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Fulfill the dream: advancing skateboarders’ agency through experimenting and interaction with urban infrastructure
No full textSkateboarders have a passionate relationship with urban infrastructures, which offer them an endless playground but also provoke the imagination to rework the built environment. This paper analyses a case study of Pirkanmaan Kaarikoirat, a skateboarding association from Tampere, Finland, and it unravels the experimental interaction between the skateboarders and the pulp-drying building infrastructure that was transformed into the Kenneli DIY skatepark. We approach urban infrastructure as a base that offers opportunities for a new kind of growth, both in a material and social sense. Following experimental interaction demonstrates the capacity of infrastructure to allow novel learning processes, partnerships, and material ontologies that have wider implications in the politics of urban development.Peer reviewe
Friends from the Past, Friends for the Future: Exploring How Young Refugees’ Friendship Practices Change and Endure Through Life Transitions
No full textFor unaccompanied young people, forced migration and resettlement take place within intersecting life transitions into new social, cultural and environmental conditions. Previous research shows that peer networks provide crucial support for young refugees as they navigate through these transitions. This qualitative study used a practice-theoretical lens to better understand how friendships are made and participated in over time as young refugees build new lives in Finland. Using thematic interviews with young refugees on their past, present and future friendships, this study explores how changing conditions enable or constrain the practices through which friendships are maintained. Findings show that some friendship practices endured or evolved within changed conditions related to safety, gender, language, geography and technology. Findings also show that friendships made in residential care had continuing significance in young refugees’ adulthoods, suggesting that facilitating the development of these friendships has positive long-term implications for young refugees’ resettlement and well-being.Peer reviewe
Long-Horizon Direct Model Predictive Control for Medium-Voltage Converters Connected to a Distorted Grid
No full textLong-horizon finite control set model predictive control (FCS-MPC) is known for its superior performance, particularly when applied to complex, higher order systems, such as grid-connected converters with LCL filters. This article proposes a long-horizon FCS-MPC method that effectively operates such systems even in the presence of time-varying model parameters and distorted grid voltage with variable harmonic content. To do so, the proposed method incorporates information about the grid voltage distortion when generating the reference trajectories of the controlled variables, namely, the grid and converter currents and the filter capacitor voltage. In addition, a fast estimation algorithm continuously updates the grid- and converter-side reactances, thus ensuring robustness to parameter variations in the system model. Real-time tests conducted in a hardware-in-the-loop environment validate the effectiveness of the proposed control approach across various operating conditions.Peer reviewe
Tiimityöhön kykenevän tekoälyn toteuttaminen
Get PDFTässä kandidaatintyössä selvitettiin, kuinka vahvistusoppimista voidaan hyödyntää tekoälyagentin toteuttamisessa padel-peliin, jossa tehokas suoriutuminen edellyttää pelaajien välistä yhteistyötä. Tavoitteena oli rakentaa tekoäly, joka kykenee tekemään tilannekohtaisia ja tiimipohaisia päätöksiä nopeasti muuttuvassa peliympäristössä. Agenttien koulutus toteutettiin Unity ML-Agents -alustalla käyttäen MA-POCA-algoritmia, joka mahdollistaa useiden agenttien yhteistoiminnan keskitetyn kriitikon avulla. Koulutusympäristö, havaintotiedot, toimintotilat ja palkitsemislogiikka suunniteltiin padelin sääntöjen ja pelidynamiikan pohjalta.
Tulokset osoittivat, että self-play menetelmällä koulutetut agentit oppivat nopeammin ja kehittyivät monipuolisemmiksi kuin ilman self-playta koulutetut agentit. Ne pystyivät pelaamaan pidempiä ja hallitumpia palloralleja sekä tekemään strategisesti järkevämpiä päätöksiä. Oppimisen onnistumisen kannalta palkkiorakenteen huolellinen suunnittelu osoittautui keskeiseksi tekijäksi.
