Results 21 to 30 of about 114,029 (207)
Metrology and Measurement Systems, 2020 The possibilities to improve values of the satellite orbit elements by employing the pseudo-ranges and differences of carrier phase frequencies measured at many reference GPS stations are analysed. An improvement of orbit ephemeris is achieved by solving
Skeivalas Jonas +3 more
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Optimal nonlinear filtering of MPSK signals in the presence of a Doppler frequency shift
Российский технологический журнал, 2022 Objectives. Phase-shift keyed (PSK) signals are widely used in many telecommunication, communication, and cellular information transmission systems. Phase-shift keying provides a higher noise immunity than amplitude and frequency modulations do.
G. V. Kulikov, T. T. Do, R. R. Usmanov
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Guidelines for ultrasound examination in ophthalmology. Part III: Color Doppler ultrasonography
Journal of Ultrasonography, 2019 The aim of this article was to present the possibilities of use and application of color-coded Doppler ultrasonography in the diagnosis of various diseases of the eyeball and orbit which result from vascular disorders. Color-coded Doppler ultrasonography
Monika Modrzejewska
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Nihon Kikai Gakkai ronbunshu, 2021 The variation of the noise metrics of a group of sound sources due to its movement at a constant velocity along a straight track is discussed in the paper.
Yusuke MAKINO, Yasushi TAKANO
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High-sensitive acquisition method of GPS signal based on iridium assistance
The Journal of Engineering, 2019 Global positioning system (GPS) signal is severely attenuated in indoor, urban, and forest environments. To capture weak GPS signal, long-time coherent integration and non-coherent integration are used to increase signal to noise ratio (SNR).
Hao Zihuan, Zhang Lei
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Dizhen xuebao, 2018 本文介绍了全球主要地震机构对2008年5月12日汶川地震参数的速报和修订情况，分析了美国地质调查局国家地震信息中心测定的面波震级。通过对比198个全球地震台站测定的面波震级和面波周期，得出如下结论：测定面波震级偏大的台站主要分布在震中的东北方向，测定面波震级偏小的台站主要分布在震中的西南和东南方向，面波周期偏小的台站主要分布在震中东北方向。由于此次地震破裂方向是以北东向单侧破裂为主，且地震多普勒效应导致震中东北方向振动加强，因此该方向上的面波震级偏大，地震烈度衰减慢；而震中西南方向的振动减弱 ...
Ruifeng Liu, Liye Zou, Liwen Zhang
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地震科学进展, 2021 A magnitude M7.8 earthquake struck Kermadec Island，New Zealand on March 5，2021. In this study we determined surface wave magnitude using 692 stations from USGS global networks and 112 stations from China global earthquake monitoring system，then analyzed ...
Wenze Deng
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Measurement of nonlinear and Doppler distortion in Distributed Mode Loudspeakers [PDF]
International Journal of Electronics and TelecommunicationsDistributed Mode Loudspeakers (DMLs), as other electroacoustic transducers with electrodynamic excitation, are susceptible to the occurrence of nonlinear distortion. The literature on nonlinear distortion in DMLs is scarce.
Karol Czesak, Piotr Kleczkowski
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Performance analysis of DSSS- and CSS-based physical layer for IoT transmission over LEO satellites
ETRI Journal, 2022 To determine a suitable waveform for Internet of Things (IoT) transmission over low-Earth orbit (LEO) satellites, this paper reports the results of a performance comparison between chirp spread spectrum (CSS)-based LoRa and direct sequence spread ...
Sooyeob Jung +5 more
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International Archives of Otorhinolaryngology, 2013 Introduction Technological advances have provided a large variety of instruments to view the swallowing event, aiding in the evaluation, diagnosis, and monitoring of disturbances.
Hellen Nataly Correia Lagos +4 more
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