16 resultados para Multi-objective analysis

em Doria (National Library of Finland DSpace Services) - National Library of Finland, Finland


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An alternative relation to Pareto-dominance relation is proposed. The new relation is based on ranking a set of solutions according to each separate objective and an aggregation function to calculate a scalar fitness value for each solution. The relation is called as ranking-dominance and it tries to tackle the curse of dimensionality commonly observedin evolutionary multi-objective optimization. Ranking-dominance can beused to sort a set of solutions even for a large number of objectives when Pareto-dominance relation cannot distinguish solutions from one another anymore. This permits search to advance even with a large number of objectives. It is also shown that ranking-dominance does not violate Pareto-dominance. Results indicate that selection based on ranking-dominance is able to advance search towards the Pareto-front in some cases, where selection based on Pareto-dominance stagnates. However, in some cases it is also possible that search does not proceed into direction of Pareto-front because the ranking-dominance relation permits deterioration of individual objectives. Results also show that when the number of objectives increases, selection based on just Pareto-dominance without diversity maintenance is able to advance search better than with diversity maintenance. Therefore, diversity maintenance is connive at the curse of dimensionality.

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The objective of this thesis work is to develop and study the Differential Evolution Algorithm for multi-objective optimization with constraints. Differential Evolution is an evolutionary algorithm that has gained in popularity because of its simplicity and good observed performance. Multi-objective evolutionary algorithms have become popular since they are able to produce a set of compromise solutions during the search process to approximate the Pareto-optimal front. The starting point for this thesis was an idea how Differential Evolution, with simple changes, could be extended for optimization with multiple constraints and objectives. This approach is implemented, experimentally studied, and further developed in the work. Development and study concentrates on the multi-objective optimization aspect. The main outcomes of the work are versions of a method called Generalized Differential Evolution. The versions aim to improve the performance of the method in multi-objective optimization. A diversity preservation technique that is effective and efficient compared to previous diversity preservation techniques is developed. The thesis also studies the influence of control parameters of Differential Evolution in multi-objective optimization. Proposals for initial control parameter value selection are given. Overall, the work contributes to the diversity preservation of solutions in multi-objective optimization.

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Venäjän voimakas talouskasvu on lisännyt merkittävästi myös logistiikkapalveluiden kysyntää maassa. Suuren pinta-alan, markkinapotentiaalin ja Euroopan ja Aasian välisen maantieteellisen sijainnin tarjoaman merkittävän kauttakulkupotentiaalin ansiosta Venäjä on erityisen kiinnostava investointikohde logistiikkayrityksille. Talouskasvu ei ole kuitenkaan jakautunut tasaisesti ja tämän vuoksi investoijan onkin syytä tarkoin selvittää minne Venäjän sisällä sijoittua. Tässä työssä on kartoitettu Venäjän logistiikkasektoria ja liikenneinfrastruktuuria sekä tarkasteltu kilpailutilannetta tavoitteena löytää logistiikkayrityksellekeskeisimmät sijaintikohteet Venäjällä. Moskova ja Pietari on rajattu tutkimuksen ulkopuolelle. Alan kirjallisuuteen ja aiheesta aiemmin laadittuihin tutkimuksiin perehtymällä on selvitetty yritysten sijaintipaikanvalinnalle asettamat tärkeimmät kriteerit. Logistiikkayrityksille toimivalla infrastruktuurilla on luonnollisesti oleellinen merkitys sijaintipaikkaa valittaessa, riittävän suuren markkinapotentiaalin ollessa toinen erittäin merkittävä kriteeri. Kirjallisuustarkastelun pohjalta potentiaalisiksi kohteiksi logistiikkayritykselle valikoitui 22 kaupunkia eri puolilta Venäjää. Monikriteerianalyysiin perustuvan pisteytysmenetelmän avulla toteutetussa potentiaalisten kohteiden luokittelussa kiinnostavimmiksi sijoittumiskohteiksi kohosivat Etelä-Venäjällä, Mustanmeren rannikolla sijaitsevat merkittävät satamakaupungit. Kehittyneen infrastruktuurin, merkittävän markkinapotentiaalin sekä suotuisten taloudellisten toimintaedellytysten ansiosta tarjoavat nämä erityisen merkittävän investointipotentiaalin logistiikkayrityksille.

