1,327 research outputs found
Videogames as a learning environment:English language teaching and intercultural communication
Abstract. The objective of this study is to examine the use of videogames as teaching tools for spoken intercultural communication, and to identify possible obstacles to their use. The materials â the national core curriculum and assorted studies â were examined through close reading. The aim was to identify benefits of using games and possible obstacle-sources. The collected data was analyzed through qualitative content analysis, to sort the findings, and theorize what promotes or obstructs the use of games. Main theoretical framework forms out of the national core curriculum, research on English as lingua franca and research on learning and videogames. The results suggest that videogames are a viable option for learning intercultural communication, but numerous obstacles might inhibit their use. These obstacles include, among others, time constraints, videogame design, and objectives of basic education. In the future, empirical research is required to confirm the viability of using videogames more actively as parts of the Finnish education system.TiivistelmĂ€. TĂ€mĂ€n tutkielman tavoitteena on tarkastella videopelien kĂ€yttöÀ opetusvĂ€lineinĂ€ puhutun kulttuurienvĂ€lisen kommunikaation opetuksessa, sekĂ€ tunnistaa mahdollisia esteitĂ€ niiden kĂ€ytölle. Aineistoa â perusopetuksen opetussuunnitelman perusteita ja valikoituja tutkielmia â tutkittiin lĂ€hiluvun kautta. NĂ€in kerĂ€ttyjĂ€ löydöksiĂ€ tarkasteltiin kvalitatiivisen sisĂ€ltöanalyysin kautta. Tavoitteena oli eritellĂ€ löydöksiĂ€ ja teoretisoida mikĂ€ edistÀÀ tai estÀÀ videopelien kĂ€yttöÀ. Teoreettinen kehys muodostuu perusopetuksen opetussuunnitelmasta, tutkimuksesta englannin kieleen lingua francana sekĂ€ tutkimuksesta oppimiseen ja videopeleihin. Tulosten perusteella vaikuttaa siltĂ€, ettĂ€ pelejĂ€ voi kĂ€yttÀÀ kulttuurienvĂ€lisen kommunikaation opetuksessa. On kuitenkin huomattava, ettĂ€ useita esteitĂ€ niiden kĂ€ytölle löytyi. NĂ€ihin esteisiin lukeutuu muun muassa ajalliset rajoitteet, videopelien suunnittelu sekĂ€ perusopetuksen tavoitteet. Tulevaisuudessa tarvitaan empiiristĂ€ tutkimusta varmentamaan, onko videopelejĂ€ mahdollista hyödyntÀÀ nykyistĂ€ aktiivisemminosana suomalaista opetusjĂ€rjestelmĂ€
Development of printing methods and substrate treatments for efficient li-ion battery systems
Abstract. The manufacturing of Lithium-ion batteries is changing due to environmental concerns. Scientists are seeking non-toxic and environmentally friendly materials to improve the sustainability of battery fabrication. In this thesis, Cyrene was researched as a suitable solvent for the fabrication of cathode layers. Various surface treatments of the substrates were used to increase the wetting of substrates to achieve better printability and, consequently, better cathode layers.
After developing and tuning the printing process, the printed cathodes were used to fabricate Pouch batteries. The results indicate that different surface treatments influence the cathode material adhesion to the substrate and overall performance of the batteries.Painomenetelmien ja substraatin kÀsittelymenetelmien kehittÀminen tehokkaille litiumioniakkujÀrjestelmille. TiivistelmÀ. Litiumioniakkujen valmistamista pyritÀÀn muuttamaan ympÀristöystÀvÀllisemmÀksi. Alan tutkijat etsivÀt myrkyttömiÀ materiaaleja tehdÀkseen akkujen valmistuksesta ympÀristön kannalta kestÀvÀmpiÀ. TÀssÀ työssÀ tutkittiin, soveltuuko Cyrene liuottimeksi katodikerrosten valmistuksessa. Erilaisia pintakÀsittelymenetelmiÀ kÀytettiin lisÀÀmÀÀn substraattien vettymistÀ paremman painettavuuden ja siten parempien katodikerrosten saavuttamiseksi.
