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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

Capacity and cost analysis : Implementing a Just-in-time philosophy in annealing operations at Sapa Heat Transfer AB

Björnsson, Anders, Einarsson, David January 2004 (has links)
Our work focuses on an analysis of the processes for full and partial annealing of aluminium coils. Due to inefficient production management these processes show high inventory levels, long lead times and decreased delivery performance. We have also found inadequacies in the ways costs for these processes are distributed. We have established a new process mapping by initially investigating the strategic dimensions of the company and the processes for annealing, in order to later on establish performance measures congruent with the business objectives. Furthermore we have conducted extensive calculations and analyses to facilitate the successful implementation of a Just-in-time production philosophy, including necessary process improvements and redesigns to be made. Our proposed changes will lead to shorter lead times and low levels of WIP, which are important success factors of a JIT-based production philosophy. To do this we have developed a capacity analysis tool with which it is also possible to analyse other processing scenarios or the effect of load changes and/or product mix variations. This tool can also serve as a benchmark for capacity analysis of other processes. Finally, we have been able to establish more accurate costs per machine hour for full and partial annealing to be implemented in the managerial system. We believe that the processes for annealing are not the only ones suffering from poor cost control, why we would suggest that Sapa Heat Transfer investigates the cost distribution in more processes, and also develops and follows better guidelines for cost control.
22

EFFEKTIVISERING AV DELMOMENT I PROCESSKARTLÄGGNING / Efficiency of subsection in the process mapping

Barsom, Daniella, Osama, Rand January 2013 (has links)
Den här C-uppsatsen har gått ut på att göra en processkartläggning på återuppbyggnaden av Vivallaskolans bollhall som har brunnit ner under slutet av oktober 2010. Utifrån processkartläggningen har det gjorts analyser och observationer på aktivitetsflödet. Där framgår det vad som har gått bra och mindre bra. Till det som har gått mindre bra har förslag till lösningar tagits fram. I dessa lösningar ingår metoderna: PDCA (s.21), BIM (s.21) och Ishikawadiagram (s.21), som tydligt visar förbättringsåtgärder. Processkartläggningen och lösningsförslagen har tagits fram utifrån observationer i form av besök på arbetsplatsen samt läsning av litteratur och elektroniska källor. Vid besök och samtal med platschef och snickare har det även uppmärksammats att Lean, vilket är en metod för effektivisering av olika aktivitetsflöden, redan delvis används inom produktionsskedet i detta byggprojekt. Detta har gjorts för att effektivisera och utveckla produktionsskedet kvalitativt. I takt med att processkartläggningen har blivit kartlagd och analyserad kan de inblandade i projektet tydligt följa förslag till förbättringar. Detta för att förhindra att eventuella problem som har tagits upp i den här C-uppsatsen uppstår. Dessa förslag kan de använda sig av till nästkommande projekt redan i projekteringsskedet. / This thesis involves a process mapping to the rebuilding of the gymnasium of Vivallaskolan that burned down at the end of October 2010. Analyses and observations in the activity flow are based on the process mapping. There it shows what subsection that has gone well and less well. Suggested solutions have been made to the problems that gone less well. These solutions show clearly how they can be improved and are based on the following methods: the PDCA-cycle (page 21), BIM (page 21) and Ishikawa diagrams (page 21). This process mapping and suggested solutions are based on observations at the construction site together with reading literature and electronic sources. During visits and conversations with the construction manager and carpenters it have been recognized that Lean, which is a method for efficiency of different activity flows, are already partially used in the production of this construction project. These suggested solutions have been made to improve and develop the production phase qualitatively. During the survey and analysis of the process mapping, those who are involved in this construction project can clearly see and follow these suggested solutions. These are made to avoid upcoming problems which have been described in this thesis. These solutions can be used to upcoming construction projects already at the designing and calculation phase.
23

Creation of a Simulation Model based upon Process Mapping within Pipeline Management at Scania

