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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.
1

Exploring challenges in a verification process - when adapting production processes to new environmental requirements

Ahvenlampi Svensson, Amanda January 2016 (has links)
The requirements on the products and production processes within the manufacturing industry are continuously increasing according to environmental standards. The new requirements are coming from a growing awareness of what our planet can provide for example by the global challenge of climate change. The industry needs to reduce energy consumption and waste to meet the upcoming requirements. One of the processes with high environmental impact in a discrete manufacturing industry is the paint shop. Surface treatment is also of great importance to maintain a high quality product. In scientific literature, technological risk is one of the barriers in implementing environmental conscious manufacturing. Therefore the area of sustainable operations management needs building bridges with other functions and disciplines such as economics, strategies and behavioral sciences in order to manage the transitions. The supply of competence around paint shops today is usually provided by suppliers and other sources within the industry and to make the collaboration to work is essential. In this process of collaboration with external sources, substantial measurements are required to maintain the desirable quality. In order to ensure the competence of testing the quality eventuate when switching technology at a pre-treatment line, this report sets out to explore what the challenges to be taken into consideration are when to assure the product- and- process quality. To respond to this question, a multiple case study is conducted during spring 2016 where the phenomenon to study is the change process and the unit of analysis is the challenges that can be faced during the verification process. The case studied is automotive companies located in Sweden which are producing components for heavy duty vehicles. Data collection is performed by studying documents, participatory observations and semi-structured interviews. The results will give insights to academia on what challenges that are occurring during the verification process of implementing new and cleaner technologies. The conclusions are drawn upon the literature and the empirical results. The managerial implications are to increase the awareness of any potential barriers in the verification process in order to be prepared for managing the technological change process.
2

Grown furniture : a move towards design for sustainability

Cattle, Christopher January 2002 (has links)
This thesis deals with the proposal that environmentally benign items of free standing furniture may be produced by the use of such well established techniques as training and grafting natural tree growth to shape. The project has been driven by the growing environmental concerns of which mankind has become aware in the late twentieth century, and which are starting to exert such a powerful influence in the twenty first. A broad history of man's use and control of natural tree growth, ranging geographically from Europe to Australia, and in size from hand held agricultural picks to eighteenth century sailing ships, is followed by a brief description of the ways in which the explosive increase in world popuanon. together with the expanding industrial activities of the Western consumer society, are feared to be threatening the stability of the natural environment. The various disasters and catastrophic accidents which have brought this situation to the attention of the general public are briefly surveyed, together with National, International and a range of Industrial responses. As one of the professions most closely concerned with the production of consumer items, the various reactions of the Design Community are similarly examined. In conclusion, the author's proposal for an experimental item of furnitureenvironmentally benign in production, use and disposal - is described and illustrated. A simple free standing three legged stool, the form of both the item itself and that of the jig required to control it's growth, are described and illustrated. The growth of examples of this, carried out on three sites across southern Britain are documented, experimental results reported and discussed. A further range of designs suitable to be produced using this method of controlling and grafting natural growth is proposed, and suggestions made for further experimentation.
3

Development of collaborative green lean production systems

Kurdve, Martin January 2014 (has links)
This thesis deals with development of lean and green production systems from an action research point of view. The studies focus on Swedish-based automotive and vehicle industries and their aims to integrate sustainable thinking and environmental care into their operations management. Starting from operations management in manufacturing and corporate sustainable development, the research is built on how to integrate these two views into one production system. The systematic structure of a multiple-target improvement process with methodologies and tools designed to achieve the sustainability vision has been studied. Since lean as well as green production is based on the entire value chain, the research has gone beyond legal company limits and included the collaborative efforts between suppliers and customers in the value chain. The thesis includes six papers and describes approaches on how to implement integration, how to structure and integrate improvement management systems, how to set up an integrated monitoring and control system for the business and how to organise and redesign green lean tools and methodologies to support collaboration towards common targets. The results can be used for exploration and hypothesis formulation for further studies and development of integrated production systems and collaboration systems. The thesis helps answering how to integrate and implement company-specific green lean production systems.
4

Sustainability in global production networks : rethinking buyer-driven governance

