Results 31 to 40 of about 54,093 (284)

A numerical study of an inline oscillating cylinder in a free stream [PDF]

, 2011
Simulations of a cylinder undergoing externally controlled sinusoidal oscillations in the free stream direction have been performed. The frequency of oscillation was kept equal to the vortex shedding frequency from a fixed cylinder, while the amplitude ...
Leontini, Justin S., Justin S. Leontini, Mark C. Thompson, Lo Jacono, David, Thompson, Mark C., David Lo Jacono   +5 more
core   +1 more source

Frequency Dynamic Characteristic Analysis of Ultra-Low Frequency Oscillation and Multi-Machine GPSS Parameter Tuning Method [PDF]

Dianli jianshe
[Objective] The growing concern over frequency stability is attributed to the decreasing overall inertia of power systems. To improve the analysis of frequency stability and performance of modern power systems， a frequency dynamic characteristic analysis
ZENG Pijiang, XU Hao, YE Pengju, ZHENG Chao, SAI Xiangyu, CHEN Gang, ZHAO Yong, JIANG Chuyang, GAN Deqiang
doaj   +1 more source

Ultra-Narrow Bandwidth Microwave Photonic Filter Implemented by Single Longitudinal Mode Parity Time Symmetry Brillouin Fiber Laser

Micromachines, 2023
In this paper, a novel microwave photonic filter (MPF) based on a single longitudinal mode Brillouin laser achieved by parity time (PT) symmetry mode selection is proposed, and its unparalleled ultra-narrow bandwidth as low as to sub-kHz together with ...
Jiaxin Hou, Yajun You, Yuan Liu, Kai Jiang, Xuefeng Han, Wenjun He, Wenping Geng, Yi Liu, Xiujian Chou   +8 more
doaj   +1 more source

Magnetopause surface oscillation frequencies at different solar wind conditions [PDF]

Annales Geophysicae, 2009
Statistical analyses of the magnetopause (MP) motion observed by THEMIS suggested that the MP oscillates preferably at some prominent (sometimes called "magic") frequencies, which were found to stand out also in ground-based and ionospheric ...
F. Plaschke, K.-H. Glassmeier, K.-H. Glassmeier, D. G. Sibeck, H. U. Auster, O. D. Constantinescu, V. Angelopoulos, W. Magnes   +7 more
doaj   +1 more source

Multiple DC Modulation Coordination Strategies Based on Transient Energy Function and Deep Deterministic Policy Gradient Algorithm

Applied Sciences
Ultra-low-frequency oscillation (ULFO) is a new problem of frequency stability in asynchronous network back-end power networks. The negative damping provided by hydropower units is the direct cause of ultra-low-frequency oscillation, and DC modulation is
Chao Xing, Mingqun Liu, Junzhen Peng, Xueke Wang, Yuhong Wang, Zongsheng Zheng, Shilin Gao, Jianquan Liao   +7 more
doaj   +1 more source

A pilot study of the impact of high-frequency chest wall oscillation in chronic obstructive pulmonary disease patients with mucus hypersecretion

, 2011
Indranil Chakravorty1, Kamaljit Chahal2, Gillian Austin21St George's Hospital, London, 2East and North Hertfordshire NHS Trust, Lister Hospital and Primary Care Trust, Stevenage, Hertfordshire, UKIntroduction: Chronic obstructive pulmonary ...
Chahal, K, Chakravorty, I, Chahal K, null Chahal, Austin G, Chakravorty I, Indranil Chakravorty, Austin, G, null Austin   +8 more
core   +1 more source

Modelling and analysis of frequency-responsive wind turbine involved in power system ultra-low frequency oscillation [PDF]

, 2022
This paper presents a dynamic analysis for ultra-low frequency oscillations (ultra-LFOs) observed in the wind-hydropower hybrid systems. In such systems, DFIG wind turbines (WTs) are required to be frequency-responsive with providing the inertia and ...
Sun, Li, Zhao, Xiaowei
core   +1 more source

EEMD and bidimensional RLS to suppress physiological interference for heterogeneous distribution in fNIRS study [PDF]

Journal of Innovative Optical Health Sciences, 2018
Near-infrared spectroscopy (NIRS) can provide the hemodynamics information based on the hemoglobin concentration representing the blood oxygen metabolism of the cerebral cortical, which can be deployed for the cerebral function study. However, NIRS-based
Yan Zhang, Dan Liu, Qisong Wang, Xin Liu, Chunling Yang, Jinwei Sun, Jingyang Lu, Peter Rolfe   +7 more
doaj   +1 more source

Front-End Module of 18–40 GHz Ultra-Wideband Receiver for Electronic Warfare System [PDF]

Journal of the Korean Institute of Electromagnetic Engineering and Science, 2018
In this study, we propose an approach for the design and satisfy the requirements of the fabrication of a small, lightweight, reliable, and stable ultra-wideband receiver for millimeter-wave bands and the contents of the approach.
Yuseok Jeon, Sungil Bang
doaj   +1 more source

Design and analysis strategies for robust microbiome ageing research

FEBS Letters, EarlyView.
The gut microbiome changes with age and associates with age‐related morbidity and mortality, establishing it as a potential biomarker and intervention target for ageing. Realising this potential requires methodological rigour, yet distinguishing biological signals from methodological artefacts remains challenging across cohorts. This review provides an
Mark Olenik, İsmail Güderer, Yi Wang, Tayyaba Alvi, Prasoon Pandey, Handan Melike Dönertaş   +5 more
wiley   +1 more source