Kernel-based Mapping of Meteorological Fields in Complex Orography

Due to the advances in sensor networks and remote sensing technologies, the acquisition and storage rates of meteorological and climatological data increases every day and ask for novel and efficient processing algorithms. A fundamental problem of data analysis and modeling is the spatial prediction of meteorological variables in complex orography, which serves among others to extended climatological analyses, for the assimilation of data into numerical weather prediction models, for preparing inputs to hydrological models and for real time monitoring and short-term forecasting of weather.In this thesis, a new framework for spatial estimation is proposed by taking advantage of a class of algorithms emerging from the statistical learning theory. Nonparametric kernel-based methods for nonlinear data classification, regression and target detection, known as support vector machines (SVM), are adapted for mapping of meteorological variables in complex orography.With the advent of high resolution digital elevation models, the field of spatial prediction met new horizons. In fact, by exploiting image processing tools along with physical heuristics, an incredible number of terrain features which account for the topographic conditions at multiple spatial scales can be extracted. Such features are highly relevant for the mapping of meteorological variables because they control a considerable part of the spatial variability of meteorological fields in the complex Alpine orography. For instance, patterns of orographic rainfall, wind speed and cold air pools are known to be correlated with particular terrain forms, e.g. convex/concave surfaces and upwind sides of mountain slopes.Kernel-based methods are employed to learn the nonlinear statistical dependence which links the multidimensional space of geographical and topographic explanatory variables to the variable of interest, that is the wind speed as measured at the weather stations or the occurrence of orographic rainfall patterns as extracted from sequences of radar images. Compared to low dimensional models integrating only the geographical coordinates, the proposed framework opens a way to regionalize meteorological variables which are multidimensional in nature and rarely show spatial auto-correlation in the original space making the use of classical geostatistics tangled.The challenges which are explored during the thesis are manifolds. First, the complexity of models is optimized to impose appropriate smoothness properties and reduce the impact of noisy measurements. Secondly, a multiple kernel extension of SVM is considered to select the multiscale features which explain most of the spatial variability of wind speed. Then, SVM target detection methods are implemented to describe the orographic conditions which cause persistent and stationary rainfall patterns. Finally, the optimal splitting of the data is studied to estimate realistic performances and confidence intervals characterizing the uncertainty of predictions.The resulting maps of average wind speeds find applications within renewable resources assessment and opens a route to decrease the temporal scale of analysis to meet hydrological requirements. Furthermore, the maps depicting the susceptibility to orographic rainfall enhancement can be used to improve current radar-based quantitative precipitation estimation and forecasting systems and to generate stochastic ensembles of precipitation fields conditioned upon the orography.

Validity of the acoustic approximation in full-waveform seismic crosshole tomography

Acoustic waveform inversions are an increasingly popular tool for extracting subsurface information from seismic data. They are computationally much more efficient than elastic inversions. Naturally, an inherent disadvantage is that any elastic effects present in the recorded data are ignored in acoustic inversions. We investigate the extent to which elastic effects influence seismic crosshole data. Our numerical modeling studies reveal that in the presence of high contrast interfaces, at which P-to-S conversions occur, elastic effects can dominate the seismic sections, even for experiments involving pressure sources and pressure receivers. Comparisons of waveform inversion results using a purely acoustic algorithm on synthetic data that is either acoustic or elastic, show that subsurface models comprising small low-to-medium contrast (?30%) structures can be successfully resolved in the acoustic approximation. However, in the presence of extended high-contrast anomalous bodies, P-to-S-conversions may substantially degrade the quality of the tomographic images. In particular, extended low-velocity zones are difficult to image. Likewise, relatively small low-velocity features are unresolved, even when advanced a priori information is included. One option for mitigating elastic effects is data windowing, which suppresses later arriving seismic arrivals, such as shear waves. Our tests of this approach found it to be inappropriate because elastic effects are also included in earlier arriving wavetrains. Furthermore, data windowing removes later arriving P-wave phases that may provide critical constraints on the tomograms. Finally, we investigated the extent to which acoustic inversions of elastic data are useful for time-lapse analyses of high contrast engineered structures, for which accurate reconstruction of the subsurface structure is not as critical as imaging differential changes between sequential experiments. Based on a realistic scenario for monitoring a radioactive waste repository, we demonstrated that acoustic inversions of elastic data yield substantial distortions of the tomograms and also unreliable information on trends in the velocity changes.