Tutkielmassa käsitellään myös tekoälyn ja koneoppimisen keskeisiä peruskäsitteitä, erityisesti vahvistusoppimisen taustateoriaa, kuten Markovin päätösprosesseja, syväoppimista ja multi-agent menetelmiä. Lisäksi työssä vertaillaan kehitettyä lähestymistapaa perinteisiin sääntöpohjaisiin tekoälyratkaisuihin ja esitetään jatkokehitysmahdollisuutena vahvistusoppimisen yhdistäminen influence map -tekniikkaan agenttien taktisen päätöksenteon tukemiseksi
Exploring the role of citizen science in indoor air quality monitoring and sustainable development
Get PDFThe air we breathe contains what we need to live but it also contains pollutants with various health implications from short- and long-term exposure. While we understand the impact of air pollution in outdoor environments, the place where people spend up to 90% of their time is left unattended – that is, indoors. Studying indoor air quality is a challenge due to the ethical and high costs associated with large measuring devices. However, due to the development of low-cost indoor air quality monitoring devices, cloud-based services, and the portable new devices, indoor air becomes possible to study in detail. The challenge remains on how researchers can gather this data.
In the spirit of sustainability which considers societal and administrative perspectives, community based monitoring and citizen science become useful tools. Citizen science provides practises of collaborative projects, while community based monitoring in turn gives empowers citizens to make observations on their surroundings. Combined, these can help improve urban development and specifically fill the gap in indoor air quality research, while producing socially active and empowered communities to engage with policy. Collecting data directly from individual homes is important in understanding the variable factors influencing indoor air quality since this type of detail has been missed with previous studies modelling indoor environments.
This study follows the experiences of 17 participants in an Indoor Air Quality Pilot Project at Tampere University in 2024 lasting two and a half weeks. The participants were given AirGradient low-cost air quality monitoring devices to their homes, contributing to community based monitoring. Participatory practises were also implemented through two workshops: at the beginning and the end of the project. The workshops gave participants an overview of air quality matters, the research taking place during the project, and factors influencing their home environments. Through anonymous qualitative and quantitative questionnaires filled out by participants at the beginning and at the end of the project, this study explores how citizen science and community-based monitoring can enhance indoor air quality research and contribute to sustainable urban development.
The results of the questionnaires showed that participant motivations for joining the project were personal wellbeing and curiosity surrounding air pollution in their homes while some surprising findings they identified were on PM2.5 and CO2 readings. Key behavioural changes were also identified through the questionnaires, as participants reported increased interest in IAQ, policy regarding IAQ, and citizen science as a whole. Participants also stated feeling more empowered regarding their home environments and showed an increased familiarity with the central topics of IAQ between the beginning and end of the workshops and measurements. This familiarity spread to participant sentiments toward having their home IAQ data being uploaded to cloud services, and participants said they would be more comfortable with their data being used for similar projects in the future.
The behavioural changes can be attributed to the use of citizen science practises where participants are not simply involved to collect data but were actively engaged on the research topics. Through workshops, they were taught how to interpret device results which contributed to their learning, familiarity with topics, and sense of empowerment. These results impact the usability of community based monitoring in indoor air quality monitoring research and show how these methods impact the sustainability of future research in this challenging field. Previous modelling of indoor air quality relies on outdoor factors and general building specifications, which overlooks individual behaviour influences on indoor air quality. Community based monitoring therefore fills the gap by providing more detailed and qualitative data to be used in research of home environments
Comparative Study of Advanced Heatsink Structures for Improved Thermal Performance in Axial Flux Motors
No full textAdditive manufacturing has enabled the use of advanced geometries such as lattice-structures in heatsinks. This study investigates the thermal performance of various advanced heatsink designs in the context of cooling the windings of an axial flux motor using active air cooling. Physical samples of the heatsinks are additively manufactured from an aluminum alloy and tested under realistic airflow conditions. The heatsink designs are compared against an optimized conventional finned geometry based on the measured thermal resistance at a given fan speed. This ensures that the results are representative of real-world use cases and applicable in practical solutions. The results indicate that airfoil-shaped pins can slightly outperform conventional straight fins in thermal resistance while weighing less. In terms of mass-based relative performance, the rhombi octet lattice structure outperformed the other prototypes. These findings reinforce conventional design principles in terms of absolute performance while suggesting that lattice structures can provide higher relative performance in certain weight sensitive applications.Peer reviewe
Memory Optimized, High Signal Quality Direct Digital Frequency Synthesizer on an FPGA
No full textDirect digital frequency synthesis is a method for generating digital samples of periodic analog signals. It has been broadly used for decades in applications such as digital radios and radars. The common approaches utilize read-only memory (ROM) for creating amplitude values, and a lot of research focus has been put into reducing the required ROM size. In this paper, we are presenting a memory optimized Direct Digital Frequency Synthesizer (DDFS) architecture that applies the 3rd order Taylor series approximation for amplitude computation. To evaluate the architecture performance, also traditional ROM-based architecture is introduced. Both approaches are implemented using VHDL code on a field programmable gate array (FPGA). The FPGA resource utilization, memory consumption, and signal quality are analyzed and compared with other recently published DDFS approaches. Based on the simulation and implementation results, the proposed new architecture consumes only 270 bits of memory and has the output signal spurious free dynamic range (SFDR) of -103.6 dBc.Peer reviewe
Musiikkidiplomatia : Tapaustutkimus Blinkenin ulkoministeriön Global Music Diplomacy -hankkeesta
Get PDFMusiikkidiplomatia lukeutuu osaksi julkisuusdiplomatiaa, jossa on kyse poliittisen toimijan pyrkimyksestä edistää julkikuvaansa kansainvälisen yleisön silmissä ulkopoliittisten intressien edistämiseksi. Musiikkidiplomatiassa musiikki välineellistetään diplomaattiseksi työkaluksi, ja aiemmissa tutkimuksissa tämän on katsottu liittyvän niin sanottuun pehmeään vallankäyttöön. Joseph S. Nye on määritellyt pehmeän vallan kyvyksi vaikuttaa muihin vetovoimalla (attraction) ja suostuttelulla (persuasion) pakottamisen tai taloudellisten kannustimien sijaan.
