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Tämän Pro gradu- tutkielma aiheena on valokuvien tarkentamiseen käytetyt algoritmit. Algoritmien tavoitteena on poistaa valokuvista esimerkiksi liikkeestä tai huonosta tarkennuksesta johtuvia epätarkkuuksia ja kohinaa. Työssä esiteltävissä algoritmeissä ongelmaa käsitellään tilastollisena inversio-ongelmana, jonka parametrien estimointiin käytetään erilaisia numeerisia menetelmiä. Tutkielman rakenne koostuu kolmesta osiosta; yleisestä teoriaosuudesta, työssä käytettävien algoritmien esittelystä sekä algoritmien soveltamisesta data aineistoihin ja tulosten vertailusta. Teoriaosuudessa käydään lyhyesti läpi inversio-ongelmien yleistä teoriaa, keskittyen erityisesti valokuvien tarkentamisen kannalta olennaiseen diskreettiin lineaariseen tapaukseen ja tämän tilastolliseen muotoiluun. Algoritmien puolestaan voidaan ajatella koostuvan kahdesta osasta: (i) tilastollisen mallin määrittämisestä ja (ii) mallin parametrien numeerisesta optimoinnista. Tutkielmassa esitellään kaksi klassista analyyttistä menetelmää nimiltään Richardson-Lucy ja ROF -algoritmit sekä syväoppimista ratkaisussa hyödyntävä iRestNet. Lopuksi algoritmeja sovelletaan kahdelle eri aineistoille: ohjelmallisesti generoidulle datalle ja vuonna 2021 järjestetyn Helsinki Deblur Challenge -haastekilpailun kuva-aineistolle. Tarkoituksena on selvittää algoritmien toteutuksessa tehtävien valintojen vaikutusta lopputuloksiin ja vertailla esiteltyjen algoritmien antamia tuloksia keskenään.

The concept of terrorism has been used widely in discussion about those actors who threaten the state. In this study I try to clarify how terrorism has been located in databases from the United States and compare those results to the Uppsala university's databases considering battle related deaths and one-sided violence. I try to find out which kind of differences there are among databases considering the number of deaths, the type of the targets and the actors who perform the strikes. The theoretical base of this study lies in the theory of critical geopolitics. Critical geopolitics moves the focus from the existing areas to that how areas are produced. The focus is on that what kind of processes there are influencing when areas and our perspective about them becomes to exist to us. Often there are purposeful intentions to enforce certain images about areas in order to achieve political goals. During the years of the war on terror the United States has changed its foreign politics more to the direction where it considers that it has the right to defend itself from threats even when it means using force outside the US borders without international approval. The threat has been often described as terrorism in the media and in political speeches. In this study I use databases from three different sources. The department of homeland security and the national counterterrorism center are created as results of the war on terror to help the government to deal with the threat. The university of Uppsala has produced its own database for decades about different factors considering conflicts. To the original American databases the material has been accepted with more subjective criteria than to the original Uppsala databases. From the information of these databases I produce several cartographic presentations which have an essential meaning in the production of the results. The most important locations of the terrorism are in the Middle East and in the South Asia. In these areas there are also great numbers of battle related deaths. In the Sub-Saharan Africa one-sided violence is often even more common reason of death than battles. Most of the most important actors of the countries are same ones in the different databases. Al'Queda is the only truly global terrorist organization. In the countries where one-sided violence is most severe the targets are usually civilians and in the countries where the battles are more severe the target is usually the government. Terrorist organizations seem to strike only in few countries in most cases. This indicates that even today most of the organizations have quite local goals. Also only few states are using force outside their own or neighboring country. Especially United states and al'Queda are actors who clearly use force globally. This study suggests that this is a process that enforces the global nature of terrorism and counterterrorism and that this is part of the larger process of globalization. One of the most important conclusions of this study is that terrorism seems to relate more to the battles than to one-sided violence. This is the most important reason for the observation that there is little terrorism in same parts of the world compared to violence. The main example of this is Sub-Saharan Africa. This study suggests that the reasons for this might be the weak role of the States in many countries in the area which appears as one-sided violence done by government and as large number of other groups practicing one-sided violence on the continent.

