89 resultados para Causal processes


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Sustainability and recycling are core values in today’s industrial operations. New materials, products and processes need to be designed in such a way as to consume fewer of the diminishing resources we have available and to put as little strain on the environment as possible. An integral part of this is cleaning and recycling. New processes are to be designed to improve the efficiency in this aspect. Wastewater, including municipal wastewaters, is treated in several steps including chemical and mechanical cleaning of waters. Well-cleaned water can be recycled and reused. Clean water for everyone is one of the greatest challenges we are facing today. Ferric sulphate, made by oxidation from ferrous sulphate, is used in water purification. The oxidation of ferrous sulphate, FeSO4, to ferric sulphate in acidic aqueous solutions of H2SO4 over finely dispersed active carbon particles was studied in a vigorously stirred batch reactor. Molecular oxygen was used as the oxidation agent and several catalysts were screened: active carbon, active carbon impregnated with Pt, Rh, Pd and Ru. Both active carbon and noble metal-active carbon catalysts enhanced the oxidation rate considerably. The order of the noble metals according to the effect was: Pt >> Rh > Pd, Ru. By the use of catalysts, the production capacities of existing oxidation units can be considerably increased. Good coagulants have a high charge on a long polymer chain effectively capturing dirty particles of the opposite charge. Analysis of the reaction product indicated that it is possible to obtain polymeric iron-based products with good coagulation properties. Systematic kinetic experiments were carried out at the temperature and pressure ranges of 60B100°C and 4B10 bar, respectively. The results revealed that both non-catalytic and catalytic oxidation of Fe2+ to Fe3+ take place simultaneously. The experimental data were fitted to rate equations, which were based on a plausible reaction mechanism: adsorption of dissolved oxygen on active carbon, electron transfer from Fe2+ ions to adsorbed oxygen and formation of surface hydroxyls. A comparison of the Fe2+ concentrations predicted by the kinetic model with the experimentally observed concentrations indicated that the mechanistic rate equations were able to describe the intrinsic oxidation kinetics of Fe2+ over active carbon and active carbon-noble metal catalysts. Engineering aspects were closely considered and effort was directed to utilizing existing equipment in the production of the new coagulant. Ferrous sulphate can be catalytically oxidized to produce a novel long-chained polymeric iron-based flocculent in an easy and affordable way in existing facilities. The results can be used for modelling the reactors and for scale-up. Ferric iron (Fe3+) was successfully applied for the dissolution of sphalerite. Sphalerite contains indium, gallium and germanium, among others, and the application can promote their recovery. The understanding of the reduction process of ferric to ferrous iron can be used to develop further the understanding of the dissolution mechanisms and oxidation of ferrous sulphate. Indium, gallium and germanium face an ever-increasing demand in the electronics industry, among others. The supply is, however, very limited. The fact that most part of the material is obtained through secondary production means that real production quota depends on the primary material production. This also sets the pricing. The primary production material is in most cases zinc and aluminium. Recycling of scrap material and the utilization of industrial waste, containing indium, gallium and geranium, is a necessity without real options. As a part of this study plausible methods for the recovery of indium, gallium and germanium have been studied. The results were encouraging and provided information about the precipitation of these valuables from highly acidic solutions. Indium and gallium were separated from acidic sulphuric acid solutions by precipitation with basic sulphates such as alunite or they were precipitated as basic sulphates of their own as galliunite and indiunite. Germanium may precipitate as a basic sulphate of a mixed composition. The precipitation is rapid and the selectivity is good. When the solutions contain both indium and gallium then the results show that gallium should be separated before indium to achieve a better selectivity. Germanium was separated from highly acidic sulphuric acid solutions containing other metals as well by precipitating with tannic acid. This is a highly selective method. According to the study other commonly found metals in the solution do not affect germanium precipitation. The reduction of ferric iron to ferrous, the precipitation of indium, gallium and germanium, and the dissolution of the raw materials are strongly depending on temperature and pH. The temperature and pH effect were studied and which contributed to the understanding and design of the different process steps. Increased temperature and reduced pH improve the reduction rate. Finally, the gained understanding in the studied areas can be employed to develop better industrial processes not only on a large scale but also increasingly on a smaller scale. The small amounts of indium, gallium and germanium may favour smaller and more locally bound recovery.

