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Working cycles of gasoline and diesel internal combustion engines
No full textTyön tavoitteena oli tutustua bensiini- ja dieselkäyttöisten polttomoottorien työkiertoihin ja niiden mekaanisiin toteutuksiin. Työssä tarkasteltiin työkiertojen toteutusta kaksi- ja nelitahtisina sekä kuvattiin toimintaan tarvitavia komponentteja. Lisäksi esiteltiin valikoituja vaihtoehtoisia moottorikonsepteja, kuten Wankel-kiertomäntämoottori, kuusitahtiperiaatteeseen perustuva moottori ja SPCCI-tekniikka. Työn lopussa käsiteltiin polttomoottoreiden termodynamiikkaa, jossa johdettiin Otto- ja Dieselkiertojen lämpöhyötysuhteet
Joukkuevoimisteluliikkeiden nimitykset ja niiden alueellinen vaihtelu Pohjois-Pohjanmaan ja Uudenmaan välillä
No full textKandidaatintutkielmassani käsittelen joukkuevoimisteluliikkeiden nimityksiä ja niiden alueellista vaihtelua Pohjois-Pohjanmaan ja Uudenmaan välillä. Tutkin tasapainoliikkeiden, hyppyjen ja vartalonliikkeiden nimitysten kautta kyseisen urheilulajin harrastajien slangia eli erikoiskieltä. Tämän lisäksi tutkin esiintyykö nimitysten käyttömäärässä eroavaisuuksia kahden eri maakunnan harrastajien välillä. Tutkielmani on teoreettisilta lähtökohdiltaan sosiolingvististä kielentutkimusta, tarkemmin määriteltynä slangintutkimusta. Tutkimusmetodina käytän Kari Nahkolan sanastolähdejaottelua. Lisäksi esitän aineistossani esiintyvistä nimityksistä lukumääriä ja prosenttiosuuksia, joita vertailemalla teen johtopäätöksiä siitä, esiintyykö eri maakuntien puhujien välillä eroavaisuuksia nimitysten käytössä. Keräsin aineistoni kyselylomakkeella.
Tutkielmani osoittaa, että suurin osa joukkuevoimistelussa käytettävistä nimityksistä on yhdyssanoja tai sanaliittoja, joita suomen kielessä ei ole aikaisemmin ollut. Yhdyssanojen tai sanaliittojen osana on usein metafora. Aineistoni perusteella joukkuevoimisteluliikkeiden yleisimmät nimitykset ovat pääasiassa samat Pohjois-Pohjanmaalla ja Uudellamaalla. Muutoin aineistossani esiintyy paljon maakuntakohtaisia nimityksiä, joita ei lainkaan mainita toisen maakunnan vastauksissa
Crisis Leadership in Public Early Childhood Education Centers in Finland – Relation to Wellbeing at Work and Resilience
No full textAbstract
This study addresses leadership enactment in the context of municipal early childhood education and care (ECE) centers in Finland. It was conducted at a time when the COVID-19 pandemic has spread worldwide, thereby posing new challenges to the ECE leadership. The research draws from crisis leadership and resilience theories to address the following questions: How does crisis leadership link to organization- and individual-level resilience? What kind of expectations are placed on crisis leadership? We understand resilience as one of the key elements of wellbeing at work in todayʼs complex working life. This study conceptualizes crisis leadership as a context-dependent phenomenon constituted by shared meanings and relationships among leaders and practitioners in ECE centers. The data was collected through online focus group interviews with ECE leaders, teachers and researchers. The interviews were conversational in nature and guided by a semistructure of themes. The discussions were analyzed with theory-based content analysis. The aim was to recognize the key elements of good crisis leadership.Abstract
This study addresses leadership enactment in the context of municipal early childhood education and care (ECE) centers in Finland. It was conducted at a time when the COVID-19 pandemic has spread worldwide, thereby posing new challenges to the ECE leadership. The research draws from crisis leadership and resilience theories to address the following questions: How does crisis leadership link to organization- and individual-level resilience? What kind of expectations are placed on crisis leadership? We understand resilience as one of the key elements of wellbeing at work in todayʼs complex working life. This study conceptualizes crisis leadership as a context-dependent phenomenon constituted by shared meanings and relationships among leaders and practitioners in ECE centers. The data was collected through online focus group interviews with ECE leaders, teachers and researchers. The interviews were conversational in nature and guided by a semistructure of themes. The discussions were analyzed with theory-based content analysis. The aim was to recognize the key elements of good crisis leadership
Vapor-Assisted Catalysis Enables Precise Construction of MOF-Derived Hierarchical Carbon Nanoarrays for High-Performance Supercapacitors