Ovesson, Elin, Stadler, Niklas January 2013 (has links)
This is a Master’s Thesis that has been carried out at the Global Outbound Logistics department at Scania. Scania manufactures trucks, buses and engines. Some trucks and buses are delivered to markets where it, due to reduced customs duties and cheaper manpower, is more profitable to do the assembly locally at so called Regional Product Centres (RPCs). Since the components are produced far away from the RPC markets the lead times become long. In addition, the customers’ buying behaviour at the RPC markets is often not comparable to the European culture were a customer can accept to wait for weeks for a unit to be delivered. The long lead time in combination with the customer behaviour implies that the RPCs need to keep a certain selection of standard models of buses and trucks in stock. It has turned out to be difficult for the pipeline managers at the RPCs to place order volumes that correspond well to what will be delivered to the business units or distributors later on. The result of this is high stock levels at the RPCs, which leads to an important amount of tied up capital. Due to what is explained above, the purpose of this study is “to create a simulation model, based upon a process mapping, that visualises future volume levels in the pipeline due to different demand and ordering scenarios”. The short term target, which is also the target of this study, is to increase the RPCs understanding for how different demand and ordering scenarios influence the future volume levels in the pipeline. The long term target is to reduce tied up capital by adjusting buffer levels and lead times, while still ensuring a certain service level. The model should contribute to more accurate decision making with respect to the previous mentioned aspects. First, a high level process mapping was made in order to select which flows that were suitable for being subject for a detailed mapping. Second, a detailed mapping was made during which several RPC-, process- and function responsible were interviewed. After the detailed mapping, common denominators between the flows were identified and all activities were clustered into a solution that could be generalised and suitable for all flows. Factors such as lead times, deviation risks and capacity limitations were taken into account during the aggregation of activities. When a common view of the different RPC flows had been created, the mathematical relationships for how the goods can move throughout the process could be established. Then, the development and validation of the simulation model, which was an iterative process, could start. A directive was to build the simulation model in Microsoft Excel. Interviews were made with experienced model creators in order to find out how to create a user-friendly and robust model. The creation of the simulation model started with the development of a structure and then the content of each part was defined. A final validation, which consisted of sensitivity analysis and user trials, was finally done in order to ensure the simulation models functioning and accuracy. To conclude, a simulation model that will serve as a helpful tool for the RPCs when they are to decide which order volumes to place has been created. By clearly visualising the simulation results, the simulation model will hopefully increase the RPCs’ comprehension for how the pipeline works with respect to different ordering and demand scenarios. On top of this, the method used, the process mapping and the mathematical relationships that have been defined are important input for a possible future development of a more permanent and robust non-Microsoft Excel solution. This solution could probably be even more precise, automatically updated and have an even higher granularity.
24

