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The crystal structure of magnetite (Fe3O4) involves Fe2+ ions in sites with octahedral (Oh) symmetry and Fe2+ and Fe3+ ions in sites with tetrahedral (Td) symmetry. Magnetite exhibits several interesting physical phenomena, such as the Verwey transition, in which the roles of the different Fe sites are an active subject of research. In the X-ray standing wave (XSW) technique, incoming and diffracted X-ray beams interfere inside a crystal, creating a standing wave with the periodicity of the diffracting atomic lattice. The phase of the wave, i.e. whether the nodes are located on the lattice planes or between them, can be adjusted by finely tuning the diffraction angle. Changing the phase in this way makes it possible to selectively vary the contributions of different atoms and absorption types (dipole versus quadrupole) to the measured total absorption spectrum. Iron K-edge absorption spectra in magnetite were studied in the presence of an XSW in an experiment conducted at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. This thesis presents an analysis of the data gathered during the experiment, with the goal of decomposing the experimentally measured pre-edge peak into its constituent components. The methods used in the analysis include principal component analysis and fitting predicted absorption peaks calculated with the Quanty software to the experimental data. The results show the dipole and quadrupole contributions of the tetrahedral sites responding to changes in the phase of the XSW in opposite ways in a manner consistent with theoretical predictions.

Particle Induced X-ray Emission (PIXE) was originally introduced as an ion-beam analytical technique in Lund in the 1970s and has since then been part of the available techniques in many laboratories around the world. The external beam PIXE set-up is used in probing the annual tree rings. The goal is to see the effects of volcanic eruption activities from the perspectives of tree plants here in Finland. In the theory part, I tried to include the description of how volcanoes are formed and created with a bit of volcanic activity history, the growth metabolism mechanism in tree plants and characteristics x-ray productions. The two tree sample used for this experiment were gotten from two different regions of Finland. The first tree is a Pine tree from Parikkala(a small place near Savolinna) in the south-eastern part of Finland and the second tree is a Spruce tree from Pielavesi (place near Kuopio) in the central part of Finland. These samples were carefully prepared for ionisation. The collected spectra data were analysed in a software called PyMCA. PyMCA has been developed by the Software Group of the European Synchrotron Radiation Facility (ESRF). PyMCA is a ready to use and in many aspects state-of-the-art, set of applications implementing most of the needs of X-ray fluorescence data analysis. PyMCA is use to interpret X-ray fluorescence spectra from a diverse array of samples

In condition-based maintenance data is collected from a machine to provide advice on frequency and location of developing faults. Statistical inference is needed to transform the data into information on the health of the machine. The ultimate goal is to minimise the machine down-time due to unexpected breakage. Predictive maintenance attempts to forecast the condition of the machine components from the observed data, and to maintain the machine just before it breaks down. The research question this thesis aims to solve is how to diagnose and predict component health based on data collected from the machine. Based on the literature, hidden Markov model is selected for further study. There is usually uncertainty relating to the parameters and structure of the model due to the complicated causal relationships in the modelling problem. Therefore the thesis concentrates in finding a suitable inference algorithm which is able to learn the model from data. Six different frequentist and Bayesian algorithms are tested with a synthetic example. A hypothesis is put forward that a hybrid genetic variational Bayesian algorithm could be used to find the best performing hidden Markov model of component health. As expected, the hybrid variational algorithm performs better than the other examined algorithms, especially when there is uncertainty relating to the model structure. However, since there typically is an imbalance between the data depicting faults and the data depicting the normal behaviour, the simulated test case shows that even the best performing variational algorithm has difficulties in identifying the correct model. This results in increased uncertainty in the health predictions. The thesis confirms that the hidden Markov model has many good qualities for modelling component health based on remote monitoring data. Due to the versatility of the model, it can be modified to account for the many details of component degradation behaviour in different machines.

