954 resultados para Distribution system operation


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In distributed energy production, permanent magnet synchronous generators (PMSG) are often connected to the grid via frequency converters, such as voltage source line converters. The price of the converter may constitute a large part of the costs of a generating set. Some of the permanent magnet synchronous generators with converters and traditional separately excited synchronous generators couldbe replaced by direct-on-line (DOL) non-controlled PMSGs. Small directly networkconnected generators are likely to have large markets in the area of distributed electric energy generation. Typical prime movers could be windmills, watermills and internal combustion engines. DOL PMSGs could also be applied in island networks, such as ships and oil platforms. Also various back-up power generating systems could be carried out with DOL PMSGs. The benefits would be a lower priceof the generating set and the robustness and easy use of the system. The performance of DOL PMSGs is analyzed. The electricity distribution companies have regulations that constrain the design of the generators being connected to the grid. The general guidelines and recommendations are applied in the analysis. By analyzing the results produced by the simulation model for the permanent magnet machine, the guidelines for efficient damper winding parameters for DOL PMSGs are presented. The simulation model is used to simulate grid connections and load transients. The damper winding parameters are calculated by the finite element method (FEM) and determined from experimental measurements. Three-dimensional finite element analysis (3D FEA) is carried out. The results from the simulation model and 3D FEA are compared with practical measurements from two prototype axial flux permanent magnet generators provided with damper windings. The dimensioning of the damper winding parameters is case specific. The damper winding should be dimensioned based on the moment of inertia of the generating set. It is shown that the damper winding has optimal values to reach synchronous operation in the shortest period of time after transient operation. With optimal dimensioning, interferenceon the grid is minimized.

