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Tutkielma kartoittaa bayesiläisen lähestymistavan soveltamista joukkoliikenteen lipunmyynnin dynaamiseen hinnoitteluun. Dynaamisessa hinnoittelussa muutetaan tuotteen hintaa taajaan pyrkimyksenä hiljaisempina aikoina houkutella lisää asiakkaita alemmilla hinnoilla ja hyödyntää suuremman kysynnän jaksot nostamalla hintoja. Tutkittavassa tilanteessa pyritään maksimoimaan pitkän matkan linja-autovuoron lipunmyynnistä syntyvä liikevaihto. Oletetaan lippujen myynnin odotusarvon määräytyvän jonkin kysyntäfunktion perusteella, ja että kysyntä riippuu myyntihinnasta sekä muista muuttujista. Hinnoittelija valitsee kullekin myyntijaksolle hinnan, joka tuottaa jonkin myyntitulon, ja tavoite on siis tietylle linja-autolähdölle maksimoida sen lipunmyynnin kokonaisliikevaihdon odotusarvo yli myyntijaksojen etsimällä parhaat hinnat. Hinnoittelussa esitetään noudatettavaksi seuraavaa lähestymistapaa. Oletetaan kysynnän noudattavan log-lineaarista mallia. Käytetään sen parametreille priorijakaumaa, jonka hyperparametreille lasketaan suurimman uskottavuuden estimaatit aiemmin kerätyn datan perusteella. Kussakin yksittäisessä hinnoittelujaksossa kysyntäfunktion parametreille muodostetaan myyntikauden edellisten hinnoittelujaksojen toteutuneiden myyntien perusteella uskottavuus. Sitten parametrien uskottavuuden ja priorijakauman perusteella muodostetaan parametrien posteriorijakauma, jota arvioidaan Markovin ketju -- Monte Carlo -menetelmin. Viimein posteriorijakauman antamaa tietoa kysynnästä käytetään myyntijakson hinnan optimoimiseen varmuutta vastaavan hinnoittelustrategian mukaisesti, eli olettaen parametriestimaatit virheettömiksi.

In the field of scientific research, computer simulation, Internet applications, e-commerce and many other applications, the amount of data is growing at an extremely fast pace. In order to analyze and utilize these large data resources, it is necessary to rely on effective data analysis techniques. The relational database (RDBMS) model has always been a dominant database model in database management. However, the traditional relational data management technology encountered great obstacles in the scalability, as it has difficulties with the big data analysis. Today, the cloud databases and NoSQL databases are attracting widespread attentions and become optional choices besides the relational database. This thesis mainly focuses on benchmarking studies of two multi-model NoSQL databases, ArangoDB and OrientDB and discusses the use of NoSQL for the big data analysis.

Isomorphic web applications combine the best parts of static Hypertext Markup Language (HTML) pages and single-page applications. An isomorphic web application shares code between the server and the client. However, there is not much existing research on isomorphic web applications. Improving the performance, user experience and development experience of web applications are popular research topics in computer science. This thesis studies the benefits and challenges of isomorphism in single-page applications. To study the benefits and challenges of isomorphism in single-page applications, a gray literature review and a case study were conducted. The articles used in the gray literature review were searched from four different websites. To make sure the gray literature could be used in this study, a quality assessment process was conducted. The case study was conducted as a developer survey, where developers familiar with isomorphic web applications were interviewed. The results of both studies are then compared and the key findings are compared together. The results of this study show that isomorphism in single-page applications brings benefits to both the developers and the end-users. Isomorphism in single-page applications is challenging to implement and has some downsides, but they mostly affect developers. The performance and search engine optimization of the application are improved. Implementing isomorphism makes it possible to share code between the server and the client, but it increases the complexity of the application. Framework and library compatibility are issues that must be addressed by the developers. The findings of this thesis give motivation for developers to implement isomorphism when starting a new project or transforming existing single-page applications to use isomorphism.

