105 resultados para Doty, Alan


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Finnish education politics presume that basic education should be equal to all students. While organising craft education equality can be understood as similarity or as possibility to choose. The possibility to be able to choose whether textile or technical craft despite of one´s gender has been the aim of laws and curriculums already over 30 years. In practice it´s almost impossible to students to ignore feminine and masculine roles that go deep into our culture. Choosing craft has been divided by gender, which is the reason why possibility to choose has not been good enough to educationalists of equality. The latest guidelines for the National core curriculum for bacis education were issued in 2004. According to curriculum craft education consists parts of both technical and textile craft. All students should take part in both sectors of crafts. Furthermore, one can be given a possibility to consentrate his studies in whether textile or technical craft. The curriculum does not set the rules how the education should be organised, which means that it can be organised in many ways depending on city, school or teacher. Teachers and other specialists have contradictory feelings towards shared craft education, because traditional way to see craft in Finland is to separate textile craft from technical craft. Both crafts have some common features that are introduced in curriculum. Besides there is many equal things in craft theories that bind textile and technical craft to each other. The main purpose of this research was to find out, how shared craft education has been organised at the 7.th grade in Finnish comprehensive school, and which things affect in the settlements. Second goal was to describe and compare teachers´ experiences in teaching shared craft education. Third aim of this study was how shared craft has changed craft education. I collected the research material in May 2006 by interviewing both textile and technical craft teachers who teach shared craft. The material consists of fourteen theme interviews. In the analysis of the material I used theoretic bounded document analysis. According to the research there are three different ways to organise shared craft education: 50 50-arrangement, exchanging period and project week. In the schools that carried out 50 50-arrangement teaching was realised mainly in heterogenous groups. Principals had usual a lot of authorization on how to arrange craft education, which means that their views on equality, laws and curriculum affected in the settlemets more than teachers´ opinions. Teachers´ attitudes to shared craft were mainly positive. The changing of craft education can be divided in two parts: the aims and the containings of the curriculum have changed, as well as the meaning of the craft as core subject. Teachers have been forced to decrease the containings of both textile and technical crafts. Despite of eliminations both crafts still have comprehensive containings. Teachers decided what to teach by these argumets: Students should learn some basic things or produce a certain product. Usually teachers had also a lot of experience and special intrests in crafts. According to this research there is four significant meanings for shared craft education: 1) developing readiness for doing things, 2) developing skills of thinking, 3) delight of doing things and 4) teaching attitude.