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Väitöstutkimuksessa on tarkasteltuinfrapunaspektroskopian ja monimuuttujaisten aineistonkäsittelymenetelmien soveltamista kiteytysprosessin monitoroinnissa ja kidemäisen tuotteen analysoinnissa. Parhaillaan kiteytysprosessitutkimuksessa maailmanlaajuisesti tutkitaan intensiivisesti erilaisten mittausmenetelmien soveltamista kiteytysprosessin ilmiöidenjatkuvaan mittaamiseen niin nestefaasista kuin syntyvistä kiteistäkin. Lisäksi tuotteen karakterisointi on välttämätöntä tuotteen laadun varmistamiseksi. Erityisesti lääkeaineiden valmistuksessa kiinnostusta tämäntyyppiseen tutkimukseen edistää Yhdysvaltain elintarvike- ja lääkeaineviraston (FDA) prosessianalyyttisiintekniikoihin (PAT) liittyvä ohjeistus, jossa määritellään laajasti vaatimukset lääkeaineiden valmistuksessa ja tuotteen karakterisoinnissa tarvittaville mittauksille turvallisten valmistusprosessien takaamiseksi. Jäähdytyskiteytyson erityisesti lääketeollisuudessa paljon käytetty erotusmenetelmä kiinteän raakatuotteen puhdistuksessa. Menetelmässä puhdistettava kiinteä raaka-aine liuotetaan sopivaan liuottimeen suhteellisen korkeassa lämpötilassa. Puhdistettavan aineen liukoisuus käytettävään liuottimeen laskee lämpötilan laskiessa, joten systeemiä jäähdytettäessä liuenneen aineen konsentraatio prosessissa ylittää liukoisuuskonsentraation. Tällaiseen ylikylläiseen systeemiin pyrkii muodostumaan uusia kiteitä tai olemassa olevat kiteet kasvavat. Ylikylläisyys on yksi tärkeimmistä kidetuotteen laatuun vaikuttavista tekijöistä. Jäähdytyskiteytyksessä syntyvän tuotteen ominaisuuksiin voidaan vaikuttaa mm. liuottimen valinnalla, jäähdytyprofiililla ja sekoituksella. Lisäksi kiteytysprosessin käynnistymisvaihe eli ensimmäisten kiteiden muodostumishetki vaikuttaa tuotteen ominaisuuksiin. Kidemäisen tuotteen laatu määritellään kiteiden keskimääräisen koon, koko- ja muotojakaumansekä puhtauden perusteella. Lääketeollisuudessa on usein vaatimuksena, että tuote edustaa tiettyä polymorfimuotoa, mikä tarkoittaa molekyylien kykyä järjestäytyä kidehilassa usealla eri tavalla. Edellä mainitut ominaisuudet vaikuttavat tuotteen jatkokäsiteltävyyteen, kuten mm. suodattuvuuteen, jauhautuvuuteen ja tabletoitavuuteen. Lisäksi polymorfiamuodolla on vaikutusta moniin tuotteen käytettävyysominaisuuksiin, kuten esim. lääkeaineen liukenemisnopeuteen elimistössä. Väitöstyössä on tutkittu sulfatiatsolin jäähdytyskiteytystä käyttäen useita eri liuotinseoksia ja jäähdytysprofiileja sekä tarkasteltu näiden tekijöiden vaikutustatuotteen laatuominaisuuksiin. Infrapunaspektroskopia on laajalti kemian alan tutkimuksissa sovellettava menetelmä. Siinä mitataan tutkittavan näytteenmolekyylien värähtelyjen aiheuttamia spektrimuutoksia IR alueella. Tutkimuksessa prosessinaikaiset mittaukset toteutettiin in-situ reaktoriin sijoitettavalla uppoanturilla käyttäen vaimennettuun kokonaisheijastukseen (ATR) perustuvaa Fourier muunnettua infrapuna (FTIR) spektroskopiaa. Jauhemaiset näytteet mitattiin off-line diffuusioheijastukseen (DRIFT) perustuvalla FTIR spektroskopialla. Monimuuttujamenetelmillä (kemometria) voidaan useita satoja, jopa tuhansia muuttujia käsittävä spektridata jalostaa kvalitatiiviseksi (laadulliseksi) tai kvantitatiiviseksi (määrälliseksi) prosessia kuvaavaksi informaatioksi. Väitöstyössä tarkasteltiin laajasti erilaisten monimuuttujamenetelmien soveltamista mahdollisimman monipuolisen prosessia kuvaavan informaation saamiseksi mitatusta spektriaineistosta. Väitöstyön tuloksena on ehdotettu kalibrointirutiini liuenneen aineen konsentraation ja edelleen ylikylläisyystason mittaamiseksi kiteytysprosessin aikana. Kalibrointirutiinin kehittämiseen kuuluivat aineiston hyvyyden tarkastelumenetelmät, aineiston esikäsittelymenetelmät, varsinainen kalibrointimallinnus sekä mallin validointi. Näin saadaan reaaliaikaista informaatiota kiteytysprosessin ajavasta voimasta, mikä edelleen parantaa kyseisen prosessin tuntemusta ja hallittavuutta. Ylikylläisyystason vaikutuksia syntyvän kidetuotteen laatuun seurattiin usein kiteytyskokein. Työssä on esitetty myös monimuuttujaiseen tilastolliseen prosessinseurantaan perustuva menetelmä, jolla voidaan ennustaa spontaania primääristä ytimenmuodostumishetkeä mitatusta spektriaineistosta sekä mahdollisesti päätellä ydintymisessä syntyvä polymorfimuoto. Ehdotettua menetelmää hyödyntäen voidaan paitsi ennakoida kideytimien muodostumista myös havaita mahdolliset häiriötilanteet kiteytysprosessin alkuhetkillä. Syntyvää polymorfimuotoa ennustamalla voidaan havaita ei-toivotun polymorfin ydintyminen,ja mahdollisesti muuttaa kiteytyksen ohjausta halutun polymorfimuodon saavuttamiseksi. Monimuuttujamenetelmiä sovellettiin myös kiteytyspanosten välisen vaihtelun määrittämiseen mitatusta spektriaineistosta. Tämäntyyppisestä analyysistä saatua informaatiota voidaan hyödyntää kiteytysprosessien suunnittelussa ja optimoinnissa. Väitöstyössä testattiin IR spektroskopian ja erilaisten monimuuttujamenetelmien soveltuvuutta kidetuotteen polymorfikoostumuksen nopeaan määritykseen. Jauhemaisten näytteiden luokittelu eri polymorfeja sisältäviin näytteisiin voitiin tehdä käyttäen tarkoitukseen soveltuvia monimuuttujaisia luokittelumenetelmiä. Tämä tarjoaa nopean menetelmän jauhemaisen näytteen polymorfikoostumuksen karkeaan arviointiin, eli siihen mitä yksittäistä polymorfia kyseinen näyte pääasiassa sisältää. Varsinainen kvantitatiivinen analyysi, eli sen selvittäminen paljonko esim. painoprosentteina näyte sisältää eri polymorfeja, vaatii kaikki polymorfit kattavan fysikaalisen kalibrointisarjan, mikä voi olla puhtaiden polymorfien huonon saatavuuden takia hankalaa.

