991 resultados para Starting Process


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The existing models describing electrochemical phase formation involving both adsorption and a nucleation/growth process are modified. The limiting cases leading to the existing models are discussed. The characteristic features of the potentiostatic transients are presented. A generalization of the Avrami ansatz is given for two or more competitive irreversibly growing phases.

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Stochastic behavior of an aero-engine failure/repair process has been analyzed from a Bayesian perspective. Number of failures/repairs in the component-sockets of this multi-component system are assumed to follow independent renewal processes with Weibull inter-arrival times. Based on the field failure/repair data of a large number of such engines and independent Gamma priors on the scale parameters and log-concave priors on the shape parameters, an exact method of sampling from the resulting posterior distributions of the parameters has been proposed. These generated parameter values are next utilised in obtaining the posteriors of the expected number of system repairs, system failure rate, and the conditional intensity function, which are computed using a recursive formula.

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A computer code is developed as a part of an ongoing project on computer aided process modelling of forging operation, to simulate heat transfer in a die-billet system. The code developed on a stage-by-stage technique is based on an Alternating Direction Implicit scheme. The experimentally validated code is used to study the effect of process specifics such as preheat die temperature, machine ascent time, rate of deformation, and dwell time on the thermal characteristics in a batch coining operation where deformation is restricted to surface level only.

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A bi-level voltage drive circuit for step motors that can provide the required high starting torque is described. In this circuit, microprocessor 8085 and parallel port interface 8255 are used for generating the code sequence. The inverter buffer 74LS06 provides enough drive to a darlington pair transistor. The comparator LM339 is used to compare the required voltage for step motor with the set value. This circuit can be effectively used for step motors having maximum rated current of less than 15 A with proper heat sink.

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International new ventures (INVs) are firms that engage very early after their foundation, if not immediately, in inter-national activities. INVs are a relatively recent phenomenon that deviates from earlier theories on international business. In order to develop our understanding of the emergence and early internationalisation of INVs three different research areas are built upon in the dissertation: International Entrepreneurship, Entrepreneurship and Networks. Net-works have been identified as important for INVs. However, there is a lack of more profound studies regarding the way different types of relationships influence INVs. Few studies are concerned with exploration and exploitation of opportunities and research on the benefits and drawbacks of entrepreneurs’ relationships for the international opportunity recognition process has been called for. By taking a network approach to opportunity exploration and exploitation, the dissertation develops our under-standing of how entrepreneurs’ relationships are involved in exploring and exploiting opportunities during an INV’s early and critical entrepreneurial and internationalisation events. The critical events are studied during three phases: pre-founding, start-up and early internationalisation. Since internationalisation is present from the very beginning, the early internationalisation phase may be parallel to both the pre-founding and the start-up phase. The dissertation contributes to international entrepreneur-ship research in mainly two ways. First, by offering a deep insight into which opportunity exploration and exploitation activities entrepreneurs’ relationships are involved. Second, by adding to our understanding of what the relationships contribute to these activities, mainly in the sense of benefits gained through the relationships. Studying micro firms in real time in their early development towards INVs is considered a unique contribution of the study as it offers valuable insights into pre-founding, start-up, pre-internationalisation as well as early internationalisation. The study shows that in order to understand the development of INVs, it is beneficial to go back to times when there was no thought of starting the INV. By focusing on the entrepreneurs’ background and relationships a more complete picture of the INV is gained. Relationships created at former workplaces or during school time might be the ones that develop business opportunities and set off internationalisation. By focusing on the pre-founding phase, the study also contributes to entrepreneurship literature as this stage has often been neglected or assumed obvious in earlier research. This dissertation shows that an important and mostly lengthy pre-founding phase precedes the decision to start a f rm. In addition, the integration of entrepreneurs’ real experiences with existing theory to develop a continuum for the strength of relationships allows for contributions to network theory.

