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Pollen samples from Lake Lavijärvi (sediment core LAV16-05) located in western Karelian Russia were examined. 21 pollen and spore types were identified in the process to reconstruct the past ~3000 years vegetation cover and consequently understand major climate pattern of the area. The pollen diagram was divided into 4 zones determined by the main vegetation changes: Zone A (2700 to 1400 cal BP or 750 BC to 550 AD) representing a consistent arboreal forest; Zone B (1400 to 650 cal BP or 550 to 1300 AD) demonstrating a transition from forest to forest-steppe vegetation; Zone C (650 to 10 cal BP or 1300 to 1940 AD) illustrating fluctuations of vegetation patterns; and finally, Zone D (10 to -66 BP or 1940 to 2016 AD) showing the recent post-war relaxation of land-use. Pinus, Picea, Betula, Alnus, Chenopodiaceae and Poaceae are among the major pollen types. Throughout the core changes in vegetation patterns and slash and burn cultivation are well represented. The Medieval Warm Period and the Little Ice Age are also moderately present in the pollen frequency and variety. The anthropogenic effects of farming are displayed by large abundances of Poaceae and Cerealia pollen especially in Zone C, eutrophication of the lake and the absence of Picea pollen due to fires. Today, the lake’s surrounding is mainly pasture with arable farming taking place moderately. The climate of Lavijärvi appeared to have had long winters with excessive snow cover especially in the early stages (2600 to 1000 cal BP or 650 BC to 950 AD) and a moderately dry temperature due to Chenopodiaceae growth though maintaining enough soil moisture for cultivated plants. Other geochemical indicators such as TIC, TN and C/N of core LAV 16-05 were measured. The geochemical findings represent a silt loam sediment profile for the core along with an organic rather than inorganic carbon available together with steady yet low levels of TN and TS. Lake Lavijärvi is a good example of shifting from dense arboreal forest to steppe-like vegetation and finally pasture throughout a window of 3000 years and can reveal useful information on the land-use history of the area.

eBusiness collaboration and an eBusiness process are introduced as a context of a long running eBusiness transaction. The nature of the eBusiness collaboration sets requirements for the long running transactions. The ACID properties of the classical database transaction must be relaxed for the eBusiness transaction. Many techniques have been developed to take care of the execution of the long running business transactions such as the classical Saga and a business transaction model (BTM) of the business transaction framework. Those classic techniques cannot adequately take into account the recovery needs of the long running eBusiness transactions and they need to be further improved and developed. The expectations for a new service composition and recovery model are defined and described. The DeltaGrid service composition and recovery model (DGM) and the Constraint rules-based recovery mechanism (CM) are introduced as examples of the new model. The classic models and the new models are compared to each other and it is analysed how the models answer to the expectations. Neither new model uses the unaccustomed classification of atomicity even if the BTM includes the unaccustomed classifying of atomicity. A recovery model of the new models has improved the ability to take into account the data and control dependencies in the backward recovery. The new models present two different kinds of strategies to recover a failed service. The strategy of the CM increases the flexibility and the efficiency compared to the Saga or the BTF. The DGM defines characteristics that the CM does not have: a Delta-Enabled rollback, mechanisms for a pre-commit recoverability and for a post-commit recoverability and extends the concepts of a shallow compensation and a deep compensation. The use of them guarantees that an eBusiness process recovers always in a consistent state which is something the Saga, the BTM and the CM could not proof. The DGM offers also the algorithms of the important mechanisms. ACM Computing Classification System (CCS): C.2.4 [Distributed Systems]: Distributed applications

This thesis analyses the alterations of vertically integrated atmospheric meridional energy transport due to polar amplification on an aqua planet. We analyse the energy transport of sensible heat, latent energy, potential energy and kinetic energy. We also cover the energy flux of the mean meridional circulation, transient eddies and stationary eddies. In addition, we also address the response of the zonal mean air temperature, zonal mean zonal wind, zonal mean meridional wind, zonal mean stream function and zonal mean specific humidity. Numerical model experiments were carried out with OpenIFS in its aqua planet configuration. A control (CTRL) and a polar amplification (PA) simulation was set up forced by different SST (sea surface temperature) patterns. We detected tropospheric warming and atmospheric specific humidity increase 15-90° N/S and reduction of the meridional temperature gradient throughout the troposphere. We also found reduced strength of the subtropical jet stream and slowdown of the mean meridional circulation. Important changes were identified in the Hadley cell: the rising branch shifted poleward and caused reduced lifting in equatorial areas. Regarding the total atmospheric vertically integrated meridional energy transport, we found reduction in case of the mean meridional circulation and transient eddies in all latitudes. The largest reduction was shown by the Hadley cell transport (-15%) and by midlatitude transient eddy flux (-23%). Unlike most studies, we did not observe that meridional latent energy transport increases by polar amplification. Therefore, it is stated that the increased moisture content of the atmosphere does not imply increased meridional latent energy transport, and hence there is no compensation for the decrease of meridional dry static energy transport. Lastly, we did not detect stationary eddies in our simulations which is caused by the simplified surface boundary (i.e. the water-covered Earth surface). The main finding of this thesis is that polar amplification causes decreasing poleward energy transport on an aqua planet.

