The Synthesis of an Adaptive Filter for Automatic Detection and Time Localization of Premotor EEG Patterns of the Human Brain

An adaptive low-pass filter has been synthesized for automatic patterns detection of arbitrary mental movements in records of multidimensional electroencephalograms (EEG). The filter is based on the multivariate singular spectrum analysis. The effective bandwidth of the filter corresponds to the spectrum of the sought patterns of mental activity on the observed EEG time interval. The use of the synthesized filter provided a reliable automatic search for patterns and the correct determination of their time boundaries. The correctness of the results has been confirmed in experiments with 24 volunteers.

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Transfer function analysis of vagal control of heart rate during synchronized vagal stimulation

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1995.269.6.h1931 ◽

1995 ◽

Vol 269 (6) ◽

pp. H1931-H1940 ◽

Cited By ~ 6

Author(s):

A. Mokrane ◽

A. R. LeBlanc ◽

R. Nadeau

Keyword(s):

Heart Rate ◽

Transfer Functions ◽

Vagal Stimulation ◽

Sinus Node ◽

Time Interval ◽

Pass Filter ◽

Dynamic Component ◽

Low Pass Filter ◽

Transfer Function Analysis ◽

Low Pass

Synchronized electrical stimulation was used to study the heart rate (HR) response to fluctuations in parasympathetic input to the sinus node in anesthetized dogs. This was obtained by varying the time interval (interpulse interval) between stimulatory vagal pulses. Spectral methods were used to estimate transfer functions between the excitatory signal and the resulting HR response for different intensities of vagal stimulation. The intensity of vagal stimulation was proportional to the number of pulses delivered in each cardiac cycle. From the estimated transfer functions, and based on a mathematical model of the time course of ACh concentration at the sinus node, filter models were derived by using a system identification approach. HR response was characterized by a combination of two different filter behaviors: a low-pass filter behavior of mean cut-off frequency of 0.065 Hz and an all-pass filter behavior. The magnitude of the low-pass filter gain decreased with increasing intensity of vagal stimulation. The magnitude of the all-pass filter gain increased and then decreased with increasing intensity of vagal stimulation. The all-pass filter characteristics of HR response during synchronized stimulation of the vagus nerves are specific to this mode of stimulation, because they were not observed in nonsynchronized modes of vagal stimulation. We can conclude that, during synchronized vagal stimulation, the HR response exhibits both a slow dynamic component and a fast component related to beat-to-beat variations.

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Determination of appropriate substrate for microstrip low-pass filter employing square designed tschebycheff distribution

2015 18th International Conference on Computer and Information Technology (ICCIT) ◽

10.1109/iccitechn.2015.7488133 ◽

2015 ◽

Cited By ~ 6

Author(s):

Shakhawat Parvez ◽

Nazmus Sakib ◽

Md. Nurunnabi Mollah

Keyword(s):

Pass Filter ◽

Low Pass Filter ◽

Low Pass

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Preset time count rate meter using adaptive digital signal processing

Nuclear Technology and Radiation Protection ◽

10.2298/ntrp0501064z ◽

2005 ◽

Vol 20 (1) ◽

pp. 64-73 ◽

Cited By ~ 3

Author(s):

Aleksandar Zigic

Keyword(s):

Signal Processing ◽

Count Rate ◽

Time Interval ◽

Adaptation Algorithm ◽

Pass Filter ◽

Low Pass Filter ◽

Low Pass ◽

Preset Time ◽

The Mean ◽

Low Pass Filters

Two presented methods were developed to improve classical preset time count rate meters by using adapt able signal processing tools. An optimized detection algorithm that senses the change of mean count rate was implemented in both methods. Three low-pass filters of various structures with adaptable parameters to implement the control of the mean count rate error by suppressing the fluctuations in a controllable way, were considered and one of them implemented in both methods. An adaptation algorithm for preset time interval calculation executed after the low-pass filter was devised and implemented in the first method. This adaptation algorithm makes it possible to obtain shorter preset time intervals for higher stationary mean count rate. The adaptation algorithm for preset time interval calculation executed before the low-pass filter was devised and implemented in the second method. That adaptation algorithm enables sensing of a rapid change of the mean count rate before fluctuations suppression is carried out. Some parameters were fixed to their optimum values after appropriate optimization procedure. Low-pass filters have variable number of stationary coefficients depending on the specified error and the mean count rate. They implement control of the mean count rate error by suppressing fluctuations in a controllable way. The simulated and realized methods, using the developed algorithms, guarantee that the response time shall not exceed 2 s for the mean count rate higher than 2 s-1 and that controllable mean count rate error shall be within the range of ?4% to ?10%.

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FADE SLOPE ESTIMATION USING TIME DOMAIN METHOD

International Journal of Electronics Signals and Systems ◽

10.47893/ijess.2013.1127 ◽

2013 ◽

pp. 1-5

Author(s):

ASURI PRAVEENA KUMARI ◽

T. VENKATA RAMANA ◽

AFROZ SHAIK

Keyword(s):

Standard Deviation ◽

Elevation Angle ◽

Rain Attenuation ◽

Distribution Model ◽

Time Interval ◽

Pass Filter ◽

Low Pass Filter ◽

Filter Bandwidth ◽

University Of Technology ◽

Low Pass

An analysis is made of the measured distributions of the fade slope of rain attenuation, conditional for attenuation values, measured at Eindhoven University of Technology from the satellite Olympus. It is found that the distribution is similar for positive and negative fade slopes and independent of frequency in the range from 12 to 30 GHz. A distribution model for the conditional distribution is found. The only parameter of the distribution is the standard deviation, which is found to be proportional to attenuation level and dependent on rain type, on the low-pass filter bandwidth and on the time interval used in the slope calculation. The observed relation between the standard deviation and attenuation is compared with results from other measurement sites. From this comparison it is found that the fade slope standard deviation is likely to depend on elevation angle and on climate, through its dependence on rain type.

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