National primary standard for the unit of the amplitude modulation coefficient of high-frequency oscillations

2012 ◽  
Vol 55 (1) ◽  
pp. 13-18 ◽  
Author(s):  
A. V. Mylnikov ◽  
V. A. Tishchenko
Keyword(s):  
Amplitude Modulation ◽  
High Frequency ◽  
Primary Standard ◽  
National Primary Standard ◽  
High Frequency Oscillations ◽  
Amplitude Modulation Coefficient ◽  
Modulation Coefficient

New Special Standards of the Frequency Deviation Unit and the Amplitude Modulation Coefficient Unit

2005 ◽  
Vol 48 (3) ◽  
pp. 260-262
Author(s):  
V. L. Ballo ◽  
V. B. Dobrovol’skii ◽  
A. V. Zen’kovich ◽  
V. A. Rekshinskii
Keyword(s):  
Amplitude Modulation ◽  
Frequency Deviation ◽  
Amplitude Modulation Coefficient ◽  
Modulation Coefficient

Amplitude modulation between multi-scale turbulent motions in high-Reynolds-number atmospheric surface layers

2018 ◽  
Vol 861 ◽  
pp. 585-607 ◽  
Author(s):  
Hongyou Liu ◽  
Guohua Wang ◽  
Xiaojing Zheng
Keyword(s):  
Reynolds Number ◽  
Surface Layer ◽  
Amplitude Modulation ◽  
High Reynolds Number ◽  
Quality Data ◽  
Modulation Effect ◽  
Multi Scale ◽  
Amplitude Modulation Coefficient ◽  
High Reynolds ◽  
Modulation Coefficient

Long-term measurements were performed at the Qingtu Lake Observation Array site to obtain high-Reynolds-number atmospheric surface layer flow data ($Re_{\unicode[STIX]{x1D70F}}\sim O(10^{6})$). Based on the selected high-quality data in the near-neutral surface layer, the amplitude modulation between multi-scale turbulent motions is investigated under various Reynolds number conditions. The results show that the amplitude modulation effect may exist in specific motions rather than at all length scales of motion. The most energetic motions with scales larger than the wavelength of the lower wavenumber peak in the energy spectra play a vital role in the amplitude modulation effect; the small scales shorter than the wavelength of the higher wavenumber peak are strongly modulated, whereas the motions with scales ranging between these two peaks neither contribute significantly to the amplitude modulation effect nor are strongly modulated. Based on these results, a method of decomposing the fluctuating velocity is proposed to accurately estimate the degree of amplitude modulation. The corresponding amplitude modulation coefficient is much larger than that estimated by establishing a nominal cutoff wavelength; moreover, it increases log-linearly with the Reynolds number. An empirical model is proposed to parametrize the variation of the amplitude modulation coefficient with the Reynolds number and the wall-normal distance. This study contributes to a better understanding of the interaction between multi-scale turbulent motions and the results may be used to validate and improve existing numerical models of high-Reynolds-number wall turbulence.

Nonlinear Finite Element Analysis on Statically Indeterminate Prestressed Concrete Beam

2012 ◽  
Vol 482-484 ◽  
pp. 647-650
Author(s):  
Shu Tian Fang ◽  
Ying Zhang ◽  
Wen Zhao Zhong
Keyword(s):  
Finite Element ◽  
Bearing Capacity ◽  
Amplitude Modulation ◽  
Prestressed Concrete ◽  
Concrete Beam ◽  
Bending Moment ◽  
Ultimate Bearing Capacity ◽  
Amplitude Modulation Coefficient ◽  
Modulation Coefficient ◽  
Limiting Value

Embarked from the ductility theory, the bending moment amplitude modulation limiting value ductility expression which satisfies the bearing capacity requirements have been deduced，on the value of the bending moment amplitude modulation coefficient, the influence of the using stage crack width limiting value has been considered, and the suggesting formula of the bending moment amplitude modulation coefficient has been proposed. With the aid of APDL language in the ANSYS, the entire process force analysis to statically indeterminate prestressed concrete beam has been carried on, the finite element computed result and the experiment result has been confirmed, through the example drew correlation curve, confirmed with the experiment, the beam's ultimate bearing capacity has been discussed, and the plastic hinge's formation and the influence of moment redistribution to the ultimate bearing capacity has been analyzed.

HIGH FREQUENCY OSCILLATIONS AND ELECTRON BEAM RELAXATION IN HOMOGENEOUS GAS-DISCHARGE PLASMA

1979 ◽  
Vol 40 (C7) ◽  
pp. C7-619-C7-620
Author(s):  
L. L. Pasechnik ◽  
L. I. Romanyuk ◽  
N. Ye. Svavil'ny
Keyword(s):  
Electron Beam ◽  
High Frequency ◽  
Discharge Plasma ◽  
Gas Discharge ◽  
Gas Discharge Plasma ◽  
High Frequency Oscillations

National primary standard machine of Shore D hardness scale for metals and Leeb hardness scales

2020 ◽  
pp. 6-10
Author(s):  
A.E. Aslanyan ◽  
E.G. Aslanyan ◽  
S.M. Gavrilkin ◽  
A.S. Doynikov ◽  
A.N. Shchipunov
Keyword(s):  
Measurement Uncertainty ◽  
Primary Standard ◽  
Metrological Characteristics ◽  
National Primary Standard ◽  
Hardness Scale ◽  
Leeb Hardness

The article presents the results of studies to improve the National primary standard machine for hardness of metals on the shore D scale GET 161-2001, which were performed in FSUE “VNIIFTRI” from 2016 to 2018 in accordance with the technical task of Rosstandart.The improvement was carried out in order to ensure the uniformity of hardness measurements on the Leeb scales. The created new parts of the primary standard machine, which are settings for reproducing hardness numbers on the Leeb scales, are considered. Metrological characteristics of the upgraded and adopted National primary standard machine (GET 161-2019) were investigated, the budget of measurement uncertainty was calculated for reproducing hardness numbers on the Leeb scales.

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