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Conformal blocks are building blocks of correlation functions in conformal field theories (CFTs). They neatly encode the universal information dictated by conformal symmetry and separate it from the dynamical information which depends on the particular theory. Conformal blocks merit an in-depth study as is evidenced by their extensive applications in the study of bulk locality in the AdS/CFT correspondence and the recent conformal bootstrap program. The vacuum Virasoro blocks in the semi-classical (large central charge) limit is known to compute the leading order contribution to the Rényi entropy. Moreover, the semi-classical Virasoro blocks along with conformal bootstrap feature in a proof of the cluster decomposition principle for AdS3/CFT2. In this thesis, conformal field theory and its necessary ingredients are briefly reviewed. Conformal blocks from the exchange of a spinless operator are evaluated by holographic computations of geodesic Witten diagrams for AdSd+1/CFTd. The results are verified against the Casimir operator method of Dolan and Osborn. Virasoro blocks in various semi-classical limits are discussed, and holographic Virasoro blocks are calculated in the global, heavy-light, and perturbative heavy, and the results are verified using the monodromy method. Finally, defect conformal field theories (dCFTs) are introduced and, as an original contribution, an integral expression for defect conformal blocks is obtained, which is expected to precisely match the corresponding result in dCFT literature.

Tutkielmassa tarkastellaan semi-Markov-prosessin hyödyntämistä keskeyttämistapahtuman mallintamiseksi vapaaehtoisessa henkivakuutuksessa. Vakuutetun riskin kehitys mallinnetaan monitilaisena semi-Markov-prosessina ja keskeyttämisintensiteetti määritellään tähän pohjautuvan vakuutusmaksun ja klassisen henkivakuutusteorian mukaisen vakuutusmaksun funktiona. Keskeyttämisintensiteetti asetetaan riippumaan lisäksi lineaarisesti keskeyttämisherkkyydeksi tulkitusta vakiosta. Numeerisena esimerkkinä simuloidaan vakuutuskannan kehitystä eri keskeyttämisherkkyyksin ja tarkastellaan aktiivisen kannan koostumusta simulointijakson jälkeen.

In this thesis a manifold learning method is applied to the problem of WLAN positioning and automatic radio map creation. Due to the nature of WLAN signal strength measurements, a signal map created from raw measurements results in non-linear distance relations between measurement points. These signal strength vectors reside in a high-dimensioned coordinate system. With the help of the so called Isomap-algorithm the dimensionality of this map can be reduced, and thus more easily processed. By embedding position-labeled strategic key points, we can automatically adjust the mapping to match the surveyed environment. The environment is thus learned in a semi-supervised way; gathering training points and embedding them in a two-dimensional manifold gives us a rough mapping of the measured environment. After a calibration phase, where the labeled key points in the training data are used to associate coordinates in the manifold representation with geographical locations, we can perform positioning using the adjusted map. This can be achieved through a traditional supervised learning process, which in our case is a simple nearest neighbors matching of a sampled signal strength vector. We deployed this system in two locations in the Kumpula campus in Helsinki, Finland. Results indicate that positioning based on the learned radio map can achieve good accuracy, especially in hallways or other areas in the environment where the WLAN signal is constrained by obstacles such as walls.

Calculating sentence similarities is an essential task for natural language processing. It allows for implementing similarity searches, where the most similar sentence is found out of many for some query sentence, it allows for clustering text by semantic meaning, and finally, sentence embeddings, which are used for calculating the similarities, can also be used as input for any text classification models. There is much room for improvement in sentence embedding model architectures and training methods, both in terms of accuracy and training efficiency. This thesis experiments with a novel unsupervised training method called Sentence Embeddings via Token Inference (SETI), which is efficient by design, to see if it can compete with other methods in accuracy. Using the same data, our experiments train SETI and three other existing training methods: TSDAE, QuickThoughts, and generic MLM. We then compare these models to each other in different sentence similarity and downstream classification tasks. Based on our experiments, SETI is comparable to TSDAE in sentence similarity tasks and better than generic MLM and QuickThoughts training methods in sentence similarity tasks. However, TSDAE has the highest accuracy for downstream classification tasks, while SETI still beats the generic MLM and QuickThoughts models.

