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SEG Technical Program Expanded Abstracts 1992, 1992
In signal processing we often perform time shifts. Considering the duality of time domain and frequency domain representations, we may also want to shift the spectrum of a signal. The frequency shift transform is such a process. It is equivalent to complex modulation or demodulation of a signal (Oppenheim, 1987).
Youli Quan, J. M. Harris
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In signal processing we often perform time shifts. Considering the duality of time domain and frequency domain representations, we may also want to shift the spectrum of a signal. The frequency shift transform is such a process. It is equivalent to complex modulation or demodulation of a signal (Oppenheim, 1987).
Youli Quan, J. M. Harris
openaire +1 more source
Frequency Tripling Transformers
Transactions of the American Institute of Electrical Engineers, 1936The possibility of making use of transformer harmonic phenomena for frequency multiplication has long been recognized, but practical applications have been few. Within recent years, however, several frequency tripling transformers have been built for supplying 180 cycle energy to large electric horns and similar devices from 60 cycle sources.
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High frequency transformation ofKalanchoe laciniata
Plant Cell Reports, 1989Leaf explants ofKalanchoe laciniata were cocultivated for different days (2, 4, 6 and 8 days) with disarmedAgrobacterium tumefaciens strains A208SE, GV3111SE and EHA101 carring a binary vector pROA93. The vector contains a cauliflower mosaic virus 35S promotor which drives the coding sequence of neomycin phosphotransferase II (NPT-II) in one direction ...
S R, Jia, M Z, Yang, R, Ott, N H, Chua
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General Parameterized Time-Frequency Transform
IEEE Transactions on Signal Processing, 2014zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Yang, Y. +4 more
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Optical-RF frequency stability transformer
Optics Letters, 2011An optical technique based on stability transfer among modes of a monolithic optical microresonator is proposed for long term frequency stabilization of a radio frequency (RF) oscillator. We show that locking the frequency difference of two microresonator modes with dissimilar sensitivity to an applied forcing function to a master RF oscillator ...
A B, Matsko +4 more
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Wavelet Transform-Based Frequency Tuning ILC
IEEE Transactions on Systems, Man and Cybernetics, Part B (Cybernetics), 2005In this paper, a discrete wavelet transform-based cutoff frequency tuning method is proposed and experimental investigation is reported. In the method, discrete wavelet packet algorithm, as a time-frequency analysis tool, is employed to decompose the tracking error into different frequency regions so that the maximal error component can be identified ...
Bin, Zhang, Danwei, Wang, Yongqiang, Ye
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2008 International Conference on Neural Networks and Signal Processing, 2008
Discrete cosine transform(DCT) is one of the most powerful tools in image processing. In this paper, we show that each basis of the two dimensional discrete cosine transform (2D-DCT) is an ldquoeigenvectorrdquo of the frequency matrix which is used to obtain basis images of a two dimensional frequency transform (2D-FRT).
null Suicheng Gu +2 more
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Discrete cosine transform(DCT) is one of the most powerful tools in image processing. In this paper, we show that each basis of the two dimensional discrete cosine transform (2D-DCT) is an ldquoeigenvectorrdquo of the frequency matrix which is used to obtain basis images of a two dimensional frequency transform (2D-FRT).
null Suicheng Gu +2 more
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Proceedings of the IRE, 1927
In the foregoing paper a method for calculating the amplification curve of an audio frequency transformer is developed in terms of the usual constants of the transformer and of the tube. The distributed capacity of the coils and the mutual capacity between the primary and secondary coils are represented by lumped capacities. The exciting current of the
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In the foregoing paper a method for calculating the amplification curve of an audio frequency transformer is developed in terms of the usual constants of the transformer and of the tube. The distributed capacity of the coils and the mutual capacity between the primary and secondary coils are represented by lumped capacities. The exciting current of the
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Tomography time-frequency transform
IEEE Transactions on Signal Processing, 2002The paper shows that the fractional Fourier transform (FRFT) of a signal is the Radon transform of the time-frequency distribution of the same signal. Therefore, a time-frequency distribution known as the tomography time-frequency transform (TTFT) is defined as the inverse Radon transform of the FRFT of the signal.
null Feng Zhang +2 more
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Low frequency vibrator transformation
82nd EAGE Annual Conference & Exhibition, 2021Summary A seismic vibrator has been transformed into a powerful low frequency source by taking advantage of an underutilized asset: the carrier vehicle’s mass. At very low frequencies, a portion of vehicle mass is compliantly coupled to the reaction mass by hydraulic dampers.
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