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The field of superhydrophobicity i.e. extreme water-repellency is a fast growing one ever since artificial ways of manufacturing such surfaces have been developed. Superhydrophobic surfaces have several potential applications including surfaces that are self-cleaning, corrosion and stain resistant, anti-fogging and anti-fouling. For the use of superhydrophobic surfaces in applications there is a need for a precise characterization of their wetting properties. However, conventional methods for characterization have several drawbacks when applied to superhydrophobic surfaces. This has resulted in a need to develop new method for characterizing wetting properties of superhydrophobic surfaces. This thesis presents one auspicious method for wetting characterization of ultra water-repellent surfaces along with the theory the method is based on. In the method a magnetic water droplet is forced to oscillate on the superhydrophobic surface. The friction affecting droplet during oscillations is proportional to the wetting degree of surface. Furthermore, using a moving droplet allows the investigation of dynamic wetting properties of superhydrophobic surfaces.

Kymmenottelu on yleisurheilulaji, joka koostu kymmenestä yksilölajista, jotka suoritetaan sa-massa järjestyksessä kahden vuorokauden aikana. Kymmenen lajin tulokset pisteytetään viralli-sen pistetaulukon mukaan ja lopputulos on näiden lajien yhteenlaskettu pistemäärä. Tutkielman tavoitteena on tutkia, mikä tekee huippuluokan kymmenottelijaa. Lisäksi tarkastellaan miten henkilökohtaiset kehityskäyrät vertautuvat lajeittain. Aineistona käytetään vuonna 1970-2019 yli 8 500 pisteen kymmenottelijoiden kaudenparhai-den ottelusarjassa tehtyjen tuloksien tietoja. Ottelijaprofiilin muutoksia tutkitaan neljässä tasos-sa. Erikseen tarkastellaan ottelijan henkilökohtainen kehitys lajeittain ja näiden mahdollisia ero-ja. Teoriaosassa käsitellään Lairdin ja Waren lineaarinen sekamalli (LME malli) sekä siihen liittyvä rajoitettu suuremman uskottavuuden menetelmää (REML). Tutkielman tuloksien valossa vaikuttaa siltä, että kymmenottelussa pikajuoksulajit ovat tär-keimmässä roolissa. Varsinkin lähtökohtaisesti heikoille 400 metrin juoksijoille kehitys on suu-ri. Kymmenottelijan profiilissa on havaittavissa, että tietyt lähtökohtaisesti heikot lajit pysyvät suhteellisen heikkona verrattuna muihin.

In the industry categorization, construction industry is one of the largest sources of waste and greenhouse gas emissions. Construction industry, with norms, practices, business models, and legislation connected to it, is built on linear foundations. In a linear economy, energy and material flows are based on value addition and a take-make-use-dispose logic. The circular economy is pursued as a replacement to the linear economic model and is based on the idea of value preservation. Among several other sustainability-driven concepts, the use of the concept of circular economy is growing in local, national and international level environmental governance. This thesis is located in the complex and ambiguous conceptual framework of circular economy as a sustainability transformation in municipal politics. The subjects under observation are four Finnish cities: Helsinki, Joensuu, Turku, and Vantaa. I aim to gain an understanding of why circular economy policy implementation in the construction and demolition of buildings seems inadequate in comparison to the municipalities’ circular economy and sustainability ambitions and whether it really is so. The current city strategies, the policy documents with the most significant guiding impact to circular construction, and interviews with experts from the municipalities and construction sector are analyzed with thematic analysis. This thesis is a part of a six-year transdisciplinary research project, DeCarbon-Home, which studies and co-develops solutions to the just sustainability transitions of living and construction. The results of this thesis show that the understanding and awareness of the concept of circular economy and ambitions attached to it vary significantly not only between cities but also within. The cities are in different phases of circular economy transition, and the results demonstrate various pathways of policy implementation. Some shared challenges that are so far hindering the cities from implementing circularity in construction have to do with the lock-in with the current linear system, division of ownership and responsibility, communication, timing, and paradigm shift.