Alexander, Rachel Ruth January 2016 (has links)
Achieving sustainable production is a critical task in today’s globalised world. This is especially the case in the cotton garment industry where globally dispersed suppliers feed rapidly expanding demand across international markets. Practices associated with cotton garment production face numerous sustainability challenges from cotton farming to textile and garment manufacturing. Retailers are under increasing pressure to address these challenges and leading retailers are now actively trying to promote more sustainable production across all stages of production from raw material to final product. While numerous studies have investigated the relationship between retailers and their upper tier suppliers, there is little understanding of how sustainability challenges can be addressed across fragmented production processes. It is this gap that this thesis seeks to fill. Promoting sustainable production from raw materials to the final stages of manufacturing involves influencing practices of a diverse set of businesses responsible for different stages of production. This thesis defines the set of businesses that turn raw materials into final products as an ‘extended supplier network’ (ESN). Drawing on global value chain (GVC) and global production network (GPN) approaches to understanding how production is organised, the core question of this thesis is: To what extent is buyerdriven governance sufficient for promoting sustainable production across fragmented production processes in an ESN? GVC and GPN research provides insight into this issue as it offers a way to conceptualise how lead firms influence their suppliers. The GVC approach highlights the importance of lead buyers. The GPN approach incorporates this argument but further emphasises the importance of spatiality and the roles of a wider set of actors and processes. While both approaches theoretically incorporate all stages of production, garment industry studies using these approaches have tended to focus on relationships between brands and retailers and upper tier suppliers, paying insufficient attention to lower tiers. Considering the case of Indian cotton clothing production for major UK retailers, this study explores retailers’ governance relationships with producers at different points in their ESNs. Producers’ experiences of vertical governance through buyer-seller relationships across all stages of production within an ESN are explored. These producers’ experiences with horizontal governance within distinct local productive systems are also considered. Diverse producers’ locations within the ESN and within local productive systems are found to involve different governance experiences within the same ESN. Across the ESN, vertical governance flows are found to be limited by variation in potential for buyer governance across buyer-seller relationships in the multiple vertical pathways connecting retailers to raw material producers. Alternatively, retailers can connect to producers by making non-sourcing horizontal connections with actors in local productive systems. While dominant methods in retailers’ efforts at governance for sustainability have been vertical, horizontal connections are increasing across the industry. However, despite the emergence of new connections, this research finds that retailers’ influence over lower tier production processes remains limited. Empirically, this thesis provides insight into the complexity of sustainability challenges involved in the production of cotton garments. Conceptually, it shows the nature of diverse governance relationships across an ESN. It also emphasises that effective governance for sustainability cannot be achieved simply through vertical buyerdriven governance. Instead a more nuanced, and more complex, understanding of the interplay between vertical and horizontal is required, particularly considering the role of alliances. This has significant implications for policy, including the public and private governance for sustainability in the global cotton garment industry.
5

Sustainable Production of Novel Biomaterials in Escherichia coli

Rahman, Asif 01 May 2014 (has links)
The biotechnology revenues in the United States exceeded $100 billion in 2010 and the potential impact of synthetic biological engineering has been identified nationally as an emerging technology to further expand the national bioeconomy. Synthetic biological engineering approaches biology from an engineering perspective to make biology easier to engineer. The potential to engineer microorganisms for novel applications can have far-reaching implications and benefits for society. Some of the potential applications range from biosensors, biofuels, therapeutics, and biomaterials. In this study two biomaterials were produced in genetically engineered Escherichia coli: polyhydroxybutyrates (PHBs) and spider silk. PHBs are bioplastics that have similar properties to petrochemical-derived plastics. Synthetic biological engineering can be used to optimize PHB extraction from E. coli by secretion of the PHB polymer outside of the cell. Another biomaterial, spider silk, was also produced in E. coli. Spider silk is a unique material with high tensile strength and elasticity and thus could have a wide range of potential applications. Since spider silk is not naturally produced in microorganisms, the DNA sequences were optimized for increased production in E. coli. In addition to optimization of bioproduct production in microorganisms using synthetic biology, another major cost is the carbon substrate. In this study wastewater microalgae were used as an alternative carbon substrate. Coupling synthetic biological engineering and sustainable engineering could potentially make production of bioproducts economically viable in the future.
6

