981 resultados para university studies
Resumo:
In the theoretical part, the different polymerisation catalysts are introduced and the phenomena related to mixing in the stirred tank reactor are presented. Also the advantages and challenges related to scale-up are discussed. The aim of the applied part was to design and implement an intermediate-sized reactor useful for scale-up studies. The reactor setting was tested making one batch of Ziegler–Natta polypropylene catalyst. The catalyst preparation with a designed equipment setting succeeded and the catalyst was analysed. The analyses of the catalyst were done, because the properties of the catalyst were compared to the normal properties of Ziegler–Natta polypropylene catalyst. The total titanium content of the catalyst was slightly higher than in normal Ziegler–Natta polypropylene catalyst, but the magnesium and aluminium content of the catalyst were in the normal level. By adjusting the siphonation tube and adding one washing step the titanium content of the catalyst could be decreased. The particle size of the catalyst was small, but the activity was in a normal range. The size of the catalyst particles could be increased by decreasing the stirring speed. During the test run, it was noticed that some improvements for the designed equipment setting could be done. For example more valves for the chemical feed line need to be added to ensure inert conditions during the catalyst preparation. Also nitrogen for the reactor needs to separate from other nitrogen line. With this change the pressure in the reactor can be kept as desired during the catalyst preparation. The proposals for improvements are presented in the applied part. After these improvements are done, the equipment setting is ready for start-up. The computational fluid dynamics model for the designed reactor was provided by cooperation with Lappeenranta University of Technology. The experiments showed that for adequate mixing with one impeller, stirring speed of 600 rpm is needed. The computational fluid dynamics model with two impellers showed that there was no difference in the mixing efficiency if the upper impeller were pumping downwards or upwards.
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The purpose of this study is to deepen the understanding of the meaning of ownership in the context of small and medium sized businesses. The research on ownership has increased and widened during the last few years. Ownership is treated increasingly as a psychological phenomenon and it has been noticed that it is common for SME ownermanagers to be mentally linked to their firms. Previous research is suggesting that the central role of an owner-manager in an SME is specifying the concept of SMEs, and that ownership is creating a great heterogeneity within SMEs. This study suggests that there is a variation whitin ownership behaviour of small business owners, and the variation is not totally random or irrational, but following the general patterns of business ownership and of doing business on an SME level. This study is a concept analytical in nature and it builds on the theoretical clarification of the concept of ownership. The theoretical consideration concludes with proposing a definition of ownership: Ownership means a subject’s relatively sustaining position of control in regard to an object. The empirical part of this study consists of five articles, out of which one is conceptual and four are empirical in nature. The notion of contextuality of ownership and the notions of SME characteristics form the basic premise of this study and the theoretical basis for the publications. From the owner-managers point of view, ownership relates the owner also to his or her environment and therefore also to the valuations of the owner-managers. This means that all the dimensions are not equally valued, but certain dimensions in his or her ownership are more important. The presented empirical research is supporting the claim that there is a variation whitin ownership behaviour of small business owners. When bringing the definition of ownership onto a personal and psychological level and into the SME context, it was noticed that ownership is not only a closed system phenomenon occurring between the owner and object owned, but it is also elementarily connected to the environment. Ownership - along with the psychological side of it - is a contextual phenomenon where the fundamental factor is the relatively sustaining position of control with regard to an object. As a contribution of the study, this definition is bringing a new point of view to the discussion on SMEs, SME strategic behaviour and family businesses. The study concludes with pointing out directions for future research.
