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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

Visualization of Environmental Waste by Manufacturing : Equip VSM with Green Perspective

Hu, Juebin, Lu, Shan January 2011 (has links)
This thesis is a subtask of the research project “Green Production System”, which is jointly launched and run by Volvo/Volvo Technology, Haldex, Saab and All-Emballage J.E. AB as industrial party, and Mälardalen University as academic party. The whole project is dedicated to develop “green production system” to be a competitive mean to Swedish automotive and manufacturing industry through four work packages, which are “Wet preconditions and frames of a green production system”, “Visualization of environmental impact and added value”, “Development and implementation of tools for green control and management” and “Development of guidelines for environmental value improvement and cost decrease” respectively. And this thesis is an effort to package 2. Value stream mapping is assumed to be a potentially effective tool to be developed for visualizing environmental wastes produced by production processes. Thereby, the focus of this thesis is on the transformation of VSM into EVSM (Environmental Value Stream Mapping). By reviewing literature, the reduction of environmental wastes is additionally counted into a characteristic of lean production. Meanwhile, seven environmental wastes are identified and defined. The development of EVSM is on an absolutely great degree based on the identification and measurement of environmental wastes. Thus, waste measurement and production data collection are supposed to be the prerequisite of EVSM implementation. In order to verify the supposition, a test practice was carried out in CH Industry AB, which is a metal processor. After the practical study, CH’s incompetence of working on EVSM is analysed, and advice is proposed. At the end of thesis, analysis of EVSM is made in terms of its prerequisite, difference from VSM, pros and cons, etc. In addition, suggestions for further research are given.
2

Green Manufacturing of Lignocellulosic Fiber through Bacterial Degradation Process

Fu, Yu 12 1900 (has links)
Lignocellulose is the most abundant biopolymer on earth and offers excellent potential for sustainable manufacturing. Because lignocellulose is structurally complex and resistant to decomposition, innovative degradation strategies are necessary to unlock its value. In this dissertation, a green manufacturing process through enzyme-triggered self-cultured bacteria retting for lignocellulosic fiber was developed and investigated. The mechanism of the lignocellulosic fiber retting at a controlled degradation strategy was studied. This enzymatic degradation strategy utilizes a small amount of enzyme to trigger a large aggregation of specific bacteria to obtain clean fibers. Industrial hemp (Cannabis sativa L.) fiber was successfully retted with this strategy. The degradation of pectin was proved through an environmental scanning electron microscope and reducing sugar analysis. The bacterial successions were identified by 16S rRNA gene metagenomic sequencing. The results showed that Bacillaceae dominated the hemp retting conditions containing 1% pectinase, suggesting that pectinase can manipulate bacterial community succession by changing the nutrients available to bacteria through the degradation of pectin. This degradation strategy has 20-25% less environmental impact than the thermochemical degradation strategy, resulting in better fiber consistency and much shorter processing time (3-5 days) than the traditional water degradation strategy. The study on the degradation of lignin-rich lignocellulose also contributes to the understanding of the natural formaldehyde release mechanisms from wood.
3

