Results 281 to 290 of about 48,016 (315)
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Reduction of stent artifacts using high-frequency harmonic ultrasound imaging
Ultrasound in Medicine & Biology, 2005Tissue harmonic imaging (THI) has been shown to improve medical ultrasound (US) image quality in the frequency range from 2 to 10 MHz and might, therefore, also be advantageous in high-frequency US applications, like US biomicroscopy and intravascular US (IVUS).
Frijlink, ME (Martijn) +2 more
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Parametric generation of high-frequency harmonics in semiconductor superlattices
Semiconductors, 2012The behavior of the semiconductor superlattice in a biharmonic quasi-static electric field containing a static component is studied. Analytical expressions for the high-frequency response are derived. The possibility of the parametric generation of high-frequency harmonics in the domainless mode in superlattices with various degrees of dissipation is ...
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High-frequency even harmonics generation in a plasma with electron heat flux
Physics Letters A, 2004It is shown that in a weakly nonuniform plasma with electron heat flux the generation of odd and even harmonics of high frequency radiation is possible. The even harmonics properties qualitatively differ as compared to those of odd harmonics and depend in an essential way on the heat flux value and orientation with respect to the fundamental wave ...
G. FERRANTE +2 more
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High-frequency harmonics and source level of humpback whale songs
The Journal of the Acoustical Society of America, 2001The songs of 8 male humpback whales were recorded at ranges varying from 20 to 40 m with a calibrated system that had a flat frequency response to 22 kHz. The songs consisted of bursts of sounds called units. Units were organized into phrases and phrases into themes.
Whitlow Au +2 more
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A Hybrid Filter Topology for a Reduction of High Frequency Harmonics
2012In this paper a hybrid filter topology for the reduction of the total harmonic distortion in AC sources is introduced. The hybrid filter contains active and passive components. The structure of the digital filter influencing the signals gain and phase will be explained.
J. Bergmann +3 more
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Suppression of harmonics in a high frequency standing-wave thermoacoustic engine
The Journal of the Acoustical Society of America, 2008A thermoacoustic engine converts heat into acoustic power and could be used to driven a cooler for refrigeration purposes or to drive a piston for electric power generation. Due to non-linear effects inside the system, higher order harmonics could be generated which may deteriorate the thermal performance of the whole system.
Wei Dai, Bo Yu, Guoyao Yu, Ercang Luo
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2000 5th International Conference on Actual Problems of Electronic Instrument Engineering Proceedings. APEIE-2000. Devoted to the 50th Anniversary of Novosibirsk State Technical University. Vol.1 (Cat. No.00EX383), 2002
An investigation of the harmonics generation problem is a complicated task due to the wish to have the exact description of the problem that leads to a large volume of necessary calculations and experiments. The coupling simulation of network and electrotechnological installations, for example, 400 kW/0.44 MHz, which can correspond, for example, to HF ...
Y. Blinov, B. Kachanov, V. Ishin
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An investigation of the harmonics generation problem is a complicated task due to the wish to have the exact description of the problem that leads to a large volume of necessary calculations and experiments. The coupling simulation of network and electrotechnological installations, for example, 400 kW/0.44 MHz, which can correspond, for example, to HF ...
Y. Blinov, B. Kachanov, V. Ishin
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CARDIOVASCULAR HARMONICS DURING HIGH FREQUENCY VENTILATION
Critical Care Medicine, 1982Frank R. Gioia +3 more
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Comparison of harmonic scalpel and high-frequency electrocautery in radial artery harvesting.
The Journal of cardiovascular surgery, 2008We evaluated the effects of the radial artery on the functional outcomes and endothelium when the harvest was made either by harmonic scalpel or by high-frequency electrocautery.Between 2002 and 2007, 982 patients with coronary artery diseases were operated for coronary artery revascularization.
Karapolat, S. +6 more
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