Processkartläggning avförmedlingsuppdraget : med fokus på förbättringsområden

Andersson, Hanna, Enström, Caroline, Gedda, Johan January 2012 (has links)
I denna rapport redovisas för förmedlingsprocessen för småhus med typkod 220 och samtliga moment som ingår från början till genomfört uppdrag. Fokus har riktats på att identifiera förbättringsområden och därigenom hitta åtgärdsförslag. Rapporten skall syfta till att fungera som ett stöd och vara ett vägledande hjälpmedel för såväl fastighetsmäklare som privatpersoner i sin roll som säljare och köpare. Litteraturstudier och handledning har legat till grund för den processkarta som upprättats och illustrerats. Utifrån denna har en förstudie gjorts genom intervjuer med fem verksamma fastighetsmäklare på Fastighetsbyrån i Alingsås. Därefter genomfördes djupintervjuer med tre slumpvis utvalda fastighetsmäklare på olika orter och kontor, för att identifiera problemområden. Varje moment i processen har beskrivits i text för att ge en bättre förståelse för kartans innebörd. Vidare diskussion och analys har resulterat till förslag på förbättringsåtgärder inom förmedlingsprocessen. Resultatet redovisar att majoriteten av de intervjuade fastighetsmäklarna har upplevt att moment och arbetssätt inom förmedlingsprocessen till viss grad går att förbättra. Därtill kan det konstateras att förmedlingsprocessen skiljer sig i både utförande och tid beroende på om försäljningen görs i en storstad eller på en mindre ort. Majoriteten av de intervjuade fastighetsmäklarna pekar särskilt på vikten av att skapa och upprätthålla goda relationer med samarbetspartners och kollegor i branschen. Detta anses vara av väsentlig betydelse för att affärer som är beroende av en tredje part ska fortgå med så få hinder som möjligt. Det kan även konstateras att flera av de problemställningar som framkommit beror på externa makrofaktorer som fastighetsmäklaren själv inte kan påverka. Omständigheter som berör världsekonomin, ränteläget, ställningen på fastighetsmarknaden, medias spekulationer, lagar och förordningar utgör faktorer utom fastighetsmäklarens kontroll. Vidare kan det fastställas att den nya fastighetsmäklarlag som trädde i kraft den 1 juli 2011 har bidragit till att flera tidigare problem redan bearbetats och ändrats. Detta projekt har verkat för att lyfta fram ytterligare några moment där åtgärder skulle kunna underlätta arbetsgången för fastighetsmäklare, bland annat genom ett informationsblad till spekulant. / This report describes the sales process of type code 220 single-family homes, including necessary procedural steps. The focus of the report is to identify key areas needing improvement in order to ascertain potential solutions. The report is intended to act as both a support mechanism and a guide for real estate agents and private individuals in their roles as buyers and sellers. A process-map was developed based on research and guidance, and is described within the report. Problem areas were identified using the process-map during comprehensive interviews, and every step in the process is explained in detail in order to illustrate the process-map’s purpose. Further discussion and analysis has led to suggestions for improvement of the sales process. The results shows that the majority of interviewed real estate agents believe the sales process to some extent can be improved. The majority of the interviewed real estate agents points out the importance of creating and maintain good relations with partners and colleagues in the same economic area. This is considered to be essential for businesses that rely on a third person should proceed with as few obstacles as possible. It is also clear that many of the problems that emerged due to external factors that the real estate agents themselves can´t influence. Factors affecting the world economy, interest rates, situation of the property market, speculations among media, laws and regulations are factors beyond the real estate agent´s control. However, after further discussion it became evident that active real estate agents already considered the process inadequate or excessively time consuming. It is also evident that many of the problem areas were due to external factors not influenced by real estate agents. Furthermore, the new real estate law which was implemented July 1, 2011 contributed to several problem areas already identified being addressed and resolved. This report has led to the identification of a process which would make the work easier.
25

Integrated Control of Solidification Microstructure and Melt Pool Dimensions In Additive Manufacturing Of Ti - 6Al - 4V

Gockel, Joy E. 01 May 2014 (has links)
Additive manufacturing (AM) offers reduced material waste and energy usage, as well as an increase in precision. Direct metal AM is used not only for prototyping, but to produce final production parts in the aerospace, medical, automotive and other industries. Process mapping is an approach that represents process outcomes in terms of process input variables. Solidification microstructure process maps are developed for single bead and thin wall deposits of Ti-6Al-4V via an electron beam wire feed and electron beam powder bed AM process. Process variable combinations yielding constant beta grain size and morphology are identified. Comparison with the process maps for melt pool geometry shows that by maintaining a constant melt pool cross sectional area, a constant grain size will also be achieved. Additionally, the grain morphology boundaries are similar to curves of constant melt pool aspect ratio. Experimental results are presented to support the numerical predictions and identify a proportional size scaling between beta grain widths and melt pool widths. Results demonstrate that in situ, indirect control of solidification microstructure is possible through direct melt pool dimension control. The ability to control solidification microstructure can greatly accelerate AM process qualification potentially allow for tailored microstructure to the desired application.
26

Introducing Continuous Improvement in an R&D Facility : Action research in the pharmaceutical industry