Kvalitet vazduha pod pritiskom u funkciji održive proizvodnje / Compressed air quality as a function of sustainable production

Milenković Ivana 10 October 2014 (has links)
<p>U radu se proučava kvalitet vazduha pod pritiskom iz aspekta održive proizvodnje. Zahtevani kvalitet vazduha postiže se primenom filtera<br />i sušača. Filteri vazduha izazivaju pad pritiska, koji ako se smanji,<br />smanjuje se i ukupna količina proizvedenog vazduha pod pritiskom, čime<br />se povećava energetska efikasnost. Utvrđuje se povezanost primene<br />različitih filtera i pada pritiska, uz poštovanje kvaliteta vazduha.<br />Osim toga, analiziran je kondenzat, koji se pri filtraciji javlja u<br />sistemu, i kreirane su odgovarajuće preporuke za njegovo odlaganje, jer<br />se on svrstava u opasan otpad zbog prisustva ulja.</p> / <p>This paper examines the quality of compressed air from the aspect of<br />sustainable production. The required air quality is achieved by using filters<br />and dryers. Air filters generate the pressure drop, which, if reduced, reduces<br />the total volume of produced compressed air, which lead to increase in<br />energy efficiency. Connections between the application of different filters and<br />pressure drops with respect to quality are explored. In addition, the<br />condensate from the compressed air system is analysed, and appropriate<br />recommendations for its disposal are created because it is classified as<br />hazardous waste due to the presence of oil.</p>
7

Viabilidade econômica de um sistema de produção pecuária de bovinos sob alta lotação: uso na pesquisa e na pecuária comercial / Economic viability of a cattle system production under high stocking rate: use in research and commercial livestock

Rodrigues, Rinaldo 26 November 2010 (has links)
Um estudo de viabilidade foi desenvolvido com o objetivo de verificar a economicidade de um sistema de produção de ciclo completo de pecuária de bovinos de corte, sob alta lotação. O sistema foi inicialmente concebido para a utilização em pesquisas na Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo, sendo que esta dissertação buscou avaliar a viabilidade econômica de tal sistema quando aplicado à pecuária comercial. Para tanto foram utilizados dez cenários, nove dos quais definidos a partir da variação de preços dos produtos vendidos, utilização de capital próprio e recursos de financiamento rural via programa do Banco Nacional de Desenvolvimento Econômico e Social (BNDES). O décimo cenário utilizado foi definido a partir de um nível pré-determinado de preço dos produtos vendidos e utilização de capital próprio, decorrente de arrendamento de área liberada a partir da intensificação do sistema de produção. O método de análise econômica utilizado foi o de Fluxo de Caixa e as técnicas aplicadas foram: Payback Simples, Payback Descontado, Valor Presente Líquido (VPL) e Taxa Interna de Retorno (TIR). O sistema mostrou-se economicamente viável estritamente para os cenários que consideraram o nível máximo de projeção de preços da arroba da carne e para o cenário que considerou o arrendamento de área liberada a partir da intensificação do sistema de produção. A utilização de financiamento via Programa de Crédito Rural do BNDES proporcionou melhora expressiva nos valores monetários e índices utilizados na análise. / A study was carried out to verify the economic viability of a life-cycle production system of beef cattle under high stocking. This system was initially designed for use in research at the school of Veterinary Medicine and Animal Science, Universidade São Paulo, but this dissertation tried to evaluate the economic viability of this system when applied to commercial livestock. Therefore, ten scenarios were studied. Nine of them were determined by the variation of prices of products, use of own capital and resources from rural finance programs from Banco Nacional de Desenvolvimento Ecônomico e Social (BNDES). The tenth scenario was based on a predetermined level of prices of products and use of own capital, due to leasing of the area released from the intensification of the production system. The analysis method was the Cash Flow and the applied techniques were: Simple Payback, Discounted Payback, Net Present Value (NPV) and Internal Rate of Return (IRR). The system showed to be economically viable for the scenarios that considered the maximum projection of meat prices and for the scenario that considered the leasing area related to the intensification of the production system. Funding from BNDES Rural Credit Program has provided significant improvement in the monetary values and indices used in the analysis.
8