Hiukkasfysiikan standardimalli kuvaa alkeishiukkasia ja niiden välisiä vuorovaikutuksia. Higgsin bosonin löydön (2012) jälkeen kaikki standardimallin ennustamat hiukkaset on havaittu. Standardimalli on hyvin tarkka teoria, mutta kaikkia havaittuja asioita ei voida kuitenkaan selittää standardimallin puitteissa. Supersymmetria on yksi houkutteleva tapa laajentaa standardimallia. Matalan energian supersymmetriaa ei kuitenkaan ole havaittu. Supersymmetria vaatii toimiakseen niin sanotun kahden Higgsin dubletin mallin. Tavallisessa standardimallissa on yksi Higgsin dublettikenttä. Higgsin dubletissa on kaksi kompleksista kenttää eli yhteensä neljä vapausastetta, joten voisi olettaa, että siitä syntyy neljä hiukkasta. Kolme vapausasteista kuitenkin sitoutuu välibosoneihin W+, W− ja Z, jolloin jäljelle jää yksi Higgsin bosoni. Kahden Higgsin dubletin malleissa dublettikenttiä on kaksi. Koska se lisää teoriaan yhden neljän vapausasteen dubletin, Higgsin hiukkasia on siinä kaiken kaikkiaan viisi: kolme sähköisesti neutraalia (h, H ja A) sekä kaksi sähköisesti varattua (H+ ja H−). Tässä työssä keskitytään varattujen Higgsin hiukkasten etsintään malliriippumattomasti. Tutkimuksessa käytetään LHC-kiihdyttimen (Large Hadron Collider, suuri hadronitörmäytin) CMS-ilmaisimen (Compact Muon Solenoid, kompakti myonisolenoidi) keräämää dataa. Sähkövarauksellisten Higgsin bosonien etsintä keskittyy lopputiloihin, joissa varattu Higgsin bosoni hajoaa hadroniseksi tau-leptoniksi (eli tau-leptoniksi, joka puolestaan hajoaa hadroneiksi) sekä taun neutriinoksi. Niin sanottu liipaisu on tapa suodattaa dataa tallennusvaiheessa, sillä dataa tulee törmäyksistä niin paljon, ettei kaiken tallentaminen ole mahdollista. Eri liipaisimet hyväksyvät törmäystapauksia eri kriteerien perusteella. Liipaisusta aiheutuu merkittäviä systemaattisia epävarmuuksia. Tässä työssä liipaisun epävarmuuksia pyritään pienentämään käyttämällä sellaisia liipaisimia, joiden epävarmuudet ovat pienempiä. Tätä varten analyysi on jaettava riippumattomiin osiin, joiden epävarmuudet käsitellään erikseen. Lopuksi osat yhdistetään tilastollisesti toisiinsa, jolloin kokonaisepävarmuuden oletetaan pienenevän. Tässä työssä tutkitaan, pieneneekö tämä epävarmuus ja kuinka paljon. Näitä menetelmiä käyttäen kykenimme löytämään pieniä parannuksia analyysin tarkkuuteen raskaiden varattujen Higgsin bosonien kohdalla. Lisäksi odotettu raja, jota suurempi varatun Higgsin hiukkasen tuotto tässä lopputilassa olisi havaittavissa, paranee yllättävästi. Tätä rajan paranemista tutkitaan liipaisua emuloimalla. Työ on tarkoitus sisällyttää koko Run2:n datasta julkaistaviin tuloksiin.

The change from pre-descriptive 'waterfall' software process into iterative and incremental models has created a need for redefinition of software requirements engineering. Agile methodologies have emerged to support the paradigm shift by treating the symptoms: emphasizing change management and customer collaboration to embrace volatility of requirements and priorities whilst in development. However, it has been recognized that fast-paced agile development does not provide sufficient support for initial or long-term planning of the software product. Research and practitioner literature have started to address the need with the concept of a high-level definition of the software project's outcome: the software Product Vision. In this thesis, uncertainty in new product development is studied from the perspective of Innovation Management. As a vehicle for reducing uncertainty in software projects, the concept of an software Product Vision (reason for the project's existence) is chosen to be examined from the viewpoints of New Product Development and Software Engineering literature. The work describes sources of uncertainty in software projects and explains the effects of a mutually understood software Product Vision on software project performance and end-product acceptance. Key parameters for an interdisciplinary and unified software Product Vision are identified by studying four existing and one emergent Product Vision models. Finally, a new Product Vision framework (InnCa) is created based on semantic analysis. The framework's applicability on software projects in evaluated in three participatory action research -case studies. As a result, it is concluded that common parameters of a interdisciplinary 'Product Vision' can be identified. The framework created can be used to ideate, rapidly capture, iterate and analyze vague software ideas. It is applicable for sharing knowledge about the project's high-level goals amongst the project's stakeholders. However, it is not argued in this thesis that the framework could be used in all kinds of projects and circumstances. While uncertainty in software projects is a chaotic and complex phenomenon, no 'silver bullet' can address all situations.The topic of software Product Vision may prove grounds for further research, possibly leading to practical tools for assessing and quantifying uncertainty about goals during a software project's trajectory.