Messier, Alexis January 2014 (has links)
Continuous Improvement processes are commonly used by many organizations facing competitive pressure. By implementing continuous incremental changes, it allows optimizing resources while maintaining flexibility. However, it requires significant resources and involvement from all levels of management, as well as field workers. Continuous Improvement is based on the study of processes and the identification of recurrent problems; therefore it is particularly adapted to manufacturing activities and other repetitive processes. R&D (Research and Development) activities are less repetitive and tend to be iterative, which make them more difficult to study. Yet these activities represent a strong competitive asset and an early mistake or misunderstanding might have a significant cost. The objective of this project was to study the deployment of Continuous Improvement for R&D processes through a literature review and a case study in the pharmaceutical industry. Action research has been the research method that has been employed; the particularity of this method is that the researcher participates actively to the studied change. It resulted in the identification of some characteristics that have to be taken into account in the deployment of improvement activities. First the culture is based on problem-solving, which increase the efficiency of data study and analytical method whilst formalization tools are less efficient, as well as performance indicators related to improvement activities. Besides, the need of customers (both internal and external) is difficult to define and is subject to evolution; this issue tends to be aggravated by a lack of communication. Moreover, development projects being unique and highly iterative, it is recommended to study processes at a more conceptual level, although no specific mapping tool seems particularly adapted. Finally, beside the study of general processes, the study of each individual project (project reviews) allows individual and collective learning. This project also propose a tool allowing the study of information flows between activities and teams in order to reduce mismatch between need and reality (and thus communication issues). This tool relies on the use of local SIPOC diagrams to represent activities and the mapping of flows between each of them.
27

En studie över effektiviseringsmöjligheter av fjärrvärmeinstallationer i småhus / A study of possibilities for increasing efficiency of district heating installation in houses

Håkansson, Andrea, Andersson, Petra January 2014 (has links)
Syfte: Syftet med examensarbetet är att undersöka möjligheter till effektivisering av fjärrvärmeinstallationer i småhus med hjälp Lean. Detta har gjorts genom att besvara de tre följande frågeställningarna: Hur ser en fjärrvärmeinstallation i småhus ut i dagsläget? Vilka slöserier går att identifiera i processen för fjärrvärmeinstallation i småhus? Hur kan slöserier i processen för fjärrvärmeinstallation i småhus minskas? Metod: För att uppfylla examensarbetets syfte har en fallstudie genomförts på Jönköping Energi som är en leverantör av fjärrvärme. Där har intervjuer och dokumentationsstudier använts som datainsamlingsmetoder. Litteraturstudier har gjorts för att samla in information kring teorier som sedan använts för att utvärdera och analysera empirin. Resultat: Genom studien har slöserier identifierats i processen för fjärrvärmeinstallation i småhus. Det största slöseriet som identifierats är väntan som uppstår mellan delprocesserna, vilken uppgår till 20 % av den totala ledtiden för installationen. Genom att införa ett informationssystem som täcker glappet mellan entreprenörerna och fallstudieföretaget, förändrad tidsplanering samt arbete med parallella processer anses denna väntan kunna minskas. Implikationer: Denna studie visar att med hjälp av Lean kan processen för fjärrvärmeinstallation i småhus effektiviseras och att ledtiden för processen kan förkortas genom eliminering av slöserier. Studien visar också att genom att använda periodlös planering kan ledtiden förkortas ytterligare då tidsplaneringen anpassas efter verksamheten. Begränsningar: Studien som genomförts baseras på empiri som samlats in på ett fallstudieföretag, genom att öka antalet fallstudier samt genomföra dessa på fler en ett företag ökar generaliserbarheten i resultaten. / Purpose: The purpose of this study is to investigate the possibilities for improving the efficiency of district heating installations in houses by using Lean. This is done by answering the following three questions: How is a district heating installation implemented? What types of wastes can be identified in the process of district heating installations in houses? How can wastes in the process of district heating installations in houses be reduced? Method: In order to fulfill the purpose of the study a case study has been conducted at Jönköping Energi, a supplier of district heating. Interviews and documentation studies have been used as data collection methods. Literature studies have been made to collect information on theories that were used to evaluate and analyze empirical data. Results: Wastes in the process of district heating in houses has been identified in the study. The biggest identified waste is the wait that occurs between the sub-processes, where wait reach up to 20 % of the total lead time of the installation. By implementing an information system, introducing changes in scheduling and start working in with parallel processes this wait can be reduced. Implications: This study shows that by using Lean the process of district heating installations in houses can be more efficient and that the lead time for the process can be shortened by eliminating wastes. The study also shows that by using bucketless planning, lead time can be shortened further when scheduling adapts to the process. Limitations: The study was carried out based on only one case study. By increasing the number of case studies and by carry those out in more than one company the generalizability of the results will be increased.
28