The thesis consists of presenting and analysing the original proof for the Embedding Theorem that Hassler Whitney gave in his 1936 article Differentiable Manifolds. The embedding theorem states that given an m-dimensional Cr-differentiable (r ≥ 1) manifold M, it is possible to embed it in Euclidean space Rn, if n ≥ 2m + 1. Embedding is defined as a mapping f : M → Rn which is Cr-smooth, bijective immersion that is homeomorphism to its image f[M]. Whitney’s proof rests on few important novel concepts and a series of lemmas in relation to them. These concepts include the concept of the k-extent of a set, a sort of a k-dimensional measure in an n-dimensional space; the concept of Cr-function g : M → N approximating (f, M, r, η), where f is a Cr-function f : M → N, η an error function; and the concept of (f, r, η)-properties defined for such g. Outstanding lemmas of general nature are Lemma 7: If f : M → N is a Cr-map and A ⊂ M is of finite (zero) k-extent, then f[A] is of finite (zero) k-extent. Lemma 8: For open sets R and R′ of Rm and Rh, if {Tα} is a h-parameter family of C1-maps of R ⊂ Rm into Rn, and A ⊂ R and B ⊂ Rn closed subsets, such that A is of finite k-extent and B of zero (h − k)-extent, then for some α ∈ R′, Tα[A] does not intersect B. Lemma 9: If f : M → N is a Cr-map, η positive continuous function in M, Ω1, Ω2, . . . are (f, r, η)- properties, then there is a Cr-map F : M → N which approximates (f, M, r, η) and has properties Ω1, Ω2, . . . . Lemmas 11 and 12 then show that bijectivity and immersion property are the logical sum of countable number of (f, r, η)-properties. These facts are used in finding an embedding F : M → Rn by perturbing a given smooth function f : M → Rn. Detailed treatment of all proofs is provided. Adjustments to the proofs are made where deemed necessary; auxiliary assumptions are made where they seem to be required. Clarifications and proofs are given to facts noted but not proven in the article

The liberal peace paradigm focusing on a top-down approach and implementing Western values in a one-fits-all model dominated the field of peacekeeping and crisis management missions especially from the 1980s onwards. Later, local ownership became a “buzzword” in international interventions after some major failures of peacekeeping missions in the 1990s and early 2000s. Since then highlighting the relevance of the inclusion of local actors and of utilizing local knowledge have become inseparable parts of the major international organizations’ policy documents and strategies dealing with crisis management and peacebuilding. However, the definition of who or where is local has not been adequately addressed. This has led to using the local as a concept referring to almost anything and everything within the borders of a state. The vague conceptualization has been criticized by scholars, as it leaves unanswered many questions about who can represent local interests or which actors should be included in a crisis management process to increase the sustainability of the intervention. This Master’s thesis seeks research on who, what or where the local level is seen to be in the context of the EU’s civilian crisis management. It does it by uncovering and discussing discourses of the local level from a set of the EU’s documents dealing with civilian crisis management or external action more generally. In this thesis the local level is framed as a social construction through the notion of scale and level from human geographical literature. The human geographical literature also highlights the importance of not only looking at the discourses of the local level but also how it relates to other levels to gain a fuller understanding. The thesis also discusses the potential political opportunity structures that follow from these discourses. There are three main discourses found in the documents focusing on who the local level comprises of: authorities and government, civil society and a variety of different actors on different levels within the nation. None of these discourses raises above the others. Instead, they co-exist, leaving the local level vaguely defined. It is argued that this gives the EU an opportunity to pick the local actors to cooperate with case-by-case. This choice can reflect the needs and will of the EU, the host country or both. In addition, two discourses relating to what the local level represents more generally were discovered. These form a dichotomy: the local is seen both as a threat to the security of the EU citizens but simultaneously as a necessity to include in missions to increase the effectiveness of CSDP missions. Overall, the importance of local ownership is highlighted throughout the documents. Considering this, the low level of mentions of local actors is somewhat surprising as well as the vague definition of who or where is local.

This study evaluates how the advection of precipitation, or wind drift, between the radar volume and ground affects radar measurements of precipitation. Normally precipitation is assumed to fall vertically to the ground from the contributing volume, and thus the radar measurement represents the geographical location immediately below. In this study radar measurements are corrected using hydrometeor trajectories calculated from measured and forecasted winds, and the effect of trajectory-correction on the radar measurements is evaluated. Wind drift statistics for Finland are compiled using sounding data from two weather stations spanning two years. For each sounding, the hydrometeor phase at ground level is estimated and drift distance calculated using different originating level heights. This way the drift statistics are constructed as a function of range from radar and elevation angle. On average, wind drift of 1 km was exceeded at approximately 60 km distance, while drift of 10 km was exceeded at 100 km distance. Trajectories were calculated using model winds in order to produce a trajectory-corrected ground field from radar PPI images. It was found that at the upwind side from the radar the effective measuring area was reduced as some trajectories exited the radar volume scan. In the downwind side areas near the edge of the radar measuring area experience improved precipitation detection. The effect of trajectory-correction is most prominent in instant measurements and diminishes when accumulating over longer time periods. Furthermore, measurements of intensive and small scale precipitation patterns benefit most from wind drift correction. The contribution of wind drift on the uncertainty of estimated Ze (S) - relationship was studied by simulating the effect of different error sources to the uncertainty in the relationship coefficients a and b. The overall uncertainty was assumed to consist of systematic errors of both the radar and the gauge, as well as errors by turbulence at the gauge orifice and by wind drift of precipitation. The focus of the analysis is error associated with wind drift, which was determined by describing the spatial structure of the reflectivity field using spatial autocovariance (or variogram). This spatial structure was then used with calculated drift distances to estimate the variance in radar measurement produced by precipitation drift, relative to the other error sources. It was found that error by wind drift was of similar magnitude with error by turbulence at gauge orifice at all ranges from radar, with systematic errors of the instruments being a minor issue. The correction method presented in the study could be used in radar nowcasting products to improve the estimation of visibility and local precipitation intensities. The method however only considers pure snow, and for operational purposes some improvements are desirable, such as melting layer detection, VPR correction and taking solid state hydrometeor type into account, which would improve the estimation of vertical velocities of the hydrometeors.

