12 resultados para anomalous Eu3 5D0->F-7(0) transition

em Doria (National Library of Finland DSpace Services) - National Library of Finland, Finland


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Doctoral dissertation, Academy of Fine Arts

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TyÃn tarkoituksena on tutkia pinon ylikirjoitukseen perustuvien hyÃkkäysten toimintaa ja osoittaa kokeellisesti nykyisten suojaustekniikoiden olevan riittämättÃmiä. Tutkimus suoritetaan testaamalla miten valitut tietoturvatuotteet toimivat eri testitilanteissa. Testatut tuotteet ovat Openwall, PaX, Libsafe 2.0 ja Immunix 6.2. Testaus suoritetaan pääasiassa RedHat 7.0 ympäristÃssä testiohjelman avulla. Testeissä mitataan sekä tuotteiden kyky havaita hyÃkkäyksiä että niiden nopeusvaikutukset. MyÃs erityyppisten hyÃkkäysten ja niitä vastaan kehitettyjen metodien toimintaperiaatteet esitellään seikkaperäisesti ja havainnollistetaan yksinkertaistetuilla esimerkeillä. Esitellyt tekniikat sisältävät puskurin ylivuodot, laittomat muotoiluparametrit, loppumerkittÃmät merkkijonot ja taulukoiden ylivuodot. Testit osoittavat, etteivät valitut tuotteet estä kaikkia hyÃkkäyksiä, joten lopuksi perehdytään myÃs vahinkojen minimointiin onnistuneiden hyÃkkäysten varalta.

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Dedicatio: Jacob Sporman [ruots. pr.], Anna Sporman s. Schulin [ruots. pr.].

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Tässä diplomityÃssä on määritetty paluuvesilämmityksen mahdollisuudet Savon Voima Oyj:n kaukolämpÃpaikkakunnilla. TyÃssä tarkasteltiin paluuvesilämmityksen tuoman paremman kaukolämpÃveden jäähtymän vaikutuksia kaukolämpÃverkkoon ja energiantuotantoon sekä laskettiin esimerkkipaikkakunnilla kaukolämmÃn paluuveden lämpÃtilan alentumisen tuomat rahalliset hyÃdyt. Lisäksi tarkasteltiin paluuvesilämmityksen taloudellisuutta esimerkkipaikkakunnilla. Laskennassa saatiin paluuvesilämmityksen tuomaksi jäähtymähyÃdyksi pumppauskustannuksissa 0,7 â 0,8 â¬/MWh ja lämpÃhäviÃissä 1,5 â 2,9 â¬/MWh. Iisalmessa sähkÃntuotannon lisääntymisestä saadaan hyÃtyä 0,7 â¬/MWh. Suurin hyÃty saadaan Pielaveden ja Suonenjoen biolämpÃkeskusten lämmÃntalteenotolla varustetuista savukaasupesureista. Pielavedellä tämä hyÃty on 6,4 â¬/MWh ja Suonenjoella 6,1 â¬/MWh. Paluuvesilämmityksen kannattavuus asuinkiinteistÃissä vaatii lämmÃntuotannon yhteydessä olevan savukaasupesurin tuoman rahallisen hyÃdyn. Esimerkiksi Iisalmessa asiakkaalle myÃnnettävissä oleva jäähtymähyvitys paluuvesilämmÃstä ei riitä kattamaan paluuvesilämmityksen suurempia investointikuluja. MyÃs pesuripaikkakunnilla kannattavuus vaatii suuren vuosittaisen lämmÃnkäytÃn. Tavoiteltaessa 8 vuoden korollista takaisinmaksuaikaa vaatii kannattavuus kohteelta Pielavedellä 250 MWh:n ja Suonejoella 300 MWh:n vuosittaisen lämmÃnkäytÃn. MyÃs asiakkaan sijainnin sopivuus kaukolämpÃverkossa paluuvesilämmitykseen täytyy tarkastella tapauskohtaisesti. Paluuvesilämmitys ei tule tyÃn tulosten perusteella tulevaisuudessa yleisesti käyttÃÃn, mutta yksittäisiä asiakkaita siihen voidaan liittää.

