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Noise helped manifestation of intrinsic frequency:A case study in the mesoscopic hormone signaling system

Progress in Natural Science:Materials International 2009年第10期19卷 1209-1214页

作者： Lin Ji a,,Yuanyuan Zhang a,Xiufeng Lang b,Wenxiang Hu a,Qianshu Li c a Department of Chemistry,Capital Normal University,Beijing 100048,China b School of Science,Beijing University of Aeronautics and Astronautics,Beijing 100191,China c The Institute for Chemical Physics,Beijing Institute of Technology,Beijing 100081,China [a]Department of Chemistry Capital Normal University Beijing 100048 China [b]School of Science Beijing University of Aeronautics and Astronautics Beijing 100191 China [c]The Institute for Chemical Physics Beijing Institute of Technology Beijing 100081 China

The selective sustainment of nonlinear systems to signals is of great significance to signal transduction in living *** take hormone signaling as an example,and investigate the sustainment of internal and external *** results prove that signals with "intrinsic frequency",no matter if it is noise induced or external injected,can be selectively sustained by exploiting internal and/or external *** the internal and external noise can optimize the noise-induced signals,and the optimization is rather robust to the disturbance of external signals with other *** results are of significance for weak signal detection and transduction in the presence of external signals.

关键词： Noise intrinsic frequency Mesoscopic system

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Inertial gravity wave parameters for the lower stratosphere from radiosonde data over China

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Science China Earth Sciences 2017年第2期60卷 328-340页

作者： BAI ZhiXuan BIAN JianChun CHEN HongBin CHEN Lei Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth Sciences University of Chinese Academy of SciencesBeijing 100049China Northwest Institute of Nuclear Technology Urumqi 841700China

Characterization of gravity wave （GW） parameters for the stratosphere is critical for global atmospheric circulation models. These parameters are mainly determined from measurements. Here, we investigate variation in inertial GW activity with season and latitude in the lower stratosphere （18-25 km） over China, using radiosonde data with a high vertical resolution over a 2-year period. Eight radiosonde stations were selected across China, with a latitudinal range of 22°-49°N. Analyses show that the GW energy in the lower stratosphere over China has obvious seasonal variation and a meridional distribution, similar to other regions of the globe. The GW energy is highest in winter, and lowest in summer; it decreases with increasing latitude. Velocity perturbations with longitude and latitude are almost the same, indicating that GW energy is horizontally isotropic. Typically, 85% of the vertical wavelength distribution is concentrated between elevations of 1 and 3 km, with a mean value of 2 kin; it is almost constant with latitude. Over 80% of all the horizontal wavelengths occur in the range 100-800 km, with a mean value of 450 km; they show a weak decrease with increasing latitude, yielding a difference of about 40 km over the 22°-49°N range. The ratio of horizontal wavelength over vertical wavelength is about 200：1, which implies that inertial GWs in the lower stratosphere propagate along nearly horizontal planes. Ratios of their intrinsic frequency to the Coriolis parameter decrease with increasing latitude; most values are between 1 and 2, with a mean value of 1.5. Study of the propagation directions of GW energy shows that upward fractions account for over 60% at all stations. In contrast, the horizontal propagation direction is significantly anisotropic, and is mainly along prevailing wind directions; this anisotropy weakens with increasing latitude.

关键词： Inertial gravity wave Lower stratosphere Energy density intrinsic frequency Propagation direction SeasonalVariation Latitudinal variation Velocity perturbations

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Case study on stratospheric and mesospheric concentric gravity waves generated by deep convection

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Earth and Planetary Physics 2021年第1期5卷 79-89页

作者： GuoChun Shi Xiong Hu ZhiGang Yao WenJie Guo MingChen Sun XiaoYan Gong National Space Science Center Chinese Academy of SciencesBeijing 100190China Beijing Institution of Applied Meteorology Beijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Concentric gravity waves(CGWs)in the middle and upper atmosphere show wave-coupling processes between the lower atmosphere and the middle and upper *** this research,we analyzed a case of CGWs detected simultaneously by the AIRS(Atmospheric Infrared Sounder)and the VIIRS/DNB(Day/Night Band of the Visible Infrared Imager Radiometer Suite)in the stratosphere and *** showed that gravity waves(GWs)were generated by the collocated Hurricane Bejisa on the island of *** AIRS data showed arc-like phase fronts of GWs with horizontal wavelengths of 190 and 150 km at 21:08 coordinated universal time(UTC)on 1 January 2014 and at 10:00 UTC on 2 January 2014,whereas the DNB observed arced GWs with horizontal wavelengths of 60 and 150 km in the same geographic regions at 22:24 *** characteristics of CGW parameters in the stratosphere(~40 km)and the mesosphere(~87 km),such as the vertical wavelength,intrinsic frequency,and intrinsic horizontal phase speed,were first derived together with the background winds from ERA5 reanalysis data and Horizontal Wind Model data through the dispersion relationship of GWs and the wind-filtering theory.

关键词： concentric gravity waves wavelength intrinsic frequency phase speed

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Statistics of gravity waves in the lower stratosphere over Beijing based on high vertical resolution radiosonde

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Science China Earth Sciences 2005年第9期 222-232页

作者： BIAN Jianchun, CHEN Hongbin & LU Daren Institute of Atmospheric Sciences, Chinese Academy of Sciences, Beijing 100029, China

The seasonal variation of inertia gravity-wave activity in the lower stratosphere (17―24 km) over Beijing is studied based on the high vertical resolution radionsonde observa- tions (from December 2001 to February 2003) of Beijing Observatory (116°28′E, 39°48′N). Some of the important gravity-wave parameters, such as intrinsic frequency, and propagation direction, are estimated according to the polarized relation among gravity-wave wind components and temperature. Time series of wave energy show that the largest wave amplitudes occur during the winter and the least during the summer, and the average of the KE:PE ratios is about 2.6. Zonal and meridional wind perturbations have almost the same roots of mean variances, which shows that the wave energy in the lower stratosphere is isotropic horizontally. The motion and tem- perature fields are dominated by waves with vertical wavelengths of 1.5―3 km, which occupy above 80% samples, with a mean value of about 2.3 km. The horizontal wavelengths are mainly distributed between 100―800 km, averaging 445 km. The ratio of the mean horizontal to vertical wavelength is about 200:1, which indicates that the wave propagates nearly horizontally, with a very small vertical angle. The intrinsic frequency is estimated by fitting a polarized ellipse to the wind perturbations after band-filtering waves with a wavelength of 1.5―3 km, and the results show that the intrinsic frequency is dominated by 1f―3.5f, with an averaging value of 2f, corre- sponding to an intrinsic time period of 9 hours. Wave energy is found to propagate mainly upward, and in the horizontal direction, there is clear azimuthal anisotropy, with predominate northwest propagation against the prevailing wind.

关键词： inertia gravity waves lower stratosphere polarized relation intrinsic frequency propagation direction.

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