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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.
21

Toward Lean Remanufacturing : Challenges and Improvements in Material and Information Flows

Kurilova-Pališaitienė, Jelena January 2015 (has links)
Remanufacturing is an environmentally sound material recovery option which is essential to compete for sustainable manufacturing. The aim with remanufacturing at a majority of companies is to prolong physical product performance by delivering the same or betterthan-original product quality. In general, remanufacturing is an industrial process that brings used products back to useful life by requiring less effort than is demanded by the initial production process. Consequently, from a product life-cycle perspective, remanufacturing generates great product value. Remanufacturers lag behind manufacturers since they often face complex and unpredictable material and information flows. Based on a review of remanufacturing research, remanufacturing challenges in material and information flows can be classified into three groups: insufficient product quality, long and unstable process lead times, and an unpredictable level of inventory. While some remanufacturing researchers state that manufacturing and remanufacturing are significantly different, they have more in common than many other processes operations. Therefore, to sustain competitive remanufacturing, companies investigate an opportunity for improvement through the employment of lean production that generates significant benefits for manufacturers. In order to investigate the potential to address remanufacturing challenges by lean production, a Minimum time for material and information flow analysis (MiniMifa) method was developed. This method originates from the value stream mapping (VSM) method, broadly practiced to bring lean to manufacturing companies. The focus of MiniMifa was to collect empirical data on the identified groups of remanufacturing challenges from the remanufacturing perspective, and to provide a basis for the development of improvements originating from lean principles. Lean production was selected for this research due to its system perspective on material and information flows. Among the defined lean principles in remanufacturing, a pull principle was investigated at the case companies. The suggested principle demonstrated a reduction in lead time, followed by improvements in inventory level and product quality. However, in order to become lean, remanufacturers have to overcome three levels of lean remanufacturing challenges: external and internal challenges as well as lean wastes. Finally, this research reduces the gap between academia and industry by contributing with a possible solution to the identified remanufacturing challenges in material and information flows.
22

Towards Design Automation for Additive Manufacturing : A Multidisciplinary Optimization approach

Wiberg, Anton January 2019 (has links)
In recent decades, the development of computer-controlled manufacturing by adding materiallayer by layer, called Additive Manufacturing (AM), has developed at a rapid pace. The technologyadds possibilities to the manufacturing of geometries that are not possible, or at leastnot economically feasible, to manufacture by more conventional manufacturing methods. AMcomes with the idea that complexity is free, meaning that complex geometries are as expensiveto manufacture as simple geometries. This is partly true, but there remain several design rulesthat needs to be considered before manufacturing. The research field Design for Additive Manufacturing(DfAM) consists of research that aims to take advantage of the possibilities of AMwhile considering the limitations of the technique. Computer Aided technologies (CAx) is the name of the usage of methods and software thataim to support a digital product development process. CAx includes software and methodsfor design, the evaluation of designs, manufacturing support, and other things. The commongoal with all CAx disciplines is to achieve better products at a lower cost and with a shorterdevelopment time. The work presented in this thesis bridges DfAM with CAx with the aim of achieving designautomation for AM. The work reviews the current DfAM process and proposes a new integratedDfAM process that considers the functionality and manufacturing of components. Selectedparts of the proposed process are implemented in a case study in order to evaluate theproposed process. In addition, a tool that supports part of the design process is developed. The proposed design process implements Multidisciplinary Design Optimization (MDO) witha parametric CAD model that is evaluated from functional and manufacturing perspectives. Inthe implementation, a structural component is designed using the MDO framework, which includesComputer Aided Engineering (CAE) models for structural evaluation, the calculation ofweight, and how much support material that needs to be added during manufacturing. Thecomponent is optimized for the reduction of weight and minimization of support material,while the stress levels in the component are constrained. The developed tool uses methodsfor high level Parametric CAD modelling to simplify the creation of parametric CAD modelsbased on Topology Optimization (TO) results. The work concludes that the implementation of CAx technologies in the DfAM process enablesa more automated design process with less manual design iterations than traditional DfAM processes.It also discusses and presents directions for further research to achieve a fully automateddesign process for Additive Manufacturing. / AddMan
23