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Tutkimuksessa on tutkittu julkisiin lähteisiin perustuen venäläisten ilmasta laukaistavien kaukovaikutteisten aseiden nykytilaa ja kehitysnäkymiä. Tutkimuksessa on selvitetty ohjuksissa käytettyjä teknisiä ratkaisuja sekä niiden vaikutusta ohjusten suorituskykyyn. Ohjukset ja niiden tulevaisuuden näkymät on käyty läpi osa-alueittain; ominaisuudet, voimalaite, taistelulataus, sekä suunnistus- ja hakeutumisjärjestelmät. Tutkimuksessa on käsitelty myÃs aselavetteja jotka kykenevät laukaisemaan kauaskantoisia ilmasta maahan ja ilmasta merelle ohjuksia. Tutkimuksessa on käsitelty myÃs ohjusten ja lavettien tulevaisuuden näkymiä. Lavettien kehitysnäkymät on käyty läpi konekalustoittain yleisellä tasolla. Venäläiset asevalmistajat kehittävät aktiivisesti ilmasta laukaistavia kauaskantoisia aseita. Strategisia ohjuksia on suunniteltu ja valmistettu omaan käyttÃÃn. Taktisen tasan ohjuksia on valmistettu enemmän vientimarkkinoille. Uudemmissa venäläisvalmisteisissa ohjuksissa on ja tulee jatkossa olemaan myÃs kehittyneemmät, tarkemmat ja paremmin häirintää sietävät hakeutumisjärjestelmät. Tulevaisuuden näkymistä merkille pantavin on ohjuksen nopeuden kasvattaminen. Venäjän ja Intian yhteistyÃnä kehittämä Brahmos kykenee lentämään lähes 3.0 Machin nopeudella. Tällä hetkellä on kehitystyà käynnissä myÃs hypersoonisen ohjuksen kehittämiseksi. 5.0-7.0 Machin nopeudella lentävän ohjuksen kehitystyà on kuitenkin haasteellista.

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Kainuun ELY-keskus ja TE-toimisto kartoittivat syksyn 2013 aikana matkailualan yritysten tyÃvoima-, koulutus- ja muita kehittämistarpeita sekä alan kehitysnäkymiä. Yrityskäynneillä haastateltiin sekä majoitus- ja ravitsemistoiminnan että matkailun ohjelmapalveluiden yrityksiä. Haastatellut 43 yritystä tyÃllistivät haastatteluhetkellä yhteensä 499 henkilÃä. Matkailualan lähiajan kehitysnäkymät Kainuussa näyttävät suotuisilta. Yritykset arvioivat alan suhdannetilanteen kehittyvän hyvään suuntaan. Yrityksillä on myÃs runsaasti erilaisia investointisuunnitelmia tuleville vuosille. Suunnitelmissa on sekä majoituskapasiteetin lisäystä että muuta uudisrakentamista, remontointia ja laitehankintoja. Kapasiteetin kasvaessa yrityksillä on tarvetta ja halua rekrytoida lisää tyÃntekijÃitä. Seuraavan vuoden aikana henkilÃstÃmäärän haastatelluissa yrityksissä arvioitiin kasvavan yhteensä 35 hengellä (7,0 %). Matkailualan yrityksillä verkostomainen toiminta on arkipäivää. Yhteismarkkinointi on esimerkiksi hyvä keino saada pientenkin yritysten tarjoamia tuotteita ja palveluja esille. Yritykset kaipasivat kuitenkin lisää ohjelmapalveluja ja etenkin koottuja ohjelmapaketteja majoituspalvelujen tueksi. Alalla on kysyntää myÃs monenlaisille muillekin palveluille, joita ei kannata hoitaa omana toimintana, kuten kiinteistÃhuolto- ja cateringpalveluille. SähkÃisen liiketoiminnan kehittyminen on muuttanut matkailupalvelujen myyntiä, joka tapahtuu entistä enemmän suoraan netissä eikä matkatoimistojen palveluja tarvita entiseen tapaan. Verkkoliiketoiminnan keinoja hyÃdynnetään jo laajasti, mutta osa haastatelluista yrityksistä ilmoitti tarvitsevansa tukea esimerkiksi varausjärjestelmien käyttÃÃnotossa. Monilla haastatelluista yrityksistä huomattava osa asiakkaista on ulkomaalaisia. Ulkomaisten asiakkaiden määrän uskotaan myÃs kasvavan. Yleisin ulkomaalaisten asiakkaiden ryhmä ovat venäläiset. Ulkomaiset asiakkaat on jo otettu huomioon palveluiden markkinoinnissa. Yrityksissä on kuitenkin tarvetta parantaa asiakaspalvelutehtävissä toimivan henkilÃstÃn venäjän ja englannin kielten taitoa sekä lisätä muuta kansainvälistymiseen liittyvää osaamista.

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Tietokoneohjelman arvostelu.