Optimization combined with process mapping for maximizing product utilization : Investigating the utilization of products in sawmills, a case study

Höglund, Jonas January 2018 (has links)
The handling and utilization of products is an important factor in organization that strive towards and optimal operation, where different methods in the handling of products have a direct effect on the organizations results. This is a case study where a sawmill with a process that is repeated for each new order in the sorting- and packaging of timber. For each scenario, an operator is faced with a decision, where the result of the organization is directly affected by the decision that is made. The decision in question consist of an amount of trays of timber that must be combined in order to meet a constraint in the height of each delivered package. The purpose with this study is to investigate how optimization combined with process mapping can help the organization in maximizing its utilization of products. The study was performed with a mixed methods approach, where a process map was developed to gain understanding of the process. An optimization model was developed and run given collected data. In the process mapping it became clear that for each combination of trays, there is a downgrading in length and/or quality, which affects the total value of the combination. A comparison of the results between the optimization models’ and operators’ solutions showed a theoretical saving of 3 655 435 kr annually, and an increase in product utilization of 3,81 percentage in this process. The results of the study shows that optimization combined with process mapping is effective in the terms of minimizing costs dependent on a decision maker.
29

Mapeamento estático de processos MPI com emparelhamento perfeito de custo máximo em cluster homogêneo de multi-cores / Static MPI processes mapping using maximum weighted perfect matching at homogeneous multi-core clusters

Ferreira, Manuela Klanovicz January 2012 (has links)
Um importante fator que precisa ser considerado para alcançar alto desempenho em aplicações paralelas é a distribuição dos processos nos núcleos do sistema, denominada mapeamento de processos. Mesmo o mapeamento estático de processos é um problema NP-difícil. Por esse motivo, são utilizadas heurísticas que dependem da aplicação e do hardware no qual a aplicação será mapeada. Nas arquiteturas atuais, além da possibilidade de haver mais de um processador por nó do cluster, é possível haver mais de um núcleo de processamento por processador, assim, o mapeamento estático de processos pode considerar pelo menos três níveis de comunicação entre os processos que executam em um cluster multi-core: intra-chip, intra-nó e inter-nó. Este trabalho propõe a heurística MapEME (Mapeamento Estático MPI com Emparelhamento) que emprega o Emparelhamento Perfeito de Custo Máximo (EPCM) no cálculo do mapeamento estático de processos paralelos MPI em processadores multi-core. Os resultados alcançados pelo mapeamento gerado pela MapEME são comparados aos resultados obtidos pelo mapeamento gerado pela aplicação Scotch, que utiliza o Biparticionamento Recursivo Dual (BRD), já utilizado como heurística para mapeamento estático de processos. Ambas as heurísticas são comparadas à Busca Exaustiva (BE) para verificar o quanto estão próximas do ótimo. Os três métodos têm a complexidade e o ganho no tempo de execução em ralação à distribuição padrão da biblioteca MPICH2 comparados entre si. A principal contribuição deste trabalho é mostrar que a heurística EPCM apresenta ganho de até 40% equivalente a já difundida BRD, e possui uma complexidade menor ao ser aplicado em um cluster multi-core que compartilha cache nível 2 a cada dois núcleos. / An important factor that must be considered to achieve high performance on parallel applications is the mapping of processes on cores. However, since this is defined as an NP-Hard problem, it requires different mapping heuristics that depends on the application and the hardware on which it will be mapped. On the current architectures we can have more than one multi-core processors per node, and consequently the process mapping can consider three process communication types: intrachip, intranode and internode. This work propose the MapEME (Static Mapping MPI using Matching) that use the Maximum Weighted Perfect Matching (MWPM) to calculate the static process mapping and analyze its performance. The results provided by MapEME are compared with the results of application Scotch. It uses Dual Recursive Bipartitioning (DRB), an already used heuristics for static mapping. Both heuristics are compared with Exhaustive Search (ES) to verify how much the two heuristics are near the optimum. The three methods have theirs complexities analyzed. Also the mapping gain when compared with the standard MPICH2 distribution was measured. The main contribution of this work is to show that the heuristic, EPCM, provides gain up to 40%, close of DRB gain. Furthermore, EPCM has a lower complexity when applied to a multicore cluster that shares L2 cache every two cores.
30

