Results 241 to 250 of about 1,968,691 (295)
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Computer analysis of frequency spectrum of a phonothyreogram
Medical & Biological Engineering & Computing, 1979An analysis of phonothyreograms and phonocardiograms was made with the aid of an ND minicomputer and a CYBER 73 computer system using an electrocardiogram signal as a reference time signal. Programs were written to estimate the power spectral density function of these signals. In patients with Graves' disease and those with nodular goiter the intrinsic
K J, Blinowska +3 more
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Ultrasonic radio-frequency spectrum analysis of normal brain tissue
Ultraschall in der Medizin - European Journal of Ultrasound, 2007Acoustic tissue properties can be estimated using texture and/or spectral parameter analysis. Spectral analysis is based on the rf-signals whose frequency-content is commonly neglected in conventional B-mode imaging. Attenuation and backscatter values of normal brain tissue were analyzed. Unprocessed rf-data of 20 patients were sampled intraoperatively
Martin, Strowitzki +2 more
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Clinical Usefulness Of ECG Frequency Spectrum Analysis
The Second Annual Symposium on Computer Application in Medical Care, 1978. Proceedings., 2005The QRS portion of the electrocardiogram of the complexes of patients were sampled at the rate of 1024 samples per second. The power spectral densities were calculated using the fast Fourier transform on a quarter of a second portion of an FM recorded ECG, centered on the peak of the R wave.
V.K. Murthy +3 more
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Isolating low frequency activity in EEG spectrum analysis
Electroencephalography and Clinical Neurophysiology, 1979A method for isolating and removing very slow activity from EEG records prior to spectrum computation is presented. This is accomplished by an autoregressive filter whose frequency transfer characteristic can be easily controlled. Examples of spectra computed for various filter parameter values are shown.
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Nonlinear frequency spectrum in nonlinear structural analysis
Computers & Structures, 1992Abstract This paper deals with the nonlinear frequency spectrum in nonlinear structural analysis. Iterative perturbation is presented as an effective method for extracting the nonlinear frequency spectrum. The iterative perturbation is based on matrix perturbation. The initial frequencies are found by subspace iteration.
Su-Huan Chen, Tao Xu, Zhong-Sheng Liu
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Modified Pisarenko spectrum for frequency analysis
2018 7th Mediterranean Conference on Embedded Computing (MECO), 2018We present a parametric spectral analysis algorithm that aims to visualize sinusoidal components in a sampled signal. The algorithm represents a signal as the moments of a rational weight function defined on the unit circle. We also propose an averaging procedure for visualizing the weight function.
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75 GHz 5G Frequency Spectrum Analysis
2019The endless improvement in the 5G remote developments is asking for higher exchange speed, which is an endeavoring attempt to fulfill with the present repeat extend underneath 5 GHz. It powers chairmen in addition to researchers to go on behalf of superior repeat shot-wield (mm-wave) run all together achieve increasingly evident information exchange ...
Sireesha Pendem, G. P. Ramesh
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Frequency Compensation Technology Based on Spectrum Analysis
2010 First International Conference on Pervasive Computing, Signal Processing and Applications, 2010This paper presents a frequency compensation technology which uses spectrum analysis. First this method uses cross power spectrum to measure the frequency response of the hardware input channel which is to be compensated H(k). Second, put the signal which output by the hardware input into FFT transform, and get the spectrum of the output signal, Yr(k);
Ji Tiejun, Gai Jianxin
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Simplified Instrumentation for Low Frequency Spectrum Analysis
Review of Scientific Instruments, 1971Three techniques are described for the analog computation of Fourier series parameters of data signals stored on multichannel magnetic tape loops. Logic signals on the tape loop control the operation of circuits used to generate the Fourier sine integral. The techniques consist of using circuits which modify one of three variables: test frequency, test
Jack G. Parks, Richard L. Coulter
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High-resolution frequency-wavenumber spectrum analysis
Proceedings of the IEEE, 1969The output of an array of sansors is considered to be a homogeneous random field. In this case there is a spectral representation for this field, similar to that for stationary random processes, which consists of a superposition of traveling waves. The frequency-wavenumber power spectral density provides the mean-square value for the amplitudes of ...
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