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Gaussian Processes (GPs) are promising Bayesian methods for classification and regression problems. They have also been used for semi-supervised learning tasks. In this paper, we propose a new algorithm for solving semi-supervised binary classification problem using sparse GP regression (GPR) models. It is closely related to semi-supervised learning based on support vector regression (SVR) and maximum margin clustering. The proposed algorithm is simple and easy to implement. It gives a sparse solution directly unlike the SVR based algorithm. Also, the hyperparameters are estimated easily without resorting to expensive cross-validation technique. Use of sparse GPR model helps in making the proposed algorithm scalable. Preliminary results on synthetic and real-world data sets demonstrate the efficacy of the new algorithm.

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The Norrish type II process is examined in three ketones containing primary, secondary and tertiary C---H bonds in the γ position relative to the carbonyl groups; the MINDO/3 semiempirical self-consistent field (SCF) molecular orbital (MO) method was used with complete geometry optimization in the unrestricted Hartree—Fock frame for the open-shell species. Results show that barriers to conformational change in ketones play an important role in the triplet reaction.

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The accompanying collective research report is the result of the research project in 1986­90 between The Finnish Academy and the former Soviet Academy of Sciences. The project was organized around common field work in Finland and in the former Soviet Union and theoretical analyses of tree growth determining processes. Based on theoretical analyses, dynamic stand growth models were made and their parameters were determined utilizing the field results. Annual cycle affects the tree growth. Our theoretical approach was based on adaptation to local climate conditions from Lapland to South Russia. The initiation of growth was described as a simple low and high temperature accumulation driven model. Linking the theoretical model with long term temperature data allowed us to analyze what type of temperature response produced favorable outcome in different climates. Initiation of growth consumes the carbohydrate reserves in plants. We measured the dynamics of insoluble and soluble sugars in the very northern and Karelian conditions. Clear cyclical pattern was observed but the differences between locations were surprisingly small. Analysis of field measurements of CO2 exchange showed that irradiance is the dominating factor causing variation in photosynthetic rate in natural conditions during summer. The effect of other factors is so small that they can be omitted without any considerable loss of accuracy. A special experiment carried out in Hyytiälä showed that the needle living space, defined as the ratio between the shoot cylindric volume and needle surface area, correlates with the shoot photosynthesis. The penetration of irradiance into Scots pine canopy is a complicated phenomenon because of the movement of the sun on the sky and the complicated structure of branches and needles. A moderately simple but balanced forest radiation regime submodel was constructed. It consists of the tree crown and forest structure, the gap probability calculation and the consideration of spatial and temporal variation of radiation inside the forest. The common field excursions in different geographical regions resulted in a lot of experimental data of regularities of woody structures. The water transport seems to be a good common factor to analyse these properties of tree structure. There are evident regressions between cross-sectional areas measured at different locations along the water pathway from fine roots to needles. The observed regressions have clear geographical trends. For example, the same cross-sectional area can support three times higher needle mass in South Russia than in Lapland. Geographical trends can also be seen in shoot and needle structure. Analysis of data published by several Russian authors show, that one ton of needles transpire 42 ton of water a year. This annual amount of transpiration seems to be independent of geographical location, year and site conditions. The produced theoretical and experimental material is utilised in the development of stand growth model that describes the growth and development of Scots pine stands in Finland and the former Soviet Union. The core of the model is carbon and nutrient balances. This means that carbon obtained in photosynthesis is consumed for growth and maintenance and nutrients are taken according to the metabolic needs. The annual photosynthetic production by trees in the stand is determined as a function of irradiance and shading during the active period. The utilisation of the annual photosynthetic production to the growth of different components of trees is based on structural regularities. Since the fundamental metabolic processes are the same in all locations the same growth model structure can be applied in the large range of Scots pine. The annual photosynthetic production and structural regularities determining the allocation of resources have geographical features. The common field measurements enable the application of the model to the analysis of growth and development of stands growing on the five locations of experiments. The model enables the analysis of geographical differences in the growth of Scots pine. For example, the annual photosynthetic production of a 100-year-old stand at Voronez is 3.5 times higher than in Lapland. The share consumed to needle growth (30 %) and to growth of branches (5 %) seems to be the same in all locations. In contrast, the share of fine roots is decreasing when moving from north to south. It is 20 % in Lapland, 15 % in Hyytiälä Central Finland and Kentjärvi Karelia and 15 % in Voronez South Russia. The stem masses (115­113 ton/ha) are rather similar in Hyytiälä, Kentjärvi and Voronez, but rather low (50 ton/ha) in Lapland. In Voronez the height of the trees reach 29 m being in Hyytiälä and Kentjärvi 22 m and in Lapland only 14 m. The present approach enables utilization of structural and functional knowledge, gained in places of intensive research, in the analysis of growth and development of any stand. This opens new possibilities for growth research and also for applications in forestry practice.