No full textAbstract
The synthesis of MOF-derived carbons with high surface area and conductivity is challenged by a fundamental trade-off between architectural preservation and catalytic graphitization. Here, we introduce a spatially decoupled, vapor-assisted pyrolysis strategy where a Co-MOF precursor array is physically separated from a vapor-generating Zn-MOF auxiliary. During pyrolysis, a remote Zn vapor flux simultaneously preserves the precursor's nanosheet morphology by suppressing Co nanoparticle aggregation and catalytically grows dense carbon nanotube (CNT) arrays. This process yields an integrated 0D–1D–2D hierarchical carbon architecture with high surface area and graphitization. As a self-supporting supercapacitor electrode, the optimized material delivers a specific capacitance of 360 F g−1, excellent rate capability (53% retention at 50 A g−1), and robust cycling stability. Mechanistic studies and density functional theory calculations confirm the pivotal role of Zn vapor in modulating Co catalysis for morphology control and reveal a synergy between heteroatoms and cobalt that optimizes K+ storage kinetics. This remote-regulation strategy establishes a generalizable platform for designing hierarchical carbon materials for advanced energy storage.Abstract
The synthesis of MOF-derived carbons with high surface area and conductivity is challenged by a fundamental trade-off between architectural preservation and catalytic graphitization. Here, we introduce a spatially decoupled, vapor-assisted pyrolysis strategy where a Co-MOF precursor array is physically separated from a vapor-generating Zn-MOF auxiliary. During pyrolysis, a remote Zn vapor flux simultaneously preserves the precursor's nanosheet morphology by suppressing Co nanoparticle aggregation and catalytically grows dense carbon nanotube (CNT) arrays. This process yields an integrated 0D–1D–2D hierarchical carbon architecture with high surface area and graphitization. As a self-supporting supercapacitor electrode, the optimized material delivers a specific capacitance of 360 F g−1, excellent rate capability (53% retention at 50 A g−1), and robust cycling stability. Mechanistic studies and density functional theory calculations confirm the pivotal role of Zn vapor in modulating Co catalysis for morphology control and reveal a synergy between heteroatoms and cobalt that optimizes K+ storage kinetics. This remote-regulation strategy establishes a generalizable platform for designing hierarchical carbon materials for advanced energy storage
Optimizing Fe(II)/Fe(III)-bearing magnesium silicate glasses for applications in supplementary cementitious materials
No full textAbstract
This study investigates the potential of Fe-bearing magnesium silicate glasses as alternative supplementary cementitious materials (SCMs) for reducing CO2 emissions in Portland cement production, given the limited supply of traditional SCMs. The glass powders were synthesized using a low-temperature sol-gel process and ascorbic acid (AA) as a reducing agent. This route enables controlled partial reduction of Fe3+ to Fe2+ and stabilizes a fraction of the reduced species during heat treatment, without requiring strongly reducing gases (e.g., H2 or CO). The reactivity of the glasses was evaluated through batch dissolution tests revealing significantly higher elemental solubility for the glasses synthesized with AA compared to those produced without additives. By combining dissolution experiments with 57Fe Mössbauer spectroscopy and XPS, we establish a direct link between Fe redox state/coordination (Fe2+ and tetrahedral vs. octahedral Fe3+), silicate network depolymerization, and glass reactivity relevant for SCM use. The higher reactivity is particularly pronounced at low Fe concentrations, attributed to the reduction of Fe3+ to Fe2+, which acts as a network modifier and enhances the solubility. While the solubility slightly decreases with higher Fe concentrations among AA-assisted glasses, it remains remarkably higher than in glasses synthesized without AA. This is attributed to a greater proportion of octahedral Fe3+, facilitated by chelation between AA and Fe. Tetrahedral Fe3+ acts as a network former, whereas octahedral Fe3+ acts as a network modifier that depolymerizes the silicate network and enhances elemental solubility. Overall, AA-assisted glasses with intermediate Fe contents (Fe/(Fe + Mg) = 7–15 mol%) exhibit the highest reactivity, attributable to their higher Fe2+ fraction in the network, making them the most promising candidates for low-CO2 cement applications.Abstract