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Dynamic behavior of bothisothermal and non-isothermal single-column chromatographic reactors with an ion-exchange resin as the stationary phase was investigated. The reactor performance was interpreted by using results obtained when studying the effect of the resin properties on the equilibrium and kinetic phenomena occurring simultaneously in the reactor. Mathematical models were derived for each phenomenon and combined to simulate the chromatographic reactor. The phenomena studied includes phase equilibria in multicomponent liquid mixture¿ion-exchange resin systems, chemicalequilibrium in the presence of a resin catalyst, diffusion of liquids in gel-type and macroporous resins, and chemical reaction kinetics. Above all, attention was paid to the swelling behavior of the resins and how it affects the kinetic phenomena. Several poly(styrene-co-divinylbenzene) resins with different cross-link densities and internal porosities were used. Esterification of acetic acid with ethanol to produce ethyl acetate and water was used as a model reaction system. Choosing an ion-exchange resin with a low cross-link density is beneficial inthe case of the present reaction system: the amount of ethyl acetate as well the ethyl acetate to water mole ratio in the effluent stream increase with decreasing cross-link density. The enhanced performance of the reactor is mainly attributed to increasing reaction rate, which in turn originates from the phase equilibrium behavior of the system. Also mass transfer considerations favor the use ofresins with low cross-link density. The diffusion coefficients of liquids in the gel-type ion-exchange resins were found to fall rapidly when the extent of swelling became low. Glass transition of the polymer was not found to significantlyretard the diffusion in sulfonated PS¿DVB ion-exchange resins. It was also shown that non-isothermal operation of a chromatographic reactor could be used to significantly enhance the reactor performance. In the case of the exothermic modelreaction system and a near-adiabatic column, a positive thermal wave (higher temperature than in the initial state) was found to travel together with the reactive front. This further increased the conversion of the reactants. Diffusion-induced volume changes of the ion-exchange resins were studied in a flow-through cell. It was shown that describing the swelling and shrinking kinetics of the particles calls for a mass transfer model that explicitly includes the limited expansibility of the polymer network. A good description of the process was obtained by combining the generalized Maxwell-Stefan approach and an activity model that was derived from the thermodynamics of polymer solutions and gels. The swelling pressure in the resin phase was evaluated by using a non-Gaussian expression forthe polymer chain length distribution. Dimensional changes of the resin particles necessitate the use of non-standard mathematical tools for dynamic simulations. A transformed coordinate system, where the mass of the polymer was used as a spatial variable, was applied when simulating the chromatographic reactor columns as well as the swelling and shrinking kinetics of the resin particles. Shrinking of the particles in a column leads to formation of dead volume on top of the resin bed. In ordinary Eulerian coordinates, this results in a moving discontinuity that in turn causes numerical difficulties in the solution of the PDE system. The motion of the discontinuity was eliminated by spanning two calculation grids in the column that overlapped at the top of the resin bed. The reactive and non-reactive phase equilibrium data were correlated with a model derived from thethermodynamics of polymer solution and gels. The thermodynamic approach used inthis work is best suited at high degrees of swelling because the polymer matrixmay be in the glassy state when the extent of swelling is low.