Improving employee well-being is a key part of pension agency Keva’s mission statement. Recently, Keva has launched a tool for conducting repeated small-scale employee well-being surveys called ”Pulssi”. With the number of responses reaching thousands Keva has identified processing and organizing this data as a part of this process that could be improved using machine learning methods. In this thesis, we conducted a comprehensive investigation into using language models and sentiment classifications as a solution. We tested three different methodologies for this purpose, traditional machine learning with learned embeddings, generative language methods, and fine-tuned BERT models. To our knowledge, this is the first study evaluating the use of language models on the Finnish sentiment analysis task. Additionally, we evaluated the feasibility of implementing these methods based on their operating costs and the time it took to create classifications. We found that the traditional machine learning trained on learned embeddings performed surprisingly well, achieving an accuracy of 91%. These models offer a fast and cost-effective alternative to the more cumbersome language models. Our fine-tuned BERT model the ”KevaBERT” achieved an impressive accuracy of 93.6%, when trained on GPT-4 generated predictions, suggesting a potential pathway for training data creation. Overall our best performance was achieved by the ”GPT-4 few-shot with context” model at 93.9% accuracy. Our accuracies rival or even surpass the state-of-the-art accuracies achieved on other datasets. Despite the near human-level performance, this model was slow and expensive to operate. Based on these findings we recommend the use of our ”KevaBERT” model for sentiment classifications and a separate GPT-4 based model for text summarization.

Measurement of alpha-active actinides requires separation from other alpha emitting radionuclides. A method of actinide separation was needed for the primary coolant water of Loviisa Nuclear Power Plant. A method published by Eichrom Ltd was chosen to be evaluated, this method utilises a vacuum box with stacked TEVA / TRU columns which speeds up and eases the analysis process. The method can be used to separate americium, curium, plutonium and uranium from a water samples and it gave excellent results both with reference samples and primary coolant water. The separation was also tested with other more difficult matrices: ion exchange resins, surface swipes, aerosol filters and process waste waters. Pretreatment methods for these matrices were assessed and tested to reduce the sample to a soluble form that could be loaded to the separation system. DGA resin based methods were tested for both gross-alpha and nuclide specific analyses. The gross-alpha method with DGA was fast, efficient and reliant. Gross alpha counting samples could be produced within hours and element fraction samples could be produced in 1 - 2 days. This combined with the good recoveries of all fractions meant shorter counting times to reach the minimal detectable activities (MDAs) required. The literature review part takes a look into recent interesting topics related to actinide separation and analysis from similar matrices discussed in the the experimental section. Different extraction chromatography resins are discussed.

The ultramafic rocks in the Komati Complex, Barbeton greenstone belt, South Africa have been serpentinized thoroughly and carbonated with variable intensities. Conditions of the serpentinization and carbonation of the ultramafic rocks in the Komati Complex were studied using serpentine phase characterization by Raman spectroscopy, calcite hosted fluid inclusion microthermometry and chlorite geothermometry. Three serpentine phases, lizardite, chrysotile, and antigorite occur in four samples studied with Raman spectroscopy. Antigorite dominates the serpentine mineralogy in two of the samples and other two have large amounts of lizardite and antigorite, chrysotile being a minor constituent in three of the four samples. Abundant antigorite indicates serpentine crystallization above a temperature of ~ 320 °C. Fluid inclusion petrography and microthermometric data revealed four fluid inclusion assemblages (FIA), FIA 1 - FIA 4 in an order from earliest to latest entrapment. The FIAs have homogenization temperatures in the ranges of ~170 - 240 °C (FIA 1), 154 - 163 °C (FIA 2), 149 - 180 °C (FIA 3), 112 - 137 °C (FIA 4). Relatively constant NaCl equivalent salinities in the range of 6.4 - 11 wt-% were recorded for the FIAs 1 and 2, similar salinities were indicated for the FIAs 3 and 4. Chlorite geothermometry yielded temperatures in the approximate range of 150 - 250 °C. Chlorite crystallization is texturally indicated to be related to the formation of the calcite that hosts the fluid inclusions. The overlap of chlorite geothermometry temperatures and the homogenization temperatures of the earliest fluid inclusions (FIA 1) indicates fluid inclusion entrapment at pressures lower than 200 - 300 bar and at temperatures equal to or slightly above the recorded homogenization temperatures. These pressure and temperature estimations suggest that carbonation occurred in a seafloor environment at moderate hydrothermal conditions. The properties of carbonate hosted fluid inclusions resemble those of fluid inclusions reported from Archean greenstone belts and interpreted as Archean seawater by previous contributions. Calcite hosted fluid inclusions may, thus, represent entrapped Archean seawater.