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The aim of the present set of longitudinal studies was to explore 3-7-year-old children.s Spontaneous FOcusing on Numerosity (SFON) and its relation to early mathematical development. The specific goals were to capture in method and theory the distinct process by which children focus on numerosity as a part of their activities involving exact number recognition, and individual differences in this process that may be informative in the development of more complex number skills. Over the course of conducting the five studies, fifteen novel tasks were progressively developed for the SFON assessments. In the tasks, confounding effects of insufficient number recognition, verbal comprehension, other procedural skills as well as working memory capacity were aimed to be controlled. Furthermore, how children.s individual differences in SFON are related to their development of number sequence, subitizing-based enumeration, object counting and basic arithmetic skills was explored. The effect of social interaction on SFON was tested. Study I captured the first phase of the 3-year longitudinal study with 39 children. It was investigated whether there were differences in 3-year-old children.s tendency to focus on numerosity, and whether these differences were related to the children.s development of cardinality recognition skills from the age of 3 to 4 years. It was found that the two groups of children formed on the basis of their amount of SFON tendency at the age of 3 years differed in their development of recognising and producing small numbers. The children whose SFON tendency was very predominant developed faster in cardinality related skills from the age of 3 to 4 years than the children whose SFON tendency was not as predominant. Thus, children.s development in cardinality recognition skills is related to their SFON tendency. Studies II and III were conducted to investigate, firstly, children.s individual differences in SFON, and, secondly, whether children.s SFON is related to their counting development. Altogether nine tasks were designed for the assessments of spontaneous and guided focusing on numerosity. The longitudinal data of 39 children in Study II from the age of 3.5 to 6 years showed individual differences in SFON at the ages of 4, 5 and 6 years, as well as stability in children.s SFON across tasks used at different ages. The counting skills were assessed at the ages of 3.5, 5 and 6 years. Path analyses indicated a reciprocal tendency in the relationship between SFON and counting development. In Study III, these results on the individual differences in SFON tendency, the stability of SFON across different tasks and the relationship of SFON and mathematical skills were confirmed by a larger-scale cross-sectional study of 183 on average 6.5-year-old children (range 6;0-7;0 years). The significant amount of unique variance that SFON accounted for number sequence elaboration, object counting and basic arithmetic skills stayed statistically significant (partial correlations varying from .27 to .37) when the effects of non-verbal IQ and verbal comprehension were controlled. In addition, to confirm that the SFON tasks assess SFON tendency independently from enumeration skills, guided focusing tasks were used for children who had failed in SFON tasks. It was explored whether these children were able to proceed in similar tasks to SFON tasks once they were guided to focus on number. The results showed that these children.s poor performance in the SFON tasks was not caused by their deficiency in executing the tasks but on lacking focusing on numerosity. The longitudinal Study IV of 39 children aimed at increasing the knowledge of associations between children.s long-term SFON tendency, subitizing-based enumeration and verbal counting skills. Children were tested twice at the age of 4-5 years on their SFON, and once at the age of 5 on their subitizing-based enumeration, number sequence production, as well as on their skills for counting of objects. Results showed considerable stability in SFON tendency measured at different ages, and that there is a positive direct association between SFON and number sequence production. The association between SFON and object counting skills was significantly mediated by subitizing-based enumeration. These results indicate that the associations between the child.s SFON and sub-skills of verbal counting may differ on the basis of how significant a role understanding the cardinal meanings of number words plays in learning these skills. The specific goal of Study V was to investigate whether it is possible to enhance 3-year old children.s SFON tendency, and thus start children.s deliberate practice in early mathematical skills. Participants were 3-year-old children in Finnish day care. The SFON scores and cardinality-related skills of the experimental group of 17 children were compared to the corresponding results of the 17 children in the control group. The results show an experimental effect on SFON tendency and subsequent development in cardinality-related skills during the 6-month period from pretest to delayed posttest in the children with some initial SFON tendency in the experimental group. Social interaction has an effect on children.s SFON tendency. The results of the five studies assert that within a child.s existing mathematical competence, it is possible to distinguish a separate process, which refers to the child.s tendency to spontaneously focus on numerosity. Moreover, there are significant individual differences in children.s SFON at the age of 3-7 years. Moderate stability was found in this tendency across different tasks assessed both at the same and at different ages. Furthermore, SFON tendency is related to the development of early mathematical skills. Educational implications of the findings emphasise, first, the importance of regarding focusing on numerosity as a separate, essential process in the assessments of young children.s mathematical skills. Second, the substantial individual differences in SFON tendency during the childhood years suggest that uncovering and modeling this kind of mathematically meaningful perceiving of the surroundings and tasks could be an efficient tool for promoting young children.s mathematical development, and thus prevent later failures in learning mathematical skills. It is proposed to consider focusing on numerosity as one potential sub-process of activities involving exact number recognition in future studies.

