Results 11 to 20 of about 44,850 (204)
Respiratory impedance measured using impulse oscillometry in a healthy urban population [PDF]
ERJ Open Research, 2021 This study derives normative prediction equations for respiratory impedance in a healthy asymptomatic urban population using an impulse oscillation system (IOS).
Kenneth I. Berger +9 more
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Tower impulse grounding resistance measurement based on multiple frequency impedance
IET Generation, Transmission & Distribution, 2023 Tower impulse grounding resistance is important for judging the lightning protection performance of transmission lines. Therefore, it is significant to accurately measure the tower impulse grounding resistance. Existing measurement methods mainly contain
Yihua Dan +5 more
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Transient impedance of grounding system with impulse superimposed sinewave
ENP Engineering Science Journal, 2021 Investigating the transient performance of grounding systems subject to lightning (impulse or impulse superimposed sinewave) is valuable for protecting the power system and maintaining the system operation.
Sherif Ghoneim +2 more
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Respiratory mechanics: modelling, measurement and clinical applications—a review [PDF]
BioMedical Engineering OnLineThe mechanical properties of the airways significantly impact respiration, and estimating respiratory mechanics provides important insights for diagnosing and monitoring respiratory diseases, such as asthma and chronic obstructive pulmonary disease. Here,
Anuva Chowdhury, Mathias Baumert
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Modeling of different tower grounding systems using hybrid continuous circuit-trapezoidal integration method [PDF]
Serbian Journal of Electrical Engineering, 2021 In order to protect the transmission lines against lightning strikes, it is important to investigate the tower grounding system. In this paper, a recent method called hybrid continuous circuit-trapezoidal integration method is used to calculate ...
Asadpourahmadchali Mohammadbagher +2 more
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Energy Reports, 2022 This research assessed the transmission tower’s surge impedance before and after paralleling the overhead ground wire (OHGW) made of twisted galvanized steel cable from topmost of the transmission tower to the tower ground footage.
Chakkri Satchathampitak +2 more
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Evaluation principle and method of horizontal grounding electrode based on time‐varying impedance
IET Science, Measurement & Technology, 2021 The length of the horizontal grounding electrode is usually extended to decrease the impulse grounding resistance. In this paper, the mechanism for influencing the effective length is revealed by studying the dispersal process of a horizontal electrode ...
Xiaobin Cao +5 more
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On the Characterisations of the Impulse Breakdown in High Resistivity Soils by Field Testing
Energies, 2021 This paper presents experimental results of high-current impulse tests on six ground electrode configurations. A high impulse current generator is employed to inject different magnitudes of current into these rod electrodes, under both positive and ...
Abdul Wali Abdul Ali +1 more
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IET Generation, Transmission & Distribution, 2023 The impulse grounding impedance of tower grounding device is one of the important factors in the lightning protection evaluation of transmission line. The impulse characteristic test of the actual tower grounding device under lightning was rarely carried
Yi Zhang +7 more
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Review: Factors Affecting the Performance of Ground Electrodes under High Impulse Currents
Energies, 2023 Most studies have observed that the impedance values of ground electrodes under high impulse conditions (Zimp) are lower than the resistance values under steady-state conditions (RDC).
Normiza Mohamad Nor
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