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Previous studies of the local involvement of multinational corporation (MNC) subsidiaries focus on host-country firms and local business partners such as suppliers and customers. The role of host-country universities in the same context of innovation networks is neglected. Furthermore, there are many organizational culture- and knowledge-related differences between universities and companies, and this is likely to pose additional challenges for successful collaboration. Early university-industry (U-I) studies have primarily been limited within a national boundary, being concerned with a single level of culture (i.e., at an organizational level) and one-way knowledge transfer from university to industry. Research on more dynamic knowledge interaction in multinational settings is lacking. This is particularly true in the business context of China. In today’s globalizing and rapidly changing organizations, addressing cultural differences and clashes is an everyday reality, and inter-cultural U-I collaboration is becoming a key asset for gaining global competitiveness. This study deals with Finnish MNC subsidiaries’ research collaboration with Chinese universities. It aims to explore the essence of such U-I collaboration and knowledge interaction, uncovering the deep functioning mechanisms of culture underlying effective collaborative knowledge creation and innovation. The study reviews critically different bodies of literature including knowledge management theories and studies, U-I collaboration and knowledge interaction, and cross-cultural research in terms of organizational knowledge generation and utilization. It adopts a case study strategy with qualitative research methods, and data is collected through in-depth interviews and participant observation. The study presents the following major findings: 1. In the light of a comprehensive analysis of U-I collaboration, an effective matching strategy is proposed, in the assumption that good alignment of knowledge interaction strategies and approaches with their corresponding knowledge type, capability development and research task may greatly enhance the effectiveness of cross-cultural U-I collaboration and knowledge interaction. 2. It is proposed that in the Chinese MNC context more dynamic types of knowledge interaction like knowledge co-creation should be of key concern particularly when dealing simultaneously with multi-disciplinary applied research of human factors and technologies. U-I knowledge interaction, otherwise, pays attention only to the study of one-way technology and knowledge transfer. 3. It is posited that the influence of culture on collaborative knowledge interaction can be studied in a valuable way when knowledge-related variables are simultaneously taken into account. A systematic analysis of the role of knowledge in cross-cultural knowledge interaction could best be approached from multi-aspects of knowledge including not only nature, characteristics and types of knowledge but also the process of knowledge (e.g., intensifications of knowledge interaction). 4. The study demonstrates the significant role of aspects of the host-country culture (e.g., Chinese guanxi) in U-I collaboration and knowledge interaction. This is evident, for instance, in issues related to interpersonal relationships and trust, true interest and the relatedness of the research, mutual commitment and learning, communication intensity and interaction, and awareness of cultural and knowledge-related differences between collaboration partners. Theoretical and practical implications of the findings are suggested and discussed.
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Previous studies on pencil grip have typically dealt with the developmental aspects in young children while handwriting research is mainly concerned with speed and legibility. Studies linking these areas are few. Evaluation of the existing pencil grip studies is hampered by methodological inconsistencies. The operational definitions of pencil grip arerational but tend to be oversimplified while detailed descriptors tend to be impractical due to their multiplicity. The present study introduces a descriptive two-dimensional model for the categorisation of pencil grip suitable for research applications in a classroom setting. The model is used in four empirical studies of children during the first six years of writing instruction. Study 1 describes the pencil grips observed in a large group of pupils in Finland (n = 504). The results indicate that in Finland the majority of grips resemble the traditional dynamic tripod grip. Significant genderrelated differences in pencil grip were observed. Study 2 is a longitudinal exploration of grip stability vs. change (n = 117). Both expected and unexpected changes were observed in about 25 per cent of the children's grips over four years. A new finding emerged using the present model for categorisation: whereas pencil grips would change, either in terms of ease of grip manipulation or grip configuration, no instances were found where a grip would have changed concurrently on both dimensions. Study 3 is a cross-cultural comparison of grips observed in Finland and the USA (n = 793). The distribution of the pencil grips observed in the American pupils was significantly different from those found in Finland. The cross-cultural disparity is most likely related to the differences in the onset of writing instruction. The differences between the boys' and girls' grips in the American group were non-significant.An implication of Studies 2 and 3 is that the initial pencil grip is of foremost importance since pencil grips are largely stable over time. Study 4 connects the pencil grips to assessment of the mechanics of writing (n = 61). It seems that certain previously not recommended pencil grips might nevertheless be includedamong those accepted since they did not appear to hamper either fluency or legibility.
