Results 41 to 50 of about 3,059,110 (191)

Regular Representations of Time-Frequency Groups

, 2013
In this paper, we study the Plancherel measure of a class of non-connected nilpotent groups which is of special interest in Gabor theory. Let $G$ be a time-frequency group.
Baggett, Bownik, Cariolaro, Corwin, Currey, Folland, Folland, Führ, Gabor, Gröchenig, Han, Kaniuth, Kleppner, Lipsman, Pfander, Wolf   +15 more
core   +1 more source

The Stationary Phase Approximation, Time-Frequency Decomposition and Auditory Processing [PDF]

, 2012
The principle of stationary phase (PSP) is re-examined in the context of linear time-frequency (TF) decomposition using Gaussian, gammatone and gammachirp filters at uniform, logarithmic and cochlear spacings in frequency. This necessitates consideration
Mulgrew, Bernard
core   +2 more sources

Redefinition of the SI Base Units: Its Background and Principle [PDF]

한국정밀공학회지, 2018
The International System of Units (acronym: SI) is founded on seven base units (meter, kilogram, second, ampere, kelvin, mole, and candela) corresponding to seven base quantities (length, mass, time, electric current, thermodynamic temperature, amount of
Ho Seong Lee
doaj   +1 more source

Audio Classification from Time-Frequency Texture

, 2008
Time-frequency representations of audio signals often resemble texture images. This paper derives a simple audio classification algorithm based on treating sound spectrograms as texture images.
Slotine, Jean-Jacques, Yu, Guoshen
core   +1 more source

The weak frequency anomaly detection method of atomic clocks based on Kalman filter and extrapolation-accumulation

Measurement + Control, 2021
A new method based on the innovation of Kalman filter and extrapolation-accumulation is proposed to detect weak frequency anomalies in atomic clocks with short detection time and high detection probability. In this method, the detection statistics of the
Ran Yan, Junliang Liu, Jianfeng Wu, Chao Xu, Yonghui Hu   +4 more
doaj   +1 more source

Time-Frequency Transfer with Quantum Fields

, 1996
Clock synchronisation relies on time-frequency transfer procedures which involve quantum fields. We use the conformal symmetry of such fields to define as quantum operators the time and frequency exchanged in transfer procedures and to describe their ...
A. Einstein, A. Einstein, A. Einstein, A. Eistein, C. Itzykson, C. Itzykson, C. Rovelli, E. Cunningham, E. P. Wigner, H. Bateman, H. Salecker, J. D. Norton, M. T. Jaekel, M. T. Jaekel, Marc-Thierry Jaekel, S. A. Fulling, S. M. Barnett, Serge Reynaud, T. D. Newton, T. Fulton, V. L. Ginzburg, W. G. Unruh   +21 more
core   +1 more source

Semi-classical Time-frequency Analysis and Applications

, 2016
This work represents a first systematic attempt to create a common ground for semi-classical and time-frequency analysis. These two different areas combined together provide interesting outcomes in terms of Schr\"odinger type equations.
Cordero, Elena, de Gosson, Maurice, Nicola, Fabio   +2 more
core   +1 more source

Effect of sparsity-aware time–frequency analysis on dynamic hand gesture classification with radar micro-Doppler signatures [PDF]

, 2018
Dynamic hand gesture recognition is of great importance in human-computer interaction. In this study, the authors investigate the effect of sparsity-driven time-frequency analysis on hand gesture classification.
Fioranelli, Francesco, Griffiths, Hugh, Li, Gang, Zhang, Shimeng   +3 more
core   +1 more source

The research of 369.5 nm laser stabilizing method and its influence on ytterbium ion optical clock

AIP Advances
The 369.5 nm laser serves as the cooling laser for ytterbium-ion optical clocks, and its frequency instability directly affects the intensity of ion fluorescence. This paper compares two stabilization methods for a 369.5 nm frequency-tripled fiber laser:
Shaoyang Dai, Chaowei Wang, Shiying Cao, Yani Zuo, Kun Liu, Weiliang Chen, Fasong Zheng, Wenbo Zhao, Fang Fang   +8 more
doaj   +1 more source

Photonic bandgap microcombs at 1064 nm

APL Photonics
Microresonator frequency combs and their design versatility have revolutionized research areas from data communication to exoplanet searches. While microcombs in the 1550 nm band are well documented, there is interest in using microcombs in other bands ...
Grisha Spektor, Jizhao Zang, Atasi Dan, Travis C. Briles, Grant M. Brodnik, Haixin Liu, Jennifer A. Black, David R. Carlson, Scott B. Papp   +8 more
doaj   +1 more source