Green Manufacturing and Direct Recycling of Lithium-Ion Batteries

Lu, Yingqi 03 September 2020 (has links)
According to the International Energy Agency, the global Electric Vehicle (EV) sales are experiencing approximately 24% annual growth and the total market could reach 4 million in 2020 and 21.5 million by 2030. However, the mass production of lithium-ion batteries (LIBs) to power EV creates concerns over environmental impacts and the long-term sustainability of critical elements for producing the major battery components. Although much investment has been made, it is still imperative to develop an effective LIB production and recycling process. This dissertation demonstrates a green and sustainable paradigm for LIBs where the batteries are manufactured and direct recycled to form a closed loop. The water-based cathode electrode delivers comparable cycle life and rate performance to the ones from the conventional organic solvent-based process. The direct recycling process has the advantages to regenerate the cathode material from electrode instead of decomposing into elements. Utilization of a water-soluble binder enables separating the cathode compound from spent electrodes using water, which is then successfully regenerated to deliver comparable electrochemical performance to the pristine one. When scaled up, the degraded cathode material can be directly regenerated by an optimized relithiation thermal synthesis (RTS) method to resynthesize the homogeneous cathode powder of high quality. The key factors and sintering procedures are studied to ensure the performance of the product. The pilot scale test successfully scales up to Kg-level with recycled output materials delivering good electrochemical performance. To automate the direct recycling process and improve the efficiency, machine learning and sensors are utilized in a novel battery disassembly platform. It can classify different batteries based on their types and sizes. The processing temperature is instantly monitored using thermal imager, and the prediction model is trained to give the prediction for measures taken by a closed loop control system. Furthermore, the image recognition is employed for quality control after the cutting process and the defect can be mitigated to ensure effective dismantling of End-of-life (EOL) batteries. The integration of machine learning techniques makes the elaborate dismantling process safer and more efficient. / Doctor of Philosophy / According to the International Energy Agency, the global Electric Vehicle (EV) sales are experiencing approximately 24% annual growth and the total market could reach 4 million in 2020 and 21.5 million by 2030. However, the mass production of lithium-ion batteries (LIBs) to power EV creates concerns over environmental impacts and the long-term sustainability of critical elements for producing the major battery components. In this work, a green and sustainable manufacturing and recycling paradigm for LIBs is ushered and scaled up to pilot-scale test. Compared with the electrodes produced by conventional organic solvent-based process, the water-based electrodes can deliver comparable battery performance, meanwhile reduce the cost as well as the pollution to environment. The spent batteries are successfully regenerated to form the closed loop system with minimal external toxic solvent used. At pilot-scale, Kg-level battery material can be directly regenerated to deliver high-quality cathode powder. It provides the guidance of design parameters for large-scale battery recycling in industry. To automate the direct recycling process and improve the efficiency, machine learning and sensors are utilized in a novel battery disassembly platform. The integration of machine learning techniques makes the elaborate dismantling process safer and more efficient.
4

An integrated decision support framework for the adoption of lean, agile and green practices in product life cycle stages

Udokporo, Chinonso Kenneth January 2017 (has links)
In order to stay competitive in today’s overly competitive market place, businesses must be engineered to match product characteristics and customer requirements. This increased emphasis on achieving highly adaptive manufacturing with reduction in manufacturing costs, better utilization of manufacturing resources and sound environmental management practices force organisations to adopt efficient management practices in their manufacturing operations. Some of the established practices in this context belong to the Lean, Agility and Green (LAG) paradigms. Adopting these practices in order to address customer requirements may require some level of expertise and understanding of the contribution (or lack of it) of the practices in meeting those requirements. Primarily, the wide choice of LAG practices available to address customer requirements can be confusing and/or challenging for those with limited knowledge of LAG practices and their efficacy. There is currently no systematic methodology available for selecting appropriate LAG practices considering of the product life cycle (PLC). Therefore, this research provides a novel framework for selecting appropriate LAG practices based on PLC stages for reducing costs, lead time and generated waste. The methodology describes the application of analytic hierarchy process (AHP), statistical inference and regression analysis as decision support tools, ensuring a systematic approach to the analysis with appropriate performance measures. The data collected were analysed with the aid of SPSS and Excel using a variety of statistical methods. The framework was verified through a Delphi study and validated using a case study. The key findings of the research include the various contributions of lean, agile and green practices towards improving performance measures, the importance of green in improving performance measures and the importance of selecting appropriate practices based on product life cycle stages. This research makes a clear contribution to existing body of knowledge by providing a methodological framework which could serve as a guide for companies in the FMCG industry to systematically integrate and adopt lean, agile and green to better manage their processes and meet customer requirements in their organisations. However, the framework developed in this research has not been tested in other areas.
5

Implementation of Green and Lean manufacturing in post processing activities : A qualitative case study at a barrier coating facility

Tagesson, Daniel, Karlsson, Isak January 2021 (has links)
To reach the sustainable development goals of agenda 2030, mankind must continuously work towards developing sustainable industrial processes. The concept of Total Quality Management, Lean/Green manufacturing has been frequently applied separately, but studies indicate that the combination of the concepts can yield synergically benefits from an economic and environmental perspective. The process industry has a continuous flow of residuals which is a potential opportunity to gain a competitive edge through eliminating waste and embracing a circular economy system. The lack of exploring operational methods to achieve better results in relation to waste management and utilization of waste have inspired this thesis. This study has established a chain of events that enable other researchers and managers to find, define, explain and solve problems connected to waste management systems. The results indicate that it is possible to find opportunities within the organization to reuse already procured resources but also that the utility of storage vessels is connected to the overall efficiency of the waste management system. Interestingly, the results also indicate that there is an industrial culture related to the case that hampers the increase of efficiency which can be explained by the cornerstones of Total Quality Management and Lean manufacturing. Lean waste i.e., unused creativity thrives and hampers new ways to decrease cost and lower environmental impact when employees are not encouraged to communicate or innovate. Monetary gains and environmental savings is achievable by measuring, including and involving personal combined with a dedicated management. / <p>En väl genomförd och beskriven studie där studenterna lyckas ge bidrag av både praktisk naturoch teoretisk.</p>
6