Sectoral and occupational employment growth in Spain 1995-2005

Between 1995 and 2005, the Spanish economy grew at an annual average rate higher than 3,5%. Total employment increased by more than 4.9 millions. Most of this growth was in occupations related with university degrees (more than 890,000, 18% of the total employment increase) and vocational qualifications (more than 855,000, 17.5% of the total employment increase). From a sectoral perspective, the main part of this increase took place in “Real estate, renting and business activities” (K sector in NACE rev.1), “Construction” (F sector) and “Health and social sector” (N sector). This paper analyses this employment growth in an Input-output framework, by means of a structural decomposition analysis (SDA). Two kinds of results have been obtained. From a sectoral perspective we decompose employment growth into Labour requirements change, technical change and demand change. From an occupational perspective, we decompose the employment growth in substitutions effect, labour productivity effect and demand effect. The results show that, in aggregated terms, the main part of this growth is attributable to demand growth, with a small technical improvement. But the results also show that this aggregated behaviour hides important sectoral and occupational variation. The purpose of this paper is to contribute to the ongoing debate over productivity growth and what has been called the “growth model” for the Spanish economy.

Software for interpolation of vegetative growth of yerba mate plants in 3D

The objective of this work was to build mock-ups of complete yerba mate plants in several stages of development, using the InterpolMate software, and to compute photosynthesis on the interpolated structure. The mock-ups of yerba-mate were first built in the VPlants software for three growth stages. Male and female plants grown in two contrasting environments (monoculture and forest understory) were considered. To model the dynamic 3D architecture of yerba-mate plants during the biennial growth interval between two subsequent prunings, data sets of branch development collected in 38 dates were used. The estimated values obtained from the mock-ups, including leaf photosynthesis and sexual dimorphism, are very close to those observed in the field. However, this similarity was limited to reconstructions that included growth units from original data sets. The modeling of growth dynamics enables the estimation of photosynthesis for the entire yerba mate plant, which is not easily measurable in the field. The InterpolMate software is efficient for building yerba mate mock-ups.

Verkkonaapuruston valvontatehtävien siirto mobiililaitteelta kiinteälle laitteelle PeerHood -verkossa

PeerHood -verkon mobiililaitteiden akkutehon säästämiseksi siirretään mobiililaitteen verkkonaapuruston valvontatehtävät kiinteälle laitteelle. Valvontatehtävien siirto on tarkoitus tehdä silloin, kun laite pysyy paikallaan, esimerkiksi toimisto tiloissa. Laitteen pysyessä paikallaan voidaan verkkonaapurustoa seurata kiinteän laitteen resursseilla ja päivittää verkkomuutokset mobiililaitteelle tarvittaessa. Mobiililaitteen ollessa vain kuuntelutilassa laite säästää akkutehoa, koska sen ei tarvitse aktiivisesti lähettää dataa verkkolaitteillaan. Verkkolaitteet pysyvät lepotilassa ja odottavat vain tulevaa dataa. Verkkonaapuruston valvontatehtävien siirto ei kuitenkaan vaikuta käyttäjän palveluiden hyödyntämiseen, joten verkkolaitteen akkutehon säästö riippuu suuresti käyttäjän toimista, käyttäjä voi edelleen käyttää muiden PeerHood laitteiden palveluita tai tarjota omiaan.