Wolfe’s Theorem states that there is an isometric isomorphism between the space of flat k-cochains and the flat differential k-forms in R^n . The flat forms are the space of essentially bounded differential forms with an essentially bounded weak exterior derivative. The flat cochains are the dual space of the flat chains which are geometric objects based on finite linear combinations of k-simplices. In this sense, Wolfe’s Theorem connects geometry and analysis. After proving Wolfe’s Theorem, we give two corollaries: that the isomorphism from Wolfe’s Theorem can be concretely approximated by convolution with smooth mollifiers, and a version of Stokes’ Theorem for flat chains. Our method for proving Wolfe’s Theorem involves isometrically embedding the flat chains, as well as a predual of the flat forms, into the space of flat currents. By way of some approximation theorems in the space of flat currents, the images of these two embeddings coincide. Thus, the flat chains are isomorphic to that predual. This isomorphism lifts to their dual spaces giving Wolfe’s Theorem.

Säätutkia käytetään sadealueiden liikkeiden ja sateen voimakkuuden arvioimisen. Säätutkan toimintaperiaate perustuu sille, että sen lähettämä mikroaaltopulssi siroaa ilmakehässä olevista partikkeleista kuten vesipisaroista ympäristöönsä, jolloin pieni osa lähetetystä pulssista heijastuu takaisin kohti tutkaa. Tutka vastaanottaa palanneen pulssin ja arvioi sen perusteella sadealueita. Säätutkat ovat mittalaitteita, jotka vaativat toimiakseen säännöllistä huoltoa ja mittaustulosten validointia. Säätutkan kalibrointi on monessa mielessä haasteellista. Tutka on kaukokartoituslaite, jonka keräämä data kattaa alueen aina 250 km säteelle tutkasta. Se ei mittaa suoraan sademäärää, kuten sademittarit yleensä, vaan arvio sen välillisesti tutkaheijastuvuuden kautta. Tämän tutkimuksen tarkoitus on tarkastella uutta mahdollista kalibrointimenetelmää. Uusi menetelmä käyttäisi pienoissadetutkaa MRR-2 vertailukohtana. Myös MRR-2 mittaa tutkaheijastuvuustekijää, joten se voisi olla hyvä vertailupari säätutkalle. Tasaisen sateen otoksessa vuosien 2015-2018 kesäsateissa säätutkan WRM200 ja pienoissadetutkan MRR-2 vertailupisteihin sovitetun suoran yhtälö on 𝑍(𝑊𝑅𝑀200) = 0.83 𝑍(𝑀𝑅𝑅−2) + 2.01, jossa 𝑍(𝑊𝑅𝑀200) on säätutkan ja 𝑍(𝑀𝑅𝑅−2) on pienoissadetutkan mittaama tutkaheijastuvuustekijä. Tasaisessa sateessa otoksen RMS-virhe on 3,36 dB. Konvektiivisen sateen otoksessa vastaava yhtälö on 𝑍(𝑊𝑅𝑀200) = 0.77 𝑍(𝑀𝑅𝑅−2) + 3.70 ja RMS-virhe 5,36 dB. Tasaisessa sateessa verrattavuus on konvektiivisessa sateessa tehtyä vertailua parempi. Tutkimus sisältää pohdintaa tuloksiin vaikuttavista tekijöistä sekä pohdintaa MRR-2:n soveltuvuudesta vertailulaitteeksi säätutkan kalibrointiin. Tutkimuksen pohjalta vaikuttaa siltä, että vaikka vertailunasettelu pyritään tehdä mahdollisimman vakaaksi, ei virhetekijöitä voida sulkea pois. Näin ollen tämän kaltaisella asettelulla ei voida suorittaa tarkkaa säätutkan kalibrointia.