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Strenx® 960 MC is a direct quenched type of Ultra High Strength Steel (UHSS) with low carbon content. Although this material combines high strength and good ductility, it is highly sensitive towards fabrication processes. The presence of stress concentration due to structural discontinuity or notch will highlight the role of these fabrication effects on the deformation capacity of the material. Due to this, a series of tensile tests are done on both pure base material (BM) and when it has been subjected to Heat Input (HI) and Cold Forming (CF). The surface of the material was dressed by laser beam with a certain speed to study the effect of HI while the CF is done by bending the specimen to a certain angle prior to tensile test. The generated results illustrate the impact of these processes on the deformation capacity of the material, specially, when the material has HI experience due to welding or similar processes. In order to compare the results with those of numerical simulation, LS-DYNA explicit commercial package has been utilized. The generated results show an acceptable agreement between experimental and numerical simulation outcomes.

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The purpose of this thesis is to find out how outbound logistics process can be improved by reducing unnecessary waste in a globally dispersed make-to-order (MTO) supply chain. The research problem was addressed by a multinational corporation that aims to find a solution for reducing unnecessary waste in their outbound logistics process. The focus is on customized products that are delivered via sea transportation. Theoretical framework for improving outbound logistics processes in globally dispersed MTO supply chain was created based on business process management, Porter’s value chain theory, value stream mapping and current reality tree. The empirical research was conducted by using constructive approach due to its ability to research a practical problem and to improve the existing practices. The data was collected from ten semi-structured interviews and three non-participant observations. By analysing the data and applying the theoretical framework, five types of waste were detected in the process that were seen to derive from six root causes. Practical solution was constructed to reduce the waste in the process by combining the existing literature with the ideas raising from empirical data. The results of this thesis suggest that a MNC with a globally dispersed MTO supply chain can improve its outbound logistics process by applying activities that enhance internal and external integration, collaboration and coordination, and increase predictability of the process. This research has practical relevance both for the case company as well as for other MNCs with globally dispersed MTO supply chains that aim to improve their outbound logistics processes. This research contributes to the BPM and CRA research by providing an evidence for their applicability in the new context.

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For the past decades, educational large-scale reforms have been elaborated and implemented in many countries and often resulted in partial or complete failure. These results brought researchers to study policy processes in order to address this particular challenge. Studies on implementation processes brought to light an existing causal relationship between the implementation process and the effectiveness of a reform. This study aims to describe the implementation process of educational change in Finland, who produced efficient educational reforms over the last 50 years. The case study used for the purpose of this study is the national reform of undivided basic education (yhtenäinen peruskoulu) implemented in the end of the 1990s. Therefore, this research aims to describe how the Finnish undivided basic education reform was implemented. This research was carried out using a pluralist and structuralist approach of policy process and was analyzed according to the hybrid model of implementation process. The data were collected using a triangulation of methods, i.e. documentary research, interviews and questionnaires. The data were qualitative and were analyzed using content analysis methods. This study concludes that the undivided basic education reform was applied in a very decentralized manner, which is a reflection of the decentralized system present in Finland. Central authorities provided a clear vision of the purpose of the reform, but did not control the implementation process. They rather provided extensive support in the form of transmission of information and development of collaborative networks. Local authorities had complete autonomy in terms of decision-making and implementation process. Discussions, debates and decisions regarding implementation processes took place at the local level and included the participation of all actors present on the field. Implementation methods differ from a region to another, with is the consequence of the variation of the level of commitment of local actors but also the diversity of local realities. The reform was implemented according to existing structures and values, which means that it was in cohesion with the context in which it was implemented. These results cannot be generalized to all implementation processes of educational change in Finland but give a great insight of what could be the model used in Finland. Future studies could intent to confirm the model described here by studying other reforms that took place in Finland.

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For the past decades, educational large-scale reforms have been elaborated and implemented in many countries and often resulted in partial or complete failure. These results brought researchers to study policy processes in order to address this particular challenge. Studies on implementation processes brought to light an existing causal relationship between the implementation process and the effectiveness of a reform. This study aims to describe the implementation process of educational change in Finland, who produced efficient educational reforms over the last 50 years. The case study used for the purpose of this study is the national reform of undivided basic education (yhtenäinen peruskoulu) implemented in the end of the 1990s. Therefore, this research aims to describe how the Finnish undivided basic education reform was implemented. This research was carried out using a pluralist and structuralist approach of policy process and was analyzed according to the hybrid model of implementation process. The data were collected using a triangulation of methods, i.e. documentary research, interviews and questionnaires. The data were qualitative and were analyzed using content analysis methods. This study concludes that the undivided basic education reform was applied in a very decentralized manner, which is a reflection of the decentralized system present in Finland. Central authorities provided a clear vision of the purpose of the reform, but did not control the implementation process. They rather provided extensive support in the form of transmission of information and development of collaborative networks. Local authorities had complete autonomy in terms of decision-making and implementation process. Discussions, debates and decisions regarding implementation processes took place at the local level and included the participation of all actors present on the field. Implementation methods differ from a region to another, with is the consequence of the variation of the level of commitment of local actors but also the diversity of local realities. The reform was implemented according to existing structures and values, which means that it was in cohesion with the context in which it was implemented. These results cannot be generalized to all implementation processes of educational change in Finland but give a great insight of what could be the model used in Finland. Future studies could intent to confirm the model described here by studying other reforms that took place in Finland.