Dehydroabietic acid is a natural diterpene readily available from disproportionated rosin. This natural product has attracted the interest of both the synthetic, medical and pharmacological communities due to the wide variety of important biological activities it exhibits. In search for potent pharmaceutical agents, numerous derivatives of dehydroabietic acid have been designed and synthesized accordingly. One key reaction in such syntheses is the benzylic oxidation of positions 7 and 15 in the dehydroabietane core. The oxidized derivatives act as key intermediates in the synthesis of both natural and unnatural dehydroabietanes and related compounds. In the literature part of this thesis, known methods for the benzylic C–H oxidation of dehydroabietanes are presented. In the majority of these methods noxious Cr(VI) compounds are required which produce large amounts of toxic waste. The growing concern on the environmental impact of chemicals has led to an increasing interest towards developing environmentally friendlier oxidation procedures, using cheap and readily available oxidants. Recently, much research has focused on the development of transition metal free approaches for benzylic C–H oxidation. The topic is also discussed in this thesis. In the experimental part transition metal free methods for the benzylic oxidation of dehydroabietic acid derivatives are investigated. An environmentally friendly procedure using sodium chlorite in the presence of aqueous tert-butyl hydroperoxide is described. This procedure resulted in the formation of several variously oxygenated dehydroabietic derivatives which were characterized by IR, NMR and HRMS spectrometry. A manuscript is being prepared based on some of the results presented in this thesis.

Over the last 30 years, the geology and paleohydrology has been examined at Olkiluoto as to predict how they may change in the future and affect the final placement of nuclear waste. Some knowledge about the hydrology can be seen directly from present groundwater and the fracture calcite reflect older environments from where they were precipitated. Calcite is the most used fracture mineral within paleohydrogeochemical studies since it easily precipitates during different conditions, including colder climate. The calcite at Olkiluoto has also earlier been examined and dating and grouping of the calcite has been carried out. The aim of the study was to further analyze the trace element composition in fracture calcite samples from earlier studies, in order to understand the influences of groundwater in calcite. The REE concentrations and their anomalies were of special interest. 31 calcite samples from a depth of about 12–660 m under the surface, from 20 different drill cores were analyzed. The calcite had been precipitated at pegmatitc granite, mica gneiss, migmatitic mica gneiss, quartz gneiss and veined gneiss. The calcite was analyzed with ICP-AES (Agilent MP4100), ICP-MS (Agilent 7500ce/cx) and LA-ICP-MS (Coherent GeoLasPro MV and Agilent 7900s). The ICP-AES method was found unsuited for trace element analyses of calcite. The trace element concentrations showed large variations. The later calcite had larger concentrations and more variation towards the surface than deeper in the ground. REE concentrations decreased over depth which can reflect the Ca in the groundwater that increases with depth. LREE showed higher concentrations than HREE since soluble HREE tend to stay in the groundwater during calcite precipitation as LREE migrates to the calcite. Larger LREE concentrations may have occurred from hydrothermal conditions. Usually the calcite had negative Eu anomaly but also positive occurred. Reducing conditions create negative Eu anomalies when Eu3+ takes divalent form. The positive Eu anomalies may also have occurred during hydrothermal conditions or may reflect plagioclase in the bedrock. No direct influence between bedrock and calcite trace element composition could however be determined. The calcite usually lacked Ce anomaly except for a couple near the surface which may be caused by oxidizing conditions where Ce3+ changes to soluble Ce4+. The negative Ce anomalies in calcite from meteoric water, may have inherited the anomaly from earlier seawater. A few La anomalies were observed. Negative La anomaly may occur if La has been taken by other minerals. Usually the calcite lacked Y anomaly except for the oldest calcite that had positive Y anomaly. Acidic conditions tend to cause Fe oxyhydroxation and reduce REE in comparison to Y which may have produced positive Y anomalies. Reducing conditions may also have caused the higher Mn and Fe concentrations in calcite while oxidizing conditions may have created the higher U concentrations. Bacterial activity and clay accumulations during calcite precipitation may have affected Mn concentrations and sulfide precipitation may have affected Fe. The U concentrations in groundwater tend to decrease with depth and at high salinity which may have affected the U concentration in calcite. Variations in Mg concentrations may have been caused by Mg ion exchange. High Sr concentrations may reflect hydrothermal conditions while low Sr concentrations may reflect low temperatures or precipitation of other minerals.