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The changing business environment demands that chemical industrial processes be designed such that they enable the attainment of multi-objective requirements and the enhancement of innovativedesign activities. The requirements and key issues for conceptual process synthesis have changed and are no longer those of conventional process design; there is an increased emphasis on innovative research to develop new concepts, novel techniques and processes. A central issue, how to enhance the creativity of the design process, requires further research into methodologies. The thesis presentsa conflict-based methodology for conceptual process synthesis. The motivation of the work is to support decision-making in design and synthesis and to enhance the creativity of design activities. It deals with the multi-objective requirements and combinatorially complex nature of process synthesis. The work is carriedout based on a new concept and design paradigm adapted from Theory of InventiveProblem Solving methodology (TRIZ). TRIZ is claimed to be a `systematic creativity' framework thanks to its knowledge based and evolutionary-directed nature. The conflict concept, when applied to process synthesis, throws new lights on design problems and activities. The conflict model is proposed as a way of describing design problems and handling design information. The design tasks are represented as groups of conflicts and conflict table is built as the design tool. The general design paradigm is formulated to handle conflicts in both the early and detailed design stages. The methodology developed reflects the conflict nature of process design and synthesis. The method is implemented and verified through case studies of distillation system design, reactor/separator network design and waste minimization. Handling the various levels of conflicts evolve possible design alternatives in a systematic procedure which consists of establishing an efficient and compact solution space for the detailed design stage. The approach also provides the information to bridge the gap between the application of qualitative knowledge in the early stage and quantitative techniques in the detailed design stage. Enhancement of creativity is realized through the better understanding of the design problems gained from the conflict concept and in the improvement in engineering design practice via the systematic nature of the approach.

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Over the past few decades, turbulent change has characterized the situation in the media industry. It has been noted that digitalization and new media are strongly influencing the industry: it is changing the existing market dynamics and requires new strategies. Prior research on the impact of digitalization and the Internet has emphasized news-focused media such as newspaper publishing and broadcasting, yet magazine publishing is very seldom the focus of the research. This study examines how the Internetimpacts magazine publishing. The work presents a multi-level analysis on the role and impact of the Internet on magazine products, companies and industry. The study is founded on strategic management, technology management and media economics literature. This study consists of two parts. The first part introduces the research topic and discusses the overall results of the study. The second part comprises five research publications. Qualitative research methods are used throughout. The results of the study indicate that the Internet has not had a disruptive effect on magazine publishing, and that its strategic implications could rather be considered complementary to the print magazine and the business as a whole. It seems that the co-specialized assets, together with market-related competencies and unchanged core competence have protected established firms from the disruptive effect of the new technology in magazine publishing. In addition, it seems that the Internet offers a valuable possibility to build and nourish customer relationships. The study contributes tomedia management and economics research by moving from product- or industry-level investigations towards a strategic-management perspective.

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This master’s thesis is focused on the active magnetic bearings control, specifically the robust control. As carrying out of such kind of control used mixed H2/Hinf controller. So the goal of this work is to design it using Robust Control Toolbox™ in MATLAB and compare it performance and robustness with Hinf robust controller characteristics. But only one degree-of-freedom controller considered.

