scholarly journals Determination of the Velocity of Meteors Based on Sinodial Modulation and Frequency Analysis

2008 ◽  
pp. 205-208
Author(s):  
Felix Bettonvil
Keyword(s):  
Frequency Analysis

scholarly journals Does the manual insertion torque of smartpegs affect the outcome of implant stability quotients (ISQ) during resonance frequency analysis (RFA)?

2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Ingrid Kästel ◽  
Giles de Quincey ◽  
Jörg Neugebauer ◽  
Robert Sader ◽  
Peter Gehrke
Keyword(s):  
Resonance Frequency ◽  
Frequency Analysis ◽  
Insertion Torque ◽  
Resonance Frequency Analysis ◽  
Implant Stability ◽  
Reliable Determination ◽  
Torque Values ◽  
Finger Pressure

Abstract Background There is disagreement about the optimal torque for tightening smartpegs for resonance frequency analysis (RFA). Subjective finger pressure during hand tightening could affect the reliability of the resulting values. The aim of the current study was therefore to assess whether or not the insertion torque of a smartpeg magnetic device influences the implant stability quotient (ISQ) value during RFA. Methods Thirty self-tapping screw implants (XiVE S, Dentsply Sirona Implants, Bensheim, Germany) with a diameter of 3.8 mm and a length of 11 mm were inserted in three cow ribs with a bone quality of D1. The RFA value of each implant was measured (Ostell, FA W&H Dentalwerk, Bürmoos, Austria) in two orthogonal directions (mesial and buccal) after tightening the corresponding smartpeg type 45 with a mechanically defined value of 5 Ncm (Meg Torq device, Megagen, Daegu, South Korea) (test). Additionally, 4 different examiners measured the RFA after hand tightening the smartpegs, and the results were compared (control). Insertion torque values were determined by measuring the unscrew torque of hand seated smartpegs (Tohnichi Manufacturing Co. Ltd, Tokyo, Japan). Results The ISQ values varied from 2 to 11 Ncm by hand tightening and from 2 to 6 Ncm by machine tightening. The comparison of hand and machine tightening of smartpegs displayed only minor differences in the mean ISQ values with low standard deviations (mesial 79.76 ± 2,11, buccal 77.98 ± 2,) and no statistical difference (mesial p = 0,343 and buccal p = 0,890). Conclusions Manual tightening of smartpeg transducers allows for an objective and reliable determination of ISQ values during RFA.

Determination of sound speed in biological tissues based on frequency analysis of pulse response

1992 ◽  
Vol 92 (3) ◽  
pp. 1564-1568 ◽  
Author(s):  
Hiroyuki Hachiya ◽  
Shigeo Ohtsuki ◽  
Motonao Tanaka ◽  
Floyd Dunn
Keyword(s):  
Frequency Analysis ◽  
Sound Speed ◽  
Biological Tissues ◽  
Pulse Response

Determination of the cutoff frequency of an acoustic circumferential wave using a time–frequency analysis

2000 ◽  
Vol 33 (6) ◽  
pp. 373-376 ◽  
Author(s):  
R Latif ◽  
E Aassif ◽  
A Moudden ◽  
D Decultot ◽  
B Faiz ◽  
...  
Keyword(s):  
Frequency Analysis ◽  
Cutoff Frequency ◽  
Time Frequency Analysis ◽  
Time Frequency ◽  
Circumferential Wave

DETERMINATION OF DYNAMIC RESPONSE COMPUTATION OF CONSTANT VOLTAGE PULSE CONVERTER MICROCHIPS

2021 ◽  
Vol 2021 (3-4) ◽  
pp. 68-76
Author(s):  
Vitaliy Zotin
Keyword(s):  
Experimental Determination ◽  
Frequency Domain ◽  
Frequency Analysis ◽  
Operational Amplifier ◽  
Voltage Pulse ◽  
Pass Filter ◽  
Analysis Scheme ◽  
External Frequency ◽  
Step Down

Work objective is the determination of data on the frequency-domain behavior of components in the composition of the microcircuit and within the microcircuit as a whole, intended for using in DC voltage pulse converters. Research methods: simulation modeling. Research results and novelty: for microcircuits with an external frequency weighing network a frequency analysis scheme using an auxiliary operational amplifier and an active low-pass filter of the second order is proposed. Using a simulator in the LT-spice environment, the amplitude and phase frequency response data of the microchips of the step-down and step-up converters have been obtained. The possibility of technical implementation of the proposed scheme for experimental determination of frequency-domain behavior including final control of the parameters of the appropriate microchips has been noted. For microchips having built-in frequency weighing circuit, the possibility of determining frequency-domain characteristics during the formation of a test signal in an external control circuit has been confirmed. It is found that the use of this method for microchips with increased dynamic properties is problematic. Conclusion: the frequency analysis scheme using an auxiliary operational amplifier is suitable for both step-down and step-up DC/DC converters with an external frequency weighing network. This scheme can be recommended for experimental determination of frequency-domain behavior, including final control of the parameters of the appropriate microchips.

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