The so-called declarative approach has proven to be a viable paradigm for solving various real-world NP-hard optimization problems in practice. In the declarative approach, the problem at hand is encoded using a mathematical constraint language, and an algorithm for the specific language is employed to obtain optimal solutions to an instance of the problem. One of the most viable declarative optimization paradigms of the last years is maximum satisfiability (MaxSAT) with propositional logic as the constraint language. So-called core-guided MaxSAT algorithms are arguably one of the most effective MaxSAT-solving paradigms in practice today. Core-guided algorithms iteratively detect and rule out (relax) sources of inconsistencies (so-called unsatisfiable cores) in the instance being solved. Especially effective are recent algorithmic variants of the core-guided approach which employ so-called soft cardinality constraints for ruling out inconsistencies. In this thesis, we present a structure-sharing technique for the cardinality-based core relaxation steps performed by core-guided MaxSAT solvers. The technique aims at reducing the inherent growth in the size of the propositional formula resulting from the core relaxation steps. Additionally, it enables more efficient reasoning over the relationships between different cores. We empirically evaluate the proposed technique on two different core-guided algorithms and provide open-source implementations of our solvers employing the technique. Our results show that the proposed structure-sharing can improve the performance of the algorithms both in theory and in practice.

Deforestation is an ongoing issue worldwide, and the loss of forests, coupled with climate change, is causing significant changes in global biodiversity and ecosystem functioning. Currently, forests cover approximately 13% of the land area in the United Kingdom, making it one of the least forested countries in Europe. Reforestation efforts aim to increase forest area, ensuring the provision of ecosystem services, biodiversity, carbon storage, and species conservation. The goal in United Kingdom is to increase forest cover from 13% to 17% nationwide by 2050. However, research focusing on the impacts of climate change largely relies on large-scale climates over areas greater than 1 km². Broad-scale climates also called macroclimates affect large areas on a long-term and are spatially very broad scale. Many species, however, experience significantly different temperatures and weather conditions from macroclimates. These microrefugias created by microclimates can provide habitats for species requiring cooler conditions in changing climates. Microclimates have a lot of impact for forest ecology, as they enhance carbon sequestration, microbial activity, and decomposition processes in forests. Many different factors influence the formation of microclimates, such as solar radiation, air temperature, precipitation, soil temperature, humidity, and wind. Vegetation affects radiation and wind near the ground, creating the characteristic microclimate of each area. Buffering refers to the ability of forests to absorb or resist changes in temperature, thereby maintaining more stable temperature conditions compared to temperatures outside the forest. This study aims to find answers on the questions 1. How well can forests buffer macroclimate temperatures and create microclimates? 2.What kind of forest structures create microclimates that differ from the macroclimate? 3.Which types of forests planted in Scotland best support the creation of microrefugia? For this study, microclimate measurements and remote sensing data (TLS) were collected from 21 forest sites in England and Scotland. Macroclimate temperatures were determined using ERA5-Land data and nearby weather stations temperature data. By using linear models and statistical analyses, slope values were made for each forest plot to represent buffering. The results indicate what types of forests enhance temperature buffering and create microclimate conditions. The results indicate that broadleaf and coniferous forests effectively buffer temperatures during the leaf-on period, while their effectiveness diminishes during the leaf-off period. Broadleaf forests showed buffering during the leaf-on period but showed reduced buffering during the leaf-off period. Coniferous forests maintained better buffering during the leaf-on period and low buffering during the leaf-off period. Monoculture forests provided consistent buffering, while older and multi-age forests performed best in both periods, demonstrating the importance of structural complexity and diversity. Certain species, such as spruce, Scots pine, and oak, showed strong buffering capabilities year-round. The linear mixed-effects model confirmed that forest structural traits such as, Foliage Height Diversity and Relative Height and other factors such as hillslope, elevation, and tree type significantly influence temperature buffering. Maintaining diverse and structurally complex forests with a mix of species like spruce, Scots pine, and oak is essential for optimizing temperature buffering and creating stable microclimates and microrefugia. These forests can better withstand temperature fluctuations and provide habitats for species affected by climate change. The study highlights the importance of long-term forest growth and diverse understories in enhancing forest resilience and ecological stability. Further research is needed to understand the broader implications of forest management practices on biodiversity and ecosystem functioning. Further research is also needed in the planning of reforestation in Scotland to understand where reforestation can be most effectively implemented.