This study investigates the potential of Fe-bearing magnesium silicate glasses as alternative supplementary cementitious materials (SCMs) for reducing CO2 emissions in Portland cement production, given the limited supply of traditional SCMs. The glass powders were synthesized using a low-temperature sol-gel process and ascorbic acid (AA) as a reducing agent. This route enables controlled partial reduction of Fe3+ to Fe2+ and stabilizes a fraction of the reduced species during heat treatment, without requiring strongly reducing gases (e.g., H2 or CO). The reactivity of the glasses was evaluated through batch dissolution tests revealing significantly higher elemental solubility for the glasses synthesized with AA compared to those produced without additives. By combining dissolution experiments with 57Fe Mössbauer spectroscopy and XPS, we establish a direct link between Fe redox state/coordination (Fe2+ and tetrahedral vs. octahedral Fe3+), silicate network depolymerization, and glass reactivity relevant for SCM use. The higher reactivity is particularly pronounced at low Fe concentrations, attributed to the reduction of Fe3+ to Fe2+, which acts as a network modifier and enhances the solubility. While the solubility slightly decreases with higher Fe concentrations among AA-assisted glasses, it remains remarkably higher than in glasses synthesized without AA. This is attributed to a greater proportion of octahedral Fe3+, facilitated by chelation between AA and Fe. Tetrahedral Fe3+ acts as a network former, whereas octahedral Fe3+ acts as a network modifier that depolymerizes the silicate network and enhances elemental solubility. Overall, AA-assisted glasses with intermediate Fe contents (Fe/(Fe + Mg) = 7–15 mol%) exhibit the highest reactivity, attributable to their higher Fe2+ fraction in the network, making them the most promising candidates for low-CO2 cement applications
Eating skills and tongue movements in one-year-old children with a neonatal diagnosis of ankyloglossia
No full textBooks about Japanese folklore written by Westerners in the late 19th century and early 20th century
No full textTutkielmani aiheena on länsimaalaisten 1800-luvun lopulla ja 1900-luvun alussa kirjoittamat teokset japanilaisesta folkloresta. Tutkin missä määrin nämä teokset heijastelivat oman aikansa tieteellisiä käytäntöjä ja trendejä. Vaikuttivatko valitsemieni teosten taustalla samat motiivit, jotka ajoivat monia tutkijoita maailmalle tutkimaan eri kansojen folklorea? Noudattivatko teosten kirjoittajat aikansa folkloristisen tutkimuksen teorioita ja metodeja?
Päälähteinäni oli yhdeksän teosta seitsemältä eri kirjoittajalta. Teokset on valikoitu Oulun yliopiston Western Books on Asia -tietokannasta. Valintaan vaikutti ajallinen rajaus vuosiin 1870–1910 sekä kielellinen rajaus englanninkielisiin teoksiin. Tämän lisäksi huomioin, että mukaan tulee sekä mies- että naiskirjailijoita. Lähteiksi muodostuivat Basil Hall Chamberlain, Lafcadio Hearn, William Elliot Griffis, A. B. Mitford, Richard Gordon Smith, Violet M. Pasteur sekä Susan Ballard. Tutkimuskirjallisuudesta mainittakoon tärkeimpänä Jay Peters.
Aiempi tutkimus on keskittynyt lähinnä kahteen tunnetuimpaan kirjoittajaan, vaikka moni muukin on japanilaisesta folkloresta kirjoittanut. Täten tutkimukseni tulee täydentämään aiempaa tutkimusta ja antamaan lisätietoa länsimaalaisten folkloren keruun perinteestä.
Keskeinen tarkastelunäkökulmani on oppihistoriallinen. Rakenteeltaan tutkielmani on temaattinen ja muodostuu kahdesta pääluvusta. Tutkimuksessani käytän laadullisen historiantutkimuksen metodeja ja kontekstualisointia liittääkseni tutkimuskohteeni oikeisiin viitekehyksiin. Käytän myös vertailevaa tutkimusta selvittääkseni lähteissäni mahdollisesti käytettyjä metodeja. Lähdekritiikki kulkee mukana lähteitä tutkittaessa.
Motiivien suhteen lähteeni vastasivat aiempaa tutkimusta ja vahvistivat aiempaa käsitystä modernisaation ja yhteiskunnallisten muutosten vaikutuksesta tieteiden, erityisesti folkloristiikan, kehityksessä. Käytettyjen metodien ja teorioiden suhteen lähteeni noudattivat aiemmassa tutkimuksessa määriteltyjä trendejä joissain määrin. Lähteistä on havaittavissa, että kirjoittajat, joita motivoi pelko kansantarujen katoamisesta, noudattivat tieteellisiä keinoja enemmän. Vastaavasti kirjoittajat, joita motivoi kiinnostus Japania ja japanilaisuutta kohtaan, eivät kiinnittäneet niinkään huomiota metodiikkaan, vaan tiedon saattamiseen laajan yleisön saataville.