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I undersökningen tillämpas Charles Sanders Peirces semiotik för en kritisk granskning av arkeologiska tolkningsprocesser. Enligt Peirce bygger all betydelsegivning på tecken, som kan vara teckningar, föremål, ord, byggkonstruktioner eller egentligen vad som helst. Ett tecken är tredimensionellt: ”objekt”, ”tecken” och ”tolkning”. I sina tidiga skrifter definierar han tre grundtyper för tecknet, Index, Icon och Symbol. De grundläggande definitionerna i Peirces semiotik blir till ett slags lins. När den placeras på skrifter av en arkeolog som uttolkar tecken, framträder deras inre uppbyggnad, motiveringar och logiska konsekvens klart. Att beakta är, att denna bok är lika lite avsedd att utgöra en systematisk klarläggning av den arkeologiska semiotiken, som en omfattande beskrivning av symboliken i det neolitiska Mellanöstern. Analysen är deskriptiv och inte avsedd att utvärdera tolkningarnas riktighet, utan enbart att klarlägga hur arkeologen kommit fram till dessa. Som objekt har valts neolitiska södra Levanten, där viktiga fynd gällande denna i mänsklighetens kulturhistoria så betydelsefulla skede har gjorts. Förhistorien är intressant med tanke på arkeologisk semiosis, eftersom uttolkaren av en symbol inte kan stöda sig på textfynd, utan måste på annat sätt upptäcka vad ett föremål eller en byggnad betytt för sin upphovsman. Att upptäcka en trovärdig betydelse är ofta en mycket svår och understundom rentav omöjlig uppgift. Efter att förhållandet mellan semiotik och arkeologi dryftats analyseras i boken John Garstangs och Kathleen M. Kenyons grundläggande tolkningar i Jeriko, Denise-Schmandt Besserats jämförande analyser för uttolkningen av \'Ain Ghazalis kranium, Michele A. Millers kontextuella analys i Jarmuk samt David Lewis-Williams’ starkt strukturalistiska analys av betydelsen av fynden i \'Ain Ghazal. Peirces semiotik har använts som stöd för arkeologin i mycket mindre utsträckning än F. de Saussures lingvistiska ja strukturalistiska semiotik. I Mellanöstern har man hittills inte alls gjort det. Ingen av de forskare som behandlas i boken hänvisar själv till semiotik eller tecken. Logiken i uttolkningen av dessa undersökningar är mycket invecklad, och de av Peirce gestaltade processerna för betydelsegivning visar sig härvidlag utgöra en ytterst klargörande kritisk apparat.
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Longitudinal studies are quite rare in the area of Operations Management. One reason might be the time needed to conduct such studies, and then the lack of experience and real-life examples and results. The aim of the thesis is to examine longitudinal studies in the area of OM and the possible advantages, challenges and pitfalls of such studies. A longitudinal benchmarking study, Made in Finland, was analyzed in terms of the study methodology and its outcomes. The timeline of this longitudinal study is interesting. The first study was made in 1993, the second in 2004 and the third in 2010. Between these studies some major changes occurred in the Finnish business environment. Between the first and second studies, Finland joined the ETA and the EU, and globalization started with the rise of the Internet era, while between the second and third studies financial turmoil started in 2007. The sample and cases used in this study were originally 23 manufacturing sites in Finland. These sites were interviewed in 1993, in 2004 and 2010. One important and interesting aspect is that all the original sites participated in 2004, and 19 sites were still able to participate in 2010. Four sites had been closed and/or moved abroad. All of this gave a good opportunity to study the changes that occurred in the Finnish manufacturing sites and their environment, and how they reacted to these changes, and the effects on their performance. It is very seldom, if ever, that the same manufacturing sites have been studied in a longitudinal setting by using three data points. The results of this study are thus unique, and the experience gained is valuable for practitioners.
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Nordic forum for nursing teachers. Wednesday - Friday 9-11 November 2011 Ounasvaara Campus School of Heath Care and Sports Rovaniemi University of Applied Sciences
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This thesis presents an experimental study and numerical study, based on the discrete element method (DEM), of bell-less charging in the blast furnace. The numerical models are based on the microscopic interaction between the particles in the blast furnace charging process. The emphasis is put on model validation, investigating several phenomena in the charging process, and on finding factors that influence the results. The study considers and simulates size segregation in the hopper discharging process, particle flow and behavior on the chute, which is the key equipment in the charging system, using mono-size spherical particles, multi-size spheres and nonspherical particles. The behavior of the particles at the burden surface and pellet percolation into a coke layer is also studied. Small-scale experiments are used to validate the DEM models.