The mobile phone has, as a device, taken the world by storm in the past decade; from only 136 million phones globally in 1996, it is now estimated that by the end of 2008 roughly half of the worlds population will own a mobile phone. Over the years, the capabilities of the phones as well as the networks have increased tremendously, reaching the point where the devices are better called miniature computers rather than simply mobile phones. The mobile industry is currently undertaking several initiatives of developing new generations of mobile network technologies; technologies that to a large extent focus at offering ever-increasing data rates. This thesis seeks to answer the question of whether the future mobile networks in development and the future mobile services are in sync; taking a forward-looking timeframe of five to eight years into the future, will there be services that will need the high-performance new networks being planned? The question is seen to be especially pertinent in light of slower-than-expected takeoff of 3G data services. Current and future mobile services are analyzed from two viewpoints; first, looking at the gradual, evolutionary development of the services and second, through seeking to identify potential revolutionary new mobile services. With information on both current and future mobile networks as well as services, a network capability - service requirements mapping is performed to identify which services will work in which networks. Based on the analysis, it is far from certain whether the new mobile networks, especially those planned for deployment after HSPA, will be needed as soon as they are being currently roadmapped. The true service-based demand for the 'beyond HSPA' technologies may be many years into the future - or, indeed, may never materialize thanks to the increasing deployment of local area wireless broadband technologies.

The thesis concentrates on to evaluate challenges in the business process management and the need for Service-oriented process models in telecommunication business to alleviate the integration work efforts and to reduce total costs of ownership. The business aspect concentrates on operations and business support systems which are tailored for communication service providers. Business processes should be designed in conformance with TeleManagement Forum's integrated business architecture framework. The thesis rationalizes the need to transform organizations and their way of working from vertical silos to horizontal layers and to understand transformational efforts which are needed to adopt a new strategy. Furthermore, the thesis introduces service characterizations and goes deeper into technical requirements that a service compliant middleware system needs to support. At the end of the thesis Nokia Siemens Networks proprietary approach – Process Automation Enabling Suite is introduced, and finally the thesis performs two case studies. The first one is Nokia Siemens Networks proprietary survey which highlights the importance of customer experience management and the second one is an overall research study whose results have been derived from other public surveys covering application integration efforts.

