Exploració per autor "Liu, Qi"

Ara es mostren els items 1-10 de 10

    • A New way of estimating the spatial and temporal components of the vertical total electron content gradient based on UPC-IonSAT global ionosphere maps 

      Liu, Qi; Hernández Pajares, Manuel; Yang, Heng; Monte Moreno, Enrique; García Rigo, Alberto; Lyu, Haixia; Olivares Pulido, Germán; Orús Pérez, Raul (2022-02)
      Article
      Accés obert
      The determination of the ionospheric perturbation degree is essential to describe the ionosphere state for space weather monitoring. A new method for estimating the spatial and temporal components of the Vertical Total ...

    • Converting brownmillerite to alternate layers of Oxygen-deficient and conductive nano-sheets with enhanced thermoelectric properties 

      Hu, Songbai; Han, Wenqiao; Li, Xiaowen; Ye, Mao; Lu, Yao; Jin, Cai; Liu, Qi; Wang, Junling; He, Jiaqing; Cazorla Silva, Claudio; Zhu, Yuanmin; Chen, Lang (John Wiley & sons, 2022-06-11)
      Article
      Accés obert
      Introducing large oxygen deficiencies while retaining low resistivity is important for enhancing the overall thermoelectric properties in 3d transition-metal oxides. In this study, a new synthesis route to reconstruct the ...

    • GNSS solar astronomy in real-time during more than one solar cycle 

      Hernández Pajares, Manuel; García Rigo, Alberto; Monte Moreno, Enrique; Liu, Qi; Roma Dollase, David; Yang, Heng; Beniguel, Yannick; Moreno Borrás, David; Fors Aldrich, Octavi; Lyu, Haixia; Orús Pérez, Raul; Ventura Traveset, Javier (Elsevier, 2023-12-09)
      Article
      Accés obert
      This work presents a summary of the continuous non-stop (hereinafter 24/7) real-time measurement and warning system for EUV solar activity, which is based on worldwide multifrequency Global Navigation Satellite Systems ...

    • GNSS-based global ionospheric maps : real-time combination, time resolution and applications on space weather monitoring 

      Liu, Qi (Universitat Politècnica de Catalunya, 2022-04-14)
      Tesi
      Accés obert
      The research of this paper-based dissertation is focused on the Global Ionospheric Maps (GIMs) based on Global Navigation Satellite System (GNSS) including real-time combination, validation, time resolution and applications. ...

    • High-conductive protonated layered oxides from H2O vapor-annealed brownmillerites 

      Hu, Songbai; Zhu, Yuanmin; Han, Wenqiao; Li, Xiaowen; Ji, Yanjiang; Ye, Mao; Jin, Cai; Liu, Qi; Hu, Sixia; Wang, Jiaou; Wang, Junling; He, Jiaqing; Cazorla Silva, Claudio; Chen, Lang (2021-12-02)
      Article
      Accés obert
      Protonated 3d transition-metal oxides often display low electronic conduction, which hampers their application in electric, magnetic, thermoelectric, and catalytic fields. Electronic conduction can be enhanced by co-inserting ...

    • Influence of temporal resolution on the performance of global ionospheric maps 

      Liu, Qi; Hernández Pajares, Manuel; Lyu, Haixia; Goss, Andreas (2021-03)
      Article
      Accés obert
      Global ionosphere maps (GIM) computed from dual-frequency GNSS measurements have been widely used for monitoring ionosphere as well as providing ionospheric corrections in Space Geodesy since 1998. This work focuses on a ...

    • Ionospheric storm scale index based on high time resolution UPC-IonSAT global ionospheric maps (IsUG) 

      Liu, Qi; Hernández Pajares, Manuel; Lyu, Haixia; Nishioka, Michi; Yang, Heng; Monte Moreno, Enrique; Gulyaeva, Tamara L.; Beniguel, Yannick; Wilken, Volker; Olivares Pulido, Germán; Orús Pérez, Raul (2021-11)
      Article
      Accés obert
      The ionospheric storms have adverse effects on the radio communications, satellite communications and also the Global Navigation Satellite Systems (GNSS) application. A new Ionospheric storm Scale from Universitat Politècnica ...

    • Systematic detection of anomalous ionospheric perturbations above LEOs from GNSS POD Data including possible tsunami signatures 

      Yang, Heng; Hernández Pajares, Manuel; Jarmolowski, Wojciech; Wielgosz, Pawel; Vadas, Sharon L.; Colombo, Oscar L.; Monte Moreno, Enrique; García Rigo, Alberto; Graffigna, Victoria; Krypiak-Gregorczyk, Anna; Milanowska, Beata; Bofill Soliguer, Pablo; Olivares Pulido, Germán; Liu, Qi; Haagmans, Roger (Institute of Electrical and Electronics Engineers (IEEE), 2022-06-13)
      Article
      Accés obert
      In this article, we show the capability of a global navigation satellite system (GNSS) precise orbit determination (POD) low Earth orbit (LEO) data to detect anomalous ionospheric disturbances in the spectral range of the ...

    • The cooperative IGS RT-GIMs: a reliable estimation of the global ionospheric electron content distribution in real time 

      Liu, Qi; Hernández Pajares, Manuel; Yang, Heng; Monte Moreno, Enrique; Roma Dollase, David; García Rigo, Alberto; Li, Zishen; Wang, Ningbo; Laurichesse, Denis; Zhao, Q.; Wübbena, Gerhard; Krankowski, Andrzej; Ghoddousi Fard, Reza; Blot, Alexis; Zhang, Qiang (2021-09-23)
      Article
      Accés obert
      The Real-Time Working Group (RTWG) of the International GNSS Service (IGS) is dedicated to providing high-quality data and high-accuracy products for Global Navigation Satellite System (GNSS) positioning, navigation, ...

    • Validation of global ionospheric models using long-term observations of pulsar Faraday rotation with the LOFAR radio telescope 

      Porayko, Nataliya; Mevius, Maaijke; Hernández Pajares, Manuel; Tiburzi, Caterina; Olivares Pulido, Germán; Liu, Qi; Verbiest, Joris; Künsemöller, Jörn; Krishnakumar, Moochickal Ambalappat; Bak Nielsen, Ann Sofie; Brüggen, Marcus; Graffigna, Victoria; Dettmar, Ralf Jürgen; Kramer, Michael (Springer Nature, 2023-12-13)
      Article
      Accés obert
      Broad band pulsar radiation can be effectively used to monitor the properties of the magneto-ionic media through which it propagates. Faraday rotation calculated from polarised pulsar observations provides an integrated ...