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Aims: The aims of this study were 1) to identify and describe health economic studies that have used quality-adjusted life years (QALYs) based on actual measurements of patients' health-related quality of life (HRQoL); 2) to test the feasibility of routine collection of health-related quality of life (HRQoL) data as an indicator of effectiveness of secondary health care; and 3) to establish and compare the cost-utility of three large-volume surgical procedures in a real-world setting in the Helsinki University Central Hospital, a large referral hospital providing secondary and tertiary health-care services for a population of approximately 1.4 million. Patients and methods: So as to identify studies that have used QALYs as an outcome measure, a systematic search of the literature was performed using the Medline, Embase, CINAHL, SCI and Cochrane Library electronic databases. Initial screening of the identified articles involved two reviewers independently reading the abstracts; the full-text articles were also evaluated independently by two reviewers, with a third reviewer used in cases where the two reviewers could not agree a consensus on which articles should be included. The feasibility of routinely evaluating the cost-effectiveness of secondary health care was tested by setting up a system for collecting HRQoL data on approximately 4 900 patients' HRQoL before and after operative treatments performed in the hospital. The HRQoL data used as an indicator of treatment effectiveness was combined with diagnostic and financial indicators routinely collected in the hospital. To compare the cost-effectiveness of three surgical interventions, 712 patients admitted for routine operative treatment completed the 15D HRQoL questionnaire before and also 3-12 months after the operation. QALYs were calculated using the obtained utility data and expected remaining life years of the patients. Direct hospital costs were obtained from the clinical patient administration database of the hospital and a cost-utility analysis was performed from the perspective of the provider of secondary health care services. Main results: The systematic review (Study I) showed that although QALYs gained are considered an important measure of the effectiveness of health care, the number of studies in which QALYs are based on actual measurements of patients' HRQoL is still fairly limited. Of the reviewed full-text articles, only 70 reported QALYs based on actual before after measurements using a valid HRQoL instrument. Collection of simple cost-effectiveness data in secondary health care is feasible and could easily be expanded and performed on a routine basis (Study II). It allows meaningful comparisons between various treatments and provides a means for allocating limited health care resources. The cost per QALY gained was 2 770 for cervical operations and 1 740 for lumbar operations. In cases where surgery was delayed the cost per QALY was doubled (Study III). The cost per QALY ranges between subgroups in cataract surgery (Study IV). The cost per QALY gained was 5 130 for patients having both eyes operated on and 8 210 for patients with only one eye operated on during the 6-month follow-up. In patients whose first eye had been operated on previous to the study period, the mean HRQoL deteriorated after surgery, thus precluding the establishment of the cost per QALY. In arthroplasty patients (Study V) the mean cost per QALY gained in a one-year period was 6 710 for primary hip replacement, 52 270 for revision hip replacement, and 14 000 for primary knee replacement. Conclusions: Although the importance of cost-utility analyses has during recent years been stressed, there are only a limited number of studies in which the evaluation is based on patients own assessment of the treatment effectiveness. Most of the cost-effectiveness and cost-utility analyses are based on modeling that employs expert opinion regarding the outcome of treatment, not on patient-derived assessments. Routine collection of effectiveness information from patients entering treatment in secondary health care turned out to be easy enough and did not, for instance, require additional personnel on the wards in which the study was executed. The mean patient response rate was more than 70 %, suggesting that patients were happy to participate and appreciated the fact that the hospital showed an interest in their well-being even after the actual treatment episode had ended. Spinal surgery leads to a statistically significant and clinically important improvement in HRQoL. The cost per QALY gained was reasonable, at less than half of that observed for instance for hip replacement surgery. However, prolonged waiting for an operation approximately doubled the cost per QALY gained from the surgical intervention. The mean utility gain following routine cataract surgery in a real world setting was relatively small and confined mostly to patients who had had both eyes operated on. The cost of cataract surgery per QALY gained was higher than previously reported and was associated with considerable degree of uncertainty. Hip and knee replacement both improve HRQoL. The cost per QALY gained from knee replacement is two-fold compared to hip replacement. Cost-utility results from the three studied specialties showed that there is great variation in the cost-utility of surgical interventions performed in a real-world setting even when only common, widely accepted interventions are considered. However, the cost per QALY of all the studied interventions, except for revision hip arthroplasty, was well below 50 000, this figure being sometimes cited in the literature as a threshold level for the cost-effectiveness of an intervention. Based on the present study it may be concluded that routine evaluation of the cost-utility of secondary health care is feasible and produces information essential for a rational and balanced allocation of scarce health care resources.

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The basis for this study was in poor attractiveness of the wood products industry among young people as a field to study and work in. The purpose was to produce new information of how to improve the relationship between young people and the wood products industry in order to better attract young people with different relational orientation. A survey was conducted among students of comprehensive schools and students of wood industry at vocational schools selected by systematic cluster sampling. The final sample consisted of 613 students. The study combined the theories and concepts of relationships, communication and trust of several disciplines. In addition, it applied theories of relationship marketing, stakeholders, publics, involvement and concepts of reputation and values. It studied the central relational elements in the form of antecedents, relationship state and its consequences. The study examined, how young people with different background and level of interest perceive wood industry as a field to study and work in from relational point of view, what are the central deficiencies in perceived relational elements and what are the public relations activities enhancing the relationship between wood industry and young people with less and high interest in the sector. The results indicate poor visibility of the wood industry among young people: unfamiliarity with the industry and unawareness of the opportunities to study in the field. It appeared that instead of increasing only information sharing, interactive communication in different forms is needed. The study also suggests that behaviors of the industry sector advancing perceived trustworthiness are of crucial importance. Moreover, the wood industry needs to pay attention to its behaviors and communication also among other stakeholder groups, especially the media, as reputation plays an important role in building up trust and satisfaction between young people and the sector. Finally, the less and highly interested young people were found to assess the relationship partly through different relational elements. In order to develop the relationship with highly interested young people they should be regarded clearly as future employees of the wood industry through activities affirming that they are desired and valued employees in the sector. Further, openness of information disclosure, whether concerning current situation or future prospects, seems to increase credibility and attractiveness of the wood industry. Highly interested young people were also found to appreciate socially responsible activities. The less interested young people seem to be insecure about the reliability of the wood industry as an employer, as well as, its ability and interest to invest in young people s skills. In addition,involvement in issues relevant for young people was found crucial in enhancing the relationship with the less interested young people.The conclusions of the study provide tools for enhancing the attractiveness of the wood industry among young people not only to the industry itself, but also to its advocates, teachers and student counselors of comprehensive and vocational schools, authorities and policy makers.