As a company's Information Technology (IT) solutions become more complex, the importance of good IT support systems increases. The versatility of IT solutions in production environments is constantly increasing, as the systems are very long-lasting and increasingly incorporate technology. Carefully built support capability is able to take over the environment comprehensively, and provide support for cooperation between different stakeholders. This thesis lays the groundwork for a case company to enhance the support capabilities of IT services in production environments. In order for a comprehensive take-over to be successful, it is important to first understand what are the elements of the environment and what are their relationships to each other. Tools supporting environmental technology mapping will be developed to understand what kind of support would be needed at each point in time. The methods developed, as well as the definition of past problem cases and solutions collected through interviews. Based on the problems and solutions detected, we can build a framework of standard solutions: what type of standard solutions would improve the production support. Based on the standards, we are able to create a responsibility matrix that identifies stakeholders for the development of the standards. The research explores extensively the structure of IT services in production environments and the benefits of standardizing different aspects. Our case company is a major player in the defense industry, allowing us to figure out what kind of special requirements and characteristics exist in this closely controlled sector.

The techniques used to program quantum computers are somewhat crude. As quantum computing progresses and becomes mainstream, a more efficient method of programming these devices would be beneficial. We propose a method that applies today’s programming techniques to quantum computing, with program equivalence checking used to discern between code suited for execution on a conventional computer and a quantum computer. This process involves determining a quantum algorithm’s implementation using a programming language. This so-called benchmark implementation can be checked against code written by a programmer, with semantic equivalence between the two implying the programmer’s code should be executed on a quantum computer instead of a conventional computer. Using a novel compiler optimization verification tool named CORK, we test for semantic equivalence between a portion of Shor’s algorithm (representing the benchmark implementation) and various modified versions of this code (representing the arbitrary code written by a programmer). Some of the modified versions are intended to be semantically equivalent to the benchmark while others semantically inequivalent. Our testing shows that CORK is able to correctly determine semantic equivalence or semantic inequivalence in a majority of cases.

GPUs have become an important part of large-scale and high-performance physics simulations, due to their superior performance [11] and energy effiency [23] over CPUs. This thesis examines how to accelerate an existing CPU stencil code, that is originally parallelized through message passing, with GPUs. Our first research question is how to utilize the CPU cores alongside GPUs when the bulk of the computation is happening on GPUs. Secondly, we investigate how to address the performance bottleneck of data movement between CPU and GPU when there is a need to perform computational tasks originally intended to be executed on CPUs. Lastly, we investigate how the performance bottleneck of communication between processes can be alleviated to make better use of the available compute resources. In this thesis we approach these problems by building a preprocessor designed for making an existing CPU codebase suitable for GPU acceleration and the communication bottleneck is alleviated through extending a existing GPU oriented library Astaroth. We improve its task scheduling system and extend its own domain specific language (DSL) for stencil computations. Our solutions are demonstrated by making an existing CPU based astrophysics simulation code Pencil Code [4] suitable for GPU acceleration with the use of our preprocessor and the Astaroth library. Our results show that we are able to utilize CPU cores to perform useful work alongside the GPUs. We also show that we are able to circumvent the CPU-GPU data movement bottleneck by making code suitable for offloading through OpenMP offloading and code translation to GPU code. Lastly, we show that in certain cases Astaroth’s communication performance is increased by around 21% through smaller message sizes — with the added benefit of 14% lower memory usage, which corresponds to around 18% improvement in overall performance. Furthermore, we show benefits of the improved tasking and a identified memoryperformance trade-off.