Painoprosessin kehitystyön ja sÀÀtÀmisen jÀlkeen painettuja katodeja kÀytettiin pussimallin akkujen valmistukseen. Tulokset osoittivat, ettÀ erilaiset pintakÀsittelyt vaikuttavat katodimateriaalin tarttumiseen substraattiin sekÀ akkujen yleiseen suorituskykyyn
Uplink data measurement and analysis for 5G eCPRI radio unit
Abstract. The new 5G mobile network generation aims to enhance the performance of the cellular network in almost every possible aspect, offering higher data rates, lower latencies, and massive number of network connections. Arguably the most important change from LTE are the new RU-BBU split options for 5G promoted by 3GPP and other organizations. Another big conceptual shift introduced with 5G is the open RAN concept, pushed forward by organizations such as the O-RAN alliance. O-RAN aims to standardize the interfaces between different RAN elements in a way that promotes vendor interoperability and lowers the entry barrier for new equipment suppliers. Moreover, the 7-2x split option standardized by O-RAN has risen as the most important option within the different low layer split options. As the fronthaul interface, O-RAN has selected the packet-based eCPRI protocol, which has been designed to be more flexible and dynamic in terms of transport network and data-rates compared to its predecessor CPRI. Due to being a new interface, tools to analyse data from this interface are lacking.
In this thesis, a new, Python-based data analysis tool for UL eCPRI data was created for data quality validation purposes from any O-RAN 7-2x functional split based 5G eCPRI radio unit. The main goal for this was to provide concrete KPIs from captured data, including timing offset, signal power level and error vector magnitude. The tool produces visual and text-based outputs that can be used in both manual and automated testing. The tool has enhanced eCPRI UL datapath testing in radio unit integration teams by providing actual quality metrics and enabling test automation.Uplink datamittaukset ja -analyysi 5G eCPRI radiolla. TiivistelmÀ. Uusi 5G mobiiliverkkogeneraatio tuo mukanaan parannuksia lÀhes kaikkiin mobiiliverkon ominaisuuksiin, tarjoten nopeamman datasiirron, pienemmÀt viiveet ja valtavat laiteverkostot. Luultavasti tÀrkein muutos LTE teknologiasta ovat 3GPP:n ja muiden organisaatioiden ehdottamat uudet radion ja systeemimoduulin vÀliset funktionaaliset jakovaihtoehdot. Toinen huomattava muutos 5G:ssÀ on O-RAN:in ajama avoimen RAN:in konsepti, jonka tarkoituksena on standardisoida verkkolaitteiden vÀliset rajapinnat niin, ettÀ RAN voidaan rakentaa eri valmistajien laitteista, laskien uusien laitevalmistajien kynnystÀ astua verkkolaitemarkkinoille. O-RAN:n standardisoima 7-2x funktionaalinen jako on noussut tÀrkeimmÀksi alemman tason jakovaihtoehdoista. Fronthaul rajapinnan protokollaksi O-RAN on valinnut pakettitiedonsiirtoon perustuvan eCPRI:n, joka on suunniteltu dynaamisemmaksi ja joustavammaksi datanopeuksien ja lÀhetysverkon suhteen kuin edeltÀvÀ CPRI protokolla. Uutena protokollana, eCPRI rajapinnalle soveltuvia data-analyysityökaluja ei ole juurikaan saatavilla.