Migració a programari lliure de la infraestructura de servidors de CETRAMSA

Aquest projecte s'emmarca dins el màster en Programari lliure de la UOC, en l'especialitat de xarxes i sistemes operatius. En ell he col·laborat amb CETRAMSA, empresa dedicada a la informació i difusió al ciutadà de l'oferta de transport públic en l'àmbit metropolità de Barcelona, per dur a terme la migració de la seva infraestructura de servidors a programari lliure.

Six Sigman soveltamisedellytysten ja -apuvälineiden luominen

Diplomityön tavoitteena oli luoda soveltamisedellytyksiä ja -apuvälineitä Six Sigma -parannusprojektien läpiviennille Perlos Oyj Connectorsin meistoprosessissa. Työn teoriaosassa käsitellään Six Sigman perusteoriaa, organisointia ja soveltamista sekä suorituskykymittariston ja tiedonkeruumenetelmien luomista. Kirjallisuuden tarjoaman teorian jälkeen työssä tutustuttiin meistoprosessiin ja Perloksen tapaan soveltaa Six Sigmaa prosessien parantamiseen. Tämän perusteella kehitettiin tiedonkeruu-, dokumentointi- ynnä muita apuvälineitä parantamisprojektien tueksi. Lopuksi koekäytettiin luotuja välineitä meistoon tehdyn osittaisen Six Sigma -projektin yhteydessä. Luotettavan tiedon saaminen prosesseista on perusedellytys Six Sigma -projektien läpiviennille. Menetelmän kouluttaminen työntekijöille on myös tärkeää. Erilaiset dokumentointi- ja laskentakaavakkeet toimivat projektien läpiviennin ja seurannan tukena. Työssä luotuja tiedonkeruu-, koulutus-, dokumentointi- ynnä muita apuvälineitä voidaan käyttää jatkossa apuna Perloksella tehtävissä Six Sigma -projekteissa. Mittaristoa ja tiedonkeruuta tulee kehittää edelleen, jotta prosessien toimintaa voidaan analysoida tehokkaasti. Työn lopussa on ajatuksia Six Sigman käytöstä sekä tiedonkeruujärjestelmien jatkokehityksestä.

Anonymizing Graphs: Measuring Quality for Clustering

Peer-reviewed

Murros projektikohtaisista ratkaisuista tuotteiden systemaattiseen kehittämiseen ja hallintaan

Tämä tutkimus käsittelee strategiamuutoksen toimeenpanoa projektiliiketoimintaympäristössä toimivan liiketoimintayksikön tuotekehitys-, suunnittelu- ja tuotetoimitusprosesseissa. Muutoksen tavoitteena on tuoterakenteiden ja toimitusprosessien hallinta pelkän resurssien hallinnan sijaan. Työn tavoitteena on kuvaus siitä, mitä muutoksia strategisten tavoitteiden saavuttaminen edellyttää liiketoimintayksikön tuoteprosessien, tuotearkkitehtuurin ja tietojärjestelmien osalta. Tutkimuksen teoriaosuus käsittelee teknologiastrategiaa, tuotetiedon hallintaa, tuotearkkitehtuureja sekä tuotekehitystoiminnan prosesseja ja menestystekijöitä. Tutkimuksen empiriaosuudessa peilataan liiketoimintayksikön nykytilaa ja strategisia tavoitteita esitettyyn teoreettiseen viitekehykseen, sekä suoritetaan analyysi tavoitellun muutoksen edellytyksistä. Työn tulos sisältää sarjan toimenpiteitä ja näistä muodostetun käsitekartan, joka kuvaa muutosprosessia kokonaisuutena: tuoterakenteiden, tuotetiedon hallinnan, prosessien ja organisaatioiden osalta.