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The overriding aim of this drama educational case study is to deepen the understanding of meaning making in a creative intercultural youth theatre process and to examine it in the context of the 10th European Children's TheatreEncounter. The research task is to give a theoretical description of some key features of a creative drama process as the basis for theory about meaning makingin physical theatre. The first task is to illuminate the culture-historical connections of the multilayered practice of the EDERED-association. The second taskis to analyse and interpret theatrical meaning making. The ethnographical research site is regarded as a theatrical event. The analysis of the theatrical eventis divided into four segments: cultural contexts, contextual theatricality, theatrical playing and playing culture. These segments are connected with four research questions: What are the cultural contexts of a creative drama process? How can the organisation of the Encounter, genres, aesthetic codes and perception ofcodes be seen to influence the lived experiences of the participants? What are some of the key phases and characteristics in a creative practice? What kind of cultural learning can be interpreted from the performance texts? The interpretative question concerns identity and community (re)construction. How are the categories, `community´ and `child´ constructed in the Encounter culture? In this drama educational case study the research material (transcribed interviews, coded questionnaire answers, participant drawings, videotaped process text and performance texts) are examined in a multi-method analysis in the meta-theoretical framework of Dewey's naturalistic pragmatism. A three-dimensional research interest through a combination of lived experiences, social contexts and cultural-aesthetical practices compared with drama-educational practices required the methodological project of cultural studies. Furthermore, the critical interpretation of cultural texts is divided into three levels of analyses which are called description, structural analysis and theoretical interpretation. Dialogic validity (truthfulness, self-reflexivity and polyvocality) is combined with contextual validity (sensitivity to social context and awareness of historicity) and with deconstructive validity (awareness of the social discourses). My research suggests that itis possible, by means of physical theatre, to construct symbolic worlds where questions about intercultural identity and multilingual community are examined and where provisional answers are constructed in social interaction.

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This study focuses on the relationship between organizational network competence and the internationalization process of small- and medium sized enterprises (SMEs). Over recent decades, the global business environment has become increasingly conducive to internationalization of small firms. A central facilitating factor in the process has been the emergence of networked business relationships between internationalizing firms. Research on SME internationalization has found that certain types of structures and dynamics of business networks allow SMEs access to the resources they need to enter foreign markets. This consequently means that their internationalization often becomes to depend on the networks they are embedded in. However, research so far has mostly ignored the possibility that the organizational ability to develop and manage business network relationships, network competence, may be a major underlying factor in determining how well SMEs can leverage their network relationships to enter foreign markets and consequently may determine in large part how successful their internationalization process turns out to be. This study aims to respond to those gaps, by empirically examining how the development of network competence in internationalizing SMEs influences the internationalization outcomes that they can expect, and how such network competence is conceptualized and developed. Using a mixed methods approach, survey data collected from 298 Finnish SMEs across five industry sectors is first used to examine how levels of network competence are related to internationalization propensity of SMEs and their subsequent international performance, growth and profitability as internationally operating firms. In order to illustrate in more detail the ways in which network competence is conceptualized and how it develops during the internationalization process of an SME, qualitative data from internationally operating Finnish SMEs are used. Longitudinal interview data of an internationalizing Finnish SME is accompanied by data gathered through a series of semistructured interviews of Finnish and Russian managers involved in mutual business relationship dyads. Structurally, this thesis examines the research issue as an article-based dissertation, consisting of five journal and conference publications. Three of these publications are based on the quantitative data, and the remaining two apply the qualitative interview data. The results find several aspects where network competence has a positive influence on the success of internationalizing SMEs, how it develops and what it entails conceptually in this context. Quantitatively, the level of network competence is found to have a positive relationship to various internationalization outcomes, including the propensity of SMEs to enter foreign markets and on their subsequent international performance, their growth and their profitability. Additionally, the positive relationship is divided between the relationship-specific and cross-relational dimension of network competence, in that the influence of the former is relevant for the propensity to internationalize, while the latter is for the growth and profitability of the already internationalized SMEs. Qualitatively, the results suggest, firstly, that the development process of network competence does not necessarily precede the start of the internationalization process, but may occur through a gradual learning process alongside it. And secondly, the results also imply that the conceptualization of network competence by Finnish managers of internationally operating Finnish SMEs is structurally distinct from that of their culturally distinct partner managers in Russia. This study contributes to the literature on SME internationalization in several ways. Firstly, it introduces operationalized organizational competencies to the literature on internationalization of SMEs, which has so far mainly examined the influence of business networking on the internationalization process without having such an organizational viewpoint. Furthermore, this study provides a multi-level analysis of the determinants of successful SME internationalization, by examining various strategic and performance outcomes across the process. These results also contribute to the literature on organizational strategy of internationalizing SMEs, by clarifying how different dimensions of business networking may be optimal in different phases of the internationalization process. Conceptually, the results of this study contribute to the literature on competence development and SME internationalization, by illustrating how the development process of network competence may occur during internationalization process. Thus, they also contribute to the discussion on how SMEs are able to influence the dynamics and structures of their business networks over time. Finally, this study contributes to the literature on the role of culture in the internationalization process, by implying that the cultural background of the manager of the SME may determine whether business networking and network competence is seen as an organizational-level or an individual level capability. The study also includes some additional contributions to the literature on dynamic capabilities in strategic management, and on that of strategic business networks. These include further clarifying the exact nature and tangibility of dynamic capabilities, and being one of the first studies to introduce constructs from both dynamic capabilities and business network literature to the field of international entrepreneurship. And finally, the study also has some contribution on the two streams of literature, in illustrating how both dyadic and network-level capabilities may be relevant, depending on the current strategic goals and market position of the firm. Keywords: network competence, internationalizatio