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Tutkimuksen tavoitteena on historiantutkimuksen menetelmiä käyttäen selvittää metsänhoidon teorian sekä käytännön metsänhoidon kehitysvaiheet ja näihin vaikuttaneet tekijät, keskiajalta lähtien 1870-luvulla tapahtuneeseen metsäteollisuuden läpimurtoon saakka. Tutkimus tarkastelee Suomen metsiä, niiden käyttöä ja metsänhoidon alkuvaiheita Ruotsin ja Venäjän vallan aikoina. Vastauksia haetaan erityisesti seuraaviin pääkysymyksiin: - miten eri metsänkäyttömuodot ja -käyttäjät vaikuttivat metsiin ja metsänhoidon edistymiseen? - millä tavoin maanomistuksen kehitys vaikutti metsien käyttöön ja hoitoon? - millaisiin päämääriin ja yhteiskunnallisiin taustatekijöihin metsien käytön julkinen ohjaus perustui? - mitä käytännön vaikutuksia valtion metsäpolitiikalla ja ohjauksella oli metsänhoidon kehitykseen? - missä ja miten kehittyivät Suomessa sovellettu metsänhoidon teoria ja käytännön menetelmät? - mitkä tekijät säätelivät metsänhoidon teorioiden soveltamista käytäntöön? - mikä oli naapurimaiden metsänhoidon sekä kansainvälisten yhteyksien merkitys metsänhoidon kehitykselle Suomessa? - miten vuosisatainen pelko metsien ja puun loppumisesta vaikutti metsänhoidon kehitykseen? - millainen merkitys puun arvon kehityksellä oli metsänhoidon alkuun saattamiselle ja edistymiselle? Suomessa harjoitettiin 1870-luvulle saakka pääasiassa talonpoikaista metsänkäyttöä. Maaseudun väestö hankki toimeentulonsa metsistä eränkäynnin, kaskiviljelyn, laiduntamisen, rakennushirsien valmistamisen, tervantuotannon ja paikoin myös potaskan tai sysien valmistamisen avulla. Erityisesti rannikkoseuduilla tuotettiin "isorakennuksen puita", lehtereitä, mastopuita ja muuta erikoispuutavaraa. Lautojen ja lankkujen sahaus laajeni vähitellen, saavuttaen 1800-luvun lopulla hallitsevan aseman myyntiin tarkoitettujen metsäntuotteiden tuotannossa. Polttopuun sekä muun kotitarvepuun kulutus säilyi suurimpana puunkäytön ryhmänä pitkälle 1900-luvulle saakka. Mainituista metsänkäyttömuodoista erityisesti kaskeaminen ja sitä seuraava laiduntamisvaihe sekä tervaspuiden koloaminen "autioittivat" laajoja metsäalueita. Tiheimmin asutuilla seuduilla esiintyi pulaa poltto- ja rakennuspuusta myöhäiskeskiajalta alkaen. Nämä ongelmat sekä laivanrakennuksen ja vuoriteollisuuden puunsaannin turvaamisen tarve johtivat 1600-luvun puolivälissä pysyvään metsänkäytön julkiseen ohjaukseen. Tuolloin Ruotsin valtakunnan metsälainsäädännön kivijalaksi tuli kestävyyden periaate, josta kruunu kylläkin joutui tinkimään moneen otteeseen. Valtion jatkuva rahantarve oli käytännössä metsäpolitiikan tärkein taustavoima sekä Ruotsin vallan että autonomian aikana. Jo 1600-luvulla ruvettiin vaatimaan talonpoikien yhteismaiden jakamista omistajilleen vastuullisemman metsänkäytön nimissä. Isoajakoa saatiin Suomessa odottaa 1770-luvulle saakka. Etelä-Suomessa se valmistui melko nopeasti, 1800-luvun puoliväliin mennessä. Sillä olikin myönteinen, metsien säästävämpään käsittelyyn johtava vaikutus. Valtiosta tuli isonjaon myötä erityisesti Pohjois-Suomessa merkittävä metsänomistaja 1800-luvun jälkipuoliskolla. Valtion metsähallinto, jota maaherrat ja sivistyneistö vaativat perustettavaksi jo 1700-luvun puolivälissä, aloitti toimintansa maanlaajuisesti 1860-luvulla. Se oli ensimmäinen merkittävä metsänhoidon organisaatio, ja vasta sen myötä metsänkäyttöä ohjaavilla säädöksillä ja ohjeilla alkoi olla käytännön merkitystä. Yksityismetsiä varten ei tällaista organisaatiota vielä perustettu, niitä rasittivat pahoin nousevan sahateollisuuden määrämittahakkuut pitkälle 1900-luvun puolelle. Turun Akatemiassa tehtiin mittavaa metsänhoidon menetelmiä koskevaa sekä myös metsäpoliittista tutkimustyötä 1700-luvun jälkipuoliskolla. Tulokset eivät vielä sanottavasti siirtyneet käytäntöön, lähinnä puun alhaisen arvon ja tarvittavien organisaatioiden puuttumisen takia. Kun valtion metsähallintoa ja Suomen omaa metsäopetusta ryhdyttiin perustamaan 1800-luvun puolivälissä, haettiin metsänhoidon mallia alan johtavaksi maaksi kehittyneestä Saksasta. Tultaessa 1870-luvulle, oli Evolla jo käynnissä voimakas kehitystyö maamme olosuhteisiin soveltuvien menetelmien luomiseksi saksalaisen teorian pohjalta. Metsänhoidon tiedot ja taidot olisivat jo tässä vaiheessa riittäneet kestävän metsätalouden harjoittamiseen kaikkien omistajaryhmien metsissä, jos tarvittavat organisaatiot olisi kyetty perustamaan ja metsäammattilaisia olisi koulutettu tarpeeksi. Metsänhoidon kehitystä hidastivat 1800-luvun lopulla lähinnä valtion heikko talous ja poliittiset näkemyserot. Metsäteollisuuden 1870-luvulta alkanut voimakas kasvu ja lisääntyvä puuntarve pakottivat kuitenkin valtiovallan pitämään huolta puuntuotannon jatkuvuudesta. Metsäteollisuuden kasvavan viennin kautta lisääntyvät verotulot ja kan-santalouden myönteinen kehitys antoivat vähitellen mahdollisuuden metsänhoidon edistämiseen ammattilaisten koulutuksen, kansalaisten neuvonnan, lainsäädännön ja viranomaisten toiminnan kautta. Tämä tutkimus lähestyy aihettaan metsähistorian, taloushistorian, yhteiskuntahistorian ja ympäristöhistorian näkökulmista. Ajankohtaista merkitystä sillä on kehitysmaiden sekä Itä-Euroopan siirtymätalouksien metsänhoidon edistämiselle, missä suomalaiset metsäammattilaiset ovat mukana lukuisten kehityshankkeiden asiantuntijoina. Kymmenissä maissa metsätalous kamppailee samanlaisten ongelmien kanssa kuin Suomessa ja naapurimaissa 100 - 300 vuotta sitten. Meidän kokemuksistamme on näille kansantalouksille hyötyä valtion- ja yksityismetsätalouden metsänhoito-organisaatioita sekä metsälainsäädäntöä kehitettäessä.

