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Osuva on Vaasan yliopiston avoin julkaisuarkisto. Osuva sisältää Vaasan yliopiston omat julkaisut, opinnäytteet ja tieteellisten artikkeleiden rinnakkaistallenteet. Osuvaan sisältyy julkaisujen viitetietoja, tiivistelmiä ja kokotekstejä. Sähköisten arkistokokoelmien sisältö ei ole luettavissa verkossa.

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Viimeksi tallennetut

  • Massive MIMO Beam ID-Based Positioning Method With Low Earth Orbit Satellite Mega Constellations
    Elsanhoury, Mahmoud; Koljonen, Janne; Prol, Fabricio S.; Elmusrati, Mohammed S.; Kuusniemi, Heidi (IEEE, 2025)
    Artikkeli
    The growth of satellite-based positioning methods has revolutionized global navigation by providing reliable geolocation capabilities. However, traditional Global Navigation Satellite Systems (GNSS) are increasingly vulnerable to threats like jamming, spoofing, and interception, undermining their reliability in critical applications such as in-flight navigation and emergency services. To address these challenges, Low Earth Orbit (LEO) satellite constellations have emerged as a promising complement to GNSS infrastructure. LEO satellites, orbiting at lower altitudes with higher density, offer improved signal availability, reduced degradation, and better reception on Earth. This paper presents a LEO satellite-based positioning method via massive multiple-input multiple-output (mMIMO) beamforming antennas. The proposed technique not only mitigates GNSS vulnerabilities but also introduces a passive sensing mechanism that facilitates positioning without complex timing synchronization, improving resilience in jamming-prone environments. By utilizing LEO satellite beam identifiers as geographic pointers, our method enables precise positioning through LEO satellite ephemeris and beam pattern data. We validate this beam-based method through simulations, LEO constellation data, vehicular drive-test datasets, and probabilistic positioning models. Positioning results from the first dataset show a mean absolute error (MAE) of 9.15 meters and a 95th percentile error (p95%) of 19.07 meters when combining LEO satellite data with inertial motion data from a moving vehicle. Meanwhile, GNSS accuracy was MAE = 26.6 meters and p95% = 56.6 meters. The second dataset showed consistent results with accuracy improvements in MAE from 18.55 to 9.42 meters, RMSE from 22.24 to 12.05 meters, and p95% from 36.38 to 21.18 meters, compared to GNSS. These findings highlight the potential of LEO satellite positioning to improve accuracy and reliability in challenging environments, with implications for critical applications such as remote sensing, emergency response, search and rescue, and situational awareness.
  • The geopolitics of space technology in a geoeconomic context: Strategic importance and global implications
    Punnala, Santeri; Punnala, Mikko; Baber, William W.; Ojala, Arto; Munoz, J. Mark (toim.) (Routledge, 2026)
    Artikkeli
    ABSTRACT Space technology has emerged as a critical component of geopolitical strategy, influencing global power dynamics and international relations. This chapter explores the historical development, strategic importance, and geopolitical implications of space technology. By examining the roles of major players and the challenges of space governance, it provides a comprehensive analysis of how space technology now shapes global power structures. Unlike during the Cold War era, space is not a two-party race. Rather, blocs appear to be emerging, with long-term ramifications for the participants. Commercialisation is an important driver alongside military applications; indeed, dual-use technologies and systems are likely to be the norm. The chapter concludes with insights into future trends and their potential impact on geopolitics, offering recommendations for policymakers and stakeholders to navigate this evolving landscape.