Enhancing Protein and Enzyme Stability Through Rationally Engineered Site-Specific Immobilization Utilizing Non-Canonical Amino Acids

Wu, Jeffrey Chun 01 December 2014 (has links) (PDF)
The demand for economical, efficient protein production, reuse, and recovery has never been greater due to their versatility in a large variety of applications ranging from industrial chemical manufacturing to pharmaceutical drug production. The applications for naturally and artificially produced proteins include protein drugs and other pharmaceutical products, as biocatalysts in environmentally friendly chemical manufacturing, as enzymes for food processing purposes, and as an essential component in many biomedical devices. However, protein production suffers from many challenges, which include the cost of production, protein stability especially under harsh conditions, and recoverability and reusability of the proteins. The combination of two developing technologies, cell-free protein synthesis systems (CFPS) and unnatural amino acid incorporation, provides solutions to these protein production challenges.This dissertation reports on the use of cell-free protein synthesis systems and unnatural amino acid incorporation to develop new proteins and enzyme immobilization techniques that significantly increase activity and stability while simplifying recoverability and reuse.
7

Determinantes estratégicos de ecoeficiências de empresas chinesas no Brasil / Strategic ecoefficiency determinants of Chinese companies in Brazil

Lennan, Maria Laura Ferranty Mac 23 November 2016 (has links)
Preocupações com sustentabilidade ambiental são recorrentes tanto no meio acadêmico, como no meio empresarial. Elas ecoam ao se pensar no crescimento econômico chinês e nos impactos das atividades produtivas no meio ambiente. A China é o país emergente com as maiores taxas de crescimento econômico no mundo, porém sua imagem também reflete sua vulnerabilidade com relação à ecologia. Tendo isso em consideração e procurando compreender como isso repercute nas operações internacionais, esta tese estuda os determinantes estratégicos das empresas chinesas em operação no Brasil, pelas lentes teóricas do tripé da estratégia. A sustentabilidade ambiental se operacionalizou em ecoeficiência, termo desdobrado em eco-inovação, eco-reputação e manufatura verde. Dado que os aspectos estratégicos direcionam as ações empresariais, isto se torna ainda mais complexo ao se analisar a operação internacional, uma vez que além dos aspectos internos e de mercado, a empresa é influenciada por forças institucionais relacionados com seu mercado de origem e com o mercado de destino das vendas externas. Esta tese inova ao relacionar aspectos do tripé da estratégia com as estratégias de ecoeficiência de empresas chinesas no Brasil. São utilizadas técnicas quantitativas para testar as hipóteses. A análise é feita utilizando modelo de equações estruturais, com o software SmartPLS v3. Os resultados indicam que há associação positiva entre os recursos internos da empresa e ações de ecoeficiência nos seus três desdobramentos (eco-inovação, eco-reputação e manufatura verde). No caso da visão baseada na indústria, encontrou-se associação positiva com manufatura verde e eco-reputação, mas não com as iniciativas de eco-inovação. Os aspectos institucionais do mercado brasileiro não puderam ser associados com nenhuma das iniciativas de ecoeficiência. Esta tese contribui para o entendimento de determinantes estratégicos na adoção de iniciativas ambientais, ao indicar a importância dos recursos na implantação dessas estratégias. Não se confirma a importância da vertente institucional no modelo teórico-conceitual, o que mostra limitação à extensão dessa teoria. Os resultados, do ponto de vista gerencial, mostram que as forças de mercado estimulam as empresas a empreender em iniciativas de eco-reputação e os processos de manufatura. Contudo, verifica-se que os aspectos de eco-inovação nas empresas chinesas ainda não foram influenciados pelas demandas do mercado brasileiro. / Concerns about environmental sustainability are recurrent both in academy and in business. This concern echoes especially because of the impact of Chinese productive activities on the environment. China is an emerging country with the highest economic growth rates in the world, but its image also reflects their vulnerability on ecological issues. Taking this into consideration, this thesis studies the strategic determinants of Chinese companies operating in Brazil by the theoretical lenses of strategic tripod. Environmental sustainability is operationalized into eco-efficiency, a term translated into eco-innovation, eco-reputation and green manufacturing. To the extent that strategy directs business actions, it becomes even more complex when analyzing the international operation, as well as internal aspects and market, the company is influenced by institutional forces from home market and the target market of foreign sales. This thesis contributes to relate aspects of the strategy tripod with the eco-efficiency strategies of Chinese companies in Brazil. This thesis contributes to relate the strategy tripod with the eco-efficiency strategies of Chinese companies. To this end, methodology was quantitative, with data collected and examined in order to confirm or refute the hypothesis. They were analyzed by structural equation model, with SmartPLS v3 software. The results indicate that there is a positive association between the internal resources and eco-efficiency in its three developments (eco-innovation, eco-green reputation and manufacturing). About the industry-based view, there is a positive association with green manufacturing and eco-reputation, but not with eco-innovation initiatives. Brazilian institutional aspects could not be associated with any of the eco-efficiency strategies. To literature, this thesis contributes to the understanding of strategic determinants on adopting environmental initiatives. It highlights the importance of resources in the implementation of eco strategies. However, tests do not confirm the importance of institutional aspects in the theoretical-conceptual model, which exposes the limited extent of this theory. From the managerial side results show that market forces encourage companies to engage in eco-reputation and green manufacturing process initiatives. However, it appears, according to the data, which aspects of eco-innovation in Chinese companies have not been influenced by the Brazilian market demands.
8