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Qualitative potential energy surfaces for hydrogen abstraction from alkanes containing primary, secondary and tertiary C-H bonds by a photo-excited ketone have been reported, The results suggest that the activation barriers for these processes decrease in the order primary > secondary > tertiary in agreement with the observed trend in the rate constants. The analysis of the electronic structure of the transition-state reveal that electron-transfer from hydrocarbon to ketone and formation of a new bond are almost synchronous in the hydrogen transfer process. The tunneling of hydrogen is not important in the normal temperature region even though the barriers are small.

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Many process-control systems are air-operated. In such an environment, it would be desirable and economical to use pneumatic sensors. Bubble-back pressure sensors perform quite satisfactorily, but in case of viscous inflammable and slurry-like liquids with a tendency to froth, this level sensor is inadequate. The method suggested in this paper utilizes a pneumatic capacitor, one boundary of which is formed by the liquid level, to modulate a fluid amplifier feedback oscillator. The absence of moving parts and economy obtained makes this method attractive for process-control applications. The system has been mathematically modeled and simulated on an IBM 360/44 digital computer. Experimental values compare fairly well with the theoretical results. For the range tested, the sensor is found to have a linear frequency variation with the liquid level Extended running in the laboratory shows that the system is very reliable. This system has been found insensitive to temperature variations of up to 15ðC.

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Description of gel-to-crystallite conversion process is made towards the synthesis of nanocrystalline titanates and aluminates. Thermodynamic and kinetic factors governing the conversion of a gel to meta-stable and stable nanocrystalline products(s) are discussed. Correlations between these factors and the preparative conditions employed for the syntheses of titanates and aluminates are arrived at.