Inmigración, crisis económica y discursos radiofónicos: hacia un lenguaje excluyente

Los medios de comunicación juegan un rol fundamental en la percepción social del proceso migratorio y de las minorías étnicas. A través del análisis de un conjunto de emisiones de Catalunya Radio, RAC1 y la COPE, el estudio que presentamos pretende determinar si el discurso radiofónico se fundamenta en un lenguaje inclusivo que contribuye a la cohesión social, o bien promueve un sobredimensionamiento de los conflictos contribuyendo a extender la xenofobia. Coincidiendo con la crisis, el lenguaje excluyente se consolida y se extiende en los medios. El análisis desarrollado evidencia el uso de conceptos y estrategias discursivas que remiten, por una parte, al racismo moderno y, por otra, al lenguaje del odio, siendo frecuentes las imprecisiones, la invisibilidad u homogeneización de determinados colectivos, la contraposición nosotrosellos o enfoques basados en el conflicto que enfatizan las diferencias étnicas.

Separation of Gas Bubbles from Circulation Waters and Pulp Suspensions in Open Channel Flow

The objective of this thesis was to study the removal of gases from paper mill circulation waters experimentally and to provide data for CFD modeling. Flow and bubble size measurements were carried out in a laboratory scale open gas separation channel. Particle Image Velocimetry (PIV) technique was used to measure the gas and liquid flow fields, while bubble size measurements were conducted using digital imaging technique with back light illumination. Samples of paper machine waters as well as a model solution were used for the experiments. The PIV results show that the gas bubbles near the feed position have the tendency to escape from the circulation channel at a faster rate than those bubbles which are further away from the feed position. This was due to an increased rate of bubble coalescence as a result of the relatively larger bubbles near the feed position. Moreover, a close similarity between the measured slip velocities of the paper mill waters and that of literature values was obtained. It was found that due to dilution of paper mill waters, the observed average bubble size was considerably large as compared to the average bubble sizes in real industrial pulp suspension and circulation waters. Among the studied solutions, the model solution has the highest average drag coefficient value due to its relatively high viscosity. The results were compared to a 2D steady sate CFD simulation model. A standard Euler-Euler k-ε turbulence model was used in the simulations. The channel free surface was modeled as a degassing boundary. From the drag models used in the simulations, the Grace drag model gave velocity fields closest to the experimental values. In general, the results obtained from experiments and CFD simulations are in good qualitative agreement.

Toiminnanohjausjärjestelmän käyttöönoton onnistuminen ja siihen vaikuttavat tekijät Pyrollsack Oy:ssä

Tämä diplomityö käsittelee toiminnanohjausjärjestelmän käyttöönottoa ja käyttöönoton kriittisten menestystekijöiden toteutumista. Työn tavoitteena oli tutkia kirjallisuudessa esiintyviä käyttöönoton kriittisiä menestystekijöitä ja verrata niitä Pyrollsack Oy:n käyttöönottoprosessista saatuihin kokemuksiin. Tuloksena voidaan havaita menestystekijät sekä esittää parannusehdotuksia havaittuihin heikkouksiin. Käyttöönottoprojektissa vahvuuksina nähtiin huolellinen valmistautuminen projektiin, uuden toiminnanohjausjärjestelmän strategisen merkityksen ymmärtäminen, nopea päätöksenteko sekä operatiivisen käyttöönoton ajoitus ja vaiheistus. Heikkouksina nähtiin liiallinen viive suunnittelun ja toteutuksen välillä, riittämättömät henkilöresurssit, ohjausryhmän toimimattomuus, viestintä, muutosjohtaminen, puutteellinen tietojen konversio, koulutus sekä toimittajan puutteellinen ymmärrys tehdystä vaatimusmäärittelystä. Käyttöönotto tulisi nähdä laajana projektina, joka koskee koko organisaatiota. Pienissä ja keskisuurissa yrityksissä erityistä huomiota tulee kiinnittää henkilöresurssien riittävyyteen. Uusi toiminnanohjausjärjestelmä saattaa aiheuttaa hetkellisen taantuman toiminnan sujuvuudessa. Toiminnanohjausjärjestelmän hyödyt toiminnalle ovat vaikeasti mitattavissa ja usein positiiviset vaikutukset havaitaan vasta vuosien päästä.