The Master´s thesis examines the conceived value patterns the city officials use in the context of land-use regulation of small forest fragments. As a theoretical framework, the study utilises Boltanski and Thévenot´s theory on the common worlds with complementary literature, such as Thévenot’s cognitive formats and engagements. In light of extensive scientific research, urban greenspaces have multiple positive impacts to both urban structure and wellbeing of the residents. Small greenspaces, so-called forest fragments with no appointed recreational activities are, nevertheless, often presented as potential sites for infill construction. This appears especially in cities where strong population growth causes pressure for urban development. This Master´s thesis complements existing research in this regard by revealing the diversity of valuation that form the basis to differing interests, perspectives and decisions that direct urban land-use policy in these forest fragments. The empirical phase has been conducted among city officials in the City of Espoo (FI), who represent different operative units and positions. The analysis was conducted through an exploratory and semiquantitative Q methodology. In the study, the respondents (N=27) validated statements (Q=35) related to planning decisions on small forest fragments. The factor extraction was conducted by principal component analysis. The seven analysed factors form consistent value patterns, which may be used when describing and interpreting the justification of urban planning regulation in forest fragments. In each individual value pattern, either valuation of the local landscape, public good or personal advantage is emphasised. From the common worlds, argumentation based on the industrial or the market worlds highlight personal affinity, whereas, for instance, the civic or the domestic world form a basis for argumentation on social values and the common good. Human-centred biophilia is the most explanatory of the value patterns. Based on the valuation, forest fragments are seen as an integral part of the urban structure especially due to their cultural ecosystem services, such as recreational possibilities, effect on residents´ environmental consciousness and stability of the local landscape.

The arctic region is sensitive to climate change impacts. Arctic lakes are typically transparent and shallow. Environmental changes occurring in the catchment reflect to DOC (dissolved organic carbon) and nutrients concentration of arctic lakes. Furthermore, productivity of lakes, organic matter transport and mineralization will change. This thesis examines how the catchment characteristics currently impact the limnology of arctic lakes and assess future changes when temperature and precipitation will increase. Special attention is given to DOC due to its strong impact on the lake ecosystem. Water and sediment samples were collected from 31 lakes from Ivalo to Utsjoki (68°47' and 69°55') at the end of July 2014. pH was measured in situ and the vegetation type of catchment was observed. LOI 550- % (loss-on-ignition) and chlorophyll-a-sediment were measured from surface sediment (0-2 cm). DOC, TP (total phosphorus), TN (total nitrogen), chl-a-water (chlorophyll-a-water), CDOM (colored dissolved organic carbon) components C1-C4,C6, SUVA (specific UV-absorbance), FI-index (fluorescence index) and HI-index (humification index) were measured from water samples from the epilimnion. Catchment variables were analyzed by using GIS (geographical information system) to determine boundaries, area, topography and altitude of catchments. Based on general map raster of National land survey of Finland © wetland- %, forest- %, tundra- % and lake- % were digitized. Vegetation type was determined based on general map raster and field observations. The July mean temperature during 1984–2013 was calculated based on mean temperature raster of Finnish meteorological institute ©. Principal component analysis (PCA) was used to determine catchment variables which most impact the limnology. Based on principal component analysis results the most effective catchment variable is wetland -% which has a strong impact on DOC, nutrients, chlorophyll-a-water, CDOM components C1-C4, C6 and HI-index. Wetlands are important source of DOC and nutrients to the lakes and the impact of wetland- % is stronger than vegetation type hence DOC-gradient follows wetland- %. On the other hand, tree line and dwarf birch catchments without wetlands are seen clearly in results as lakes with low DOC and nutrient concentrations. Climate change affects catchments and is assumed that release of DOC and nutrients from wetlands and forested areas will increase. Longer ice-free period increases the length of the growing season and will likely, together with increased nutrients, result in a higher water column production in arctic lakes. On the other hand, increased DOC in water column will decrease the amount of light and the production will decrease. Thus, we can expect that the area of tundra vegetation will decrease and dwarf birch will spread to tundra. In addition, the density of trees in forested areas will increase and the tree line will shift northward and higher up the fjells. Environmental changes have substantial impact on the lakes and catchments studied in this thesis. DOC, nutrients and production will probably increase in the studied lakes.