  • Literature Review of the ETL and ELT Data Integration Pipelines
    Junka, Jeremi (2026-02-27)
    Kandidaatintutkielma
    This is a literature review on ETL (Extract-Transform-Load) and ELT (Extract-Load-Transform) data integration pipelines. The literature review focuses on how the pipelines operate and how they can be optimized from a performance viewpoint. Both ETL and ELT pipelines are used for the same goal, but the execution of the processes differ significantly. In this study three main phases that comprise both types of pipeline models are focused on. In ETL pipelines the transformation process is completed prior to loading the data into the target system. With ELT pipelines the transformation process is executed after loading the data into the target system. In this literature review the optimization of these phases is studied. This study also compares the suitability of the two pipeline models in different architectures.Tämä tutkielma on kirjallisuuskatsaus ETL (Extract-Transform-Load)- ja ELT (Extract-Load-Transform) -dataintegraatioprosesseista. Kirjallisuuskatsaus keskittyy prosesseihin ja niiden toimintaan ja siihen, miten niitä voidaan optimoida suorituskyvyn näkökulmasta. Sekä ETL- että ELT-prosesseja käytetään samaan tarkoitukseen, mutta prosessien toteutus eroaa merkittävästi toisistaan. ETL-prosessoinnissa muunnosprosessi suoritetaan ennen datan lataamista kohdejärjestelmään, kun taas ELT-prosessoinnissa muunnosprosessi suoritetaan datan kohdejärjestelmään lataamisen jälkeen. Tässä tutkielmassa keskitytään kolmeen päävaiheeseen, jotka esiintyvät molemmissa dataintegraatioputkimalleissa. Tässä kirjallisuuskatsauksessa tutkitaan näiden kolmen päävaiheiden optimointia. Tutkielmassa vertaillaan myös näiden kahden prosessointiprosessimallin soveltuvuutta eri arkkitehtuureihin.
  • Upgrading to Escape the Low Value-Added Trap in Global Value Chains: The Mediating Role of Strategic Learning Capability
    Islam, Mohammad Tarikul; Polonsky, Michael Jay; Khan, Zaheer (Springer, 2026)
    Artikkeli
    Combining both internalizing and externalizing logics in governance has been argued to enhance the efficiency of global value chain (GVCs); however, its implication for suppliers’ upgrading remains contested. The fragmentation of value chain activities has increased interdependencies between multinational enterprises (MNEs) and suppliers in developing economy that can be managed through effective governance strategies. While previous studies often claim that MNEs’ governance strategies determine suppliers’ upgrading potential in GVCs, the findings have been inconclusive, prompting calls for more research on this relationship. In this study, we draw from resource dependence and relational exchange theories to explore how buyer–supplier relationships manage external dependencies in GVCs, and the implications of these dependencies for supplier upgrading and performance. We argue that socially embedded relational governance when interacting with relationship length facilitates strategic learning capability, which in turn influences both low and high value-added upgrading of suppliers as well as their performance. Our findings reveal that strategic learning capability serves as the mechanism through which the benefits of a socially embedded relational governance are transformed into suppliers’ upgrading. Moreover, high value-added upgrading has a stronger impact on suppliers’ performance than low value-added upgrading. These findings suggest that strategies for managing external dependencies are influenced not solely by external and internal factors but rather their interaction. We draw implications of these findings for research and practice.
  • Institutional complexity of public sector reform: conflicts and dynamics in local–regional cooperation
    Rossi, Paula; Paananen, Henna; Jäntti, Anni; Jalonen, Harri; Haveri, Arto (Taylor & Francis, 2026)
    Artikkeli
    Tämän artikkelin keskiössä ovat julkiset palvelureformit, joita tarkastellaan institutionaalisen kompleksisuuden teoreettisen viitekehyksen kautta. Tämä integroiva viitekehys kokoaa yhteen julkisen johtamisen ja hallinnan tieteenalan konflikteihin monitasoisissa palvelujärjestelmissä liittyvää tutkimusta. Tarkastelemme sote-uudistuksessa yhteistyötä tekevien toimijoiden välisen yhteistyön taustalla vaikuttavaa dynamiikkaa ja sen tahattomia seurauksia paikallisyhteisöille. Tutkimuksen aineistona on suomalaisten kuntien sekä hyvinvointialueiden välistä yhteistyötä käsittelevä monipuolinen haastattelu- sekä kyselyaineisto, joka on analysoitu käyttäen konflikteja analyyttisena työkaluna. Tulokset paljastavat paikallisten (kunnat) ja alueellisten (hyvinvointialueet) toimijoiden yhteistyön dynamiikan monitasoisissa hallintojärjestelmissä tuottaen uutta tietoa siitä, miten tämä dynamiikka vaikuttaa yhteistyössä toimivien toimijoiden mahdollisuuksiin edistää yhteisöpohjaisia tuloksia paikallisyhteisöille ja niiden kansalaisille luotuna arvona. Lopuksi tarkastelemme tuloksia institutionaalisen kompleksisuuden viitekehyksen kautta.