Tutkimuksessani käydään läpi hyvin pieni osa kaikista niistä teoksista, joita japanilaisesta folkloresta kirjoitettiin. Tutkittavaksi olisi hyvä ottaa myös muilla kielillä kirjoitettuja teoksia, jotta saataisiin mahdollisimman kattava käsitys tieteellisen folkloristiikan vaiheista. Uutta lähestymistapaa voisi löytää ottamalla mukaan myös japanilaisten omat folkloristiset teokset ja vertaamalla niitä länsimaalaisiin teoksiin
Sustainable Massive Connectivity Maximization Scheduling Scheme for 6G
No full textAbstract
This paper proposes a scalable and energy-efficient scheduling framework tailored for massive machine-type communications (mMTC) in future 6G networks. Motivated by the dual challenges of massive connectivity and strict energy constraints, we introduce a new cooperative multi-cell uplink scheme that jointly optimizes user scheduling, power allocation, and interference management under finite block length (FBL) constraints. While prior studies have explored energy efficiency (EE) or connectivity separately, they often neglect FBL effects and lack scalable, interference-aware coordination across multi-cell NOMA deployments. Leveraging non-orthogonal multiple access (NOMA), our framework addresses both intra- and inter-cell interference through a multi-objective optimization problem that simultaneously maximizes EE and connectivity. To solve the problem, we develop the Sustainable and Reliable Scheduling for Massive Machine Type Communication using NOMA (SRS-MTCN) algorithm, integrating channel-aware user clustering, interference-aware resource allocation, and iterative power optimization. Simulation results demonstrate that the proposed approach performs significantly better than state-of-the-art baselines in dense deployments, achieving up to 35−58% EE improvement in medium-density regimes ( 16−32 devices/m2), while ensuring robust scalability and reliability in ultra-dense scenarios exceeding 40 devices/m2. These results illustrate its suitability for sustainable 6G mMTC networks operating under FBL and energy constraints.Abstract
This paper proposes a scalable and energy-efficient scheduling framework tailored for massive machine-type communications (mMTC) in future 6G networks. Motivated by the dual challenges of massive connectivity and strict energy constraints, we introduce a new cooperative multi-cell uplink scheme that jointly optimizes user scheduling, power allocation, and interference management under finite block length (FBL) constraints. While prior studies have explored energy efficiency (EE) or connectivity separately, they often neglect FBL effects and lack scalable, interference-aware coordination across multi-cell NOMA deployments. Leveraging non-orthogonal multiple access (NOMA), our framework addresses both intra- and inter-cell interference through a multi-objective optimization problem that simultaneously maximizes EE and connectivity. To solve the problem, we develop the Sustainable and Reliable Scheduling for Massive Machine Type Communication using NOMA (SRS-MTCN) algorithm, integrating channel-aware user clustering, interference-aware resource allocation, and iterative power optimization. Simulation results demonstrate that the proposed approach performs significantly better than state-of-the-art baselines in dense deployments, achieving up to 35−58% EE improvement in medium-density regimes ( 16−32 devices/m2), while ensuring robust scalability and reliability in ultra-dense scenarios exceeding 40 devices/m2. These results illustrate its suitability for sustainable 6G mMTC networks operating under FBL and energy constraints
Bayesian Parametric Curve Prediction for Ferrite Onset Temperature During Cooling of Steel with Multiple Output Gaussian Process Prior
No full textAbstract
The continuous cooling diagram (CCT-diagram) is a convenient representation of how austenite decomposes into different microstructures during cooling. It can be applied for designing suitable cooling paths in order to achieve desired mechanical properties. Since the decomposition of austenite depends on the chemical composition of the steel, understanding how different components affect the time and temperature of the transformation provides a valuable tool in choosing a suitable composition. Several linear and non-linear methods have been presented earlier for predicting CCT-diagrams. These include linear regression models, machine-learning methods, and different neural network-based models. Generally, these methods do not provide any uncertainty measures around their predicted curves, large learning data sets may be needed and they may have problems with extrapolation. In this study rigid parametric modeling is combined with a non-parametric Bayesian approach to fit model parameters. This approach yields an interpretable and simple parametric curve function and accounts for complex interrelations present in the alloying elements. Special property of the method is that it produces probabilistic uncertainty estimates for the CCT-curve for a given steel. This reflects representativeness of the composition of that particular steel in the learning set.Abstract
The continuous cooling diagram (CCT-diagram) is a convenient representation of how austenite decomposes into different microstructures during cooling. It can be applied for designing suitable cooling paths in order to achieve desired mechanical properties. Since the decomposition of austenite depends on the chemical composition of the steel, understanding how different components affect the time and temperature of the transformation provides a valuable tool in choosing a suitable composition. Several linear and non-linear methods have been presented earlier for predicting CCT-diagrams. These include linear regression models, machine-learning methods, and different neural network-based models. Generally, these methods do not provide any uncertainty measures around their predicted curves, large learning data sets may be needed and they may have problems with extrapolation. In this study rigid parametric modeling is combined with a non-parametric Bayesian approach to fit model parameters. This approach yields an interpretable and simple parametric curve function and accounts for complex interrelations present in the alloying elements. Special property of the method is that it produces probabilistic uncertainty estimates for the CCT-curve for a given steel. This reflects representativeness of the composition of that particular steel in the learning set