A study of process planning for metal cutting / En studie av produktionsberedning för skärande bearbetning

Anderberg, Staffan January 2009 (has links)
<p>Process planning as a function for competitiveness is often neglected. However, as an intermediary between product development and manufacturing, it holds a key function in transforming product specifications and requirements into a producible process plan. Demands and requirements should be met concurrently as manufacturing costs and lead times are minimised. The focus of this thesis is the act of process planning, where the use of better methodologies, computer-aids and performance measurements are essential parts. Since process planning has the function of transforming demands and requirements, changing customer and regulative requirements are vital to regard. Since environmentally benign products and production increases in importance, the research presented in this thesis includes a CNC machining cost model, which relates machining costs to energy consumption.  The presented results in this thesis are based on quantitative and qualitative studies in the metal working industry.</p><p> </p><p>This thesis has contributed to an enhanced understanding of process planning to achieve better performance and important areas for improvements. Despite a 50 year history of computerised process planning aids, few of these are used in the industry, where manual process planning activities are more common. Process planning aids should be developed around the process planner so that non-value adding activities, such as information management and documentation are minimised in order to allow more resources for value adding activities, such as decision making. This thesis presents a study of systematic process planning in relation to perceived efficiency. This correlation could however not be verified, which opens up for further studies of other possible explanations for process planning efficiency. Process planning improvements in the industry are difficult to make, since there is little focus on process planning activities and limited knowledge about actual performance hereof. This means that measures taken regarding process planning development are difficult to verify.</p> / NFFP4
9

A study of process planning for metal cutting / En studie av produktionsberedning för skärande bearbetning

Anderberg, Staffan January 2009 (has links)
Process planning as a function for competitiveness is often neglected. However, as an intermediary between product development and manufacturing, it holds a key function in transforming product specifications and requirements into a producible process plan. Demands and requirements should be met concurrently as manufacturing costs and lead times are minimised. The focus of this thesis is the act of process planning, where the use of better methodologies, computer-aids and performance measurements are essential parts. Since process planning has the function of transforming demands and requirements, changing customer and regulative requirements are vital to regard. Since environmentally benign products and production increases in importance, the research presented in this thesis includes a CNC machining cost model, which relates machining costs to energy consumption.  The presented results in this thesis are based on quantitative and qualitative studies in the metal working industry.   This thesis has contributed to an enhanced understanding of process planning to achieve better performance and important areas for improvements. Despite a 50 year history of computerised process planning aids, few of these are used in the industry, where manual process planning activities are more common. Process planning aids should be developed around the process planner so that non-value adding activities, such as information management and documentation are minimised in order to allow more resources for value adding activities, such as decision making. This thesis presents a study of systematic process planning in relation to perceived efficiency. This correlation could however not be verified, which opens up for further studies of other possible explanations for process planning efficiency. Process planning improvements in the industry are difficult to make, since there is little focus on process planning activities and limited knowledge about actual performance hereof. This means that measures taken regarding process planning development are difficult to verify. / NFFP4
10