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1. Introduction "The one that has compiled ... a database, the collection, securing the validity or presentation of which has required an essential investment, has the sole right to control the content over the whole work or over either a qualitatively or quantitatively substantial part of the work both by means of reproduction and by making them available to the public", Finnish Copyright Act, section 49.1 These are the laconic words that implemented the much-awaited and hotly debated European Community Directive on the legal protection of databases,2 the EDD, into Finnish Copyright legislation in 1998. Now in the year 2005, after more than half a decade of the domestic implementation it is yet uncertain as to the proper meaning and construction of the convoluted qualitative criteria the current legislation employs as a prerequisite for the database protection both in Finland and within the European Union. Further, this opaque Pan-European instrument has the potential of bringing about a number of far-reaching economic and cultural ramifications, which have remained largely uncharted or unobserved. Thus the task of understanding this particular and currently peculiarly European new intellectual property regime is twofold: first, to understand the mechanics and functioning of the EDD and second, to realise the potential and risks inherent in the new legislation in economic, cultural and societal dimensions. 2. Subject-matter of the study: basic issues The first part of the task mentioned above is straightforward: questions such as what is meant by the key concepts triggering the functioning of the EDD such as presentation of independent information, what constitutes an essential investment in acquiring data and when the reproduction of a given database reaches either qualitatively or quantitatively the threshold of substantiality before the right-holder of a database can avail himself of the remedies provided by the statutory framework remain unclear and call for a careful analysis. As for second task, it is already obvious that the practical importance of the legal protection providedby the database right is in the rapid increase. The accelerating transformationof information into digital form is an existing fact, not merely a reflection of a shape of things to come in the future. To take a simple example, the digitisation of a map, traditionally in paper format and protected by copyright, can provide the consumer a markedly easier and faster access to the wanted material and the price can be, depending on the current state of the marketplace, cheaper than that of the traditional form or even free by means of public lending libraries providing access to the information online. This also renders it possible for authors and publishers to make available and sell their products to markedly larger, international markets while the production and distribution costs can be kept at minimum due to the new electronic production, marketing and distributionmechanisms to mention a few. The troublesome side is for authors and publishers the vastly enhanced potential for illegal copying by electronic means, producing numerous virtually identical copies at speed. The fear of illegal copying canlead to stark technical protection that in turn can dampen down the demand for information goods and services and furthermore, efficiently hamper the right of access to the materials available lawfully in electronic form and thus weaken the possibility of access to information, education and the cultural heritage of anation or nations, a condition precedent for a functioning democracy. 3. Particular issues in Digital Economy and Information Networks All what is said above applies a fortiori to the databases. As a result of the ubiquity of the Internet and the pending breakthrough of Mobile Internet, peer-to-peer Networks, Localand Wide Local Area Networks, a rapidly increasing amount of information not protected by traditional copyright, such as various lists, catalogues and tables,3previously protected partially by the old section 49 of the Finnish Copyright act are available free or for consideration in the Internet, and by the same token importantly, numerous databases are collected in order to enable the marketing, tendering and selling products and services in above mentioned networks. Databases and the information embedded therein constitutes a pivotal element in virtually any commercial operation including product and service development, scientific research and education. A poignant but not instantaneously an obvious example of this is a database consisting of physical coordinates of a certain selected group of customers for marketing purposes through cellular phones, laptops and several handheld or vehicle-based devices connected online. These practical needs call for answer to a plethora of questions already outlined above: Has thecollection and securing the validity of this information required an essential input? What qualifies as a quantitatively or qualitatively significant investment? According to the Directive, the database comprises works, information and other independent materials, which are arranged in systematic or methodical way andare individually accessible by electronic or other means. Under what circumstances then, are the materials regarded as arranged in systematic or methodical way? Only when the protected elements of a database are established, the question concerning the scope of protection becomes acute. In digital context, the traditional notions of reproduction and making available to the public of digital materials seem to fit ill or lead into interpretations that are at variance with analogous domain as regards the lawful and illegal uses of information. This may well interfere with or rework the way in which the commercial and other operators have to establish themselves and function in the existing value networks of information products and services. 4. International sphere After the expiry of the implementation period for the European Community Directive on legal protection of databases, the goals of the Directive must have been consolidated into the domestic legislations of the current twenty-five Member States within the European Union. On one hand, these fundamental questions readily imply that the problemsrelated to correct construction of the Directive underlying the domestic legislation transpire the national boundaries. On the other hand, the disputes arisingon account of the implementation and interpretation of the Directive on the European level attract significance domestically. Consequently, the guidelines on correct interpretation of the Directive importing the practical, business-oriented solutions may well have application on European level. This underlines the exigency for a thorough analysis on the implications of the meaning and potential scope of Database protection in Finland and the European Union. This position hasto be contrasted with the larger, international sphere, which in early 2005 does differ markedly from European Union stance, directly having a negative effect on international trade particularly in digital content. A particular case in point is the USA, a database producer primus inter pares, not at least yet having aSui Generis database regime or its kin, while both the political and academic discourse on the matter abounds. 5. The objectives of the study The above mentioned background with its several open issues calls for the detailed study of thefollowing questions: -What is a database-at-law and when is a database protected by intellectual property rights, particularly by the European database regime?What is the international situation? -How is a database protected and what is its relation with other intellectual property regimes, particularly in the Digital context? -The opportunities and threats provided by current protection to creators, users and the society as a whole, including the commercial and cultural implications? -The difficult question on relation of the Database protection and protection of factual information as such. 6. Dsiposition The Study, in purporting to analyse and cast light on the questions above, is divided into three mainparts. The first part has the purpose of introducing the political and rationalbackground and subsequent legislative evolution path of the European database protection, reflected against the international backdrop on the issue. An introduction to databases, originally a vehicle of modern computing and information andcommunication technology, is also incorporated. The second part sets out the chosen and existing two-tier model of the database protection, reviewing both itscopyright and Sui Generis right facets in detail together with the emergent application of the machinery in real-life societal and particularly commercial context. Furthermore, a general outline of copyright, relevant in context of copyright databases is provided. For purposes of further comparison, a chapter on the precursor of Sui Generi, database right, the Nordic catalogue rule also ensues. The third and final part analyses the positive and negative impact of the database protection system and attempts to scrutinize the implications further in the future with some caveats and tentative recommendations, in particular as regards the convoluted issue concerning the IPR protection of information per se, a new tenet in the domain of copyright and related rights.

