Results 211 to 220 of about 175,414 (264)
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Ultra-High Frequency Beam Analyzer
Review of Scientific Instruments, 1954This paper describes a method for presenting on a fluorescent screen the time varying velocity and density modulation of an electron beam, modulated at a frequency of 3000 Mc, as it emerges from the cavities of a klystron, the wave guide in a traveling wave tube, or similar structures.
L. R. Bloom, H. M. VonFoerster
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Ultra high frequency financial data
Proceedings of the 10th annual conference companion on Genetic and evolutionary computation, 2008This note is best described as a 'Research Challenge', and concerns building an ultra high frequency (UHF) trading system. The emphasis is on addressing the problems posed by UHF data, with a few thoughts on strategy and implementation. The problem may be amenable to evolutionary computation.
Martin Victor Sewell, Wei Yan
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Ultra-High-Frequency Oscillography
Proceedings of the IRE, 1940Starting from the transit-time effects of the first and second kind, occurring in a cathode-ray tube, two methods are described for the oscillographic examination of ultra-high-frequency oscillations. First, we have the inversion spectrograph which supplies, by means of a white and spectrally dispersed electron beam, sinusoidal and complex inversion ...
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High-Frequency and Ultra-High Frequency Ultrasound: Musculoskeletal Imaging up to 70 MHz
Seminars in Musculoskeletal Radiology, 2020AbstractMusculoskeletal (MSK) ultrasound has well-established advantages, able to investigate very small structures with high resolution and a quick and real-time dynamic evaluation with the possibility of contralateral comparison. Thus ultrasound has kept its own almost exclusive fields of application in daily clinical practice, and it is considered ...
Albano D. +4 more
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Ultrasound Patterns of Vitiligo at High Frequency and Ultra‐High Frequency
Journal of Ultrasound in MedicineObjectivesTo detect ultrasonographic anatomical alterations in all the skin layers in patients with vitiligo.MethodsA prospective observational color Doppler ultrasound study was performed in nonsegmental face and/or neck vitiligo patients without a history of previous treatments. Two sites, a lesional area and a contralateral clinically healthy region,
Ximena Wortsman +4 more
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A Power Amplifier for Ultra-High Frequencies
Proceedings of the IRE, 1936A consideration of the special problems encountered at ultra-high frequencies has led to the design of a push-pull power pentode, useful as an amplifier, frequency multiplier, and modulator at frequencies of 300 megacycles per second and below. Unusual construction features include the mounting of two pentodes in the same envelope with interconnected ...
A. L. Samuel, N. E. Sowers
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Fact or friction: Jumps at ultra high frequency
Journal of Financial Economics, 2011In this paper, we demonstrate that jumps in financial asset prices are not nearly as common as generally thought, and that they account for only a very small proportion of total return variation. We base our investigation on an extensive set of ultra high-frequency equity and foreign exchange rate data recorded at milli-second precision, allowing us to
Christensen, K. +2 more
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Ultra high frequency-Radio Frequency Identification Tags modeling
2009 International Conference on Advances in Computational Tools for Engineering Applications, 2009Radio Frequency Identification systems are proposed for various applications such as warehouse inventories and supply chain management. A typical RFID system includes two parts: the Reader and the Tags. This paper is concerned with Tag simulation. Tags are components that are physically placed upon each item and consist of an antenna and a chip.
S. A. Chakra +3 more
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Thunderstorm Signals at Very-high Frequency and Ultra-high Frequency
Nature, 1955WHILE signals from distant very-high and ultra-high frequency transmitters were being monitored on June 26, 1954, a thunderstorm occurred in the region of the receivers. The transmitters, which operated at 49, 91, 173 and 492 Mc./s., were some two hundred miles from the receiving site. Fig.
D. R. HAY, T. R. HARTZ
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