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This thesis is based on computational chemistry studies on lignans, focusing on the naturally occurring lignan hydroxymatairesinol (HMR) (Papers I II) and on TADDOL-like conidendrin-based chiral 1,4-diol ligands (LIGNOLs) (Papers III V). A complete quantum chemical conformational analysis on HMR was previously conducted by Dr. Antti Taskinen. In the works reported in this thesis, HMR was further studied by classical molecular dynamics (MD) simulations in aqueous solution including torsional angle analysis, quantum chemical solvation e ect study by the COnductorlike Screening MOdel (COSMO), and hydrogen bond analysis (Paper I), as well as from a catalytic point of view including protonation and deprotonation studies at di erent levels of theory (Paper II). The computational LIGNOL studies in this thesis constitute a multi-level deterministic structural optimization of the following molecules: 1,1-diphenyl (2Ph), two diastereomers of 1,1,4-triphenyl (3PhR, 3PhS), 1,1,4,4-tetraphenyl (4Ph) and 1,1,4,4-tetramethyl (4Met) 1,4-diol (Paper IV) and a conformational solvation study applying MD and COSMO (Paper V). Furthermore, a computational study on hemiketals in connection with problems in the experimental work by Docent Patrik Eklund's group synthesizing the LIGNOLs based on natural products starting from HMR, is shortly described (Paper III).
Resumo:
The aim of this thesis research was to gain a better understanding of the emplacement of rapakivi granite intrusions, as well as the emplacement of gold-bearing hydrothermal fluids in structurally controlled mineralizations. Based on investigations of the magnetic fabric, the internal structures could be analysed and the intrusion mechanisms for rapakivi granite intrusions and respectively different deformation stages within gold-bearing shear and fault zones identified. Aeromagnetic images revealed circular structures within the rapakivi granite batholiths of Wiborg, Vehmaa and Åland. These circular structures represent intrusions that eventually build up these large batholiths. The rapakivi granite intrusions of Vehmaa, Ruotsinpyhtää within the Wiborg batholith and Saltvik intrusions within the Åland batholith all show bimodal magnetic susceptibilities with paramagnetic and ferromagnetic components. The distribution of the bimodality is related to different magma batches of the studied intrusions. The anisotropy of magnetic susceptibility (AMS) reveals internal structures that cannot be studied macroscopically or by microscope. The Ruotsinpyhtää and Vehmaa intrusions represent similar intrusion geometries, with gently to moderately outward dipping magnetic foliations. In the case of Vehmaa, the magnetic lineations are gently plunging and trend in the directions of the slightly elongated intrusion. The magnetic lineations represent magma flow. The shapes of the AMS ellipsoids are also more planar (oblate) in the central part of the intrusion, whereas they become more linear (prolate) near the margin. These AMS results, together with field observations, indicate that the main intrusion mechanism has involved the subsidence of older blocks with successive intrusion of fractionated magma during repeated cauldron subsidence. The Saltvik area within the Åland batholith consists of a number of smaller elliptical intrusions of different rapakivi types forming a multiple intrusive complex. The magnetic fabric shows a general westward dipping of the pyterlite and eastward dipping of the contiguous even-grained rapakivi granite, which indicates a central inflow of magma batches towards the east and west resulting from a laccolitic emplacement of magma batches, while the main mechanism for space creation was derived from subsidence. The magnetic fabric of structurally controlled gold potential shear and fault zones in Jokisivu, Satulinmäki and Koijärvi was investigated in order to describe the internal structures and define the deformation history and emplacement of hydrothermal fluids. A further aim of the research was to combine AMS studies with palaeomagnetic methods to constrain the timing for the shearing event relative to the precipitation of ferromagnetic minerals and gold. All of the studied formations are dominated by monoclinic pyrrhotite. The AMS directions generally follow the tectonic structures within the formations. However, internal variations in the AMS direction as well as the shapes of the AMS ellipsoids are observed within the shear zones. In Jokisivu and Satulinmäki in particular, the magnetic signatures of the shear zone core differ from the margins. Furthermore, the shape of the magnetic fabric in the shear zone core of Jokisivu is dominated by oblate shapes, whereas the margins exhibit prolate shapes. These variations indicate a later effect of the hydrothermal fluids on the general shear event. The palaeo-magnetic results reveal a deflection from the original Svecofennian age geomagnetic direction. These results, coupled with correlations between the orientation of the NRM vectors and the magnetic and rock fabrics, imply that the gold-rich hydrothermal fluids were emplaced pre/syntectonically during the late stages of the Svecofennian orogeny.