Thinking Outside the Box: Enhancing Science Teaching by Combining (Instead of Contrasting) Laboratory and Simulation Activities

The focus of the present work was on 10- to 12-year-old elementary school students’ conceptual learning outcomes in science in two specific inquiry-learning environments, laboratory and simulation. The main aim was to examine if it would be more beneficial to combine than contrast simulation and laboratory activities in science teaching. It was argued that the status quo where laboratories and simulations are seen as alternative or competing methods in science teaching is hardly an optimal solution to promote students’ learning and understanding in various science domains. It was hypothesized that it would make more sense and be more productive to combine laboratories and simulations. Several explanations and examples were provided to back up the hypothesis. In order to test whether learning with the combination of laboratory and simulation activities can result in better conceptual understanding in science than learning with laboratory or simulation activities alone, two experiments were conducted in the domain of electricity. In these experiments students constructed and studied electrical circuits in three different learning environments: laboratory (real circuits), simulation (virtual circuits), and simulation-laboratory combination (real and virtual circuits were used simultaneously). In order to measure and compare how these environments affected students’ conceptual understanding of circuits, a subject knowledge assessment questionnaire was administered before and after the experimentation. The results of the experiments were presented in four empirical studies. Three of the studies focused on learning outcomes between the conditions and one on learning processes. Study I analyzed learning outcomes from experiment I. The aim of the study was to investigate if it would be more beneficial to combine simulation and laboratory activities than to use them separately in teaching the concepts of simple electricity. Matched-trios were created based on the pre-test results of 66 elementary school students and divided randomly into a laboratory (real circuits), simulation (virtual circuits) and simulation-laboratory combination (real and virtual circuits simultaneously) conditions. In each condition students had 90 minutes to construct and study various circuits. The results showed that studying electrical circuits in the simulation–laboratory combination environment improved students’ conceptual understanding more than studying circuits in simulation and laboratory environments alone. Although there were no statistical differences between simulation and laboratory environments, the learning effect was more pronounced in the simulation condition where the students made clear progress during the intervention, whereas in the laboratory condition students’ conceptual understanding remained at an elementary level after the intervention. Study II analyzed learning outcomes from experiment II. The aim of the study was to investigate if and how learning outcomes in simulation and simulation-laboratory combination environments are mediated by implicit (only procedural guidance) and explicit (more structure and guidance for the discovery process) instruction in the context of simple DC circuits. Matched-quartets were created based on the pre-test results of 50 elementary school students and divided randomly into a simulation implicit (SI), simulation explicit (SE), combination implicit (CI) and combination explicit (CE) conditions. The results showed that when the students were working with the simulation alone, they were able to gain significantly greater amount of subject knowledge when they received metacognitive support (explicit instruction; SE) for the discovery process than when they received only procedural guidance (implicit instruction: SI). However, this additional scaffolding was not enough to reach the level of the students in the combination environment (CI and CE). A surprising finding in Study II was that instructional support had a different effect in the combination environment than in the simulation environment. In the combination environment explicit instruction (CE) did not seem to elicit much additional gain for students’ understanding of electric circuits compared to implicit instruction (CI). Instead, explicit instruction slowed down the inquiry process substantially in the combination environment. Study III analyzed from video data learning processes of those 50 students that participated in experiment II (cf. Study II above). The focus was on three specific learning processes: cognitive conflicts, self-explanations, and analogical encodings. The aim of the study was to find out possible explanations for the success of the combination condition in Experiments I and II. The video data provided clear evidence about the benefits of studying with the real and virtual circuits simultaneously (the combination conditions). Mostly the representations complemented each other, that is, one representation helped students to interpret and understand the outcomes they received from the other representation. However, there were also instances in which analogical encoding took place, that is, situations in which the slightly discrepant results between the representations ‘forced’ students to focus on those features that could be generalised across the two representations. No statistical differences were found in the amount of experienced cognitive conflicts and self-explanations between simulation and combination conditions, though in self-explanations there was a nascent trend in favour of the combination. There was also a clear tendency suggesting that explicit guidance increased the amount of self-explanations. Overall, the amount of cognitive conflicts and self-explanations was very low. The aim of the Study IV was twofold: the main aim was to provide an aggregated overview of the learning outcomes of experiments I and II; the secondary aim was to explore the relationship between the learning environments and students’ prior domain knowledge (low and high) in the experiments. Aggregated results of experiments I & II showed that on average, 91% of the students in the combination environment scored above the average of the laboratory environment, and 76% of them scored also above the average of the simulation environment. Seventy percent of the students in the simulation environment scored above the average of the laboratory environment. The results further showed that overall students seemed to benefit from combining simulations and laboratories regardless of their level of prior knowledge, that is, students with either low or high prior knowledge who studied circuits in the combination environment outperformed their counterparts who studied in the laboratory or simulation environment alone. The effect seemed to be slightly bigger among the students with low prior knowledge. However, more detailed inspection of the results showed that there were considerable differences between the experiments regarding how students with low and high prior knowledge benefitted from the combination: in Experiment I, especially students with low prior knowledge benefitted from the combination as compared to those students that used only the simulation, whereas in Experiment II, only students with high prior knowledge seemed to benefit from the combination relative to the simulation group. Regarding the differences between simulation and laboratory groups, the benefits of using a simulation seemed to be slightly higher among students with high prior knowledge. The results of the four empirical studies support the hypothesis concerning the benefits of using simulation along with laboratory activities to promote students’ conceptual understanding of electricity. It can be concluded that when teaching students about electricity, the students can gain better understanding when they have an opportunity to use the simulation and the real circuits in parallel than if they have only the real circuits or only a computer simulation available, even when the use of the simulation is supported with the explicit instruction. The outcomes of the empirical studies can be considered as the first unambiguous evidence on the (additional) benefits of combining laboratory and simulation activities in science education as compared to learning with laboratories and simulations alone.