The aim of this study is to examine housing preferences among households in the city of Vantaa. Research interest lies in the different household groups and their valuations associated with housing. The purpose is to find out what kind of housing preferences different households have and to examine whether there can be found differences within the city. Housing preferences are examined through revealed and stated preferences. The revealed preferences are determined by analyzing the current housing choices of the households. Preferred choices for future housing as well as valuations associated with housing are analyzed in order to study the stated preferences. The study is quantitative in nature. The residential survey data has been provided by the city of Vantaa. The survey data has been collected at the turn of the year 2018-2019. The most important methods used are descriptive statistics, factor analysis and regression analysis in SPSS statistics. In addition, the City of Vantaa’s open data spatial datasets are used as background material for the spatial examination of both revealed and stated housing preferences with QGIS 3.4 application. The most important findings of this study confirm that there exists a connection between different life stages, and both revealed and stated preferences. The most common revealed preference among the households in Vantaa according to tenure type is owner occupied housing and, according to the type of house, an apartment building. The revealed preference for rental housing is emphasized among the youngest and one-person household respondents. The preference for living in an apartment building is most common among the youngest, older, and one-person household respondents. Majority of the households live in accordance with their preferences according to the analyzed survey data. From the point of view of the stated preferences, the future housing aspirations of households emphasize the popularity of owner-occupied housing: the majority of the respondents want to live in owner-occupied apartment in the future. Hopes for the desired size of the apartment in the future are related to the size and the stage of life of the households. Younger, older, and one-person household respondents are more urban-oriented than other residents in the light of the survey data.

Nanorypään ominaisuuksien ymmärtämisen ja ennustamisen kannalta on keskeistä tuntea tekijät, joiden perusteella rypään tasapainorakenne määräytyy. Nämä tekijät voidaan jakaa energeettisiin, termodynaamisiin ja kineettisiin tekijöihin. Energeettisiin tekijöihin kuuluvat rypään sidosenergia ja elektronirakenne. Termodynaamisia tekijöitä ovat rypään erilaiset entropiatermit. Kineettiset tekijät puolestaan liittyvät rypään muodostumisprosessin kulkuun. Tässä työssä tutkittiin värähtelyentropian vaikutusta vapaiden kuparinanorypäiden tasapainorakenteeseen atomistisilla simulointimenetelmillä 10 - 6525 atomin kokoluokassa 0 K - 600 K lämpötila-alueella. Tarkasteltaviksi valittiin kahdeksan ideaalista rakennetyyppiä: Mackayn ikosaedri, täydellinen oktaedri, katkaistu oktaedri, säännöllinen katkaistu oktaedri, kuboktaedri, säännöllinen dekaedri, Marksin dekaedri ja Inon dekaedri. Näiden lisäksi tarkasteltavina oli kaasukondensaatiosimulaatioilla tuotettuja rypäitä. Tarkasteltaville rypäille laskettiin ominaisvärähtelytaajuuksien tilatiheysfunktiot harmoniseen approksimaatioon perustuen. Tilatiheysfunktioiden perusteella laskettiin kullekin rypäälle Helmholtzin vapaan energian lämpötilariippuvuus, josta edelleen rypään stabiiliutta kuvaava delta-parametri. Tasapainotilassa olevan rypään potentiaalifunktion anharmonisuus huomioitiin kvasiharmonisen approksimaation avulla. Atomien välistä vuorovaikutusta kuvaamaan käytettiin EAM-potentiaalimallia kuparille. Eri rakennetyyppien välistä kilpailuasemaa verrattiin delta-parametrin avulla. Tulosten perusteella Mackayn ikosaedri on edullisin rakenne alle 2000 atomin kokoluokassa, kun lämpötila on 0 K. Atomimäärän kasvaessa katkaistu oktaedri -rakenteet ottavat edullisimman rakenteen paikan. Lämpötilan noustessa ikosaedrirakenne pysyy edullisimpana yhä suurempiin kokoluokkiin, ja 600 K lämpötilassa se on edullisin rakenne lähes 4000 atomin kokoon saakka. Kaasukondensaatiosimulaatioilla tuotettujen rypäiden delta-parametreja verrattiin ideaalisiin rakennetyyppeihin. Anharmonisten korjausten ei havaittu vaikuttavan tuloksiin tarkasteltavalla koko- ja lämpötila-alueella.