Optimization of Unmanned Aerial Vehicles : Expanding the Multidisciplinary Capabilities

Papageorgiou, Athanasios January 2017 (has links)
Over the last decade, Unmanned Aerial Vehicles (UAVs) have experienced an accelerated growth, and nowadays they are being deployed in a variety of missions that have traditionally been covered by manned aircraft. This unprecedented market expansion has created new and unforeseen challenges for the manufacturing industry which is now called to further reduce the idea-to-market times while simultaneously delivering designs of even higher performance. In this environment of uncertainty and risk, it is without a doubt crucial for the involved actors to find ways to secure their strategic advantage, and hence, implementing the latest design tools has become a critical consideration in every Product Development Process (PDP). To this end, a method that has been frequently applied in the PDP and has shown many successful results in the development of complex engineering products is Multidisciplinary Design Optimization (MDO). In general, MDO can bring additional knowledge regarding the best-suited designs much earlier in the process, and in this respect, it can lead to significant cost and time savings by reducing the total number of refinement iterations. Nevertheless, the organizational and cultural integration of MDO has been often overlooked, while at the same time, several technical aspects of the method for UAV design are still at an elementary level. On the whole, research on MDO is showing a slow progress, and to this date, there are many limitations in both the disciplinary models and the available analysis capabilities. In light of the above, this thesis focuses on the particulars of the MDO methodology, and more specifically, on how it can be best adapted and evolved in order to enhance the development process of UAVs. The primary objective is to study the current trends and gaps of the MDO practices in UAV applications, and subsequently to build upon that and explore how these can be included in a roadmap that will be able to serve a guide for newcomers in the field. Compared to other studies, the problem is herein approached from both a technical as well as organizational perspective, and thus, this research not only aims to propose techniques that can lead to better designs but also solutions that will be meaningful to the PDP. Having established the above foundation, this work shows that the traditional MDO frameworks for UAV design have been neglecting several important features, and it elaborates on how those novel elements can be modeled in order to enable a better integration of MDO into the organizational functions. Overall, this thesis presents quantitative and qualitative data which illustrate the effectiveness of the new framework enhancements in the development process of UAVs, and concludes with discussions on the possible improvement directions towards achieving more and better MDO capabilities.
24

Utökad sätesjustering av “The Armadillo“

Österberg, Ellen, Vilén, Anna January 2018 (has links)
This report describes a solution to an adjustment problem found on “The Armadillo”. This product can be described as a bicycle, but with four wheels instead of two, and has a somewhat more complex construction than an electric bicycle. In today’s construction there are difficulties in using the bike if the driver is not within the range of 170-190 cm tall, which obviously limits the user of the product. The main user are those who work with the product. The task of the project was therefore to find a solution to this problem, with free hands without major limitations. This has been done in cooperation the company that owns the product, Velove, where a couple of visits have been made to study the design further, as well as examine the possibilities and limitations that exist. Methods such as Fredy Olsson with small modification have been used, this has simplified the work as a clear structure has been obtained on approaches. The project group has used different ideas to generating and evaluating product ideas, including where we included other students for inspiration, in order to reach a promising concept within the group. Two ready-made digital prototype concepts have been developed in Catia V5, where one of them has advanced into a physical prototype in plastic material. The construction allows a longer span and allows more drivers to use today’s Armadillo. The solution is another smaller rail that goes over the today’s existing rail witch makes it possible to further adjust the length span for the driver. The construction is a superstructure on the existing Armadillo and does not require a reconstruction of the bike.
25