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This study is motivated by the question how resource scarce innovative entrepreneurial companies seek and leverage global resources. This study takes a resource-seeking perspective a step forward and suggests that resources that enable the entrepreneurial internationalisation are largely accrued from the early stages of entrepreneurial life; that is from the innovation development. Consequently, this study seeks to explain how innovation and internationalisation processes are interrelated in the entrepreneurial internationalisation. This main objective is approached through three research questions, (1) What role do inter-organisational relationships in innovation have in the entrepreneurial internationalisation process? (2) What kind of inward–outward links do inter-organisational relationships create in the resource-seeking-based entrepreneurial internationalisation process? (3) What kind of capability to collaborate forms in the interaction of inter-organisational relationship deployment? The research design is a mixed methods design that consists of quantitative pilot study and qualitative multiple case study of five entrepreneurial life science companies from Finland and Austria. The findings show that innovation and internationalisation processes are tightly interwoven in pre-internationalisation state. The findings also reveal that the more experienced companies are able to take advantage of complexcross-border inter-organisational relationship structures better than the starting companies. However, very minor evidence was found on inward links translating into outward links in the entrepreneurial internationalisation process, despite the expectation to observe more of these links in the data. Combined intangible-tangible resource-seeking was the most preferred to build links between inward–outward internationalisation but also to develop competence to collaborate. By adopting a resource- instead of market-seeking approach, this study illustrated that internationalisation extends to early stages of innovative companies, and that in high-technology companies’ potentially significant cross-border relationships have started to form long before incorporation. Therefore, these observations justified the firmer inclusion of pre-company history in innovative entrepreneurship studies. The study offers a conceptualisation of entrepreneurial internationalisation that is perceived as a process. The main theoretical contributions are in the areas of international entrepreneurship and in the behavioural process studies of entrepreneurial internationalisation and resource-based internationalisation. The inclusion of the innovation-based discussion, namely the innovation process, in the internationalisation process theories has clearly contributed to the understanding of entrepreneurial internationalisation in the context of international entrepreneurship. Innovation development is a central act of entrepreneurial companies, and neglecting innovation process investigation from entrepreneurial internationalisation leaves potentially influential mechanisms unexplored.

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The purpose of this study is to find out how laser based Directed Energy Deposition processes can benefit from different types of monitoring. DED is a type of additive manufacturing process, where parts are manufactured in layers by using metallic powder or metallic wire. DED processes can be used to manufacture parts that are not possible to manufacture with conventional manufacturing processes, when adding new geometries to existing parts or when wanting to minimize the scrap material that would result from machining the part. The aim of this study is to find out why laser based DED-processes are monitored, how they are monitored and what devices are used for monitoring. This study has been done in the form of a literature review. During the manufacturing process, the DED-process is highly sensitive to different disturbances such as fluctuations in laser absorption, powder feed rate, temperature, humidity or the reflectivity of the melt pool. These fluctuations can cause fluctuations in the size of the melt pool or its temperature. The variations in the size of the melt pool have an effect on the thickness of individual layers, which have a direct impact on the final surface quality and dimensional accuracy of the parts. By collecting data from these fluctuations and adjusting the laser power in real-time, the size of the melt pool and its temperature can be kept within a specified range that leads to significant improvements in the manufacturing quality. The main areas of monitoring can be divided into the monitoring of the powder feed rate, the temperature of the melt pool, the height of the melt pool and the geometry of the melt pool. Monitoring the powder feed rate is important when depositing different material compositions. Monitoring the temperature of the melt pool can give information about the microstructure and mechanical properties of the part. Monitoring the height and the geometry of the melt pool is an important factor in achieving the desired dimensional accuracy of the part. By combining multiple different monitoring devices, the amount of fluctuations that can be controlled will be increased. In addition, by combining additive manufacturing with machining, the benefits of both processes could be utilized.