Melhoria do processo de produção de tecidos metálicos na fabricação de pneus

Rodrigues, Jordana Roider January 2014 (has links)
A melhoria de processos é um tema abordado em diversos setores. Este trabalho concentrou-se na melhoria do processo de produção de tecidos metálicos usados como material de reforço na fabricação de pneus radiais. O estudo foi realizado em uma indústria fabricante de pneus, em uma calandra de configuração Z e teve como objetivo aprofundar os conhecimentos a respeito deste processo identificando oportunidades de melhorias para reduzir perdas causadas por problemas qualitativos. Além disso, buscou melhorar a qualidade percebida pelo cliente interno sem afetar a qualidade do produto final, percebida pelo cliente externo. Para tanto, foi realizado um mapeamento do processo produtivo em questão, seguido de um estudo do efeito das temperaturas neste processo. O mapeamento mostrou que muitas etapas possuem influência direta na qualidade dos tecidos, as oportunidades de melhoria foram destacadas durante e após o mapeamento e estão relacionadas principalmente ao controle das temperaturas da calandra e dos moinhos, à automatização do processo, aos procedimentos operacionais e à instalação de dispositivos de controle e alerta. Uma vez que o controle das temperaturas de toda a linha da calandra resultou ser um fator crítico para o processo, realizou-se um estudo do efeito das temperaturas usadas durante a produção, a partir do uso da metodologia de Projeto de Experimentos com a aplicação de um Projeto Fatorial 25-1 sem repetição Quatro variáveis de resposta foram estudadas: quantidade de grumos pré-vulcanizados, aderência tecido-tecido, reversão de enxofre e adesão borracha-metal. Os fatores controláveis usados foram: temperatura dos moinhos alimentadores, temperatura dos cilindros 1 e 4, temperatura dos cilindros 2 e 3, temperatura dos tambores de resfriamento e temperatura do aquecimento das cordas metálicas. Pela otimização das variáveis de resposta, chegou-se aos valores ótimos para o processo, sendo todos eles no seu nível alto, com exceção da temperatura dos cilindros 2 e 3 que apresentou o melhor valor no nível baixo. Os resultados deste trabalho aprofundaram os conhecimentos num processo que, apesar de muito antigo, ainda possui poucos textos publicados a respeito. Adicionalmente, forneceu uma otimização experimental para as afirmações encontradas na literatura sobre a importância do controle de temperaturas no processo de fabricação de tecidos metálicos. / The process improvement is a topic widely used in several sectors. In this work this topic deals with improving the production process of metallic fabrics used as reinforcement material for radial tires. The study was carried out in a tire industry in a Z configuration calender and aims to deepen the knowledge about this process by identifying improvement opportunities to reduce losses caused by quality problems in metallic fabrics. It also seeks to improve the quality perceived by internal costumer without affecting the quality of the final product, perceived by the external customer. Thus, a mapping of the production process in question was made, followed by a study of the effect of temperature in this manufacturing process. The mapping shown that many steps have direct influence on fabric quality, the opportunities for improvement were highlighted during and after the mapping and are related mainly to control the temperature of the calender and mills, to process automation, operational procedures and the installation of devices for control and alert. Since the temperature control of whole calender line proved to be a critical factor in the process, a study of the effect of the temperatures used during the production was performed from the use of the design of experiments methodology with the application of a factorial design 25-1, without replication Four response variables were studied: number of pre vulcanized lumps, tack, sulfur reversion and steel-rubber adhesion. The controllable factors chosen were: feeder mills temperature, temperature of rolls 1 and 4 of the calender, temperature of rolls 2 and 3 of the calender, temperature of cooling drums and heating temperature of steel cords. By the optimization of the response variables, it was reached the optimum values for the process, all of which are in its high level except for the temperature of the rolls 2 and 3 which showed the best value in the low level. These results obtained deepened knowledge in a process which, though very old, still has a few articles published. Additionally, it provided quantitative data to the statements found in the literature about the importance of temperature control in the manufacturing process of metallic fabrics.

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