Osana kansallista musiikkidiplomatiaa Yhdysvaltain ulkoministeriö lanseerasi ulkoministeri Antony Blinkenin johdolla The Global Music Diplomacy Initiative (GMD) -hankkeen 27.9.2023, joka yhdisti yhtenäiseen kehykseen ulkoministeriön musiikilliset julkisuusdiplomatiaohjelmat ja loi merkittäviä uudistuksia. Keskeisiä uudistuksia olivat tiivistynyt yhteistyö ulkoministeriön ja yksityisen sektorin yritysten (esim. YouTube) välillä kansallisen musiikkidiplomatian toteutuksessa, kansainvälisten artistilähettiläiden (U.S Global Music Ambassadors) nimitykset diplomaattisiin tehtäviin sekä musiikilliset sisältöuudistukset Yhdysvaltain lähetystöjen ja konsulaattien kautta ulkomaiselle nuorelle väestölle tarjottuun englannin kielen opetukseen.
Tässä tutkimuksessa tarkastellaan sitä, miten Yhdysvaltain ulkoministeriön GMD-hanke toteuttaa pehmeää vallankäyttöä. GMD-hankkeen tarkastelussa nojataan teoreettisesti ja analyyttisesti pehmeän vallan (soft power) teoriaan, uuden julkisuusdiplomatian viitekehykseen (the new public diplomacy, NPD) sekä Yhdysvaltain kulttuuridiplomatiaa käsittelevään tutkimuskirjallisuuteen, jossa on osoitettu, että Yhdysvallat on aiemmin käyttänyt musiikkia ja muusikkoja strategisena työkaluna ulkopolitiikassa.
Tutkimus on tapaustutkimus, jonka analyysimenetelmänä käytetään teoriaohjaavaa sisällönanalyysiä, joka yhdistää aineistolähtöisen tarkastelun ja teoreettisen tulkinnan. Tutkimuksen aineistona hyödynnetään GMDhankkeeseen suoraan liittyvää materiaalia, kuten GMD-hankkeen verkkosivuja, Yhdysvaltain ulkoministeriön verkkosivuja, ulkoministeriön koulutus- ja kulttuurisuhteiden viraston (ECA) verkkosivuja sekä ECA:n englannin kielen musiikillisia opetusmateriaaleja.