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This study examines the diaconia work of the Finnish Evangelical Lutheran Church from the standpoint of clients. The role of diaconia work has grown since the early 1990s recession, and since it established itself as one of the actors along with other social organizations. Previous studies have described the changing role of diaconal work, especially from the standpoint of diaconia workers and co-operators. This research goes back to examine, beyond the activities of the diaconia work of everyday practices, its relations of ruling which are determining practices. The theoretical and methodological framework rises from the thinking of Dorothy E. Smith, the creator of institutional ethnography. Its origins are in feminism, Marxism, phenomenology, etnomethodology, and symbolic interactionism. However, it does not represent any school. Unlike the objectivity-based traditional sociology, institutional ethnography has its starting point in everyday life, and people s subjective experience of it. Everyday life is just a starting point, and is used to examine everyday life s experiences of hidden relations of ruling, linking people and organizations. The level of generalization is just on the relations of ruling. The research task is to examine those meanings of diaconia work which are embedded in its clients experiences. The research task is investigated with two questions: how diaconia work among its clients takes shape and what kinds of relations of ruling exist in diaconia work. The meanings of diaconia work come through an examination of the relations of ruling, which create new forms of diaconal work compared with previous studies. For the study, two kinds of data were collected: a questionnaire and ethnographic fieldwork. The first data set was collected from diaconal workers using the questionnaire. It gives background information of the diaconia work process from the standpoint of the clients. In the ethnographic study there were two phases. The first ethnographic material was collected from one local parish by observing, interviewing clients and diaconal workers and gathering documents. The number of observations was 36 customer appointments, and 29 interviews. The second ethnographic material was included as a part of the analysis, in which ruling relations in people s experiences were collected from the transcribed data. Close reading and narrative analysis are used as analysing methods. The analysis has three phases. First, the experiences are identified with close reading; the following step is to select some of the institutional processes that are shaping those experiences and are relevant for the research. At the third stage, those processes are investigated in order to describe analytically how they determine people s experience. The analysis produces another narrative about diaconia work, which provides tools for examining the diaconal work from a new perspective. Through the analysis it is possible to see diaconia as an exchange ratio, in which the exchange takes place between a client and a diaconia worker, but also more broadly with other actors, such as social workers, shop clerks, or with other parishioners. The exchange ratio is examined from the perspective of power which is embedded in the client s experiences. The analysis reveals that the most important relations of ruling are humiliation and randomness in the exchange ratio of diaconia work; valuating spirituality above the bodily being; and replacing official social work. The results give a map about the relations of ruling of diaconia work which gives tools to look at diaconia work s meanings to the clients. The hidden element of humiliation in the exchange ratio breaks the current picture of diaconia work. The ethos of the holistic encounters and empathic practices are shown to be of another kind when spirituality is preferred to the bodily being. Nevertheless, diaconia appears to be a place for a respectful encounter, especially in situations where the public sector s actors are retreating on liability or clients are in a life crisis. The collapse of the welfare state structures imposes on diaconia work tasks that have not previously belonged to it. At the local level, clients receive partners from diaconia workers in order to advocate them in the welfare system. Actions to influence the wider societal structures are not reached because of lacking resources. An awareness of the oppressive practices of diaconia work and their critical reviewing are the keys to the development of diaconia work, since there are such practices even in holistic and respectful diaconia work. While the research raises new information for the development of diaconia work, it also opens up new aspects for developing other kinds of social work by emphasizing the importance of taking people s experiences seriously. Keywords: diaconia work, institutional ethnography, Dorothy E. Smith, experience, customer, relations of ruling.

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The Master’s thesis is qualitative research based on interviews of 15 Chinese immigrants to Finland in order to provide a sociological perspective of the migration experience through the eyes of Chinese immigrants in the Finnish social welfare context. This research is mainly focused upon four crucial aspects of life in the settlement process: housing, employment, access to health care and child care. Inspired by Allardt’s theoretical framework ‘Having, Loving and Being’, social relationships and individual satisfaction are examined in the case of Chinese interviewees dealing with the four life aspects. Finland was not perceived as an attractive migration destination for most Chinese interviewees in the beginning. However, with longer residence in Finland, the Finnish social welfare system gradually became a crucial appealing factor in their permanent settlement in Finland. And meanwhile, social responsibility of attending their old parents in China, strong feelings of being isolated in Finland, and insufficient integration into the Finnish society were influential factors for their decision of returning to China. Social relationships with personal friends, migration brokers, schools, employers and family relatives had great influences in the four life aspects of Chinese immigrants in Finland. The social relationship with the Finnish social welfare sector is supportive to Chinese immigrants, but Chinese immigrants do not heavily rely on Finnish social protection. The housing conditions were greatly improved over time while the upward mobility in the Finnish labour market was not significant among Chinese immigrants. All Chinese immigrants were satisfied with their current housing by the time I interviewed them while most of them had subjective feelings of being alienated in the Finnish labour market, which seriously prevented them from integrating into the Finnish society. In general, Chinese immigrants were satisfied with the low cost of accessing the Finnish public health care services and affordable Finnish child day care services and financial subsidies for children from the Finnish social welfare sector. This research also suggests that employment is the central basis in well-being. Support from the Finnish social welfare sector can improve the satisfaction levels among immigrants, especially when it mitigates the effects of low-paid employment. As well, my empirical study of Chinese immigrants in Finland shows that Having (needs for materials), Loving (needs for social relations) and Being (needs for social integration) are all involved in the four concrete aspects (housing, employment, access to health care and child care).