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Context: BL Lacs are the most numerous extragalactic objects which are detected in Very High Energy (VHE) gamma-rays band. They are a subclass of blazars. Large flux variability amplitude, sometimes happens in very short time scale, is a common characteristic of them. Significant optical polarization is another main characteristics of BL Lacs. BL Lacs' spectra have a continuous and featureless Spectral Energy Distribution (SED) which have two peaks. Among 1442 BL Lacs in the Roma-BZB catalogue, only 51 are detected in VHE gamma-rays band. BL Lacs are most numerous (more than 50% of 514 objects) objects among the sources that are detected above 10 GeV by FERMI-LAT. Therefore, many BL Lacs are expected to be discovered in VHE gamma-rays band. However, due to the limitation on current and near future technology of Imaging Air Cherenkov Telescope, astronomers are forced to predict whether an object emits VHE gamma-rays or not. Some VHE gamma-ray prediction methods are already introduced but still are not confirmed. Cross band correlations are the building blocks of introducing VHE gamma-rays prediction method. Aims: We will attempt to investigate cross band correlations between flux energy density, luminosity and spectral index of the sample. Also, we will check whether recently discovered MAGIC J2001+435 is a typical BL Lac. Methods: We select a sample of 42 TeV BL Lacs and collect 20 of their properties within five energy bands from literature and Tuorla blazar monitoring program database. All of the data are synchronized to be comparable to each other. Finally, we choose 55 pair of datasets for cross band correlations finding and investigating whether there is any correlation between each pair. For MAGIC J2001+435 we analyze the publicly available SWIFT-XRT data, and use the still unpublished VHE gamma-rays data from MAGIC collaboration. The results are compared to the other sources of the sample. Results: Low state luminosity of multiple detected VHE gamma-rays is strongly correlated luminosities in all other bands. However, the high state does not show such strong correlations. VHE gamma-rays single detected sources have similar behaviour to the low state of multiple detected ones. Finally, MAGIC J2001+435 is a typical TeV BL Lac. However, for some of the properties this source is located at the edge of the whole sample (e.g. in terms of X-rays flux). Keywords: BL Lac(s), Population study, Correlations finding, Multi wavelengths analysis, VHE gamma-rays, gamma-rays, X-rays, Optical, Radio