Simuleringsbaserad optimering av produktionsflöde

Ericsson, Alexander, Gutestam, Elliot January 2018 (has links)
Detta examensarbete har utförts i samarbete med högskolan i Skövde med syftet att genom simulering och optimering påvisa produktionstekniska parametrars påverkan på ett systems prestanda. Examensarbetets mål var att från data ta fram en simuleringsmodell som på ett korrekt sätt avspeglade verkligheten och som kunde användas vid optimering.  En metod för modellbygge togs fram genom en kombination av teorier från Banks (1998) och Lundgren et al. (2010), som sedan praktiserades genom att bygga en modell på data från en verklig produktionsanläggning. Frågeställningen och kraven som utarbetats tillsammans med uppdragsgivaren gällande modellens prestanda utvärderades innan optimeringsparametrar för sekvens, batch-storlekar samt Buffer- och Store-kapacitet definierades och stiftades. Det resultat som optimeringen genererade analyserades, utvärderades och jämfördes med resultat från egna experiment för att säkerställa dess trovärdighet.  Projektet har bidragit med en ny syn på det produktionsflöde som simulerats och visat att det inte alltid är de uppenbara parametrarna som påverkar processen mest. Resultatet visar på förbättring av total kapacitet med 64%, samt en ledtid som kortades ner med över 24 timmar. Arbetet belyser fördelarna för ett företag att använda sig av simulering i sitt arbete med produktionsutveckling, för att minimera risken att lägga resurser på förbättringar med lägre förbättringspotential än andra.  Den simuleringsmodell som tagits fram och den djupare förståelsen för densamma, kommer ligga till grund för fortsatt arbete med att undersöka produktionstekniska parametrar och hur det korrelerar med varandra. / This thesis project has been carried out in collaboration with Skövde University with the purpose of demonstrating, through simulation and optimization, production parameters impact on a system’s overall performance. The aim of the thesis was to create a simulation model from production data that accurately reflect a real-life system and could be used for optimization.  A method of simulation model construction was developed through a combination of theories from Banks (1998) and Lundgren et al. (2010), which were practiced by building a model based on data from a real production facility. The research questions and requirements were developed with the client regarding the performance of the model and were evaluated before optimization parameters for sequence, batch-size and Buffer- and Store capacity were defined and established. The result that the optimization generated was analyzed, evaluated, and compared to results from own experiments to ensure its credibility.  The project has contributed to a new view of the production flow that was simulated and showed that the most obvious parameters are not always the ones that affect the process the most. The results show an improvement of 64% in total capacity and over 24 hours shorter lead time. The report highlights a company’s benefits with using simulation in its work with production development. Especially to minimize the risk of wasting resources to improvements with lower potential than others.  The simulation model developed in the project will serve as basis for further work in understanding and investigating productions technical parameters and their correlations with each other.
26

Exploring value proposition of service offerings in telematics system

Achi, Raghukulesh January 2018 (has links)
Services are making a huge impact in the business sector especially in the developed countries. As services are customer-centric, there is a need for an enhanced process framework connected to integrated service development. Such a framework should ideally address value propositions meeting specific customer needs in identifying corresponding service offerings. In this context, this thesis aims to explore on how value propositions are defined, developed, and communicated during the introduction of service offerings and to identify the ways to improve the process of value propositions. The work is carried out in the context of a major (Swedish) manufacturing company within a specific product context, namely, the telematics system. The main data collection methods are personal observations, semi-structured interviews, meetings, and company documents. The study seeks to answer three questions: First, what are the value propositions addressed by the current service offerings in telematics system in the context of heavy-duty vehicle equipment? Second, how value propositions are created during the development of these services offerings? Third, how can the service offerings for telematics system be improved through the process of value proposition? The study found that two types of value propositions namely customer value proposition and stakeholder value proposition are addressed by the service offerings in telematics system. Additionally, it is found that value propositions are created in relation to service offerings. Finally, the thesis proposes a six-step conceptual framework to create better value propositions during the development of service offerings. The presented framework is applied to the current value proposition process at the case company and improvement suggestions are proposed, which can impact the service offerings in the near future. The thesis has contributions to enhance or create new service offerings through addressing the value propositions and applying them. The results are beneficial for managers and developers who work in developing the future state scenarios or business models.
27

Projektanalys av Delta och Gamma / Project analysis of Delta & Gamma

Hermansson, Fred, Hellström, Simon January 2018 (has links)
No description available.
28

Automation, attachment of lids in ventilation ducts / Automatisering, montering av lock i ventilations kanaler