Uma abordagem inovadora para medir a eficiência do ciclo de manufatura por meio de um novo modelo multiobjetivo de análise envoltória de dados / An innovative approach to measuring manufacturing cycle efficiency through a new multiobjective data envelopment analysis model

Ushizima, Carlos Alberto 12 September 2018 (has links)
Submitted by Carlos Alberto Ushizima (caushizima@dglnet.com.br) on 2018-11-08T21:39:33Z No. of bitstreams: 1 Dissertação Carlos A Ushizima.pdf: 3738576 bytes, checksum: 8e4ba3aa41fe88d4ff77e8575bca49bb (MD5) / Approved for entry into archive by Pamella Benevides Gonçalves null (pamella@feg.unesp.br) on 2018-11-12T13:55:31Z (GMT) No. of bitstreams: 1 ushizima_ca_me_guara.pdf: 3738576 bytes, checksum: 8e4ba3aa41fe88d4ff77e8575bca49bb (MD5) / Made available in DSpace on 2018-11-12T13:55:32Z (GMT). No. of bitstreams: 1 ushizima_ca_me_guara.pdf: 3738576 bytes, checksum: 8e4ba3aa41fe88d4ff77e8575bca49bb (MD5) Previous issue date: 2018-09-12 / A estratégia da organização Green e Lean Manufacturing enfatiza a redução de desperdícios, resíduos e seus impactos ambientais, o aumento da eficiência, a melhoria da qualidade e a redução do tempo de ciclo pela eliminação das atividades que não agregam valor. Normalmente, as empresas adotam o indicador Manufacturing Cycle Efficiency para identificar e melhorar seus processos buscando atender aos requisitos da Lean Manufacturing. Este trabalho é classificado como uma pesquisa aplicada, a abordagem do problema é quantitativa e o método utilizado de Modelagem e Simulação, além da técnica não paramétrica da Análise Envoltória de Dados Multi-critério para calcular otimamente um novo indicador denominado Value Added Actcities in Manufacturing Processes (VAAMP) ou Índice de Atividades de Valor Agregado em Processos de Manufatura para medir a eficiência dos processos produtivos por meio de parâmetros da Lean e Green Manufacturing. Uma aplicação em uma indústria multinacional de autopeças foi feita com o objetivo de testar e validar o novo indicador. Como vantagem imediata foi possível aos gestores tratar informações adicionais ao indicador Manufacturing Cycle Efficiency, adotado pela empresa, incorporando outros parâmetros importantes citando como exemplo: a quantidade de sucata, o volume das vendas, a quantidade de peças em processo, os gestores e especialistas em Lean e Green Manufacturing da empresa estudada, que observaram boa adesão à prática dos novos valores calculados, quando comparados aos cálculos tradicionalmente adotados. Outras vantagens deste novo indicador também são destacadas, como o estabelecimento de um ranking de eficiência entre os processos produtivos analisados e a determinação de metas viáveis para tornar eficientes os processos identificados como ineficientes / The strategy of organizational Green & Lean Manufacturing emphasizes on reducing waste and environmental impacts, increasing efficiency, quality improvement, and cycle time reduction by eliminating non-value-added activities. Usually enterprises adopt the indicator Manufacturing Cycle Efficiency to identify and make improvement so as to meet Lean Manufacturing requirements. This work is classified as an applied research, approach of problem is quantitative and based on Modeling and Simulation, in addition to the nonparametric technique the Multi-Criteria Data Envelopment Analysis, to optimally calculate a new indicator, hereby called as Value-Added Activities in Manufacturing Processes, to measure the efficiency of productive processes through Green and Lean Manufacturing parameters. An application of new indicator was made in a multinational auto parts industry with the purpose of validating and testing it. As an immediate advantage of this new indicator, it was possible for managers to insert more information, as incorporating aspects associated with Green Manufacturing, in the calculation of the Manufacturing Cycle Efficiency, making it more consistent and representative of what is happening in practice. Among this additional information on the real processes analyzed, we can mention, for example, the amount of scrap generated, the amount of sales invoicing, the quantity of work in process, the quantity of finished products in stock, among others. The results of a new indicator were validated by specialists in Green & Lean Manufacturing, managers of the studied company, who observed greater adherence to the practice of these new calculated values, when compared to the calculations traditionally adopted. Other a new indicator advantages are also highlighted, such as the establishment of a ranking of efficiency between the productive processes analyzed and the determination of feasible goals to make efficient the processes identified as inefficient

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