Results 261 to 270 of about 48,016 (315)

Harmonic emission from high frequency gyrotrons

1983 Eighth International Conference on Infrared and Millimeter Waves, 1983
Second harmonic emission of power levels of ≳ 25 kW and frequencies up to 302 GHz have been achieved in a short pulse gyrotron designed for operation at the fundamental in the 110–170 GHz band. Frequency, starting current and power level measurements for several harmonic modes have been made.
J. L. Byerly, B. G. Danly, K. E. Kreischer, P. Woskoboinikow, W. J. Mulligan, R. J. Temkin   +5 more
openaire   +1 more source

High frequency SAW devices based on third harmonic generation

Ultrasonics, 2006
We demonstrate the third harmonic generation in a ZnO/Si layered structure to obtain high frequency SAW devices. This configuration eliminates the need of high lithography resolution and allows easy integration of such devices and electronics on the same wafer.
L, Le Brizoual, O, Elmazria, F, Sarry, M, El Hakiki, A, Talbi, P, Alnot   +5 more
openaire   +2 more sources

High-Frequency Contrast Harmonic Imaging of Ophthalmic Tumor Perfusion

American Journal of Roentgenology, 2005
Schlottmann K, Fuchs-Koelwel B, Demmler-Hackenberg M, Gabel V-P, Scholmerich J he evaluation of symptomatic or incidentally diagnosed ophthalmic tumors usually is performed using funduscopy and Aand B-mode sonography. Additional techniques are Doppler modes [1], fluorescence or indocyanine green angiography [2], CT [3], and MR tomography [4].
Klaus, Schlottmann, Barbara, Fuchs-Koelwel, Martina, Demmler-Hackenberg, Veit-Peter, Gabel, Jürgen, Schölmerich   +4 more
openaire   +2 more sources

High-frequency section of harmonics of undulatory radiation

Soviet Physics Journal, 1991
In this paper, the spectral'distribution is computed of the radiation of an undulator containing a large number of periods in the case of arbitrary transverse velocity. An analytic expression is found for the function cutting off the radiation spectrum on the boundaries of each harmonic.
V. Yu. Muravyatkin, M. M. Nikitin, V. Ya. �pp   +2 more
openaire   +1 more source

High-frequency harmonic distortion in feedback amplifiers: analysis and applications

IEEE Transactions on Circuits and Systems I: Fundamental Theory and Applications, 2003
An approach for the evaluation of high-frequency harmonic-distortion factors in feedback systems is proposed and the results obtained are applied to feedback amplifiers. Under the assumption that transistors are not driven out of their linear operating regions, small-signal analysis and conventional algebra are exploited to derive understandable and ...
PALUMBO, Gaetano, PENNISI, Salvatore
openaire   +2 more sources

Status of a high-frequency harmonic amplifier's development

IEEE Conference Record - Abstracts. 2002 IEEE International Conference on Plasma Science (Cat. No.02CH37340), 2003
Summary form only given, as follows. The harmonic amplifier (HARA) is a very compact, high efficiency amplifier that has been under development at Microwave Technologies in the past few years. The HARA uses a two-cavity system in conjunction with a spiraling beam to produce high-frequency radiation.
J.E. Velazco, P.H. Ceperley
openaire   +1 more source

Influence of high frequency current harmonics on (Smart) energy meters

2015 50th International Universities Power Engineering Conference (UPEC), 2015
(Smart) meters which use Rogowski coils are verified to be sensitive for the high frequency signals. This will lead to incorrect records of consumer's energy consumption. Power electronic devices are the possible harmonic sources. In this paper, the output currents of photovoltaic (PV) systems are measured in the range 2-150kHz and the high frequency ...
Jiang, L., Ye, G., Xiang, Y., Cuk, V., Cobben, J.F.G.   +4 more
openaire   +2 more sources

High frequency resolution harmonic analysis

2016 International Conference on Development and Application Systems (DAS), 2016
The acquisition time of a real life signal limits the resolution of its spectrum, because it directly affects the orthogonality of its spectrum components. There is no spectral analysis yet to distinguish frequencies that are not orthogonal. A spectral analysis for distinguishing non orthogonal frequencies is proposed here. A system of linear equations
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Harmonics of High Frequency Ventilation at 3hz

Pediatrics, 2018
Introduction: High frequency ventilation has allowed clinicians to oxygenate and ventilate patients when conventional ventilation is not sufficient, particularly in premature babies. High frequency ventilation (HFOV) incorporates lung protective strategies including adequate mean airway pressures to sustain alveolar recruitment, and small tidal volumes
openaire   +1 more source

High frequency harmonic imaging in presence of intravascular stents

IEEE Symposium on Ultrasonics, 2003, 2004
High frequency second harmonic imaging was compared with fundamental imaging when highly reflective stents were present in the near field of a spherically focused PVDF transducer. Hydrophone measurements of the harmonic beam at 40 MHz showed a relative lower signal strength in the near field compared to the fundamental modes at 20 and 40 MHz.
M.E. Frijlink, D.E. Goertz, F.S. Foster, A.F.W. van der Steen   +3 more
openaire   +1 more source