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In this thesis, stepwise titration with hydrochloric acid was used to obtain chemical reactivities and dissolution rates of ground limestones and dolostones of varying geological backgrounds (sedimentary, metamorphic or magmatic). Two different ways of conducting the calculations were used: 1) a first order mathematical model was used to calculate extrapolated initial reactivities (and dissolution rates) at pH 4, and 2) a second order mathematical model was used to acquire integrated mean specific chemical reaction constants (and dissolution rates) at pH 5. The calculations of the reactivities and dissolution rates were based on rate of change of pH and particle size distributions of the sample powders obtained by laser diffraction. The initial dissolution rates at pH 4 were repeatedly higher than previously reported literature values, whereas the dissolution rates at pH 5 were consistent with former observations. Reactivities and dissolution rates varied substantially for dolostones, whereas for limestones and calcareous rocks, the variation can be primarily explained by relatively large sample standard deviations. A list of the dolostone samples in a decreasing order of initial reactivity at pH 4 is: 1) metamorphic dolostones with calcite/dolomite ratio higher than about 6% 2) sedimentary dolostones without calcite 3) metamorphic dolostones with calcite/dolomite ratio lower than about 6% The reactivities and dissolution rates were accompanied by a wide range of experimental techniques to characterise the samples, to reveal how different rocks changed during the dissolution process, and to find out which factors had an influence on their chemical reactivities. An emphasis was put on chemical and morphological changes taking place at the surfaces of the particles via X-ray Photoelectron Spectroscopy (XPS) and Scanning Electron Microscopy (SEM). Supporting chemical information was obtained with X-Ray Fluorescence (XRF) measurements of the samples, and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) measurements of the solutions used in the reactivity experiments. Information on mineral (modal) compositions and their occurrence was provided by X-Ray Diffraction (XRD), Energy Dispersive X-ray analysis (EDX) and studying thin sections with a petrographic microscope. BET (Brunauer, Emmet, Teller) surface areas were determined from nitrogen physisorption data. Factors increasing chemical reactivity of dolostones and calcareous rocks were found to be sedimentary origin, higher calcite concentration and smaller quartz concentration. Also, it is assumed that finer grain size and larger BET surface areas increase the reactivity although no certain correlation was found in this thesis. Atomic concentrations did not correlate with the reactivities. Sedimentary dolostones, unlike metamorphic ones, were found to have porous surface structures after dissolution. In addition, conventional (XPS) and synchrotron based (HRXPS) X-ray Photoelectron Spectroscopy were used to study bonding environments on calcite and dolomite surfaces. Both samples are insulators, which is why neutralisation measures such as electron flood gun and a conductive mask were used. Surface core level shifts of 0.7 ± 0.1 eV for Ca 2p spectrum of calcite and 0.75 ± 0.05 eV for Mg 2p and Ca 3s spectra of dolomite were obtained. Some satellite features of Ca 2p, C 1s and O 1s spectra have been suggested to be bulk plasmons. The origin of carbide bonds was suggested to be beam assisted interaction with hydrocarbons found on the surface. The results presented in this thesis are of particular importance for choosing raw materials for wet Flue Gas Desulphurisation (FGD) and construction industry. Wet FGD benefits from high reactivity, whereas construction industry can take advantage of slow reactivity of carbonate rocks often used in the facades of fine buildings. Information on chemical bonding environments may help to create more accurate models for water-rock interactions of carbonates.

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Solvent extraction of calcium and magnesium impurities from a lithium-rich brine (Ca ~ 2,000 ppm, Mg ~ 50 ppm, Li ~ 30,000 ppm) was investigated using a continuous counter-current solvent extraction mixer-settler set-up. The literature review includes a general review about resources, demands and production methods of Li followed by basics of solvent extraction. Experimental section includes batch experiments for investigation of pH isotherms of three extractants; D2EHPA, Versatic 10 and LIX 984 with concentrations of 0.52, 0.53 and 0.50 M in kerosene respectively. Based on pH isotherms LIX 984 showed no affinity for solvent extraction of Mg and Ca at pH ⤠8 while D2EHPA and Versatic 10 were effective in extraction of Ca and Mg. Based on constructed pH isotherms, loading isotherms of D2EHPA (at pH 3.5 and 3.9) and Versatic 10 (at pH 7 and 8) were further investigated. Furthermore based on McCabe-Thiele method, two extraction stages and one stripping stage (using HCl acid with concentration of 2 M for Versatic 10 and 3 M for D2EHPA) was practiced in continuous runs. Merits of Versatic 10 in comparison to D2EHPA are higher selectivity for Ca and Mg, faster phase disengagement, no detrimental change in viscosity due to shear amount of metal extraction and lower acidity in stripping. On the other hand D2EHPA has less aqueous solubility and is capable of removing Mg and Ca simultaneously even at higher Ca loading (A/O in continuous runs > 1). In general, shorter residence time (~ 2 min), lower temperature (~23 °C), lower pH values (6.5-7.0 for Versatic 10 and 3.5-3.7 for D2EHPA) and a moderately low A/O value (< 1:1) would cause removal of 100% of Ca and nearly 100% of Mg while keeping Li loss less than 4%, much lower than the conventional precipitation in which 20% of Li is lost.