Progressiivisen web-sovelluksen (Progressive Web Application, PWA) tarkoitus on hämärtää tai jo- pa poistaa raja sovelluskaupasta ladattavan sovelluksen ja normaalin verkkosivuston välillä. PWA- sovellus on kuin mikä tahansa normaali verkkosivusto, mutta se täyttää lisäksi seuraavat mitta- puut: Sovellus skaalautuu mille tahansa laitteelle. Sovellus tarjotaan salatun yhteyden yli. Sovellus on mahdollista asentaa puhelimen kotinäytölle pikakuvakkeeksi, jolloin sovellus avautuu ilman se- laimesta tuttuja navigointityökaluja ja lisäksi sovelluksen voi myös avata ilman verkkoyhteyttä. Tässä työssä käydään läpi PWA-sovelluksen rakennustekniikoita ja määritellään milloin sovellus on PWA-sovellus. Työssä mitataan PWA-sovelluksen nopeutta Service Workerin välimuistitallen- nusominaisuuksien ollessa käytössä ja ilman. PWA-sovelluksen luomista ja käyttöönottoa tarkastel- laan olemassa olevassa yksityisessä asiakasprojektissa. Projektin tarkastelussa kiinnitetään huomio- ta PWA-sovelluksen tuomiin etuihin ja kipupisteisiin. Tuloksen arvioimiseksi otetaan Google Chromen Lighthouse -työkalua käyttäen mittaukset sovel- luksen progressiivisuudesta ja nopeudesta. Lisäksi sovellusta vasten ajetaan Puppeteer-kirjastoa hyödyntäen latausnopeuden laskeva testi useita kertoja sekä tarkastellaan PWA-sovelluksen Service Workerin välimuistin hyödyllisyyttä suorituskyvyn ja latausajan kannalta. Jotta Service Workerin välimuistin käytöstä voidaan tehdä johtopäätökset, nopeuden muutosta tarkastellaan progressii- visten ominaisuuksien ollessa käytössä ja niiden ollessa pois päältä. Lisäksi tarkastellaan Googlen tapaustutkimuksen kautta Service Workerin vaikutuksia sovelluksen nopeuteen. Testitulokset osoittavat että Service Workerin välimuistin hyödyntäminen on nopeampaa kaikissa tapauksissa. Service Workerin välimuisti on nopeampi kuin selaimen oma välimuisti. Service Worker voi myös olla pysähtynyt ja odotustilassa käyttäjän selaimessa. Silti Service Workerin aktivoimi- nen ja välimuistin käyttäminen on nopeampaa kuin selaimen välimuistista tai suoraan verkosta lataaminen.

Named entity recognition is a challenging task in the field of NLP. As other machine learning problems, it requires a large amount of data for training a workable model. It is still a problem for languages such as Finnish due to the lack of data in linguistic resources. In this thesis, I propose an approach to automatic annotation in Finnish with limited linguistic rules and data of resource-rich language, English, as reference. Training with BiLSTM-CRF model, the preliminary result shows that automatic annotation can produce annotated instances with high accuracy and the model can achieve good performance for Finnish. In addition to automatic annotation and NER model training, to show the actual application of my Finnish NER model, two related experiments are conducted and discussed at the end of my thesis.

Pro gradu -tutkielma toteutettiin Kesko Oyj:n toimeksiantona. Toimeksiannossa tutkimuskohteena oli monivuotinen ja kolmivaiheinen cMDM-projekti, jonka tavoitteena oli selkeyttää asiakastietojen keräämistä, käyttämistä sekä asiakastietojen säilömistä. cMDM-projektin ensimmäinen vaihe oli jo vuonna 2013. Vaihe 2:si toteutettiin vuosina 2015 - 2016 ja vaihe 3 2/2018 - 4/2019. Pro gradu -tutkielmassa tutkimus toteutettiin kertomushaastattelemalla vaihe 2:n ja vaihe 3:n projektin avainasiantuntijoita. Kertomushaastatteluiden analysoinneilla tunnistettiin haasteita liittyen testaamiseen, projektivaiheesta ylläpitovaiheeseen siirtymisessä sekä henkilökunnan pysyvyyteen ylläpidossa. Tunnistettujen haasteiden perusteella Pro Gradu -tutkielmassa esitettiin ratkaisuehdotukset vaihe 2:n haasteiden välttämiseksi

The purpose of this work is to suggest an approach for holistical improvement of software development endeavor performance. The insights are a theory for mapping the key performance drivers of a software development system holistically, including the human centric factors that are involved in knowledge work, and a method for applying the theory in practice via a monitoring Instrument with case studies. The findings support that the theory complemented with the Instrument does provide holistic insights on a software development endeavor, reveals performance impediments and allows performance improvement efforts to be concentrated on the key performance drivers, i.e. where waste causes most performance decline. However further research is required for fine-tuning the Instrument for optimal performance indications. Suggestions for future work include an Instrument result coverage analysis and research on framework for quicker and easier analysis for more practical usage. Nevertheless, organizations can utilize the theory and the Instrument on as-is basis for improving software development performance without further research. The originality and value of this Thesis is centered on challenging the application of traditional management with its methods in software development endeavors and suggesting a new method for gaining higher production performance.