Tämä tutkielma käsittelee suomalaisten kaupunkien tekemää yhteisö- ja osallisuustyötä. Kaupungit ovat toteuttaneet jo useiden vuosikymmenien ajan erilaisia asukkaiden aktivoimiseen ja yhteisöllisyyden lisäämiseen tähtääviä projekteja, ja yhteisöllisyyden edistäminen on yleinen tavoite kaupunkien strategioissa. Strategiatasolla yhteisön ja yhteisöllisyyden käsitteet esiintyvät kuitenkin heikosti konkretisoituina. Lisäksi yhteisöllisyys oletetaan usein yksiselitteisen myönteiseksi ilmiöksi, vaikka alueellisen yhteisöllisyyden kääntöpuolena saattaa esiintyä esimerkiksi paikallista kontrollia, leimaamista ja syrjimistä. Kaupunkien yhteisöhankkeiden tavoitteiksi on määritelty mm. asuinalueen sosiaalisen koheesion edistäminen sekä asukkaiden mielialan kohentaminen erilaisten tapahtumien ja projektien kautta. Aiemmissa tutkimuksissa yhteisöhankkeita on kuitenkin tutkittu myös poliittisemmasta näkökulmasta. Yhteisöhankkeissa on nähty kiinnekohtia mm. kommunitarismia suosineeseen ”kolmannen tien” politiikkaan. Kommunitarismille ja kolmannen tien periaatteille tyypillisiä piirteitä ovat esim. puhtaasti valtiollisten ratkaisumallien sivuuttaminen ja moraalisesti vastuullisten paikallisyhteisöjen ennallistaminen. Kriittisen näkökulmasta paikallisyhteisöjen aktivointi on tulkittu yhteiskuntapoliittiseksi keinoksi, jolla on arvostelijoiden mukaan pyritty korvaamaan valtiollista sosiaalipoliittista järjestelmää. Tutkielmassa on analysoitu kaupunkien yhteisö- ja osallisuustyöstä vastaavien hankeasiantuntijoiden ajatuksia yhteisöllisyydestä ja sen mahdollisuuksista. Tutkimuskysymykseni ovat :1) Miten yhteisöllisyyttä nähdään syntyvän ja 2) millaisia vaikutuksia yhteisö- ja osallisuustyöllä halutaan tuottaa? Avaan työssäni sitä, mitä yhteisöllisyys haastatelluille hankeasiantuntijoille merkitsee, minkälaisiin ongelmiin yhteisöllisyyden pitäisi toimia ratkaisuna ja millä tavalla yhteisöllisyys nämä ongelmat ratkaisisi. Aineisto koostuu viidelle eri suomalaiskaupungille työskentelevien hankeasiantuntijoiden puolistrukturoiduista teemahaastatteluista (n=8), jotka on analysoitu teoriaohjaavalla sisällönanalyysillä. Analyysi nojaa affektiivisen kansalaisuuden (affective citizenship) käsitteeseen, joka kuvaa sitä tapaa, miten affektit ja kansalaisuus yhdistyvät biovaltaan ja hallinnallisuuteen. Kansalaisia saatetaan esimerkiksi rohkaista tuntemaan kiitollisuutta ja uskollisuutta kansakuntaa kohtaan ja toisten tunteiden oikeutus saatetaan tunnustaa enemmän kuin toisten. Analyysin tukena on käytetty myös yhteisön ja sosiaaliseen pääoman käsitteisiin liittyviä teorianäkökulmia sekä Mark Granovetterin (1973) heikkojen siteiden teoriaa. Tutkimustulosten mukaan kaupunkien yhteisö- ja osallisuustyötä voi tulkita affektiivisen kansalaisuuden näkökulmasta. Hankkeilla tavoitellun yhteisöllisyyden kautta toivotaan tietynlaista kansalaisuutta, jossa hankealueiden asukkaat huomioisivat yhteisön paremmin omassa käytöksessään ja toiminnassaan. Yhteisöllisyyden ajatellaan tuottavan alueille turvallisuuden tunnetta, sosiaalista kontrollia ja luottamusta asukkaiden kesken. Luottamuksen lisäämistä voidaan tulkita myös sosiaalisen pääoman ja asukkaiden välisien heikkojen siteiden lisäämisenä. Yhteisöllisyyden ajatellaan johtavan parempiin väestösuhteisiin ja sujuvampaan kanssakäymiseen paikallisesti. Lisäksi yhteisöllisyyden ajatellaan lisäävän asukkaiden omistajuutta alueisiinsa. Omistajuus puolestaan ilmenisi aktiivisena osallistumista alueen asioiden hoitoon ja haluna pitää alueesta huolta. Yhteisöllisyydellä pyritään siis aktiivisemman ja alueeseensa sitoutuneemman kansalaisuuden edistämiseen. Tutkimustulosten perusteella kaupunkien yhteisöhankkeilla ei nähdä edellytyksiä rakenteellisten ongelmien korjaamiseen, mutta yhteisöllisyydellä nähdään haastatteluaineiston perusteella mahdolliseksi lisätä rakenteellisten ongelmien seurauksista kärsivien asukkaiden psykososiaalista hyvinvointia. Tutkimustulokset tekevät näkyväksi yhteisötyön suunnitteluun vaikuttavia premissejä, mikä mahdollistaa kaupunkien yhteisö- ja osallisuustyötä ohjaavien taustaolettamien kriittisen arvioinnin.