Application and development of numerical methods for the modelling of innovative gas cooled fission reactors

Innovative gas cooled reactors, such as the pebble bed reactor (PBR) and the gas cooled fast reactor (GFR) offer higher efficiency and new application areas for nuclear energy. Numerical methods were applied and developed to analyse the specific features of these reactor types with fully three dimensional calculation models. In the first part of this thesis, discrete element method (DEM) was used for a physically realistic modelling of the packing of fuel pebbles in PBR geometries and methods were developed for utilising the DEM results in subsequent reactor physics and thermal-hydraulics calculations. In the second part, the flow and heat transfer for a single gas cooled fuel rod of a GFR were investigated with computational fluid dynamics (CFD) methods. An in-house DEM implementation was validated and used for packing simulations, in which the effect of several parameters on the resulting average packing density was investigated. The restitution coefficient was found out to have the most significant effect. The results can be utilised in further work to obtain a pebble bed with a specific packing density. The packing structures of selected pebble beds were also analysed in detail and local variations in the packing density were observed, which should be taken into account especially in the reactor core thermal-hydraulic analyses. Two open source DEM codes were used to produce stochastic pebble bed configurations to add realism and improve the accuracy of criticality calculations performed with the Monte Carlo reactor physics code Serpent. Russian ASTRA criticality experiments were calculated. Pebble beds corresponding to the experimental specifications within measurement uncertainties were produced in DEM simulations and successfully exported into the subsequent reactor physics analysis. With the developed approach, two typical issues in Monte Carlo reactor physics calculations of pebble bed geometries were avoided. A novel method was developed and implemented as a MATLAB code to calculate porosities in the cells of a CFD calculation mesh constructed over a pebble bed obtained from DEM simulations. The code was further developed to distribute power and temperature data accurately between discrete based reactor physics and continuum based thermal-hydraulics models to enable coupled reactor core calculations. The developed method was also found useful for analysing sphere packings in general. CFD calculations were performed to investigate the pressure losses and heat transfer in three dimensional air cooled smooth and rib roughened rod geometries, housed inside a hexagonal flow channel representing a sub-channel of a single fuel rod of a GFR. The CFD geometry represented the test section of the L-STAR experimental facility at Karlsruhe Institute of Technology and the calculation results were compared to the corresponding experimental results. Knowledge was gained of the adequacy of various turbulence models and of the modelling requirements and issues related to the specific application. The obtained pressure loss results were in a relatively good agreement with the experimental data. Heat transfer in the smooth rod geometry was somewhat under predicted, which can partly be explained by unaccounted heat losses and uncertainties. In the rib roughened geometry heat transfer was severely under predicted by the used realisable k − epsilon turbulence model. An additional calculation with a v2 − f turbulence model showed significant improvement in the heat transfer results, which is most likely due to the better performance of the model in separated flow problems. Further investigations are suggested before using CFD to make conclusions of the heat transfer performance of rib roughened GFR fuel rod geometries. It is suggested that the viewpoints of numerical modelling are included in the planning of experiments to ease the challenging model construction and simulations and to avoid introducing additional sources of uncertainties. To facilitate the use of advanced calculation approaches, multi-physical aspects in experiments should also be considered and documented in a reasonable detail.

Transition management in action within the context of nutrient economy

Tämä työ tutkii ja tarkastelee transitio-kokeilua ravinnetaloudessa. Transitio-kokeilu on toimintatutkimusprojekti, joka toteutetaan systeemisen muutoksen ajattelun mukaisesti alhaalta ylöspäin. Ravinnetalous määritetään tarkemmin työn kautta sekä analysoidaan monitaso-perspektiivin näkökulmasta. Ravinnetalous on terminä varsin tuntematon ja tarvitsee enemmän tunnettavuutta laajemman yleisön edessä. Transitio-areenan ja transitio-visioiden kehittäminen ovat työn keskipisteessä, koska ne ovat tärkeimpiä vaiheita transition alkuvaiheessa. Joukko sidosryhmätoimijoita osallistuu transitio areenaan sekä visioiden jatkokehittelyyn. Visio(t) luodaan ensisijaisesti backcasting-menetelmällä, jota myös täydennetään tavanomaisella ennustamisella. Backcasting- menetelmä on osin osallistava ja siinä käytetään ravinteiden planeettarajoja kvantitatiivisina pääperiaatteina, minkä tuloksena myös visiot ovat osin kvantitatiivisia. Transitio areenan kokoaminen ja fasilitointi aiheuttavat hankalia kysymyksiä, jotka tarvitsevat jatko-tutkimusta. Alhaalta-ylöspäin organisoitu transitio-arena houkuttelee niche-toimijoita, mutta epäonnistuu sitouttamaan julkisen vallan toimijoita. Toimintamallin voimasuhteet, politiikka ja transition vakiinnuttaminen tulisivat olla jatko-toimenpiteinä niin tutkimuksessa kuin toiminnassakin.

