Choice of low-pass filter influences practical interpretation of ball kicking motions: the effect of a time-frequency filter method

A novel capacitance multiplier is proposed to implement an ultra-low-frequency filter for physiological signal processing in biomedical applications. With the proposed multiplier, a simple first-order low-pass filter achieves a [Formula: see text]3-dB frequency of 33.4[Formula: see text]μHz with a 1-pF capacitance and a 20[Formula: see text]k[Formula: see text] resistance. This corresponds to a multiplication factor of as large as [Formula: see text]. By changing the controlling terminal, the [Formula: see text]3-dB frequency can be tuned in a wide range of 33.4[Formula: see text]μHz–6.3[Formula: see text]kHz.

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Real-Time Filter Method Based on the Structural Frequency of FAST Cabin-Cable System

Advances in Mechanical Engineering ◽

10.1155/2014/129302 ◽

2014 ◽

Vol 6 ◽

pp. 129302

Author(s):

Wenhua Xu ◽

Hong Bao ◽

Jianwei Mi ◽

Guigeng Yang

Keyword(s):

Real Time ◽

Fundamental Frequency ◽

Variable Structure ◽

Measured Data ◽

Filter Method ◽

Great Flexibility ◽

Cable System ◽

Pass Filter ◽

Low Pass Filter ◽

Low Pass

Due to great flexibility, low damping, and variable structure in the cabin-cable system of five hundred meter Aperture Spherical Radio Telescope (FAST), a real-time digital low-pass filter based on the analysis of frequency is presented in this paper. Firstly, by the Lomb-Scargle theorem, it can obtain the fundamental frequency of cabin-cable system. Then, using the obtained frequency, a digital low-pass filter is designed to filter the measured data. After being filtered, the measured data are used for coarse control. Finally, the results of the experiments on the FAST 5 m model show that calculating the fundamental frequency is accurate and the filter is effective.

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The design of double ridge waveguide filter using conventional stepped impedance low-pass filter method

Microwave and Optical Technology Letters ◽

10.1002/mop.28022 ◽

2013 ◽

Vol 56 (1) ◽

pp. 120-124 ◽

Cited By ~ 3

Author(s):

Mohsen Yazdani ◽

Luke Murphy ◽

Alireza Mallahzadeh ◽

Ercument Arvas ◽

Joseph Mautz

Keyword(s):

Ridge Waveguide ◽

Filter Method ◽

Pass Filter ◽

Low Pass Filter ◽

Low Pass ◽

Waveguide Filter ◽

Double Ridge

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A Low-pass Filter Method to Suppress the Voltage Variations Caused by Introducing Droop Control in DC Microgrids

2018 IEEE Energy Conversion Congress and Exposition (ECCE) ◽

10.1109/ecce.2018.8557455 ◽

2018 ◽

Cited By ~ 1

Author(s):

Fulong Li ◽

Zhengyu Lin ◽

Wenping Cao ◽

Alian Chen ◽

Jiande Wu

Keyword(s):

Filter Method ◽

Droop Control ◽

Pass Filter ◽

Low Pass Filter ◽

Dc Microgrids ◽

Low Pass

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The Research to Image Enhancing Method of Infrared Images

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.562-564.1642 ◽

2012 ◽

Vol 562-564 ◽

pp. 1642-1645

Author(s):

Kui Xia Han ◽

Yan Ling Li ◽

Mei Yu

Keyword(s):

Image Enhancement ◽

Heat Waves ◽

Thermal Image ◽

Filter Method ◽

Infrared Images ◽

Pass Filter ◽

Low Pass Filter ◽

Frequency Selection ◽

Low Pass ◽

Image Enhancing

The contrast is low, and the noise is strong in infrared images, which go against defects judgment and recognition. In order to resolve them, limitations of common methods were analyzed, then, according to characters of infrared images and processing target, grayscale value adjustment method and low pass filter method was introduced. Designed image enhancement steps, and it was applied to process thermal image. In process of index low-pass filtering, the cut-off frequency selection was studied. And, it was found, when it was 40, the effect was ideal. Compared the original image with image after treatment, the validity of this method was verified. There an effective way was designed for heat waves image enhancement.

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