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Fokuserande händelser är plötsliga, ovanliga och för med sig negativa konsekvenser för ett stort antal människor. Det handlar om det vi i vardagligt tal kallar kriser och katastrofer. En intensiv medierapportering i kombination med oroade medborgare gör att kriser och katastrofer är viktiga samhällspåfrestningar som beslutsfattare måste hantera. Syftet med avhandlingen är att öka förståelsen för hur fokuserande händelser påverkar samhälleliga processer. Avhandlingens två övergripande forskningsfrågor tar fasta på jämförelsen av olika typer av fokuserande händelser. För det första, skillnader i hur naturkatastrofer och katastrofer som tillkommit genom mänskligt handlade påverkar samhället, och för det andra, hur händelser med olika stark fokuseringskraft påverkar samhället. Medborgarreaktioner studeras i en experimentell laboratoriestudie, den mediala rapporteringen analyseras genom kvantitativ innehållsanalys av texter och bilder, och på den parlamentariska arenan analyseras riksdagsdebatten genom kvantitativ innehållsanalys. De temaområden som identifieras i den teoretiska referensramen ligger till grund för analysen och tar fasta på de känslor som händelsen ger upphov till, hur händelsen kontextualiseras (framing), skuldbeläggning samt möjliga lösningar som förs fram. Resultatet från studierna visar att skillnader mellan olika typer av händelser syns tydligast hos medborgare, uttryckt genom starkare emotionella reaktioner för händelser med stark fokusering, och på den mediala arenan, genom mer utrymme för dessa händelser. Då kriser och katastrofer med olika stark fokuseringskraft når riksdagen får de däremot ett relativt likadant mottagande. I jämförelsen mellan naturkatastrofer och människoskapade händelser visar resultaten att naturkatastrofer ofta diskuteras som specifika händelser, medan människoskapade händelser placeras i en bredare samhällelig kontext och diskuteras under längre tid. Avhandlingen bidrar till diskussionen om hur våra känslor och vår kognition samspelar i krissituationer. De omedvetna signaler som vår kropp ger oss gällande hur vi ska reagera på en farlig situation kan påverka om vi är rädda, oroliga eller till och med positivt inställda. I ljuset av de tre studierna är det tydligt att de emotionella reaktionerna minskar ju högre upp i den politiska processen vi kommer. Trots att medborgare och medier reagerar starkt är de emotionella reaktionerna på den politiska arenan relativt milda och skuldbeläggningen näst intill icke-existerande.

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This study discusses the interactions of different decision-making mechanisms in the process of change of a successful entrepreneurial dairy firm in Vietnam. The purpose of the study is to construct a theoretical framework, which explains the interactions between effectual and causal decision-making processes in different phases of business, and to provide a real life example with practical recommendations for entrepreneurs and managers. In order to achieve this purpose, a preliminary theoretical framework was built, using process theories applied to different decision making modes, referred to as causation and effectuation. The case was studied through ethnographic research method, with three semi-structured interviews, one unstructured interview, secondary data and observations within four months in 2013-2014. After the data was analyzed, a modified framework was drawn from the result. The finding of this study shows that there was an interaction between effectual and causal decision-making processes in different stages of the company’s development. The entrepreneur applied effectual decision-making process to develop a unique business model and a new dairy market segment. However, when a new market demand arose, the company’s resources became insufficient, they thus had to shift to causation process to adapt to market change. Simultaneously, with better-accumulated resources, the entrepreneur continued the effectuation process to create another brand new dairy market segment. This study, thus, contributes to effectuation theory, emphasizing the necessity of combining effectual and causal decision-making processes in different phases of business. It is suggested that business would develop with an effectual process until a business model is viable for growth. It continues to use this process up to a certain degree. When the market changes, the company needs to collect more means to adapt to the changes. They need to set new goals and this is a shift to the use of causal process, which builds on prediction. It uses goals and teleology as driving mechanisms and tries to exploit and fill potential resource gaps to achieve these goals. At the same time, there are new iterations that look to establish new lines or types of business with the given means, which are now well established. This again employs effectual mechanisms, which are based on evolutionary process, until they reach the stage of viable tested business model. Moreover, this study hopes to provide know-how to entrepreneurs and managers of small companies in similar situations, suggesting how to combine effectual and causal decision-making processes to deal with various circumstances in different times.