Kun vakuutusyhtiön alkupääoma ja vakuutusmaksut korkoineen eivät riitä vahinkojen korvaamiseen, tapahtuu vararikko. Vararikkotodennäköisyyksien laskeminen täsmällisesti on haastavaa, mutta tekemällä oletuksia vakuutuskannasta vararikkotodennäköisyydelle on pystytty johtamaan arvioita. Tämän tutkielman tarkoitus on löytää arvio äärettömän aikajänteen vararikkotodennäköisyydelle siinä tilanteessa, kun paras jakauma vahinkojen suuruuksien arvioimiselle on paksuhäntäinen ja kun vakuutusyhtiön on mahdollista saada varoillensa riskitöntä sijoitustuottoa. Tarkastelu on rajattu niihin paksuhäntäisiin jakaumiin, joiden häntä on säännöllisesti vaihteleva. Tutkielmassa on pyritty esittämään esimerkkejä aiheen selventämiseksi ja lisäksi päätulosta havainnollistetaan simuloimalla vararikkotodennäköisyyttä eräässä esimerkkitapauksessa. Kokonaisvahinkomäärän arvioimisessa käytetään yleisesti Cramér-Lundbergin mallia. Siinä vahinkojen tapahtumishetkiä ja niiden suuruuksia käsitellään erillisinä, toisistaan riippumattomina prosesseina. Vahinkojen suuruuksia voidaan mallintaa erilaisten jakaumien avulla riippuen vakuutuskannan erityispiirteistä. Monissa vakuutuslajeissa suurten vahinkojen tapahtuminen on normaalia todennäköisempää. Tällöin vahinkojen suuruuksia voidaan mallintaa paksuhäntäisten jakaumien avulla, koska niissä ääriarvojen sattumistodennäköisyys on suhteellisen suuri. Osa paksuhäntäisistä jakaumista on säännöllisesti vaihtelevia eli niiden häntäfunktiot käyttäytyvät rajalla samoin. Tässä tutkielmassa paksuhäntäisyyden tarkastelussa käytetään hyväksi säännöllisen vaihtelun käsitettä. Perusesimerkkinä paksuhäntäisestä ja säännöllisesti vaihtelevasta jakaumasta käytetään Pareto-jakaumaa. Tutkielman päälähde on Claudia Klüpperbergin ja Ulrich Stadtmüllerin artikkeli Ruin Probabilities in the Presence of Heavy-Tails and Interest Rates (1998), jossa todistus vararikkotodennäköisyyden arviolle tutkielmassa tehdyin oletuksin on alun perin esitetty.

Growing population in cities increases the share of global greenhouse gas (GHG) emissions coming from urban areas. To understand the energy, water and GHG emission exchanges between urban surface and the atmosphere, modelling is a necessary tool. This is because measurements are not always available from all the different urban environments. In the case of carbon dioxide CO2 exchange, modelling is needed to provide new information on the different anthropogenic and biogenic components over various land uses. In this thesis, the aim was first to compare energy and CO2 fluxes from an urban land surface model called Surface Urban Energy and Water Balance Scheme (SUEWS) against measurements from suburban neighbourhood in Minneapolis, USA. The second aim was to study differences in the fluxes between years in the area. The model is parameterized with surface information about the study area, which is divided into two grids, residential and recreational area. The meterological forcing data are derived from ERA5. In the first part of the study, SUEWS is run in the area from June 2006 to April 2009, and the fluxes of latent QE and sensible QH heat and CO2 are compared against eddy covariance (EC) measurements conducted in the same area in the same time period. The diurnal cycles of CO2 show that the model is able to catch the daytime values well in every season for both study area grids, but night-time positive values are difficult especially for recreational area in autumn and winter. The model also underestimates the emissions in every season in the morning and evening rush hour peaks, which are caused by traffic. Overall, CO2 flux is simulated reasonably well. The model performs very well against QE measurements, but more poorly against QH. The second part of the study extended time period from January 1995 to April 2009 to analyze the long-term variation of fluxes. These were studied independently without the measurement comparisons. Annual cumulative sum of CO2 showed great variation between the years, and the highest value was emissions of 1135 gCm-2year-1 in 2001 and the lowest 600 gCm-2year-1 in 2005 from the residential area. Annual cumulative sums of QE did not show so much variation. The reason behind the differences between these two years was the great variation of photosynthesis. In 2001 air temperature restrained photosynthesis when surface conductance and its environmental factors were further studied. No statistical difference between the years 2001 and 2005 was though found.