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The United States is the world s single biggest market area, where the demand for graphic papers has increased by 80 % during the last three decades. However, during the last two decades there have been very big unpredictable changes in the graphic paper markets. For example, the consumption of newsprint started to decline from the late 1980 s, which was surprising compared to the historical consumption and projections. The consumption has declined since. The aim of this study was to see how magazine paper consumption will develop in the United States until 2030. The long-term consumption projection was made using mainly two methods. The first method was to use trend analysis to see how and if the consumption has changed since 1980. The second method was to use qualitative estimate. These estimates are then compared to the so-called classical model projections, which are usually mentioned and used in forestry literature. The purpose of the qualitative analysis is to study magazine paper end-use purposes and to analyze how and with what intensity the changes in society will effect to magazine paper consumption in the long-term. The framework of this study covers theories such as technology adaptation, electronic substitution, electronic publishing and Porter s threat of substitution. Because this study deals with markets, which have showed signs of structural change, a very substantial part of this study covers recent development and newest possible studies and statistics. The following were among the key findings of this study. Different end-uses have very different kinds of future. Electronic substitution is very likely in some end-use purposes, but not in all. Young people i.e. future consumers have very different manners, habits and technological opportunities than our parents did. These will have substantial effects in magazine paper consumption in the long-term. This study concludes to the fact that the change in magazine paper consumption is more likely to be gradual (evolutionary) than sudden collapse (revolutionary). It is also probable that the years of fast growing consumption of magazine papers are behind. Besides the decelerated growth, the consumption of magazine papers will decline slowly in the long-term. The decline will be faster depending on how far in the future we ll extend the study to.