TÀssÀ työssÀ luotiin uusi pythonpohjainen data-analyysityökalu UL suunnan eCPRI datalle, jotta datan laatu voidaan mÀÀrittÀÀ millÀ tahansa O-RAN 7-2x funktionaaliseen jakoon perustuvalla 5G eCPRI radiolla. Työkalun pÀÀtarkoitus on analysoida ja kuvata datan laatua laskemalla datan ajoitusoffsettia, tehotasoa, sekÀ EVM:ÀÀ. Työkalu tuottaa tulokset visuaalisena ja tekstipohjaisena, jotta analyysia voidaan tehdÀ niin manuaalisessa kuin automaattisessa testauksessa. Työkalun kÀyttöönotto on tehostanut UL suunnan dataputken testausta radio-integrointitiimeissÀ, tarjoten datan laatua kuvaavaa metriikkaa sekÀ mahdollistaen testauksen automatisoinnin
Connected vehicles:organizational cybersecurity processes and their evaluation
Abstract. Vehicles have become increasingly network connected cyber physical systems and they are vulnerable to cyberattacks. In the wake of multiple vehicle hacks, automotive industry and governments have recognized the critical need of cybersecurity to be integrated into vehicle development framework and get manufactures involved in managing whole vehicle lifecycle. The United Nations Economic Commission for Europe (UNECE) WP.29 (World Forum for Harmonization of Vehicle Regulations) committee published in 2021 two new regulations for road vehicles type approval: R155 for cybersecurity and R156 for software update. The latter of these influence also to agricultural vehicle manufacturers, which is the empirical context of this study. Also new cybersecurity engineering standard from International Standardization Organization (ISO) and Society of Automotive Engineers (SAE) organizations change organizations risk management framework. The vehicle manufacturers must think security from an entirely new standpoint: how to reduce vehicle cybersecurity risk to other road users. This thesis investigates automotive regulations and standards related to cybersecurity and cybersecurity management processes. The methodology of the empirical part is design science that is a suitable method for the development of new artifacts and solutions. This study developed an organization status evaluation tool in the form of a questionnaire. Stakeholders can use the tool to collect information about organizational capabilities for comprehensive vehicles cybersecurity management process. As a main result this thesis provides base information for cybersecurity principles and processes for cybersecurity management, and an overview of current automotive regulation and automotive cybersecurity related standards.Verkotetut ajoneuvot : organisaation kyberturvallisuusprosessit ja niiden arviointi. TiivistelmÀ. Ajoneuvoista on tullut kyberhyökkÀyksille alttiita tietoverkkoon yhdistettyjÀ kyberfyysisiÀ jÀrjestelmiÀ. Ajoneuvojen hakkeroinnit herÀttivÀt hallitukset ja ajoneuvoteollisuuden huomaamaan, ettÀ kyberturvallisuus on integroitava osaksi ajoneuvojen kehitysympÀristöÀ ja valmistajat on saatava mukaan hallitsemaan ajoneuvon koko elinkaarta. Yhdistyneiden Kansakuntien Euroopan talouskomission (UNECE) WP.29 (World Forum for Harmonization of Vehicle Regulations) -komitean jÀsenet julkaisivat vuonna 2021 kaksi uutta tyyppihyvÀksyntÀsÀÀdöstÀ maantiekÀyttöön tarkoitetuille ajoneuvoille. NÀmÀ ovat kyberturvallisuuteen R155 ja ohjelmistopÀivitykseen R156 liittyvÀt sÀÀdökset, joista jÀlkimmÀinen vaikuttaa myös maatalousajoneuvojen valmistajiin. Myös uusi International Standardization Organization (ISO) ja Society of Automotive Engineers (SAE) organisaatioiden yhdessÀ tekemÀ kyberturvallisuuden suunnittelustandardi muuttaa organisaatioiden riskienhallintaa. Ajoneuvovalmistajien on pohdittava turvallisuutta aivan uudesta nÀkökulmasta; kuinka pienentÀÀ ajoneuvojen kyberturvallisuusriskiÀ muille tienkÀyttÀjille. TÀmÀ opinnÀytetyö tutkii