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Intelligence from a human source, that is falsely thought to be true, is potentially more harmful than a total lack of it. The veracity assessment of the gathered intelligence is one of the most important phases of the intelligence process. Lie detection and veracity assessment methods have been studied widely but a comprehensive analysis of these methods’ applicability is lacking. There are some problems related to the efficacy of lie detection and veracity assessment. According to a conventional belief an almighty lie detection method, that is almost 100% accurate and suitable for any social encounter, exists. However, scientific studies have shown that this is not the case, and popular approaches are often over simplified. The main research question of this study was: What is the applicability of veracity assessment methods, which are reliable and are based on scientific proof, in terms of the following criteria? o Accuracy, i.e. probability of detecting deception successfully o Ease of Use, i.e. easiness to apply the method correctly o Time Required to apply the method reliably o No Need for Special Equipment o Unobtrusiveness of the method In order to get an answer to the main research question, the following supporting research questions were answered first: What kinds of interviewing and interrogation techniques exist and how could they be used in the intelligence interview context, what kinds of lie detection and veracity assessment methods exist that are reliable and are based on scientific proof and what kind of uncertainty and other limitations are included in these methods? Two major databases, Google Scholar and Science Direct, were used to search and collect existing topic related studies and other papers. After the search phase, the understanding of the existing lie detection and veracity assessment methods was established through a meta-analysis. Multi Criteria Analysis utilizing Analytic Hierarchy Process was conducted to compare scientifically valid lie detection and veracity assessment methods in terms of the assessment criteria. In addition, a field study was arranged to get a firsthand experience of the applicability of different lie detection and veracity assessment methods. The Studied Features of Discourse and the Studied Features of Nonverbal Communication gained the highest ranking in overall applicability. They were assessed to be the easiest and fastest to apply, and to have required temporal and contextual sensitivity. The Plausibility and Inner Logic of the Statement, the Method for Assessing the Credibility of Evidence and the Criteria Based Content Analysis were also found to be useful, but with some limitations. The Discourse Analysis and the Polygraph were assessed to be the least applicable. Results from the field study support these findings. However, it was also discovered that the most applicable methods are not entirely troublefree either. In addition, this study highlighted that three channels of information, Content, Discourse and Nonverbal Communication, can be subjected to veracity assessment methods that are scientifically defensible. There is at least one reliable and applicable veracity assessment method for each of the three channels. All of the methods require disciplined application and a scientific working approach. There are no quick gains if high accuracy and reliability is desired. Since most of the current lie detection studies are concentrated around a scenario, where roughly half of the assessed people are totally truthful and the other half are liars who present a well prepared cover story, it is proposed that in future studies lie detection and veracity assessment methods are tested against partially truthful human sources. This kind of test setup would highlight new challenges and opportunities for the use of existing and widely studied lie detection methods, as well as for the modern ones that are still under development.

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Due to the intense international competition, demanding, and sophisticated customers, and diverse transforming technological change, organizations need to renew their products and services by allocating resources on research and development (R&D). Managing R&D is complex, but vital for many organizations to survive in the dynamic, turbulent environment. Thus, the increased interest among decision-makers towards finding the right performance measures for R&D is understandable. The measures or evaluation methods of R&D performance can be utilized for multiple purposes; for strategic control, for justifying the existence of R&D, for providing information and improving activities, as well as for the purposes of motivating and benchmarking. The earlier research in the field of R&D performance analysis has generally focused on either the activities and considerable factors and dimensions - e.g. strategic perspectives, purposes of measurement, levels of analysis, types of R&D or phases of R&D process - prior to the selection of R&Dperformance measures, or on proposed principles or actual implementation of theselection or design processes of R&D performance measures or measurement systems. This study aims at integrating the consideration of essential factors anddimensions of R&D performance analysis to developed selection processes of R&D measures, which have been applied in real-world organizations. The earlier models for corporate performance measurement that can be found in the literature, are to some extent adaptable also to the development of measurement systemsand selecting the measures in R&D activities. However, it is necessary to emphasize the special aspects related to the measurement of R&D performance in a way that make the development of new approaches for especially R&D performance measure selection necessary: First, the special characteristics of R&D - such as the long time lag between the inputs and outcomes, as well as the overall complexity and difficult coordination of activities - influence the R&D performance analysis problems, such as the need for more systematic, objective, balanced and multi-dimensional approaches for R&D measure selection, as well as the incompatibility of R&D measurement systems to other corporate measurement systems and vice versa. Secondly, the above-mentioned characteristics and challenges bring forth the significance of the influencing factors and dimensions that need to be recognized in order to derive the selection criteria for measures and choose the right R&D metrics, which is the most crucial step in the measurement system development process. The main purpose of this study is to support the management and control of the research and development activities of organizations by increasing the understanding of R&D performance analysis, clarifying the main factors related to the selection of R&D measures and by providing novel types of approaches and methods for systematizing the whole strategy- and business-based selection and development process of R&D indicators.The final aim of the research is to support the management in their decision making of R&D with suitable, systematically chosen measures or evaluation methods of R&D performance. Thus, the emphasis in most sub-areas of the present research has been on the promotion of the selection and development process of R&D indicators with the help of the different tools and decision support systems, i.e. the research has normative features through providing guidelines by novel types of approaches. The gathering of data and conducting case studies in metal and electronic industry companies, in the information and communications technology (ICT) sector, and in non-profit organizations helped us to formulate a comprehensive picture of the main challenges of R&D performance analysis in different organizations, which is essential, as recognition of the most importantproblem areas is a very crucial element in the constructive research approach utilized in this study. Multiple practical benefits regarding the defined problemareas could be found in the various constructed approaches presented in this dissertation: 1) the selection of R&D measures became more systematic when compared to the empirical analysis, as it was common that there were no systematic approaches utilized in the studied organizations earlier; 2) the evaluation methods or measures of R&D chosen with the help of the developed approaches can be more directly utilized in the decision-making, because of the thorough consideration of the purpose of measurement, as well as other dimensions of measurement; 3) more balance to the set of R&D measures was desired and gained throughthe holistic approaches to the selection processes; and 4) more objectivity wasgained through organizing the selection processes, as the earlier systems were considered subjective in many organizations. Scientifically, this dissertation aims to make a contribution to the present body of knowledge of R&D performance analysis by facilitating dealing with the versatility and challenges of R&D performance analysis, as well as the factors and dimensions influencing the selection of R&D performance measures, and by integrating these aspects to the developed novel types of approaches, methods and tools in the selection processes of R&D measures, applied in real-world organizations. In the whole research, facilitation of dealing with the versatility and challenges in R&D performance analysis, as well as the factors and dimensions influencing the R&D performance measure selection are strongly integrated with the constructed approaches. Thus, the research meets the above-mentioned purposes and objectives of the dissertation from the scientific as well as from the practical point of view.