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Department of Forest Resource Management in the University of Helsinki has in years 2004?2007 carried out so-called SIMO -project to develop a new generation planning system for forest management. Project parties are organisations doing most of Finnish forest planning in government, industry and private owned forests. Aim of this study was to find out the needs and requirements for new forest planning system and to clarify how parties see targets and processes in today's forest planning. Representatives responsible for forest planning in each organisation were interviewed one by one. According to study the stand-based system for managing and treating forests continues in the future. Because of variable data acquisition methods with different accuracy and sources, and development of single tree interpretation, more and more forest data is collected without field work. The benefits of using more specific forest data also calls for use of information units smaller than tree stand. In Finland the traditional way to arrange forest planning computation is divided in two elements. After updating the forest data to present situation every stand unit's growth is simulated with different alternative treatment schedule. After simulation, optimisation selects for every stand one treatment schedule so that the management program satisfies the owner's goals in the best possible way. This arrangement will be maintained in the future system. The parties' requirements to add multi-criteria problem solving, group decision support methods as well as heuristic and spatial optimisation into system make the programming work more challenging. Generally the new system is expected to be adjustable and transparent. Strict documentation and free source code helps to bring these expectations into effect. Variable growing models and treatment schedules with different source information, accuracy, methods and the speed of processing are supposed to work easily in system. Also possibilities to calibrate models regionally and to set local parameters changing in time are required. In future the forest planning system will be integrated in comprehensive data management systems together with geographic, economic and work supervision information. This requires a modular method of implementing the system and the use of a simple data transmission interface between modules and together with other systems. No major differences in parties' view of the systems requirements were noticed in this study. Rather the interviews completed the full picture from slightly different angles. In organisation the forest management is considered quite inflexible and it only draws the strategic lines. It does not yet have a role in operative activity, although the need and benefits of team level forest planning are admitted. Demands and opportunities of variable forest data, new planning goals and development of information technology are known. Party organisations want to keep on track with development. One example is the engagement in extensive SIMO-project which connects the whole field of forest planning in Finland.

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A View into the World of Kitchen: Development and retention of a leading position in the market of kitchen interiors - a case study of 20 years. This study focuses on the development of a kitchen interiors company, presently called Novart Inc., into the leading company of the industry from 1980´s to the present. The objective of the study is to describe the effects of strategic choices, the decisions of the management and the owner´s direction and control to the build up and the retaining of the leading position in the market. From theory point of view, strategic choices refer to com-pany purchases as corporate-level strategies, and business and marketing strategies. The empirical research was carried out in two phases and it is based on various company documents and records, and on the intensive interviews of seven key executives in the company. An abductive research design was utilized. The company gained the leading position in the kitchen market in Finland by company purchases, and the company has been able to retain the position. Firstly the goal was to expand to retail market and, secondly, the company has maintained the balance of supply and demand by closing the purchased production units when needed. The simultaneous use of these two strategic goals is a kind of a new observation, and the strategy may be suitable only for market leaders. During the latter part of the research period the strategy of com-pany purchases has been abandoned and the leading position in the market has been main-tained by developing systematically business and marketing capability. In the business and marketing strategies the distribution channels and the brands have been emphasized. During the research period the company has almost totally abandoned the long distribution channels and started to use its own channels built and named after the main brands. These are A la Carte, Parma and Petra. At the moment, in the beginning of the 21st century, a new distribution channel, the concept of the Kitchen World, is being built in addition to the channels mentioned above. The management´s decision making and the implementation the decisions have been well-considered. The executives emphasized the valuing of the importance of the decisions dif-ferently except the two decisions named the most important ones, i.e., the decisions to start own production of the raw material and to concentrate the business only to one company. The executive staff has also succeeded in managing crisis and threats of bankruptcy, and the company has been managed profitable. During all the four terms of ownership: Puolimatka Corporation, the Hankkija/Novera Corporation, the ownership period of the "bank", and the Nobia Corporate the ownership direction and control has been somewhat different. All the owners have paid attention to economic issues. The direction of cash flows and investments was at its strongest during the Hankkija/Novera term. For the last owner Nobia the production and marketing of the kitchen interiors has been the core business, which thus has strengthened the business and marketing capabilities of the target company of this research. A common denominator during all the four terms of ownership has been owners' trust gained by the professional skills of the management of the target company. This has lead to greater independence of the management of the company and less owners´ direction. Keywords: leading position, marketing strategy, management decisions, acquisition, corporate governance