Ecometric analysis allows one to identify relationships between traits measured in organisms and conditions measured in the organisms' local environment. In developing an ecometric model, one selects phenotypic features of organisms which potentially are adaptations to local environment, aggregates measures of these features by organismal community, and quantitatively relates these to measures of the environment via statistical modeling, such that organismal traits may be used to predict environmental conditions. Once established, these models may be applied to fossil assemblages, to reconstruct local paleoenvironment using traits preserved in the fossil record. In this ecometrics case study, we addressed a number of related research questions: what bioclimatic and threshold measures of temperature and/or precipitation are most closely correlated with large, herbivorous mammal communities' mean hypsodonty (HYP) in sub-Saharan Africa? Do these correlations differ at differing spatial scales; specifically, do mammal communities in Kenya's national parks and reserves together relate differently to local environment than do communities in the Afrotropics ecoregions? Finally, what do results obtained by ecometric analysis suggest concerning organismal evolution and dispersal in sub-Saharan Africa? In pursuing answers to these questions, we also pursued the case study's primary objective: we developed and implemented a set of best practices for ecometric analysis, based on an assessment of the sensitivity of ecometric models to model-building decisions, and to uncertainty in source datasets. Ecometric analyses frequently make use of raster datasets - continuous coverages of temperature, precipitation, productivity, and other environmental properties - in characterizing local environment at study localities. Thus we primarily asked: are ecometric results dependent on raster resolution or resampling algorithm? Results of these sensitivity analyses are encouraging. Using the recommended mean resampling algorithm, change in linear regression equations with raster resolution is predictable, and not significant until very low resolutions, in which the average raster cell area is an order of magnitude or more greater than the average locality area. Moreover, using the recommended area-weighted averaging in calculating environmental observations at localities ameliorates this predicable trend in derived regressions. In working 'behind the scenes' addressing these methodological questions, we enable more informed interpretation of ecometric results, and allow future researchers to proceed to the real business of ecometrics with a vetted set of analytical methods. Moreover, in promoting better understanding of ecometric results, we promote better understanding of the complex relationships between organisms and environment, essential to understanding the biosphere's past and present, and to protecting it in the future.

This paper studies discourses about suburbs that occur in newspaper writings about 1960s and 1970s infill development. The study aims to find out how writings about infill development are structured in the local newspaper Helsingin Sanomat between 2000 and 2016. The objective is to discover how a high-rise suburb appears as a site for infill development, and what kinds of discourses appear in newspaper writings about infill development. The paper uses discourse analysis to examine how high-rise suburbs built in 1960-1970 are discussed in Helsingin Sanomat between 2000 and 2016, using writings about infill development in Helsingin Sanomat in that period as research material. Due to the choice of newspaper, the addressed suburbs are found in the Helsinki metropolitan area. In recent years, Finnish urbanization has led to regional economic marginalization, which in the Helsinki metropolitan area is concentrated in the high-rise suburbs of the 1960s and 1970s. In addition to economic marginalization, these suburbs are seen to suffer from decreasing and aging population, and a need for renovations. The stated aims of infill development include urban unification and social diversification of the suburbs in order to prevent the cycle of economic marginalization. Combined with deterioration of apartments built in the 1960s and 1970s, structural and social problems in high-rise suburbs have led to a societally challenging situation. The writings contained four discourses about suburbs: potential of the suburbs, defense of the suburbs, the suburb as problematic, and the suburb as a conflict-prone site for infill development. The most powerful discourse was about potential. The defense discourse emphasized the uniqueness and meaningfulness of the suburb as the environment and home of its inhabitants. The conflict discourse refers to writings where the suburb is seen as an infill development site that causes conflict. While most of the newspaper writings mention the age and deterioration of the period’s suburbs, the problem discourse did not dominate the research material. Based on the research, the ways of talking about the suburb depend on the speaker, the speaker’s motives, and the subject. The discourses allowed a crucial observation that the suburb is an arena for wielding power where a contradictory and naïve attitude towards developing suburban social life is a major problem slowing down the prevention of economic marginalization. Because the suburbs of the Helsinki metropolitan area are very different, the research doesn’t reveal what suburbs are really like. Instead, the research shows how the suburbs of the metropolitan area appear in the context of writings about infill development, and reveals the persons featured in writings about infill development as well as the suburbs that are interesting to the media. The study also examines how different parties react to infill development, and seeks to shed light on the motives behind the remarks of different parties.