Language-specific aspects of reading acquisition: the case of Russian

We have investigated Russian children’s reading acquisition during an intermediate period in their development: after literacy onset, but before they have acquired well-developed decoding skills. The results of our study suggest that Russian first graders rely primarily on phonemes and syllables as reading grain-size units. Phonemic awareness seems to have reached the metalinguistic level more rapidly than syllabic awareness after the onset of reading instruction, the reversal which is typical for the initial stages of formal reading instruction creating external demand for phonemic awareness. Another reason might be the inherent instability of syllabic boundaries in Russian. We have shown that body-coda is a more natural representation of subsyllabic structure in Russian than onset-rime. We also found that Russian children displayed variability of syllable onset and offset decisions which can be attributed to the lack of congruence between syllabic and morphemic word division in Russian. We suggest that fuzziness of syllable boundary decisions is a sign of the transitional nature of this stage in the reading development and it indicates progress towards an awareness of morphologically determined closed syllables. Our study also showed that orthographic complexity exerts an influence on reading in Russian from the very start of reading acquisition. Besides, we found that Russian first graders experience fluency difficulties in reading orthographically simple words and nonwords of two and more syllables. The transition from monosyllabic to bisyllabic lexical items constitutes a certain threshold, for which the syllabic structure seemed to be of no difference. When we compared the outcomes of the Russian children with the ones produced by speakers of other languages, we discovered that in the tasks which could be performed with the help of alphabetic recoding Russian children’s accuracy was comparable to that of children learning to read in relatively shallow orthographies. In tasks where this approach works only partially, Russian children demonstrated accuracy results similar to those in deeper orthographies. This pattern of moderate results in accuracy and excellent performance in terms of reaction times is an indication that children apply phonological recoding as their dominant strategy to various reading tasks and are only beginning to develop suitable multiple strategies in dealing with orthographically complex material. The development of these strategies is not completed during Grade 1 and the shift towards diversification of strategies apparently continues in Grade 2.

How CSR and stakeholder engagement encourage the development of Industrial symbiosis from the management viewpoint?

The thesis aims to understand how CSR and stakeholder engagement can contribute to the development of industrial symbiosis. Theory suggests that corporate social responsibility and stakeholder engagement theories have many similar aspects that correlate with the development of industrial symbiosis. This study is qualitative and empirical suggestions are derived from integrative analysis of literature, secondary data and case study analysis. The empirical findings from the interviews support the framework that is created from the findings of the literature review. The results discovered throughout the thesis research suggest that CSR functions as a theoretical background for industrial symbiosis and stakeholder engagement helps develop more thorough understandings of it from the management viewpoint. Empirical findings and literature review also suggest that in the developing of industrial symbiosis the key aspect are the social characteristics such as a robust management structure, trust between partners and long-term commitment to the common goals that support the development of these symbioses. Also, communication and transparency supports the development of industrial symbiosis. For managerial contribution, this thesis presents organizational practices that can help managers to understand how they can engage in effective engagement with stakeholders in the development of industrial symbiosis.

Development of internet-based value added services in housing estate business in Russia

Value added services are becoming increasingly popular as they increase the perceived value of the core product and can be a strong method of attracting customers and motivating them to make a choice. The purpose of this research is to develop internet-based value added services for housing estate business in Russia. The research is a case study of Russian housing estate market utilising a triangulation of methods for better results. For the qualitative data analysis, 7 interviews with heads of regional departments of construction companies from different regions of Russia were conducted. For the quantitative data analysis, a survey of 128 inhabitants of Saint-Petersburg housing estates was held. Factor analysis and descriptive statistics including cross-tabulations and chi-square tests for significance were used to analyse the results. In this study, a list 19 value added services that can be provided through online platforms in housing estate market was developed. These services fall into three big groups: social networking services, compulsory and additional services. Additionally, the question of monetisation of online platforms in housing estate market was discussed and three business models were suggested.

The Role Of Social Networks In New Venture Internationalization: Case Of Russian And Finnish Firms

The purpose of current master thesis research is to investigate the role of social networks in internationalization of Russian and Finnish firms. Literature review of existing empirical researches on the topic is conducted in order to identify the gap, which is fulfilled by empirical research of 4 Russian and 1 Finnish firm that have established international operations no later than 8 years since their foundation. In-depth semi-structured interviews have shown that business network has been an influencing factor in firms’ internationalization and that even if social network is not the driver of internationalization, it becomes important when a company has established international presence and is working on its enlargement. The study has both theoretical and practical contribution by contributing to research of Russian and Finnish firms’ internationalization and by showing examples of successful foreign market entry of companies from different industries. General practical implication of current thesis is that it shows the efficient ways of entrepreneurs’ social network usage in business development in international scope.