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Thin films of various metal fluorides are suited for optical coatings from infrared (IR) to ultraviolet (UV) range due to their excellent light transmission. In this work, novel metal fluoride processes have been developed for atomic layer deposition (ALD), which is a gas phase thin film deposition method based on alternate saturative surface reactions. Surface controlled self-limiting film growth results in conformal and uniform films. Other strengths of ALD are precise film thickness control, repeatability and dense and pinhole free films. All these make the ALD technique an ideal choice also for depositing metal fluoride thin films. Metal fluoride ALD processes have been largely missing, which is mostly due to a lack of a good fluorine precursor. In this thesis, TiF4 precursor was used for the first time as the fluorine source in ALD for depositing CaF2, MgF2, LaF3 and YF3 thin films. TaF5 was studied as an alternative novel fluorine precursor only for MgF2 thin films. Metal-thd (thd = 2,2,6,6-tetramethyl-3,5-heptanedionato) compounds were applied as the metal precursors. The films were grown at 175 450 °C and they were characterized by various methods. The metal fluoride films grown at higher temperatures had generally lower impurity contents with higher UV light transmittances, but increased roughness caused more scattering losses. The highest transmittances and low refractive indices below 1.4 (at 580 nm) were obtained with MgF2 samples. MgF2 grown from TaF5 precursor showed even better UV light transmittance than MgF2 grown from TiF4. Thus, TaF5 can be considered as a high quality fluorine precursor for depositing metal fluoride thin films. Finally, MgF2 films were applied in fabrication of high reflecting mirrors together with Ta2O5 films for visible region and with LaF3 films for UV region. Another part of the thesis consists of applying already existing ALD processes for novel optical devices. In addition to the high reflecting mirrors, a thin ALD Al2O3 film on top of a silver coating was proven to protect the silver mirror coating from tarnishing. Iridium grid filter prototype for rejecting IR light and Ir-coated micro channel plates for focusing x-rays were successfully fabricated. Finally, Ir-coated Fresnel zone plates were shown to provide the best spatial resolution up to date in scanning x-ray microscopy.

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This thesis consists of an introduction, four research articles and an appendix. The thesis studies relations between two different approaches to continuum limit of models of two dimensional statistical mechanics at criticality. The approach of conformal field theory (CFT) could be thought of as the algebraic classification of some basic objects in these models. It has been succesfully used by physicists since 1980's. The other approach, Schramm-Loewner evolutions (SLEs), is a recently introduced set of mathematical methods to study random curves or interfaces occurring in the continuum limit of the models. The first and second included articles argue on basis of statistical mechanics what would be a plausible relation between SLEs and conformal field theory. The first article studies multiple SLEs, several random curves simultaneously in a domain. The proposed definition is compatible with a natural commutation requirement suggested by Dubédat. The curves of multiple SLE may form different topological configurations, ``pure geometries''. We conjecture a relation between the topological configurations and CFT concepts of conformal blocks and operator product expansions. Example applications of multiple SLEs include crossing probabilities for percolation and Ising model. The second article studies SLE variants that represent models with boundary conditions implemented by primary fields. The most well known of these, SLE(kappa, rho), is shown to be simple in terms of the Coulomb gas formalism of CFT. In the third article the space of local martingales for variants of SLE is shown to carry a representation of Virasoro algebra. Finding this structure is guided by the relation of SLEs and CFTs in general, but the result is established in a straightforward fashion. This article, too, emphasizes multiple SLEs and proposes a possible way of treating pure geometries in terms of Coulomb gas. The fourth article states results of applications of the Virasoro structure to the open questions of SLE reversibility and duality. Proofs of the stated results are provided in the appendix. The objective is an indirect computation of certain polynomial expected values. Provided that these expected values exist, in generic cases they are shown to possess the desired properties, thus giving support for both reversibility and duality.

