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Large-eddy simulation of circular cylinder flow at subcritical Reynolds number:Turbulent wake and sound radiation

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Acta Mechanica Sinica 2016年第1期32卷 1-11页

作者： Li guo xing Zhang guowei He China Academy of Aerospace Aerodynamics Beijing 100074China State Key Laboratory of Non-linear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China

The flows past a number 3900 are simulated circular cylinder at Reynolds using large-eddy simulation （LES） and the far-field sound is calculated from the LES results. A low dissipation energy-conserving finite volume scheme is used to discretize the incompressible Navier- Stokes equations. The dynamic global coefficient version of the Vreman＇s subgrid scale （SGS） model is used to com- pute the sub-grid stresses. Curie＇s integral of Lighthill＇s acoustic analogy is used to extract the sound radiated from the cylinder. The profiles of mean velocity and turbulent fluctua- tions obtained are consistent with the previous experimental and computational results. The sound radiation at far field exhibits the characteristic of a dipole and directivity. The sound spectra display the -5/3 power law. It is shown that Vreman＇s SGS model in company with dynamic procedure is suitable for LES of turbulence generated noise.

关键词： Flows past circular cylinder Aerodynamicnoise Large-eddy simulation Unstructured grid Acousticanalogy

Complex variable method for an anti-plane elliptical cavity of one-dimensional hexagonal piezoelectric quasicrystals

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Chinese Journal of Aeronautics 2015年第4期28卷 1287-1295页

作者： Yu Jing guo Junhong xing Yongming School of Science Inner Mongolia University of Technology College of General Education Inner Mongolia Normal University

Based on the fundamental equations of piezoelasticity of quasicrystal media, using the symmetry operations of point groups, the linear piezoelasticity behavior of one-dimensional（1D）hexagonal quasicrystals is investigated and the piezoelasticity problem of 1D hexagonal quasicrystals is decomposed into two uncoupled problems, i.e., the classical plane elasticity problem of conventional hexagonal crystals and the phonon–phason-electric coupling elasticity problem of1 D hexagonal *** final governing equations are derived for the phonon–phasonelectric coupling anti-plane elasticity of 1D hexagonal *** complex variable method for an anti-plane elliptical cavity in 1D hexagonal piezoelectric quasicrystals is proposed and the exact solutions of complex potential functions, the stresses and displacements of the phonon and the phason fields, the electric displacements and the electric potential are obtained *** the cavity into a crack, the explicit solutions in closed forms of electro–elastic fields,the field intensity factors and the energy release rate near the crack tip are derived.

关键词： Complex variable methodElliptical cavity Fracture mechanics Piezoelasticity Quasicrystals

DS-CDMA system outer loop power control and improvement for multi-service

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Journal of Systems Engineering and Electronics 2008年第3期19卷 453-460页

作者： Guan Mingxiang guo Qing Li xing School of Electronic and Information Technology Harbin Inst. of Technology Harbin 150001 P.R. China Huawei Technologies Co. Ltd Shenzhen 518057 P. R. China

When a new user accesses the CDMA system, the load will change drastically, and therefore, the advanced outer loop power control （OLPC） technology has to be adopted to enrich the target signal interference ratio （Silt） and improve the system performance. The existing problems about DS-CDMA outer loop power control for multi-service are introduced and the power control theoretical model is analyzed. System simulation is adopted on how to obtain the theoretical performance and parameter optimization of the power control algorithm. The OLPC algorithm is improved and the performance comparisons between the old algorithm and the improved algorithm are given. The results show good performance of the improved OLPC algorithm and prove the validity of the improved method for multi-service.

关键词： DS-CDMA outer loop power control multi-service performance.

Sunspot rotation and magnetic transients associated with flares in NOAAAR 11429

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Research in Astronomy and Astrophysics 2017年第8期17卷 47-56页

作者： Jian-Chuan Zheng Zhi-Liang Yang Jian-peng guo Kai-Ming guo Hui Huang Xuan Song Wei-xing Wan Department of Astronomy Beijing Normal University Beijing 100875 China Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy ofSciences Beijing 100029 China College of Earth Sciences University of Chinese Academy of Sciences Beijing 100049 China

We analyze sunspot rotation and magnetic transients in NOAA AR 11429 during two X-class(X5.4 and X1.3)flares using data from the Helioseismic and Magnetic Imager on board the Solar Dynamics Observatory.A large leading sunspot with positive magnetic polarity rotated *** expected,the rotation was significantly affected by the two *** transients induced by the flares were clearly evident in the sunspots with negative *** were moving across the sunspots with speed of order 3-7 km ***,the trend of magnetic flux evolution in these sunspots exhibited changes associated with the *** results may shed light on understanding the evolution of sunspots.

关键词： sunspots—Sun rotation—Sun magnetic fields

Seminal plasma miR-192a： a biomarker predicting successful resolution of nonobstructive azoospermia following varicocele repair

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Asian Journal of Andrology 2018年第4期20卷 396-399页

作者： Er-Lei Zhi guo-Qing Liang peng Li Hui-xing Chen Ru-Hui Tian peng Xu Zheng Li Department of Andrology Center for Men's Health Department of ART Institute of Urologic Medical Center Shanghai General Hospital Shanghai Key Lab of Reproductive Medicine Shanghai Jiao Tong University 100 Haining Road Shanghai 200080 China Department of Andrology Seventh People's Hospital of Shangha University of TCM Shanghai 200000 China Oriental Jinghua Hospital of Shenyang Department of ART 156 Nanjing Road Shenyang 110005 China