There’s a specific but sometimes quite a significant problem in time series modeling caused by changing means. First, the foundation behind the model addressing this problem is introduced in the form of the basic theory of Markov chains and problems related to hidden Markov chains. This approach builds on the ARMA (Autoregressive Moving average) model but is utilizing estimation methods from the areas not specifically dedicated to the time series analysis. The hybrid approach comprising Markov chains, EM (expectation-maximization) algorithm, and linear modeling may be well justified when the conventional methods do not seem to produce desired results and the modeler has competencies and means to attempt more sophisticated approaches. The literature review provides an insight into an earlier kind of models that have led to the development of the model investigated in this work. Finally, in the empirical part the model’s power is assessed against the conventional ARMA model. The modeling is performed on the simulated series in order to assess the functionality of the EM algorithm, to have a precise knowledge about real state variables, and to get an optimal comparison between a linear and non-linear models. The models are compared using multiple diagnostic procedures such as AIC (Akaike criterion), autocorrelation and partial autocorrelation functions, residuals variance, and other descriptive statistical measures.

Opinnäytetyö esittelee moderneissa peleissä usein käytettyjä reitinetsintämenetelmiä sekä etsintäavaruuksia, joissa menetelmät toimivat. Se perehdyttää reitinetsinnän periaatteisiin peruasioista lähtien ja sopii siten esimerkiksi johdannoksi aiheeseen. Näkökulmana on käytännönläheinen ja siinä pyritään ottamaan huomioon pelilaitteiden rajoitukset, etsintämenetelmien toteutuksen hankaluus ja toisaalta pelien sääntöjen tuomat vaatimukset. CCS-luokitus: - Computing methodologies ~ Motion path planning - Applied computing ~ Computer games

Tämän tutkielman päämäärä on osoittaa rekursiivisten funktioiden ja lambda-määriteltävien funktioiden yhtenevyys. Molemmat funktiojoukot ovat laskettavuuden teorian syntyyn vaikuttaneita laskennan malleja, joilla kuvataan automatisoitavissa olevia prosesseja. Kurt Gödel tarvitsi rekursiivisia funktioita predikaattilogiikan todistuvuuden mekanisointiin. Lambda-määriteltävyys taas pohjautuu Alonzo Churchin ideoimaan lambdalaskentaan (engl. lambda-calculus). Se koostuu funktioita esittävistä kaavoista, ja niille määritellyistä muunnossännöistä. Lambdalaskenta on toisinaan suomennettu myös lambdakalkyyliksi. Lambda-määriteltävät funktiot on rekursiivisten funktioiden ohella osoitettu yhteneviksi useiden muidenkin laskentaformalismien kanssa. Tämän johdosta on päädytty otaksumaan, että rekursiiviset operaatiot ovat ne, joita on ylipäänsä mahdollista realisoida jollain algoritmilla tai automaatiolla. Lambdalaskennan synnyinvuosien jälkeen hiljalleen kehittyi laskettavuuden teoria, jossa tutkitaan mitä tällaisilla mekaanisilla järjestelmillä, kuten tietokoneella, voi edes periaatteessa ratkoa. Luvussa 2 esitellään rekursiivisten funktioiden perhe sekä rekursiivisesti ratkeavat relaatiot. Aikaisempi tietämys matemaattisesta logiikasta ja rekursiivisista funktioista on hyödyksi, sillä kaikkien määritelmien semanttista oikeellisuutta ei käsitellä. Luvussa 3 esitellään lambdalaskennan lausekkeet ja muunnossäännöt sekä todistetaan Churchin-Rosserin lause, joka kuittaa lambda-laskennan toimivaksi laskentajärjestelmäksi. Lisäksi todistetaan lambdatermien kiintopistelause, jota vastaava tulos rekursiivisille funktioille on huomattavasti mutkikkaamman todistuksen takana. Aikaisempaa tietämystä lambdalaskennasta ei edellytetä. Luvussa 4 esitellään lambda-määriteltävien funktioiden joukko, joka viimeisessä luvussa osoitetaan samaksi rekursiivisten funktioiden joukon kanssa. Usein laskettavuuden teoriassa sallitaan osittaiset funktiot, joiden arvoa ei kaikissa pisteissä välttämättä ole määritelty. Tässä tutkielmassa käsitellään kuitenkin vain totaaleja funktioita.