Results 21 to 30 of about 766,611 (315)
Multi-Frequency VLBI observations of 3C390.3 [PDF]
Symposium - International Astronomical Union, 1996 We have mapped the broad line radio galaxy 3C390.3 at 1.3, 6, and 18 cm wavelengths with resolutions ranging from 0.2 to 2.7 mas. Our new 6 cm image is consistent with a stationary bright region located 4 to 5 mas from the core and motion of the other features with apparent velocities of 0.4 to 0.7 mas/yr.
E. Preuss, W. Alef, K. I. Kellermann
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Remote Sensing, 2023 In the framework of maritime surveillance, vessel detection techniques based on spaceborne synthetic aperture radar (SAR) images have promoted extensive applications for the effective understanding of unlawful activities at sea.
Roberto Del Prete +2 more
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Journal of Marine Science and Engineering, 2023 This study was conducted to investigate the acoustic characteristics of largehead hairtails (Trichiurus japonicus) in the Southern Sea of South Korea from April 2022, using 18, 38, 70, 120, and 200 kHz split-beam echosounders.
Hyungbeen Lee +3 more
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Remote Sensing, 2018 To reduce the floor space of receiving antenna arrays, the Radio Ocean Remote SEnsing (RORSE) laboratory of Wuhan University developed a circular receiving array for a multi-frequency high frequency (MHF) radar system in 2014, consisting of seven ...
Chen Zhao +5 more
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Remote Sensing, 2023 Previous studies of GNSS-IR mainly focused on the legacy L1C signal; the potential of modernized signals (L2C and L5Q) has not yet been fully exploited.
Jintao Lei, Wenhao Li, Shengkai Zhang
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A multi-frequency RF photocathode gun [PDF]
AIP Conference Proceedings, 2012 The concept of a photocathode injection gun driven by several harmonically related phase-locked RF sources is considered. This concept is aimed at providing electron bunches with parameters as follows: charge/bunch ≥1 nC, bunch energy 5-10 MeV, bunch width 20-40 ps, and fundamental frequency = 1.3 GHz.
Kuzikova, S. V. +4 more
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GNSS Signals Acquisition and Tracking in Unfavorable Environment [PDF]
Radioengineering, 2018 In this paper, we propose a method based on applying specific transformations to the Global Navigation Satellite System (GNSS) signals received in unfavorable environment.
S. Chebir +4 more
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A Novel VLSI Architecture for Multi-Constellation and Multi-Frequency GNSS Acquisition Engine
IEEE Access, 2019 This paper proposes a novel VLSI architecture of GNSS acquisition engine based on short-time correlation combined with an FFT scheme. The architecture supports multi-constellation systems and multi-frequency satellite signals flexibly by the manner of ...
Yuheng Yang, Xiaohui Ba, Jie Chen
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Topological lattice using multi-frequency radiation [PDF]
New Journal of Physics, 2018 We describe a novel technique for creating an artificial magnetic field for ultra-cold atoms using a periodically pulsed pair of counter propagating Raman lasers that drive transitions between a pair of internal atomic spin states: a multi-frequency coupling term.
Andrijauskas, Tomas +2 more
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Community detection in multi-frequency EEG networks
Scientific Reports, 2023 AbstractFunctional connectivity networks of the human brain are commonly studied using tools from complex network theory. Existing methods focus on functional connectivity within a single frequency band. However, it is well-known that higher order brain functions rely on the integration of information across oscillations at different frequencies ...
Abdullah Karaaslanli +3 more
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