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Rautateillä käytettävät tavaravaunut ovat vanhenemassa hyvin nopeasti; tämä koskee niin Venäjää, Suomea, Ruotsia kuin laajemminkin Eurooppaa. Venäjällä ja Euroopassa on käytössä runsaasti vaunuja, jotka ovat jo ylittäneet niille suositeltavan käyttöiän. Silti niitä käytetään kuljetuksissa, kun näitä korvaavia uusia vaunuja ei ole tarpeeksi saatavilla. Uusimmat vaunut ovat yleensä vaunuja vuokraavien yritysten tai uusien rautatieoperaattorien hankkimia - tämä koskee erityisesti Venäjää, jossa vaunuvuokraus on noussut erittäin suosituksi vaihtoehdoksi. Ennusteissa kerrotaan vaunupulan kasvavan ainakin vuoteen 2010 saakka. Jos rautateiden suosio rahtikuljetusmuotona kasvaa, niin voimistuva vaunukysyntä jatkuu huomattavan paljon pidemmän aikaa. Euroopan ja Venäjän vaunukannan tilanne näkyy myös sitä palvelevan konepajateollisuuden ongelmina - yleisesti ottaen alan eurooppalaiset yritykset ovat heikosti kannattavia ja niiden liikevaihto ei juuri kasva, venäläiset ja ukrainalaiset yritykset ovat olleet samassa tilanteessa, joskin aivan viime vuosina tilanne on osassa kääntynyt paremmaksi. Kun näiden maanosien yritysten liikevaihtoa, voittoa ja omistaja-arvoa verrataan yhdysvaltalaisiin kilpailijoihin, huomataan että jälkimmäisten suoriutuminen on huomattavan paljon parempaa, ja näillä yrityksillä on myös kyky maksaa osinkoja omistajilleen. Tutkimuksen tarkoituksena oli kehittää uuden tyyppinen kuljetusvaunu Suomen, Venäjän sekä mahdollisesti myös Kiinan väliseen liikenteeseen. Vaunutyypin tarkoituksena olisi kyetä toimimaan monikäyttöisenä, niin raaka-aineiden kuin konttienkin kuljetuksessa, tasapainottaen kuljetusmuotojen aiheuttamaa kuljetuspaino-ongelmaa. Kehitystyön pohjana käytimme yli 1000 venäläisen vaunutyypin tietokantaa, josta valitsimme Data Envelopment Analysis -menetelmällä soveliaimmat vaunut kontinkuljetukseen (lähemmin tarkastelimme n. 40 vaunutyyppiä), jättäen mahdollisimman vähän tyhjää tilaa junaan, mutta silti kyeten kantamaan valitun konttilastin. Kun kantokykyongelmia venäläisissä vaunuissa ei useinkaan ole, on vertailu tehtävissä tavarajunan pituuden ja kokonaispainon perusteella. Simuloituamme yhdistettyihin kuljetuksiin soveliasta vaunutyyppiä käytännössä löytyvässä kuljetusverkostossa (esim. raakapuuta Suomeen tai Kiinaan ja kontteja takaisin Venäjän suuntaan), huomasimme lyhemmän vaunupituuden sisältävän kustannusetua, erityisesti raakaainekuljetuksissa, mutta myös rajanylityspaikkojen mahdollisesti vähentyessä. Lyhempi vaunutyyppi on myös joustavampi erilaisten konttipituuksien suhteen (40 jalan kontin käyttö on yleistynyt viime vuosina). Työn lopuksi ehdotamme uuden vaunutyypin tuotantotavaksi verkostomaista lähestymistapaa, jossa osa vaunusta tehtäisiin Suomessa ja osa Venäjällä ja/tai Ukrainassa. Vaunutyypin tulisi olla rekisteröity Venäjälle, sillä silloin sitä voi käyttää Suomen ja Venäjän, kuten myös soveltuvin osin Venäjän ja Kiinan välisessä liikenteessä.