Tiedonhallinnan kehittäminen prosessikuvausten ja sähköisen dokumentoinnin avulla

Tämän diplomityön tavoitteena on selkeyttää apteekin ydinprosesseja mallintamalla prosessit ja tehostaa apteekin tiedonhallintaa sähköisen toimintajärjestelmän avulla. Ydinprosessien mallintaminen lisää apteekin työntekijöiden tietoisuutta prosessien oikeasta suoritustavasta. Dokumenttien sijoittaminen yhteen paikkaan helpottaa niiden löytymistä ja käytettävyyttä. Tässä työssä tutkittiin yhtä yritystä, joten tutkimusmenetelmänä käytettiin tapaustutkimusta. Työn keskeinen sisältö rakentuu tiedonhallinnan, prosessijohtamisen sekä sähköisen toimintajärjestelmän teorioiden pohjalta. Teoriaa hyödynnetään käytännön tutkimuksessa, jossa kartoitetaan apteekin dokumentit ja kehitetään niiden organisointia. Työssä tunnistetaan ja mallinnetaan apteekin ydinprosessit sekä kerätään tietoa niiden ongelmakohdista. Apteekin ydinprosesseiksi tunnistettiin reseptiasiakkaan palvelu ja neuvonta, itsehoitoasiakkaan palvelu ja neuvonta, kotisairaanhoidon ja hoivakotien palvelu sekä tavaranhallinta. Apteekissa luodut dokumentit luokiteltiin toimintaohjeiksi, työohjeiksi, lomakkeiksi ja rekisteriselosteiksi. Työn tuloksena apteekin tiedonhallinta tehostui dokumenttien sähköistämisellä ja organisoinnilla toimintajärjestelmään. Ydinprosessien mallintaminen selkeytti apteekin ydinprosesseja sekä lisäsi työntekijöiden tietoisuutta prosessien oikeasta toimintatavasta.

Fedora Commons as core repository of the EU legislation

Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014