Tutkimuksen perusteella voidaan havaita, että GMD-hanke kokoaa yhteen erilaisia kulttuuridiplomaattisia toimintoja, joihin kaikkiin liittyy strateginen pyrkimys pehmeään vallankäyttöön. Hankkeen eri osa-alueet ja uudistukset kytkeytyvät Nyen määritelmiin pehmeän vallan lähteistä, eli valtion kulttuuriin, valtion poliittisiin arvoihin sekä valtion ulkopoliittiseen legitimiteettiin. Tutkimus osoittaa, että GMD-hankkeen rakenteellisilla ja sisällöllisillä uudistuksilla Yhdysvallat pyrkii vaikuttamaan ulkomaiseen yleisöön hyödyntämällä muun muassa valtion ja yksityisen sektorin välistä yhteistyötä, tunnettuja artistilähettiläitä diplomaattisina toimijoina, musiikillista englannin kielen opetusta sekä ammatti- ja kulttuurivaihto-ohjelmia. GMD-hankkeen voidaan katsoa edustavan Yhdysvaltain pehmeää vallankäyttöä ja pyrkivän etenkin pitkäjänteiseen vaikuttamiseen. Narratiivisesti hanke pyrkii rakentamaan kuvan, jossa Yhdysvallat näyttäytyy demokraattisena, monimuotoisena ja oikeudenmukaisena kansainvälisenä toimijana, jolla on pyrkimys pitkäjänteiseen monenkeskiseen yhteistyöhön. Yleisemmin tutkimus osoittaa, että musiikki voidaan implementoida hyvin moniulotteiseksi työkaluksi osana valtion julkisuusdiplomatiaa
Health behaviors, health, sociodemographic factors, and school success in adolescence as risk factors for injury deaths: a longitudinal study
No full textBackground: Injuries are a substantial cause of mortality in young adults. Previous longitudinal studies on the impact of adolescent health behaviors, health, sociodemographic factors, and school success on injury deaths are lacking. We examined the influence of these factors in adolescence on later injury death. Methods: We conducted a population-based longitudinal study with an average 26-year follow-up, using questionnaire data from the Adolescent Health and Lifestyle Survey (AHLS) and register data. Adolescents aged 14, 16, or 18 years who answered the survey between 1981 and 1997 were included. A total of 47 326 individuals responded to the survey. Causes of death were obtained from the Finnish official Cause-of-Death Register. Cox regression model was used to analyze the associations between explanatory variables and injury death. Adjusted hazard rations (aHR) and 95% confidence intervals (CI) were computed. 14-year-olds and 16–18-year-olds were analyzed separately by sex. Results: We identified 550 injury deaths, 432 in men and 118 in women. The mean age at death was 30 years. Drinking style (recurring drunkenness 14-year-old girls aHR 4.35 CI 1.00–19.02 and boys aHR 4.02, CI 1.62–10.00; 16–18-year-old girls aHR 2.63, CI 1.13–6.13 and boys aHR 1.70, CI 1.07–2.71) was associated with injury death in all subgroups. Smoking (girls aHR 2.00, CI 1.21–3.33 and boys aHR 1.86, CI 1.42–2.44) and stress symptoms (two or more/day girls aHR 2.34, CI 1.32–4.14 and boys aHR 2.07, CI1.39–3.07) were associated with injury death in 16–18-year-olds. Not living with both parents also increased the risk of injury death in boys. Conclusion: Our findings suggest that adolescents who drift into risky health behavior and struggle with stress symptoms are at higher risk for injury death later in life. More support should, therefore, be allocated to these groups during adolescence.Peer reviewe
High-resolution mapping of residential wood burning heat sources using Energy Performance Certificates: A case study of England and Wales
No full textBackground: Particulate matter emissions from residential wood burning are rising in many countries. Long-term exposure to fine particulate matter is strongly linked with adverse health effects including cardiovascular and respiratory disease. Policymakers and scientists need accurate tools to identify residential wood burning hotspots. However, current methods rely on spatially-misaligned, out-of-date data sources, reducing their practical utility and portability to other contexts. Furthermore, the socio-economic characteristics of residential wood burning in high income countries are poorly understood. Methods: We used open data from 26 million Energy Performance Certificates (EPCs) for properties in England and Wales from 2009–2025 to map the concentration and prevalence of wood burners within small areas. We evaluated our method against the UK national wood burning emissions inventory using national air pollution monitoring networks. We used novel open data linkages to characterise associations between area-level prevalence of wood burners and socio-economic factors including deprivation, ethnicity, and age. Findings: We identified substantial spatial heterogeneity in the concentration of wood burners, with the highest concentrations in affluent urban areas. Our concentration metric was more strongly correlated with peaks in winter PM2.5 at urban monitoring sites than estimates from the UK national emissions inventory. Prevalence of wood burners was positively correlated with age and negatively correlated with measures of social deprivation. Prevalence of wood burners in EPCs has increased since 2009. Conclusions: EPCs are a valuable data source which policymakers can use to target local interventions or extend existing restrictions on solid fuel burning. Our method is transparent, up-to-date, and portable to other countries where similar EPC data is available. The relationship between social deprivation and prevalence of wood burning heat sources highlights important issues of environmental justice. Epidemiological analyses of wood smoke exposures and health should carefully account for the confounding effects of age, deprivation, and ethnicity.Peer reviewe