Pedro, Simon January 2018 (has links)
This master thesis has been written to design and develop an automated solution which can attach protection lids in the ends of the ventilation ducts as they are manufactured. A danish factory within the group are using a solution which enables the manufacturing process of ventilation ducts to be automated which Lindab also want to implement in their Swedish factories. However, as the conditions which the ducts are required to be delivered in are much tougher in Sweden, lids are attached on the ends of the duct to prevent contamination. As these lids are manually attached there is no financial incentive for Lindab to automate the manufacturing process of the ventilation ducts as the operators still have to remain to attach the lids. The thesis covers the product development of automating the lid attachment. Through different elimination matrices and evaluation against the requirement specication was a final concept chosen. In addition to product development, a background investigation was also performed to examine for what reasons the automation was desired but also what advantages in production efficiency an automatic solution provides. The automation was solved by constructing a mount station where every duct dimension are fixated in the same radial axis which facilitates the process for the expanding mechanical grippers to attach the lids in the pipes. The lids are picked up by the grippers from conveyor belts where they are stored in stacks. In order to enable the lids ability to stack as well as improve their shape rigidity, the lids were redesigned with the addition of a radial reinforced rib pattern which extends over the entire bottom as well as a heel placed in the middle of the mantle surface which is in contact with the duct.
29

Digitalization strategy for Scania Cab Assembly

Fuglås, Jonas, Lindgren, Amund January 2018 (has links)
With changing market demands such as individualization, volatility and sustainability, the current manufacturing environment at Scania is subject to an increasing need for change. This, together with the availability of more advanced technology and digitalization has sparked the fourth industrial revolution. It has been named Industry 4.0 and considers digitalization in a manufacturing environment. As a result, the purpose of this thesis is to outline the potential of increased digitalization for logistics and manufacturing at Scania Oskarshamn. This will be done by developing a digitalization strategy that encapsulates the core of Industry 4.0 and a roadmap to guide Scania in their development towards a future digitalized manufacturing environment. The study will consider two core functions of Industry 4.0 as the cornerstones of digitalization; consciousness and interoperability. Consciousness focuses on the level of digitalization within the system. With interoperability, integration throughout the whole supply chain and how it relates to the manufacturing environment. As a result, the study is separated into three main parts: Scania today, Scania 2030 and the gap in-between. For all three parts, three areas of focus will be the basis for the analysis. First, the level of digitalization will be analyzed. This is done in regards to the first core function, consciousness. Second, the level of process maturity will be analyzed. This is done in regards to the second core function, interoperability. Third, synergies between logistics and manufacturing will be analyzed. From the conducted analysis of the current state at Scania, the 2030 scenario and the gap inbetween, the digitalization strategy for Scania focuses on the two identified functions. Three key steps has been developed for each function.
30

Överproduktion och dess samband med ekonomisk hållbarhet : Faktorer som bidrar till överproduktion / Overproduction and its Connection with Economic Sustainability : Factors that Contributes to Overproduction.

Almström, Rasmus, Falk, Agust January 2018 (has links)
Abstract   Purpose– The purpose of this study is to investigate factors that contribute to overproduction and what economic consequence overproduction has. To fulfil the purpose, two research questions has been formulated: Why does overproduction take place in companies with CNC-machines? How does overproduction affect cost items that contributes to economic sustainability? Method– To fulfil the study’s purpose a single case study has been conducted on a manufacturing company within the automotive industry. Interviews, document studies and a focus group have been the methods for the empirical data collection. The empirical data has been analysed together with the theoretical framework and created the study’s result.      Results– The study resulted in identifying several cost items that are affected by overproduction and different factors that contribute to overproduction have been identified.    Implications – The study contributed with new information to the knowledge gap regarding overproduction and the consequences of it. Findings from the study can be used as a template for companies that are interested as to which factors contribute to overproduction.    Limitations– To conduct the study one focal company was used, the focal company is of a manufacturing type with a CNC-machine park and are active in the automotive industry. Because of the characteristics in the automotive industry and the use of only one focal company the generalizability of the study is reduced. To increase the generalizability further studies are required.    Keywords– Overproduction, economic sustainability, automotive, Leagile, Overall Equipment Efficiency (OEE), Economic Order Quantity (EOQ), Just-In-Time (JIT).

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