Strategies to Obtain Certification for Cocoa Bean Production

Opoku, Emmanuel Adem 01 January 2019 (has links)
Leading cocoa-consuming countries have declared that in the year 2020, they will permit imports of sustainably sourced cocoa beans only, threatening the sustainability of the cocoa farming business. Certification offers enhanced market access for sustainability of the business of cocoa bean producers in Ghana. The purpose of this case study was to explore the strategies that farm managers used to obtain certification for cocoa bean production. Seven farm managers of a cocoa producer's cooperative located in the eastern region of Ghana who consistently produced certified cocoa beans for at least 5 years participated in the study. Deming's quality management theory served as the conceptual framework for this study. Semistructured interviews constituted the primary technique for data collection. Additional data from UTZ-certified documents and the archives of the cooperative supported the process of achieving data saturation. Data were analyzed using Bengtsson's manifest content analysis framework of decontextualization, recontextualization, categorization, and compilation to arrive at conclusions. Three themes emerged from data analysis: training in farming practices and certification code of conduct, management discipline, and environmental and social sustainability. The implications of this study for social change include the potential that certification might influence a positive change in the farming practices of Ghanaian cocoa farm managers. Social change might be reflected in the adoption of sustainable production practices, improved living conditions of producers, and biodiversity conservation.
9

Biomimicry For Sustainability: An Educational Project In Sustainable Product Design

Bakirlioglu, Yekta 01 September 2012 (has links) (PDF)
The notion of sustainability has become an extensive area of research ever since the term emerged in the late 1980s, due to the negative effects of unsustainable production and consumption patterns on environmental stewardship, social equity and economic development. There have been various approaches developed for product design and education within the context sustainability. Biomimicry is one of those approaches, and its implications for product design education have recently started to be explored. In this study, an educational tool - Biomimicry Sketch Analysis (BSA) - was developed and integrated into the idea-generation phase of an educational design project at the undergraduate level in the Department of Industrial Design at the Middle East Technical University (METU). This integration is analyzed throughout the graduate thesis study, to understand and explore the implications of the biomimicry approach for sustainability in product design education. The educational tool within this approach was found as influential among the third year industrial design students for the idea-generation phase, yet the results of this study included both pros and cons for the incorporation of the BSA exercise.
10

Making high-value, long-lived isotopes to balance a sustainable radiotracer production facility

