Results 211 to 220 of about 638,913 (261)
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Toward quantification of athetotic movements by frequency spectrum analysis
Journal of Biomechanics, 1985The frequency spectrum of the elbow movements of one normal subject and six handicapped subjects were obtained in order to investigate the possibility of using this technique in quantifying athetosis. The frequency spectrum technique appears to be useful but data from more subjects must be obtained and specific details regarding scaling need to be ...
S, Niku, J M, Henderson
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The Significance of Negative Frequencies in Spectrum Analysis
IEEE Transactions on Electromagnetic Compatibility, 1967In EMC measurements spectra generated by pulsed signals are often measured. To calculate the spectra theoretically, Fourier methods are usually used. The Fourier transform yields a spectrum which contains positive and negative frequencies. The exponential form of the Fourier series also yields a spectrum which contains positive and negative frequencies.
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Analysis on crossing frequency in transmission microwave frequency spectrum of the cutoff probe
Physics of Plasmas, 2023Recently, we developed a crossing frequency method using the cutoff probe, which is believed as applicable for measuring electron density regardless of chamber pressures. Although computational and experimental studies demonstrated its operation, the analytic formula for the crossing frequency (fcross) has yet to be investigated.
Si-jun Kim +6 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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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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Analysis of the local frequency spectrum for the chirp signal
2014 International Conference on Informatics, Electronics & Vision (ICIEV), 2014In this article, the statistical moments of the local spectrum obtained from Gabor transform technique for the chirp signal are presented both analytically and numerically. The chirp signal estimation considering only ridge frequency component and electrically band limited frequency components is also discussed.
Md. Mahbub Hasan +3 more
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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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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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Analysis of FDTD cloaking in the visible frequency spectrum
2015 International Conference on Numerical Simulation of Optoelectronic Devices (NUSOD), 2015This work proposes to study the behavior of different wavelengths of light in the visible spectrum when they are incident on a two-dimensional cylindrical structure that appears to be invisible or undetectable due to what is known as a ‘cloak’ formed around the actual object. This is achieved by modifying an existing Finite Difference Time-Domain model
Nadia Anam, Ebad Zahir
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Frequency Sequence Modulation: Analysis of additional Spectrum Space
2019 IEEE AFRICON, 2019This paper proposes a novel method of achieving additional frequency spectrum space at low peak-to-average-power ratio (PAPR), An analogy of genetic coding is applied in order to determine how fewer frequency channels are used to convey more bits to a receiver. Furthermore.
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