras. Será baseada na metodologia de Avaliação de Ciclo da Vida e na posterior simulação de cenários de disposição final. Fez-se uma caracterização de materiais, peças e massas. A impressora A apresentou um impacto 35% maior que a impressora B devido às suas diferenças de composição e funcionalidades. Nos dois casos, o material em maior quantidade e responsável pela maior parcela do impacto calculado foi o HIPS (Poliestireno de Alto Impacto) e a maioria dos impactos pode ser vista na categoria de Combustíveis Fósseis / The electronic equipments are part of a booming industry where constant innovation makes them quickly obsolete equipment. The increase of electronic waste concern generated various disposal and recycling policies but there is still a lak of quantitative studies on the impacts of such products so that they can understand what the major impacts on the environment and what can be done to mitigate the impacts. This research consisted in the characterization of two printers of different models regarding to materials, parts, and weight and using the tool life cycle analyses to quantify the environmental impact of each of them separately and combined. To complete the study a simulation disposal scenarios was made with one of the printers to understand the impacts of recycling, reuse and disposal in a sanitary landfill. The printer. A presented a 35% greater impact than printer B due to their differences in composition and functionality. In both cases the material in greater quantity and responsible for most of the impact was HIPS (High Impact Poltystyrene) and the largest share of the impacts can be seen in the category of fossil fuels
145

Marketing Programmes And Technological Developments Across Product Life Cycle : An Exploratory Study In Indian Machine Building Sector

Mohan, Avvari V 09 1900 (has links) (PDF)
No description available.
146

Integrating Product Model With Assembly Process Model Using Liaisons

Swain, Abinash Kumar 09 1900 (has links) (PDF)
This thesis addresses the problem of achieving better convergence between different phases (here design and manufacturing) of the product development cycle. The use of liaison has been proposed to better integrate the product and assembly process. Two facets of integration have been addressed in this thesis. One is concurrent evolution of the process model with the product model and the second is associativity between product model and process model. A liaison data structure has been proposed, which is set of geometric entities, associated with one or more assembly process that acts as an interface between the product model and process model. As the liaison data is not available explicitly in the product model, a set of algorithms have been developed and implemented to identify and extract the geometric entities defined in the liaison data structure from assembly model. The proposed algorithms can identify and extract liaisons for riveting, welding, bolt fastening, screw fastening, adhesive bonding (gluing) and blind fastening. The developed algorithms have been implemented and tested. The process model needs to evolve with the product model concurrently so that any mistakes or infeasibility in the process model can be flagged right away. The use of liaison enables the construction of process model as the product model is fleshed out. A framework based on liaison has been proposed and implemented to demonstrate the concurrent evolution of product and process model. Linking the changes in the product model to flag the changes (or at least identify the need for changes) in the process model forms the associativity problem. The liaison has been used for maintaining associativity between the product and process model. A framework has been proposed for maintaining associativity between product model and process model that makes use of expert knowledge or tribal knowledge to track impact of changes in product model or process model. An aircraft wing box has been used as an example to illustrate and validate the proposed approaches. Finally the thesis concludes by summarizing contributions of the research and outlining future work.
147

Posouzení environmentální zátěže vybranou technologií tvarování plastů / Environmental Impact Assessment for Chosen Plastic Molding Technology

Dufková, Hana January 2018 (has links)
This diploma thesis deals with assessment of environmental load by selected plastic molding technology. The first part is focused on the ecological legislation in the field of mechanical engineering, which also includes the production of plastics, and describes various methodologies for assessing the environmental load. Another chapter is an overview of polymers and their properties as well as the possibilities of plastics processing with description of individual types of production methods. The practical part of this work describes the composition of the produced piece and the injection molding process of plastic production. Its two methods (direct gating and hot sprue method) are analyzed and then the environmental load evaluation is performed using the LCA method – product life cycle assessment. The environmental load of both production methods is assessed.
148

Visual Computing als Basis für Prozessinnovation im Produktlebenszyklus

Freiherr von Lukas, Uwe 25 September 2017 (has links)
Aus der Einführung: "Die Informationstechnik ist seit den Anfängen von CAD vor ca. 50 Jahren ein wesentlicher Impulsgeber für die Produktentwicklung und hat maßgeblichen Anteil an Prozessinnovationen wie dem Global Engineering oder der Digitalen Fabrik. Längst geht es aber heute nicht mehr allein um die Geometriebeschreibung zukünftiger Produkte, sondern um die möglichst umfassende Begleitung und Ergänzung des realen Produkts durch das virtuelle Produkt: von der ersten Idee bis zum Recycling. Die umfassende Vision des virtuellen Produkts als Pendant zum realen Produkt (Spur & Krause 1997) ist untrennbar mit dem Fortschritt der Informationstechnologie verbunden."
149

RMS capacity utilisation: product family and supply chain

Abdi, M. Reza, Labib, A.W. 09 June 2016 (has links)
Yes / The paper contributes to development of RMS through linkage with external stakeholders such as customers and suppliers of parts/raw materials to handle demand fluctuations that necessitate information sharing across the supply chain tiers. RMS is developed as an integrated supply chain hub for adjusting production capacity using a hybrid methodology of decision trees and Markov analysis. The proposed Markov Chain model contributes to evaluate and monitor system reconfigurations required due to changes of product families with consideration of the product life cycles. The simulation findings indicate that system productivity and financial performance in terms of the profit contribution of product-process allocation will vary over configuration stages. The capacity of an RMS with limited product families and/or limited model variants becomes gradually inoperative whilst approaching upcoming configuration stages due to the end of product life cycles. As a result, reconfiguration preparation is suggested quite before ending life cycle of an existing product in process, for switching from a product family to a new/another product family in the production range, subject to its present demand. The proposed model is illustrated through a simplified case study with given product families and transition probabilities.
150

The management of electronic waste : a case study of the Umbogintwini Industrial Complex and Southgate Business Park in KwaZulu-Natal, South Africa

Govender, Krishna January 2016 (has links)
Submitted in fulfillment of the requirements for the degree of Master Of Technology In Business Administration, Department of Entrepreneurial Studies & Management, Durban University of Technology, Durban, South Africa, 2016. / The phenomenal growth in the number of electronic devices in use has given rise to a huge increase in the volume of electronic waste (e-waste) generated. Electronic waste is comprised of toxic materials and chemicals, and if it is not disposed of in an environmentally friendly manner, it poses serious risk to the environment and to human health. The perceived limited knowledge about the harmful effects of e-waste and the potential economic benefit of e-waste recycling in South Africa motivated this study. The study area consisted of two large industrial parks in Durban, KwaZulu-Natal; namely, the Umbogintwini Industrial Complex and the adjacent Southgate Business Park. A total of 313 organisations are located within the study area, which is spread over approximately 550 hectares. Based on the findings of the study, it is estimated that the Umbogintwini Industrial Complex and the Southgate Business Park would generate approximately 593 tons of e-waste between the period 2015 and 2020, averaging approximately 119 tons per year. Although South Africa is classified as a developing country, it is the most developed country in Africa, and if one were to extrapolate the potential volume of e-waste generated for five years from the study area to the rest of KwaZulu-Natal’s industrial parks, then in five years, the province’s industrial parks would generate approximately 3 340 tons of e-waste. The study also revealed that there is no effective e-waste management strategy in place within the Umbogintwini Industrial Complex or the Southgate Business Park. A positive finding of the study was that the majority of the organisations surveyed were in favour of a proper e-waste management strategy at both the study sites, and would support the development of an e-waste recycling plant in this industrial zone. / M

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