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The objective of industrial crystallization is to obtain a crystalline product which has the desired crystal size distribution, mean crystal size, crystal shape, purity, polymorphic and pseudopolymorphic form. Effective control of the product quality requires an understanding of the thermodynamics of the crystallizing system and the effects of operation parameters on the crystalline product properties. Therefore, obtaining reliable in-line information about crystal properties and supersaturation, which is the driving force of crystallization, would be very advantageous. Advanced techniques, such asRaman spectroscopy, attenuated total reflection Fourier transform infrared (ATR FTIR) spectroscopy, and in-line imaging techniques, offer great potential for obtaining reliable information during crystallization, and thus giving a better understanding of the fundamental mechanisms (nucleation and crystal growth) involved. In the present work, the relative stability of anhydrate and dihydrate carbamazepine in mixed solvents containing water and ethanol were investigated. The kinetics of the solvent mediated phase transformation of the anhydrate to hydrate in the mixed solvents was studied using an in-line Raman immersion probe. The effects of the operation parameters in terms of solvent composition, temperature and the use of certain additives on the phase transformation kineticswere explored. Comparison of the off-line measured solute concentration and the solid-phase composition measured by in-line Raman spectroscopy allowedthe identification of the fundamental processes during the phase transformation. The effects of thermodynamic and kinetic factors on the anhydrate/hydrate phase of carbamazepine crystals during cooling crystallization were also investigated. The effect of certain additives on the batch cooling crystallization of potassium dihydrogen phosphate (KDP) wasinvestigated. The crystal growth rate of a certain crystal face was determined from images taken with an in-line video microscope. An in-line image processing method was developed to characterize the size and shape of thecrystals. An ATR FTIR and a laser reflection particle size analyzer were used to study the effects of cooling modes and seeding parameters onthe final crystal size distribution of an organic compound C15. Based on the obtained results, an operation condition was proposed which gives improved product property in terms of increased mean crystal size and narrowersize distribution.

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Background: Optimization methods allow designing changes in a system so that specific goals are attained. These techniques are fundamental for metabolic engineering. However, they are not directly applicable for investigating the evolution of metabolic adaptation to environmental changes. Although biological systems have evolved by natural selection and result in well-adapted systems, we can hardly expect that actual metabolic processes are at the theoretical optimum that could result from an optimization analysis. More likely, natural systems are to be found in a feasible region compatible with global physiological requirements. Results: We first present a new method for globally optimizing nonlinear models of metabolic pathways that are based on the Generalized Mass Action (GMA) representation. The optimization task is posed as a nonconvex nonlinear programming (NLP) problem that is solved by an outer- approximation algorithm. This method relies on solving iteratively reduced NLP slave subproblems and mixed-integer linear programming (MILP) master problems that provide valid upper and lower bounds, respectively, on the global solution to the original NLP. The capabilities of this method are illustrated through its application to the anaerobic fermentation pathway in Saccharomyces cerevisiae. We next introduce a method to identify the feasibility parametric regions that allow a system to meet a set of physiological constraints that can be represented in mathematical terms through algebraic equations. This technique is based on applying the outer-approximation based algorithm iteratively over a reduced search space in order to identify regions that contain feasible solutions to the problem and discard others in which no feasible solution exists. As an example, we characterize the feasible enzyme activity changes that are compatible with an appropriate adaptive response of yeast Saccharomyces cerevisiae to heat shock Conclusion: Our results show the utility of the suggested approach for investigating the evolution of adaptive responses to environmental changes. The proposed method can be used in other important applications such as the evaluation of parameter changes that are compatible with health and disease states.