Engle, J. W., Barnhart, T. E., Valdovinos, H. F., Graves, S., Ellison, P. A., Nickles, R. J. 19 May 2015 (has links) (PDF)
Introduction The embrace of PET by medical clinicians has been reluctant (ΔT ≈ 20 yr) primarily due to the scale of the infrastructure that is needed. The capital cost of a cyclotron (≈ 106 USD) is now dwarfed by the demand for compliance to recent regulatory standards. This is a recurring expense, not only imposing an order-of-magnitude increase in staffing and operating costs, but damping the enthusiasm of researchers recalling the brisk pace of research in earlier days. Now an academic site, with little interest or opportunity to scale up production for wider distribution, is burdened by the new regulatory terrain of good manufacturing practice (GMP), mandated for translational studies that will reach only a few subjects. With our production resources held within a basic science department, the Medical Physics cyclotron facility at the University of Wisconsin has sought a sustainable pathway. We now anchor the operating budget by providing high-value, long-lived radionuclides to off-site users, to buffer the fluctuations of local demand for conventional PET synthons. Material and Methods: The tools of the trade The radioisotopes discussed here belong to the 3-d and 4-d sub shell, but are now moving into the rare-earths, with applications ranging from - targeted molecular imaging agents, - internal radionuclide therapy using to Auger electron-emitters, - to basic physics experiments using 163Ho (t1/2 ≈ 4500 yr) to determine the mass of the neutrino. Rather than focusing on the dozens of radionuclides produced, a number of tools deserve mention, as they support a variety of targets, reactions and products. These will be listed in order (A-G) from cyclotron to extraction to analysis. A. Two cyclotrons are used, a legacy RDS 112 (#1; 1985) and a GE PETtrace (2009). Neutron and gamma detectors are monitored during the long irradia-tions, signaling any subtle changes in the running conditions. (1). The PET-trace is fitted with a quick-change variable degrader target (2), as well as a beam-line with a 5-port (0 o, ±15 o, ±30 o) vertical switching magnet (3). The downward directed beam ports provide support for solid targets (e.g. Ga, S, Se, Te) that melt at low temperature. The irradiation of gas targets employs a generalized manifold to handle inert gases such as 36Ar for the production of 34mCl, as well as natural Kr and Xe for making Rb and Cs isotopes to act as fission product surrogates. These products are captured on a stainless steel target chamber liner, and rinsed off with warm water. The alkali metals are convenient tracers to study the ion exchange trapping process, pivotal in future 99Mo production from solution reactors (4). B. The preparation of malleable solid targets employs a 10-ton hydraulic bench press, and a jeweler’s mill to roll out foils from pellets, pressed between Nb foils to avoid contamination. C. Binary alloys are smelted in a programmable 1600o tube furnace under argon flow (eg. NiGa4). Alternatively, an induction furnace now permits highly localized heating of the binary metal charge, while allowing mechanical agitation during the smelting process. D. Electroplating onto gold discs is used for various enriched target material or the alloys above where quantitative recovery is essential, or where heat transfer from high beam current is demanding. E. The separation chemistry, prior to che-lation to targeted molecular imaging agents, is performed in LabView-driven, home-built “black boxes” resident in mini-cells (Radiation Shielding Inc.). F. Analysis of the targets after irradiation makes use of HPGe spectroscopy for gammas and characteristic X-rays of decay (e.g. rare earths). The elemental constitution of target alloys is deter-mined prior to irradiation by X-ray fluorescence analysis, excited by 109Cd and 241Am sources. G. Finally, broad-band elemental analysis at the ppb level now makes use of a microwave plasma atomic emission spectrometer (Agilent 4200), to be de-scribed elsewhere in this meeting. Results and Conclusions The tools above (A-G) are employed in the pro-duction of the expanded list of radionuclides offered by our cyclotron group to both local and off-site colleagues. The list below is ordered in terms of decreasing use, from regular production for national distribution (64Cu, 89Zr), to weekly inhouse use (44Sc, 66,68Ga, 68,69,71Ge, 72As, 61Cu, 86Y), to infrequent production for multi-site collaborations (163Ho, 95mTc, 206Bi): Radionuclide Target Employs 64Cu 64Ni/Au A, D, G 89Zr natY A, E, G 44Sc natCa A, B, E, F, G 66, 68Ga Zn/Ag A, B, D, E, F, G 68, 69, 71Ge Ga, GaO2 A, B, C, E,F 72As GeO2 A, B, E, F 52Mn natCr A, E, F, G 76, 81mBr SeO A, E, F 34mCl, Rb, Cs noble gas A, E, F 95mTc,163Ho Mo, Dy A, E, F TABLE 1. Target materials and processes. The production of long-lived radionuclides lends itself to crowd-sourcing, with distributed irradia-tion at virtually any site with a suitable accelera-tor and a relaxed beam schedule. A number of unique challenges do arise that don’t appear in the usual production of conventional cyclotron products such as 11C or 18F. Contamination by stable metals, inadvertently introduced by target pressing or beam-induced sputtering from degraders, can cause serious interference downstream limiting effective specific activity. Long-lived manganese isotopes are ubiquitous. And some very high value products are simply not within the reach of small cyclotrons, such as 52Fe and 67Cu, being too far off the line of beta stability. In conclusion, the research leading to a doctoral degree necessarily must focus on the physics and chemistry of novel radionuclides and tracers. On the other hand, clinical and translational research needs established imaging agents, with little room for innovation within the regulatory constraints. Our experience at Wisconsin has led us to a balancing act, with our routine production of clinical doses countered with our research program to provide high-value radionu-clides for our collaborative work with our basic science colleagues.

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