Development of a New Welding Product Quality Control and Management System Model for China

The Chinese welding industry is growing every year due to rapid development of the Chinese economy. Increasingly, companies around the world are looking to use Chinese enterprises as their cooperation partners. However, the Chinese welding industry also has its weaknesses, such as relatively low quality and weak management. A modern, advanced welding management system appropriate for local socio-economic conditions is required to enable Chinese enterprises to enhance further their business development. The thesis researches the design and implementation of a new welding quality management system for China. This new system is called ‗welding production quality control management model in China‘ (WQMC). Constructed on the basis of analysis of a survey and in-company interviews, the welding management system comprises the following different elements and perspectives: a ‗Localized congenital existing problem resolution strategies‘ (LCEPRS) database, a ‗human factor designed training system‘ (HFDT) training strategy, the theory of modular design, ISO 3834 requirements, total welding management (TWM), and lean manufacturing (LEAN) theory. The methods used in the research are literature review, questionnaires, interviews, and the author‘s model design experiences and observations, i.e. the approach is primarily qualitative and phenomenological. The thesis describes the design and implementation of a HFDT strategy in Chinese welding companies. Such training is an effective way to increase employees‘ awareness of quality and issues associated with quality assurance. The study identified widely existing problems in the Chinese welding industry and constructed a LCEPRS database that can be used in efforts to mitigate and avoid common problems. The work uses the theory of modular design, TWM and LEAN as tools for the implementation of the WQMC system.

Impact of Agricultural Credit in the.Agricultural Development of Kuttanad

Introduction of agrarian reforms and introduction of new technology increased dependence on casual labourers. High labour absorption in the subsistence agriculture and increased price of input resulted in high cost of cultivation. Price of paddy did not rise correspondingly. As a result subsistence economy's future is bleak. The purpose of the _study is to examine these arguments and related issues with the help of empirical evidence from Kuttanad. The credit schemes are designed to help farmers to earn higher incomes by larger output brought either by an increase in area or by an improvement in yield rates or both. It is difficult to isolate the impact of agricultural credit on agricultural development. Because agricultural development is the combined effect of all inputs. The specific .criteria selected for analysing the impact of agricultural icredit are how increased supply of credit would bring changes ‘in capital formation, agrarian relations, informal lending and its cost and the changes in area, output, introduction of new technology, income, savings and employment of farm households.

Technological Change and the Development of the Primary Fishing Industry of Kerala - A Study of Limited Growth

Induction of growth in the primary marine fishing industry of Kerala is a sine gua Qgn for improving the economy of the fishermen, the state's domestic product as well as earning more foreign exchange for the country. The State Administration has been trying to instil growth into the industry eversince the output of the industry showed marked sign of decline (particularly after 1975). Significantly, it has attempted to strengthen the traditional sector, (which is considered to be the crucial sector of the primary marine fishing industry of the state) by introducing intermediate technology and by revamping the organisational structure of the industry. But it appears that the production system in the primary marine fishing industry of Kerala has been severely constrained by the existing technology, organisation of production and marketing institutions. Regeneration of growth in the industry calls forth an understanding of the 'process' of growth in the industry and the need to réorganise it with new technology, and new organisations. The present study is an attempt to unraval the process of growth in the primary marine fishing industry of Kerala since 1951

Coase and international business: the origin and development of internalisation theory

The internalisation theory of the multinational enterprise is a significant intellectual legacy of Ronald Coase. US direct investment in Europe became highly political in the 1960s, and neoclassical trade theory had no explanation. A theory of the multi-plant enterprise was required, and internalisation theory filled this gap. Using Coasian economics to explain the ownership of production plants, and the geography of trade to explain their location, internalisation theory offered a comprehensive account of MNEs and their role in the international economy. This paper outlines the development of the theory, explains the Coasian contribution, and examines in detail the early work of Hymer, McManus and Buckley and Casson. It then reviews the current state of internalisation theory and suggests some future developments.

The Development of Swedish Tourism Public Policy 1930-2010

In this article, the development and changes in Swedish public policy relating to tourism from the 1930s to 2010 is described and interpreted from a political economy perspective. A case study, compiled from mainly secondary sources, is analyzed from a theoretical framework based on regulation theory. The purpose with this study is to increase the understanding of how the macro political economy context has influenced the policy-making in tourism in Sweden, but also to make a contribution to an area which seems to be quite neglected when it comes to research. The changes are analyzed according to the three periods denoted as pre-Fordism (mid-19th century-1930s), Fordism (1930s-1970s) and post-Fordism (1970s to present). It is observed how the general changes between these periods regarding aspects such as regulation and deregulation, and the degree of state involvement, have affected tourism policy making. The tourism policy making has changed from being insignificant, to a high degree of state involvement including planning, control and supervision, to a situation where the market rather than government regulation is considered as state of the art. 

Information technology for development of small and medium-sized exporters in Latin America and East Asia

Includes bibliography

Inclusion of the European Nordic model in the debate concerning social protection reform: the long-term development of Nordic welfare systems (1890-2005) and their transferability to Latin America in the twenty-first century

Includes bibliography

External desequilibrium in the economic development of Latin America: the case of Mexico

Includes bibliography