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La distribución del número y del volumen de partículas, y la eficiencia de eliminación de las partículas y los sólidos en suspensión de diferentes efluentes y sus filtrados, fueron analizadas para estudiar si los filtros más usuales en los sistemas de riego localizado eliminan las partículas que pueden obturar los goteros. En la mayoría de los efluentes y filtrados fue mínimo el número de partículas con diámetros superiores a 20 μm. Sin embargo, al analizar la distribución del volumen de las partículas, en los filtrados aparecieron partículas de dimensiones superiores a la luz de los filtros de anillas y malla, siendo el filtro de arena el que retuvo las partículas de mayor diámetro. La eficiencia de los filtros para retener partículas se debió más al tipo de efluente que al filtro. Se verificó también que la distribución del número de partículas sigue una relación de tipo potencial. Analizando el exponente β de la ley potencial, se halló que los filtros no modificaron significativamente la distribución del número de partículas de los efluentes.

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In this work, a LIDAR-based 3D Dynamic Measurement System is presented and evaluated for the geometric characterization of tree crops. Using this measurement system, trees were scanned from two opposing sides to obtain two three-dimensional point clouds. After registration of the point clouds, a simple and easily obtainable parameter is the number of impacts received by the scanned vegetation. The work in this study is based on the hypothesis of the existence of a linear relationship between the number of impacts of the LIDAR sensor laser beam on the vegetation and the tree leaf area. Tests performed under laboratory conditions using an ornamental tree and, subsequently, in a pear tree orchard demonstrate the correct operation of the measurement system presented in this paper. The results from both the laboratory and field tests confirm the initial hypothesis and the 3D Dynamic Measurement System is validated in field operation. This opens the door to new lines of research centred on the geometric characterization of tree crops in the field of agriculture and, more specifically, in precision fruit growing.

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AimOur aim was to understand the interplay of heterogeneous climatic and spatial landscapes in shaping the distribution of nuclear microsatellite variation in burrowing parrots, Cyanoliseus patagonus. Given the marked phenotypic differences between populations of burrowing parrots we hypothesized an important role of geographical as well climatic heterogeneity in the population structure of this species. LocationSouthern South America. MethodsWe applied a landscape genetics approach to investigate the explicit patterns of genetic spatial autocorrelation based on both geography and climate using spatial principal component analysis (sPCA). This necessitated a novel statistical estimation of the species climatic landscape, considering temperature- and precipitation-based variables separately to evaluate their weight in shaping the distribution of genetic variation in our model system. ResultsGeographical and climatic heterogeneity successfully explained molecular variance in burrowing parrots. sPCA divided the species distribution into two main areas, Patagonia and the pre-Andes, which were connected by an area of geographical and climatic transition. Moreover, sPCA revealed cryptic and conservation-relevant genetic structure: the pre-Andean populations and the transition localities were each divided into two groups, each management units for conservation. Main conclusionssPCA, a method originally developed for spatial genetics, allowed us to unravel the genetic structure related to spatial and climatic landscapes and to visualize these patterns in landscape space. These novel climatic inferences underscore the importance of our modified sPCA approach in revealing how climatic variables can drive cryptic patterns of genetic structure, making the approach potentially useful in the study of any species distributed over a climatically heterogeneous landscape.