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Due to functional requirement of a structural detail brackets with and without scallop are frequently used in bridges, decks, ships and offshore structure. Scallops are designed to serve as passage way for fluids, to reduce weld length and plate distortions. Moreover, scallops are used to avoid intersection of two or more welds for the fact that there is the presence of inventible inherent initial crack except for full penetrated weld and the formation of multi-axial stress state at the weld intersection. Welding all around the scallop corner increase the possibility of brittle fracture even for the case the bracket is not loaded by primary load. Avoiding of scallop will establish an initial crack in the corner if bracket is welded by fillet welds. If the two weld run pass had crossed, this would have given a 3D residual stress situation. Therefore the presences and absence of scallop necessitates the 3D FEA fatigue resistance of both types of brackets using effective notch stress approach ( ). FEMAP 10.1 with NX NASTRAN was used for the 3D FEA. The first and main objective of this research was to investigate and compare the fatigue resistance of brackets with and without scallop. The secondary goal was the fatigue design of scallops in case they cannot be avoided for some reason. The fatigue resistance for both types of brackets was determined based on approach using 1 mm fictitiously rounded radius based on IIW recommendation. Identical geometrical, boundary and loading conditions were used for the determination and comparison of fatigue resistance of both types of brackets using linear 3D FEA. Moreover the size effect of bracket length was also studied using 2D SHELL element FEA. In the case of brackets with scallop the flange plate weld toe at the corner of the scallop was found to exhibit the highest and made the flange plate weld toe critical for fatigue failure. Whereas weld root and weld toe at the weld intersections were the highly stressed location for brackets without scallop. Thus weld toe for brackets with scallop, and weld root and weld toe for brackets without scallop were found to be the critical area for fatigue failure. Employing identical parameters on both types of brackets, brackets without scallop had the highest except for full penetrated weld. Furthermore the fatigue resistance of brackets without scallop was highly affected by the lack of weld penetration length and it was found out that decreased as the weld penetration was increased. Despite the fact that the very presence of scallop reduces the stiffness and also same time induce stress concentration, based on the 3D FEA it is worth concluding that using scallop provided better fatigue resistance when both types of brackets were fillet welded. However brackets without scallop had the highest fatigue resistance when full penetration weld was used. This thesis also showed that weld toe for brackets with scallop was the only highly stressed area unlike brackets without scallop in which both weld toe and weld root were the critical locations for fatigue failure when different types of boundary conditions were used. Weld throat thickness, plate thickness, scallop radius, lack of weld penetration length, boundary condition and weld quality affected the fatigue resistance of both types of brackets. And as a result, bracket design procedure, especially welding quality and post weld treatment techniques significantly affect the fatigue resistance of both type of brackets.