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Planar curves arise naturally as interfaces between two regions of the plane. An important part of statistical physics is the study of lattice models. This thesis is about the interfaces of 2D lattice models. The scaling limit is an infinite system limit which is taken by letting the lattice mesh decrease to zero. At criticality, the scaling limit of an interface is one of the SLE curves (Schramm-Loewner evolution), introduced by Oded Schramm. This family of random curves is parametrized by a real variable, which determines the universality class of the model. The first and the second paper of this thesis study properties of SLEs. They contain two different methods to study the whole SLE curve, which is, in fact, the most interesting object from the statistical physics point of view. These methods are applied to study two symmetries of SLE: reversibility and duality. The first paper uses an algebraic method and a representation of the Virasoro algebra to find common martingales to different processes, and that way, to confirm the symmetries for polynomial expected values of natural SLE data. In the second paper, a recursion is obtained for the same kind of expected values. The recursion is based on stationarity of the law of the whole SLE curve under a SLE induced flow. The third paper deals with one of the most central questions of the field and provides a framework of estimates for describing 2D scaling limits by SLE curves. In particular, it is shown that a weak estimate on the probability of an annulus crossing implies that a random curve arising from a statistical physics model will have scaling limits and those will be well-described by Loewner evolutions with random driving forces.

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Quasiconformal mappings are natural generalizations of conformal mappings. They are homeomorphisms with 'bounded distortion' of which there exist several approaches. In this work we study dimension distortion properties of quasiconformal mappings both in the plane and in higher dimensional Euclidean setting. The thesis consists of a summary and three research articles. A basic property of quasiconformal mappings is the local Hölder continuity. It has long been conjectured that this regularity holds at the Sobolev level (Gehring's higher integrabilty conjecture). Optimal regularity would also provide sharp bounds for the distortion of Hausdorff dimension. The higher integrability conjecture was solved in the plane by Astala in 1994 and it is still open in higher dimensions. Thus in the plane we have a precise description how Hausdorff dimension changes under quasiconformal deformations for general sets. The first two articles contribute to two remaining issues in the planar theory. The first one concerns distortion of more special sets, for rectifiable sets we expect improved bounds to hold. The second issue consists of understanding distortion of dimension on a finer level, namely on the level of Hausdorff measures. In the third article we study flatness properties of quasiconformal images of spheres in a quantitative way. These also lead to nontrivial bounds for their Hausdorff dimension even in the n-dimensional case.

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Delay and disruption tolerant networks (DTNs) are computer networks where round trip delays and error rates are high and disconnections frequent. Examples of these extreme networks are space communications, sensor networks, connecting rural villages to the Internet and even interconnecting commodity portable wireless devices and mobile phones. Basic elements of delay tolerant networks are a store-and-forward message transfer resembling traditional mail delivery, an opportunistic and intermittent routing, and an extensible cross-region resource naming service. Individual nodes of the network take an active part in routing the traffic and provide in-network data storage for application data that flows through the network. Application architecture for delay tolerant networks differs also from those used in traditional networks. It has become feasible to design applications that are network-aware and opportunistic, taking an advantage of different network connection speeds and capabilities. This might change some of the basic paradigms of network application design. DTN protocols will also support in designing applications which depend on processes to be persistent over reboots and power failures. DTN protocols could also be applicable to traditional networks in cases where high tolerance to delays or errors would be desired. It is apparent that challenged networks also challenge the traditional strictly layered model of network application design. This thesis provides an extensive introduction to delay tolerant networking concepts and applications. Most attention is given to challenging problems of routing and application architecture. Finally, future prospects of DTN applications and implementations are envisioned through recent research results and an interview with an active researcher of DTN networks.

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This study in church history deals with the formation of aims in the church politics of the Centre Party during a period of extensive politicisation in Finnish society – 1966 to 1978. The focus is on the processes of creating political input within the party organisation. The most important source material consists of the records of the highest party organs as well as material from the party office and the party’s committee for church politics. In the late 1960s, at a time of leftist radicalism in Finnish society, issues concerning the Church were seldom dealt with in the highest party organs, even though informal discussion took place within the party. This phase was followed by a conservative reaction in society during the 1970s. The rightist trend as well as the ongoing politicisation process substantially strengthened the role of church politics in the party. An aim of great importance was to prevent those supporters who belonged to the Lutheran revival movements from moving into the Finnish Christian League. Therefore it became increasingly important to prove that the Centre Party was defending the Church as well as so-called Christian values in state politics, e.g., by advocating religious instruction in schools. The Centre Party also defended the independence and legal status of the Church, at the same time positioning itself against Finland’s Social Democratic Party. Many party members were of the opinion that the church politics should have been about defending the Church and Christian values in state politics instead of defending the proportional share of the party’s seats in the ecclesiastical decision-making system. Nevertheless, the struggle for hegemony between the Centre Party and the Social Democrats was reflected in the Evangelical Lutheran Church particularly since 1973. Thus the aims of church politics were increasingly directed towards ecclesiastical elections and appointments in the 1970s. To justify its activities in church elections, the party stressed that it was not politicising the Church. To the contrary, it was asserted that the church leaders themselves had politicised the Church by favouring the Social Democrats. These alleged efforts to affiliate the Church with one political party were strictly condemned in the Centre Party. But when it came to the political parties’ activity in church elections, opinions diverged. Generally, the issues of church politics resembled those of the party’s trade union politics in the 1970s.