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Nowadays, one of the most important challenges to enhance the efficiency of thin film silicon solar cells is to increase the short circuit intensity by means of optical confinement methods, such as textured back-reflector structures. In this work, two possible textured structures to be used as back reflectors for n-i-p solar cells have been optically analyzed and compared to a smooth one by using a system which is able to measure the angular distribution function (ADF) of the scattered light in a wide spectral range (350-1000 nm). The accurate analysis of the ADF data corresponding to the reflector structures and to the μc-Si:H films deposited onto them allows the optical losses due to the reflector absorption and its effectiveness in increasing light absorption in the μc-Si:H layer, mainly at long wavelengths, to be quantified.

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Työn tärkeimpänä tavoitteena oli edistää ympäristöjärjestelmän laatimista Kvaerner Pulping, Power divisioonan Kattilat-liiketoimintayksikölle. Lisäksi tavoitteena oli tarkastella yritykseen kohdistuvia ympäristövaatimuksia ja niiden vaikutusta yrityksen toimintaan. Aluksi työssä tarkasteltiin ympäristöjärjestelmästandardien sisältöjä ja niiden eroja. Työssä käsiteltiin myös erilaisia elinkaarijohtamisen malleja, joita voidaan hyödyntää yrityksen kokonaisvaltaisessa ympäristöjärjestelmässä. Työssä tarkasteltiin myös sidosryhmien vaikutusta yrityksen ympäristötoimintaan. Kattilalaitostoimittajan tärkeimpiä asiakkaita ovat sellu- ja paperiteollisuus. Näihin yrityksiin on kohdistunut runsaan kymmenen vuoden aikana paineita ympäristötoiminnan tehostamiseksi. Tämän kehityksen seurauksena vastaavat tehostamispaineet ovat siirtymässä myös alihankkijoille, kuten kattilaitostoimittajille. Tehokkaan ympäristöjohtamisen takaamiseksi työssä määriteltiin ympäristövastuut ja –valtuudet sekä ympäristöpäämäärät ja –tavoitteet. Lisäksi tunnistettiin yrityksen toimintaan liittyvät ympäristönäkökohdat ja –riskit. Työn yhteydessä laadittiin ympäristöjärjestelmän luonnos, ja se sisältää jatkuvan parantamisen periaatteen. Työn yhteydessä laadittiin lisäksi Kvaerner Pulping Oy:n koelaitokselle ympäristölupahakemus. Työssä on kuvattu koelaitosta ja sen ympäristölupahakemukseen liittyviä asioita esimerkkinä parantuneesta ympäristöasioiden hoidosta.

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The microquasar LS 5039 has recently been detected as a source of very high energy (VHE) $\gamma$-rays. This detection, that confirms the previously proposed association of LS 5039 with the EGRET source 3EG~J1824$-$1514, makes of LS 5039 a special system with observational data covering nearly all the electromagnetic spectrum. In order to reproduce the observed spectrum of LS 5039, from radio to VHE $\gamma$-rays, we have applied a cold matter dominated jet model that takes into account accretion variability, the jet magnetic field, particle acceleration, adiabatic and radiative losses, microscopic energy conservation in the jet, and pair creation and absorption due to the external photon fields, as well as the emission from the first generation of secondaries. The radiative processes taken into account are synchrotron, relativistic Bremsstrahlung and inverse Compton (IC). The model is based on a scenario that has been characterized with recent observational results, concerning the orbital parameters, the orbital variability at X-rays and the nature of the compact object. The computed spectral energy distribution (SED) shows a good agreement with the available observational data.

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Maahantulostrategia asettaa yrityksen kansainvälisiä liiketoimintoja ohjaavat tavoitteet, päämäärät, resurssit ja toiminnan suuntaviivat. Tämä diplomityö käsittelee yrityksen maahantulostrategian elementeistä operaatiomuodon valintaa, hinnoittelua ja jakelua. Työssä rakennetaan teoriakehys elementteihin liittyvien päätösten tutkimiseksi lääketeollisuuden ominaispiirteet huomioiden. Lääketeollisuudella on muihin teollisuudenaloihin verrattuna useita erityispiirteitä, joihin työ perehdyttää. Lisäksi työn olennainen osa on selvittää lääketeollisuuden maakohtaisia säädöksiä ja toimintamalleja. Diplomityö on tehty silmäläkkeitä valmistavalle, kehittävälle ja markkinoivalle Santen Oy:lle, joka suunnittelee toimintansa laajentamista Keski- ja Etelä-Euroopan markkinoille. Tässä laajentumisprosessissa ensimmäisenä kohdemaana on Saksa, jonka markkinoille suuntautuvia toimenpiteitä työ tutkii. Teoriakehyksen, markkinoiden ominaispiirteiden sekä useiden erilaisten analyysien pohjalta työn tavoitteena on antaa operaatiomuotoa, tuotteiden hinnoittelua ja jakelua koskevia suosituksia.