kyberturvallisuuteen liittyviÀ autoalan sÀÀdöksiÀ ja standardeja sekÀ kyberturvallisuuden johtamisprosesseja. Työn empiirinen osa kÀsittelee maatalousajonevoihin erikoistunutta yritystÀ. Empiirisen osan metodologia on suunnittelutiede, joka soveltuu uusien artefaktien ja ratkaisujen kehittÀmiseen. Tutkimuksen empiirisessÀ osassa kehitettiin uusi arviointityökalu, jolla sidosryhmÀt voivat kerÀtÀ tietoja organisaation valmiuksista ajoneuvojen kyberturvallisuuden hallintaan. TÀmÀ opinnÀytetyö tarjoaa pohjatietoa kyberturvallisuuden periaatteista ja kyberturvallisuuden hallinnan prosesseista sekÀ yleiskatsauksen nykyiseen autoalan sÀÀntelyyn ja kyberturvallisuuteen liittyviin ajoneuvostandardeihin
The improvement of 5G massive MIMO antenna array port-to-port isolation
Abstract. In this thesis, the phenomenon of mutual coupling in 5G mMIMO base station antenna array is studied and a solution to improve port-to-port isolation is proposed. Mutual coupling occurs when antennas are placed close to each other in modern base station antenna arrays. Basically, it causes other antennas to absorb part of the antennaâs radiated energy or rescatter a portion of the incident energy in various directions, allowing them to act as secondary transmitters. The absorbed energy by other antenna changes an array radiation pattern, array manifold and radiators input impedance changed. This is not a desirable phenomenon because the other antennasâ absorbed energy is not radiated as designed and change in input impedance causes mismatches. So,mutual coupling lowers antenna array efficiency and performance in transmitter and receiver.
The initial antenna array design in this work is Nokiaâs own model, operating in the frequency band of 3.3â3.8 GHz. It is already in the production and deployment phase to the field for customers. The aim of the work was to improve port-to-port isolation from -18.74 dB to -30 dB while maintaining all other design parameters for matching and radiation properties. To do this, antenna mutual coupling is studied and simulated in the original design with the electromagnetic simulation tool Ansys HFSS. The simulation cases are divided into smaller models, based on how coupling occurs in the design. Root causes for restricting the isolation performance are observed and a proposed method for improved port-to-port isolation is illustrated. To verify the correct radiation performance for the proposed method, radiation results are post-processed with MATLAB. Finally, the results are analysed based on the base station antenna standards and compared to the initial design. This thesis provided a 2.84 dB for port-to-port isolation improvement while meeting all other design specifications.Portista porttiin vĂ€lisen isolaation parantaminen 5G mMIMO antenniryhmĂ€ssĂ€ . TiivistelmĂ€. TĂ€ssĂ€ diplomityössĂ€ tutkitaan antennien vĂ€listĂ€ keskinĂ€istĂ€ kytkeytymistĂ€ 5G mMIMO tukiasema-antenniryhmĂ€ssĂ€ ja esitellÀÀn ratkaisu portista porttiin vĂ€lisen isolaation parantamiseksi. Antennien vĂ€linen keskinĂ€inen kytkeytyminen tapahtuu, kun ne ovat lĂ€hellĂ€ toisiaan moderneissa tukiasema-antenniryhmissĂ€. Sen takia toiset antennit absorboivat osan yhden antennin lĂ€hettĂ€mĂ€stĂ€ energiasta tai uudelleen sirottavat sen useisiin suuntiin aiheuttaen niiden toimimisen sekundÀÀrisinĂ€ lĂ€hettiminĂ€. Toisten antennien absorboima energia muuttaa niiden sĂ€teilykuvioita, jĂ€nnitteitĂ€ ja tuloimpedanssia. TĂ€mĂ€ ei ole toivottu ilmiö, koska toisten antennien absorboima energia ei ole lĂ€hetetty alkuperĂ€isestĂ€ sĂ€teilijĂ€stĂ€ kuten on suunniteltu, ja tuloimpedanssin muutos aiheuttaa antenneihin epĂ€sovitusta. Antennien vĂ€linen kytkeytyminen siis huonontaa antenniryhmĂ€n tehokkuutta ja suorituskykyĂ€ sekĂ€ lĂ€hettimessĂ€ ettĂ€ vastaanottimessa.