Species are distributed to small-scale local communities by an interplay of environmental and spatial factors. As microbial species with efficient passive dispersal capacity and thus mainly under local environmental control, diatom communities nevertheless consistently show a strong spatial structuring as well. Different metacommunity perspectives have been developed to describe the relationship between environmental and spatial factors and their relative role for local communities. This study aims to examine the relative roles of environmental and spatial factors for diatom species composition and community similarity for defining the dominating metacommunity type among coastal rock pool communities. Factors affecting local species richness are also studied. Rock pools are granitic water-filled depressions occurring in high numbers on coastal rocky outcrops. Due to their clearly delineated borders, hierarchical spatial structure and interacting biota, rock pools are well suited for ecological metacommunity studies. In this study, 30 brackish-watered rock pools located on the coast of the northern Baltic Sea were studied over a three-month period from May to July in the summer of 2016. The data consisted of benthic diatom samples, estimated pool spatial coordinates and relative isolation, and water physiochemical characteristics. Environmental and spatial factors most responsible for variation in species richness and community composition were determined with generalized linear models and redundancy analysis, respectively. The relative roles of environmental and spatial factors for community composition were quantified with variation partitioning. Distance decay in community similarity was further determined with Mantel and partial Mantel tests. According to the results of monthly GLMs, diatom species richness was best explained by water conductivity and rock pool spatial location. Specifically, the distance from the sea had a clear role in regulating pool water physiochemistry and species richness. Variation partitioning revealed that diatom community composition was significantly explained by both environmental and spatial variables in each month. The joint effect of these factors was consistently larger than the pure effects of neither variable group. Environmental and spatial variables most in charge of diatom community composition in RDAs were water conductivity and pool distance from the sea, with a lesser impact of water pH, total phosphorus concentration, temperature and pool isolation. According to Mantel tests, community similarity was significantly related to both environmental and spatial distance between the pools. The influence of environmental factors increased during the summer, accounting for the largest share of the variation in community composition and distance decay of community similarity in June and July. In the light of these findings, the significant role of both environmental ans spatial factors and the overall metacommunity organization in the studied rock pools are best explained by mass effect. It seems that while the variable physiochemical conditions maintain strong environmental control over the local diatom communities consisting of mainly highly specialized species, efficient passive dispersal acts as a continuous supply of more generalist species. This pattern, accompanied with significant distance decay of community similarity eventually leads to spatially heterogeneic and diverse communities with weaker yet significant spatial control.

Entanglement entropy is a proposal to quantify quantum entanglement of two disjoint regions in a pure system. It is a relatively new topic and is developing rapidly. The current main motives to study it are its applications to studying quantum gravity, thermalization and phase transitions in condensed matter systems. Mutual information is a related quantity and it can be used to measure the amount of information two disjoint regions share. The purpose of this thesis is to give an introduction to the general results of the field without considering specific systems. The two prominent approaches used are two-dimensional conformal field theory and the holographic entanglement entropy conjecture. The first approach is to calculate entanglement entropy using conformal field theory, the results of which are known to be exact although technically more difficult to derive and only available for 1+1 dimensional systems. Both static and dynamic systems will be discussed. The results are reproduced and generalized to higher dimensions using holography. As a more recent topic, the holographic approach is used to rederive the entanglement entropy of systems with a Fermi surface using AdS/Vaidya metric with Lifshitz scaling and hyperscaling violation. The final chapter of the thesis discusses mutual information in various static and dynamic cases considered in the previous chapters. For the first time, the evolution of mutual information is calculated in AdS/Vaidya metric with Lifshitz scaling and hyperscaling violation in the critical theta=d-1 case.