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BACKGROUND/RATIONALE: Patient safety is a major concern in healthcare systems worldwide. Although most safety research has been conducted in the inpatient setting, evidence indicates that medical errors and adverse events are a threat to patients in the primary care setting as well. Since information about the frequency and outcomes of safety incidents in primary care is required, the goals of this study are to describe the type, frequency, seasonal and regional distribution of medication incidents in primary care in Switzerland and to elucidate possible risk factors for medication incidents. Label="METHODS AND ANALYSIS" ="METHODS"/> <AbstractText STUDY DESIGN AND SETTING: We will conduct a prospective surveillance study to identify cases of medication incidents among primary care patients in Switzerland over the course of the year 2015. PARTICIPANTS: Patients undergoing drug treatment by 167 general practitioners or paediatricians reporting to the Swiss Federal Sentinel Reporting System. INCLUSION CRITERIA: Any erroneous event, as defined by the physician, related to the medication process and interfering with normal treatment course. EXCLUSION CRITERIA: Lack of treatment effect, adverse drug reactions or drug-drug or drug-disease interactions without detectable treatment error. PRIMARY OUTCOME: Medication incidents. RISK FACTORS: Age, gender, polymedication, morbidity, care dependency, hospitalisation. STATISTICAL ANALYSIS: Descriptive statistics to assess type, frequency, seasonal and regional distribution of medication incidents and logistic regression to assess their association with potential risk factors. Estimated sample size: 500 medication incidents. LIMITATIONS: We will take into account under-reporting and selective reporting among others as potential sources of bias or imprecision when interpreting the results. ETHICS AND DISSEMINATION: No formal request was necessary because of fully anonymised data. The results will be published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT0229537.

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Päällystettyä paperia valmistettaessa syntyy päällystettyä hylkyä, joka kierrätetään takaisin prosessiin raaka-aineen tehokkaaksi hyödyntämiseksi. Hylyn mukana takaisin paperikoneen lyhyeen kiertoon päätyy myös pigmenttiaines levymäisinä partikkeleina. Nämä partikkelit rejektoituvat lyhyen kierron pyörrepuhdistimilla. Raaka-aineen hävikin pienentämiseksi käytetään lyhyessä kierrossa täyteaineen talteenottojärjestelmää, jonka tehtävänä on hienontaa päällystysainepartikkelit tasakokoisiksi, jotta ne voitaisiin palauttaa prosessiin. Talteenottolaitteistojen toiminnan tarkkailun kannalta on keskeistä tietää pyörrepuhdistuslaitoksen eri jakeiden partikkelikokojakaumat juuri pigmenttipartikkelien osalta. Tätä määritystä häiritsee näytteissä oleva kuitu. Tässä työssä pyrittiin löytämään partikkelikokoanalyysimenetelmä, jolla pigmenttien partikkelikokojakauma saataisiin selvitettyä kuidusta huolimatta. Aiemmin käytetty näytteen tuhkaus esikäsittelynä ennen partikkelikokoanalyysiä laserdiffraktiometrillä on osoittautunut toimimattomaksi. Kokeiden pääpaino keskittyi näytteen esikäsittelyyn fraktioinnilla ennen laserdiffraktioanalyysiä ja virtaussytometriamittauksiin. Fraktiointiin käytettiin DDJ-laitetta (dynamic drainage jar), joka oli varustettu metalliviiralla. Kumpikaan menetelmistä ei ollut täysin toimiva partikkelikokoanalyysiin, fraktioinnilla saadaan vähennettyä kuidun partikkelikokojakaumaan aiheuttamaa virhettä, mutta sen toimivuus riippuu paljolti näytteestä. Virtaussytometrialla väriainetta SYTO13 käyttämällä saadaan pigmenttipartikkelit tunnistettua ja näin rajattua kuidut pois mittauksista, mutta pigmenttiä ei saada erotettua puuperäisestä hienoaineesta, mikä vääristää mittaustulosta.