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The aim of the study was to analyse Church Youth Work Leader students different processes of developing their spirituality and professional identity. The study was carried out in connection with the church-orientated education at the Diaconia University of Applied Sciences (Diak). The method of the study was narrative analysis. The data consisted of stories written (N=46) and told (N=10) by students, that were collected over three years in two units of Diak. The data was analysed in two ways: first with categorical-content analysis, and then with holistic-content analysis and holistic-form reading in order to establish the comprehensive views of complete narratives. The theoretical starting-point was to regard spirituality widely, including religion and faith. In the first data analysis, this theory was focused so that spirituality was namely Christian spirituality including personal faith and worship, membership in the Christian community and persons values and ideas about the meaning of life. The results of the investigation were presented in five model narratives. The story of a social care worker represents the process of a student orientating to social work. In this story spirituality manifested as a part of social and personal identity but not as a part of professional identity. The vocation for helping people led the student to social care work. In the story of a counselor, students good connection to their home parish took a central role. They had good experiences working as young Christian volunteers, and during their studies this volunteer role became professional role. Spirituality was strongly joined to professional identity. The story of an educator represents a vocation for spiritual work and youth work in the church. In this story students also had good connections to their home parishes. Spirituality manifested as a part of personal, social and professional identity. In the story of a spiritual worker or preacher, each person s spiritual vocation was remarkable. Spirituality was extremely individual and it defined the personal, social and professional identity. Spiritual devotion caused a change in students orientation from the church to social services. The story of a searcher tells about a student who is still looking for her or his own profession. The focus of the story was on personal growth and considering one s values and the meaning of life. Spirituality was manifested in personal identity. The results indicate that the practical placements in the second academic year have an important effect on students professional orientation and professional identity. The connection to the local parish has also significant meaning for students spiritual formation and development into church professions.

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Volatility is central in options pricing and risk management. It reflects the uncertainty of investors and the inherent instability of the economy. Time series methods are among the most widely applied scientific methods to analyze and predict volatility. Very frequently sampled data contain much valuable information about the different elements of volatility and may ultimately reveal the reasons for time varying volatility. The use of such ultra-high-frequency data is common to all three essays of the dissertation. The dissertation belongs to the field of financial econometrics. The first essay uses wavelet methods to study the time-varying behavior of scaling laws and long-memory in the five-minute volatility series of Nokia on the Helsinki Stock Exchange around the burst of the IT-bubble. The essay is motivated by earlier findings which suggest that different scaling laws may apply to intraday time-scales and to larger time-scales, implying that the so-called annualized volatility depends on the data sampling frequency. The empirical results confirm the appearance of time varying long-memory and different scaling laws that, for a significant part, can be attributed to investor irrationality and to an intraday volatility periodicity called the New York effect. The findings have potentially important consequences for options pricing and risk management that commonly assume constant memory and scaling. The second essay investigates modelling the duration between trades in stock markets. Durations convoy information about investor intentions and provide an alternative view at volatility. Generalizations of standard autoregressive conditional duration (ACD) models are developed to meet needs observed in previous applications of the standard models. According to the empirical results based on data of actively traded stocks on the New York Stock Exchange and the Helsinki Stock Exchange the proposed generalization clearly outperforms the standard models and also performs well in comparison to another recently proposed alternative to the standard models. The distribution used to derive the generalization may also prove valuable in other areas of risk management. The third essay studies empirically the effect of decimalization on volatility and market microstructure noise. Decimalization refers to the change from fractional pricing to decimal pricing and it was carried out on the New York Stock Exchange in January, 2001. The methods used here are more accurate than in the earlier studies and put more weight on market microstructure. The main result is that decimalization decreased observed volatility by reducing noise variance especially for the highly active stocks. The results help risk management and market mechanism designing.