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This study combines several projects related to the flows in vessels with complex shapes representing different chemical apparata. Three major cases were studied. The first one is a two-phase plate reactor with a complex structure of intersecting micro channels engraved on one plate which is covered by another plain plate. The second case is a tubular microreactor, consisting of two subcases. The first subcase is a multi-channel two-component commercial micromixer (slit interdigital) used to mix two liquid reagents before they enter the reactor. The second subcase is a micro-tube, where the distribution of the heat generated by the reaction was studied. The third case is a conventionally packed column. However, flow, reactions or mass transfer were not modeled. Instead, the research focused on how to describe mathematically the realistic geometry of the column packing, which is rather random and can not be created using conventional computeraided design or engineering (CAD/CAE) methods. Several modeling approaches were used to describe the performance of the processes in the considered vessels. Computational fluid dynamics (CFD) was used to describe the details of the flow in the plate microreactor and micromixer. A space-averaged mass transfer model based on Fick’s law was used to describe the exchange of the species through the gas-liquid interface in the microreactor. This model utilized data, namely the values of the interfacial area, obtained by the corresponding CFD model. A common heat transfer model was used to find the heat distribution in the micro-tube. To generate the column packing, an additional multibody dynamic model was implemented. Auxiliary simulation was carried out to determine the position and orientation of every packing element in the column. This data was then exported into a CAD system to generate desirable geometry, which could further be used for CFD simulations. The results demonstrated that the CFD model of the microreactor could predict the flow pattern well enough and agreed with experiments. The mass transfer model allowed to estimate the mass transfer coefficient. Modeling for the second case showed that the flow in the micromixer and the heat transfer in the tube could be excluded from the larger model which describes the chemical kinetics in the reactor. Results of the third case demonstrated that the auxiliary simulation could successfully generate complex random packing not only for the column but also for other similar cases.
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The main objective of this doctoral dissertation is to reach a holistic and indepth understanding of the intercultural interaction within dyadic business relationships through the perspective of individual managers. The empirical setting is dyadic business relationships between Russian and Finnish firms in construction and engineering industries. The motivation for the study mainly arose from: 1) the lack of business marketing literature considering cultural and individual perspectives; 2) the need to find ways to study intercultural issues in business relationships, other than through the application of models derived from the work of Hofstede (1980). The study consists of two parts, an introductory essay containing the research objectives, theoretical foundations, methodological choices, limitations and contributions, and original research articles. The four articles each address a sub-objective: 1) to develop an understanding of intercultural business relationships development, cultural adaptation, and its role in the development of trust (Article 1); 2) to develop an appropriate methodological framework for studying business interaction from a cultural and individual perspective (Article 2); 3) to develop an understanding of the role of culture in individual manager’s sensemaking of interaction events in business relationships (Article 3); and 4) to develop an appropriate theoretical framework for studying interactive intercultural business relationships in international industrial markets (Article 4). The ontological and epistemological foundations are built on the interpretivist/ social constructivist view of reality. Interaction, in this study, is seen as being conducted between individuals, who are the key representative actors of their firms. In turn, culture is regarded both as an independent context existing prior to the individuals’ participation in it, and as knowledge incorporated by the individuals, who use it in sensemaking and interaction across cultures. The methods applied in the articles are: an interpretive qualitative study (Article 1), a literature review and conceptual analysis (Article 2), a structural analysis of the narratives and a metaphor analysis (Article 3), and a literature review and conceptual analysis (Article 4). The main contributions are the following. First, it contributes to business marketing literature by developing the theoretical, conceptual, and methodological underpinning of IMP theories in relation to culture. Second, the thesis contributes to the growing literature on managerial sensemaking in industrial markets by looking at it from a cultural perspective, as well as emphasizing the importance of figurative language in cultural sensemaking.