Lithium ion batteries (LIBs) are used as power sources in most of portable devices, electronic cars and many other applications today. As the industry demands for smaller devices, new focus has raised for nanostructured electrodes and all solid state batteries. LIBs are rechargeable batteries, which means that Li+-ions migrate between anode and cathode reversibly. For the battery to work, the electrodes need to be stable when Li+-ions are intercalated and removed from the structure. LiMn2O4 is a promising material for a cathode, because the three-dimensional manganese oxide network enables intercalation of additional lithium ions also beyond the 1:1 Li:Mn stoichiometry resulting in structures in the range of LixMn2O4, 0 ≤ x ≤ 2. The non-stoichiometric behavior improves the specific capacity of the battery compared to other possible lithium intercalation cathode materials like LiCoO2 and LiNiO2. Atomic layer deposition (ALD) is a gas phase thin film deposition technique where the precursors are led to react on the surface one by one. Because no chemical reaction is taking place in the gas phase, the film growth is highly controllable and the resulting films have excellent purity and high uniformity and conformity. ALD is superior thin film deposition technique even on top of 3D structures and when depositing ultra-thin films. This makes it excellent technique to deposit electrode materials for LIBs. X-ray absorption spectroscopy (XAS) measures the absorption of the material as a function of x-ray energy. With a tunable light source it is possible to study a selected electron core shell of a specific element. XAS gives then information on the electronic structure as well as the local crystal structure of the selected atom in the material. Therefore, XAS is an excellent technique for studying the intercalation and de-intercalation processes of LiMn2O4. The literature part of this thesis describes the synthesis of LiMn2O4 thin films and the behavior of the material as a working cathode in LIB. The focus is especially on XAS studies on LiMn2O4. The experimental part involves a study on ALD grown β-MnO2 and LixMn2O4, 0 ≤ x ≤ 1, thin films with XAS, X-ray diffraction (XRD), X-ray reflectivity (XRR), time-of-flight elastic recoil detection analysis (TOF-ERDA), residual stress measurements and X-ray photoelectron spectroscopy (XPS). The aim of the study was to define how and where Li+ -ions intercalate in the β-MnO2 structure. To clarify the intercalation process, K and L core shells of manganese and K core shell of oxygen were studied with XAS. Samples were prepared at 225 ˚C by using earlier known ALD processes. First β-MnO2 film was deposited and then lithium was added by pulsing LiOtBu and H2O alternately on to the β-MnO2 film. The films were annealed after the deposition, however the lithium intercalation was observed to start already during the LiOtBu – H2O pulsing sequence. For the lithium intercalation mechanism, it is proposed that in the beginning the Li+-ions penetrate only to the top part of the β-MnO2 film and a lithium deficient non-stoichiometric phase LixMn2O4, 0 < x < 0.5, is formed. When the lithium concentration exceeds x ≈ 0.5 in LixMn2O4, the phase changes from the tetragonal pyrolusite to the cubic spinel, which enables Li+-ions to migrate throughout the whole film. Annealing in air after deposition seemed to convert the phase completely to the pure cubic spinel LiMn2O4.

X-ray emission spectroscopy (XES) is an elemental characteristic x-ray technique that is used in studying the electronic properties of varied materials. It is based on an x-ray emission process that occurs due to an absorption process. First an x-ray photon is shot at the sample and electron in the inner core absorbs this x-ray photon. The electron gets kicked out of its place, creating an empty electronic state called an electron hole. This leaves the atom to an excited state that then de-excites by emitting an elemental characteristic x-ray photon. One of the main aspects of x-ray emission spectroscopy is to study sensitivity of XES towards different emission lines in different chemical environments and then compare the results. X-ray emission spectroscopy is a relatively easy technique to perform because it does not require a long-range crystal order and experiments can be done in an atmospheric pressure and in room temperature. A series of measurements were performed with non-resonant XES to study chemical properties of different uranium oxides. The experiment was done at the SOLEIL Synchrotron Facility in France. Main goal of the experiment was to study the sensitivity of XES to different uranium L3-emission lines by measuring different uranium oxides with different uranium oxidation states and compare the shape of each emission spectrum. The results showed that there are no visible differences between different samples when using non-resonant XES. However, the experiment also showed that when the resonant part is included in the measurements, then there are visible differences between different samples. This indicates the resonant part is required to collect to see differences in the spectrum when comparing the speciation of different samples.