This study was performed to investigate a potential marker for the presence of spermatozoa in the ejaculate following varicocelectomy in Chinese men with nonobstructive azoospermia and varicoceles. The micro-RNA （miR）-192a levels in seminal plasma and testicular tissue were evaluated by quantitative real-time polymerase chain reaction from 60 men with nonobstructive azoospermia and varicoceles （Group A： 27 men with spermatozoa found in the ejaculate after surgery; Group B： 33 men without spermatozoa found in the ejaculate after surgery） and 30 controls. The seminal plasma and testicular tissue miR-192a levels were higher in Group B than in Group A and the controls （P〈 0.001）, and there was no significant difference between Group A and the controls （P〉 0.05）. Apoptosis and proliferation assays with miR mimics and inhibitors showed that miR-192a induced GC-2 cell apoptosis through the activation of Caspase-3 protein. Thus, seminal plasma miR-192a appears to be a potential marker for successfully indicating spermatozoa in the ejaculate following microsurgical varicocelectomy in men with nonobstructive azoospermia and varicoceles. Seminal plasma miR-192a may be a useful clinical marker for prescreening to determine which patients with nonobstructive azoospermia and varicoceles would benefit from varicocelectomy.

关键词： miR-192a nonobstructive azoospermia seminal plasma varicocelectomy

Discontinuous slope failures and pore-water pressure variation

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Journal of Mountain Science 2016年第1期13卷 116-125页

作者： guo Xiao-jun LI Yong CUI peng ZHAO Wan-yu JIANG xing-yuan YAN Yan Key Laboratory of Mountain Hazards and Earth Surface Processes/Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 61o041China Asian Network on Debris Flow Chengdu 610041China University of Chinese Academy of Sciences Beijing 100049China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100049China

Field experiments were conducted under artificial rainfalls to investigate the processes of soil failures on *** is found that the failures were temporally discontinuous and spatially discrete,with a wide range of magnitudes,accompanied by variations of soil moisture and pore-water ***,the experiments indicate that soil failures are more likely to occur on slope with high content of fine particles;the pore-pressure varies in response to soil failures in that the failures evidently affect the pore of the underlying *** of fine particles from upper to lower part of the slope also impacts the pore-water pressure variations in the slope *** is concluded that soil heterogeneity has a significant effect on variation in pore-water pressure,and fine particles transportation influences the building of pore-water pressure,as well as the mass depth,initial porosity,which is key to understanding the spatial characteristics of slope failures.

关键词： porosity heterogeneity spatially concluded likely moisture slide discontinuous rainfall accompanied

Measuring CP violation in rare W decays at the LHC

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Chinese Physics C 2022年第10期46卷 107-115页

作者： peng-Cheng Lu Zong-guo Si Zhe Wang xing-Hua Yang School of Physics Shandong UniversityJinan 250100China School of Physics and Optoelectronic Engineering Shandong University of TechnologyZibo 255000China

Heavy Majorana neutrinos beyond the standard model can simultaneously explain the origin of tiny neutRino masses and matter-antimatter asymmetry in our *** existence of heavy Majorana neutrinos will also lead to lepton number violation and confirm the possibility of rare lepton-number-violating W *** contributions from two different Majorana neutrinos,nonzero CP asymmetry may be generated from the rate difference between W decay and its CP-conjugate *** aim of this study is to investigate the prospects of measuring CP violation in rare w decays via Majorana neutRInos at the *** calculations show that the induced CP asymmetry is independent of the Majorana neutrino mass for 15guous evidence of new physics beyond the standard model.

关键词： lepton number violation W decay Majorana CP violation

Exceptional Cycles in the Bounded Derived Categories of Quivers

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Acta Mathematica Sinica,English Series 2020年第3期36卷 207-223页

作者： peng guo Pu ZHANG School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240P.R.C hina

An exceptional n-cycle in a Hom-finite triangulated category with Serre functor has been recently introduced by Broomhead,Pauksztello and *** n=1,it is a spherical *** explicitly determine all the exceptional cycles in the bounded derived category D^b(kQ)of a finite quiver Q without oriented *** particular,if Q is an Euclidean quiver,then the length type of exceptional cycles in D^b(kQ)is exactly the tubular type of Q;if Q is a Dynkin quiver of type E_m(m=6,7,8),or Q is a wild quiver,then there are no exceptional cycles in D^b(kQ);and if Q is a Dynkin quiver of type An or D_n,then the length of an exceptional cycle in D^b(kQ)is either h or h/2,where h is the Coxeter number of Q.

关键词： Exceptional cycle the Coxeter number the tubular type the length type

The Martingale Hardy Type Inequalities for Dyadic Derivative and Integral

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Acta Mathematica Sinica,English Series 2005年第6期21卷 1465-1474页

作者： JianYingNIE xing guo Nie guo Wei LOU Institute of Near Sensing Technique with Millimeter Wave & Optical Wave Nanjing University of Science ~ Technology Nanjing 210094 P. R. China

Since the Leibniz-Newton formula for derivatives cannot be used in local fields, it is important to investigate the new concept of derivatives in Walsh-analysis, or harmonic analysis on local fields. On the basis of idea of derivatives introduced by Butzer, Schipp and Wade, Weisz has proved that the maximal operators of the one-dimensional dyadic derivative and integral are bounded from the dyadic Hardy space Hp,q to Lp,q, of weak type （L1,L1）, and the corresponding maximal operators of the two-dimensional case are of weak type （Hi, L1）. In this paper, we show that these maximal operators are bounded both on the dyadic Hardy spaces Hp and the hybrid Hardy spaces H^#p 0〈p≤1.

关键词： martingale Hardy space dyadic derivative dyadic integral Walsh-Fejer kernels p-atom,quasi-local operator