Työn alkuperĂ€inen antenniryhmĂ€malli on Nokian kehittĂ€mĂ€ ja toimii 3.3â3.8 GHz taajuuskaistalla. Se on jo tuotanto- ja kĂ€yttöönottovaiheessa kentĂ€llĂ€ asiakkaille. TĂ€mĂ€n työn tavoite on parantaa portista porttiin vĂ€listĂ€ isolaatiota -18.74 dB:stĂ€ -30 dB:iinsĂ€ilyttĂ€en samalla kaikki muut suunnitteluparametrit sovitukselle ja sĂ€teilyominaisuuksille. TĂ€mĂ€n saavuttamiseksi antennien keskinĂ€istĂ€ kytkentÀÀ tutkitaan ja simuloidaan alkuperĂ€isessĂ€ mallissa sĂ€hkömagneettisella simulointityökalulla, Ansys HFSS:llĂ€. Simulaatiotapaukset on jaettu pienempiin osiin sen mukaan, miten antennien vĂ€linen keskinĂ€iskytkentĂ€ tapahtuu alkuperĂ€isessĂ€ mallissa. Isolaation suorituskyvyn rajoittamisen juurisyyt esitellÀÀn ja ehdotettu menetelmĂ€ porttien vĂ€lisen eristyksen parantamiseksi mallinnetaan ja simuloidaan. Ehdotetun menetelmĂ€n sĂ€teilyominaisuuksien tarkistamiseksi tulokset jĂ€lkikĂ€sitellÀÀn MATLAB ohjelmistolla. Lopuksi sĂ€teilytuloksia analysoidaan tukiaseman antennistandardien perusteella ja verrataan alkuperĂ€iseen malliin. TĂ€ssĂ€ työssĂ€ saavutetaan 2.84 dB:n parannus portista porttiin isolaatioon samalla saavuttaen kaikki muut suunnitteluspesifikaatiot
Effect of temperature-dependent eta/s on flow anisotropies
We investigate the effects of a temperature-dependent shear viscosity over
entropy density ratio eta/s on the flow anisotropy coefficients v_2 and v_4 in
ultrarelativistic heavy-ion collisions at RHIC and LHC. We find that v_4 is
more sensitive to the viscosity at low temperatures than v_2. At RHIC v_2 is
mostly affected by the viscosity around the phase transition, but the larger
the collision energy, the more the quark-gluon plasma viscosity affects v_2.Comment: 6 pages, 11 figures, parallel talk in Strangeness in Quark Matter
conference, Cracow, Sept 201
Crop Supply Response under Risk: Impacts of Emerging Issues on Southeastern U.S. Agriculture
In this paper we consider factors that affect both crop prices and yields in order to examine supply responses of major crops in the Southeast. Due to the variable nature of crop production in the Southeast, previous studies that ignore price and yield risk may fail to capture one of the salient features of the regionâs agriculture. Our results indicate supply elasticity values for corn, cotton, and soybeans of approximately 0.670, 0.506, and 0.195, respectively. Compared with the results of studies in other regions, corn and cotton acres respond more to price changes and soybean acres respond less to price changes.acreage supply, crop supply response model, risk analysis, Southeast U.S. agriculture, Crop Production/Industries, Production Economics, Q12, Q13, Q16,
P 093 - Comparison of three bipedal tasks to quantify contribution of proprioception to postural stability in healthy children and adolescents : Helsinki University Central Hospital, HUH Children and Adolescents
Static postural sway can be quantified as variation in body's center of force (COF) position across time using a plantar pressure plate. We aimed to compare capability of three clinically feasible bipedal tasks to extract the contribution of proprioception to postural stability. We measured the postural sway of 24 healthy volunteers (age range 10.2â17.6 years) with a plantar-pressure plate with three different standing tasks: (1) normal standing, (2) normal standing on soft foam, and (3) feet together standing. Each task was repeated eyes closed to emphasize the contribution of proprioception on maintaining the postural stability. The effect of closing the eyes varied among the tasks, and was greatest in the feet together standing task, possibly due to greater proprioceptive demands in the more difficult tasks. It appears that standing feet together is a potential task for quantifying contribution of proprioception to postural stability. © 2018 Elsevier B.V.Non peer reviewe
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