Bézout's theorem, at least the original version, concerns the number of intersection points of two curves in projective plane. The main purpose of this thesis, apart from proving the classical version of Bézout's theorem, is to give multiple generalizations for it. The first proper chapter, Chapter 2, is devoted to the proof of classical Bézout's theorem. In the first two sections of the chapter we define projective and affine plane curves, and show some of their basic properties. In the third section we define the resultant of two polynomials, and use the newly acquired tool to prove the upper bound version of Bézout's theorem. The fourth section discusses the multiplicity of a point of intersection. This multiplicity, dependent of algebraic data associated to the intersection, is needed for stating the equality version of the classical Bézout's theorem. In the fifth section we prove this using properties of the intersection multiplicity proved in the fourth section. The third chapter extends the classical Bézout's theorem beyond its original scope. In Section 3.1 we define a crucial tool, Hilbert polynomial, which allows us to keep track of algebraic information associated to the projective scheme cut out by a homogeneous ideal. This polynomial is not an invariant of the scheme itself; rather it should be thought as containing information concerning both the intrinsic structure of the subscheme, and about how the subscheme is located in the ambient projective space. The second section of the third chapter quickly summarizes the parts of modern algebraic geometry that are of most use later. Section 3.3 gives the first proper generalization of Bézout's theorem. This generalization is more a quantitative than a qualitative one, as it deals with intersections of projective hyperplanes. The fourth chapter gives a generalization of the upper bound version of the Bézout's theorem to a very general case. We define the geometric multiplicity of a closed subscheme of a projective space, and show that it behaves well under intersections. The geometric multiplicity gives an upper bound for the number of components, hence the generalization of inequality version of Bézout. In the final section, 3.5, we define Serre's multiplicity of a component of intersection, and show that the multiplicities given by this formula satisfy the equality version of Bézout's theorem in proper intersections of equidimensional subchemes.

Tietovarannoissa esiintyy monesti useita tietueita, jotka kuvaavat samaa objektia. Tässä tutkielmassa on vertailtu näiden tietueiden löytämiseen käytettäviä menetelmiä. Kokeet on suoritettu aineistolla, jossa on 6,4 miljoonaa bibliografista tietuetta. Menetelmien vertailussa käytettiin aineistossa olevien teosten nimekkeitä. Eri menetelmien kahta keskeistä piirrettä on mitattu: löydettyjen duplikaattien lukumäärää ja niiden suhdetta muodostettujen kandidaattien lukumäärään. Kahden menetelmän yhdistelmä osoittautui parhaaksi aineiston deduplikointiin. Järjestetyllä naapurustolla löytyi eniten varsinaisia duplikaatteja, mutta myös eniten irrelevantteja kandidaatteja. Suffiksitauluryhmittelyn avulla löytyi lisäksi joukko duplikaatteja joita muilla menetelmillä ei löytynyt. Yhdessä nämä kaksi menetelmää löysivät lähes kaikki duplikaatit mitä kaikki tutkielmassa verratut menetelmät löysivät. Levenshtein-etäisyyteen perustuvat virhesietoiset menetelmät osoittautuivat tehottomiksi nimekkeiden deduplikoinnissa.