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Sensibility to Changes of Vibrational Modes of Excited Electron： Sum Frequency Signals Versus Difference Frequency Signals

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Communications in Theoretical Physics 2011年第3期55卷 506-512页

作者： GU An-Na liang xian-Ting Department of Physics and Institute of Modern Physics Ningbo University Ningbo 315211 China

In this paper, we investigate a two electronic level system with vibrational modes coupled to a Brownian oscillator bath. The difference frequency generation （DFG） signals and sum frequency generation （SFG） signals are calculated. It is shown that, for the same model, the SFG signals are more sensitive than the DFG signals to the changes of the vibrational modes of the electronic two-level system. Because the SFG conversion efficiency can be improved by using the time-delay method, the findings in this paper predict that the SFG spectrum may probe the changes of the microstructure more effectively.

关键词： difference frequency signals sum frequency signals response functions susceptibility

On Fixed Point and Almost Fixed Point Problems of Lower Semicontinuous Type Multivalued Mappings

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Acta Mathematica Sinica,English Series 2005年第5期21卷 1027-1034页

作者： liang Yu LUAN xian WU Institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 P. R. China Department of Mathematics Yunnan Normal University Kunming 650092 P. R. China

In the present paper, some new almost fixed point theorems and fixed point theorems for lower semicontinuous type multivalued mappings are obtained in metrizable H-spaces.

关键词： Lc.-metric space H-space Lower semicontinuous multivalued mapping Locally-uniformly weak lower semicontinuous multivalued mapping

Boundedness of parammetric Marcinkiewicz integrals on weighted Hardy spaces

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Applied Mathematics(A Journal of Chinese Universities) 2015年第3期30卷 253-262页

作者： SHI xian-liang SUN Jie College of Mathematics and Computer Science Key Laboratory of High Performance Computing and Stochastic Information Processing (HPCSIP) (Ministry of Education of China) Hunan Normal University

In this paper, several new results on the boundedness of parammetric Marcinkiewicz integrals on the weighted Hardy spaces and the weak weighted Hardy spaces are established.

关键词： parammetric Marcinkiewicz integral weight function weighted Hardy space weak weighted Hardy space

Preparation of hydroxyapatite layer on Ti-based bulk metallic glasses by acid and alkali pre-treatment

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Rare Metals 2015年第1期34卷 22-27页

作者： Hao hu Zhen-Duo Cui Sheng-Li Zhu Zhao-Yang Li Yan-Qin liang xian-Jin Yang School of Materials Science and Engineering Tianjin University Tianjin Key Laboratory of Composite and Functional Materials

In this paper, a thin calcium phosphate layer was prepared on the surface of Ti4oZr10Cu36Pd14 bulk metallic glasses （BMGs）. All samples were dipped in HNO3 aqueous solution and boiled in 1.2 mol-L-I NaOH aqueous solution. After the two preliminary treatment steps, they were soaked in simulated body fluid （SBF） to form an apatite layer on the surface. After immersion for 12 days, a coating composed mainly of Ca-P particles was rapidly deposited on the surface of Ti40Zr10Cu36Pd14 bulk metallic glasses. The surfaces of chemically treated sam- ples and the samples after immersion in SBF were char- acterized by X-ray diffraction （XRD）, X-ray photoemission spectroscopy （XPS）, field emission scanning electron microscopy （FESEM）, and energy dispersive spectroscopy （EDS）. Analysis results indicate that this apatite coating consists of Ca-P particles with different diameters. In addition, the Ca/P ratio of the apatite coatings immersed for 14 days is 1.62, which is close to that of hydroxyapatite （HA）.

关键词： Metallic glass Titanium alloy Hydroxyapatite Thin film

The Lindblad and Redfield forms derived from the Born–Markov master equation without secular approximation and their applications

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Communications in Theoretical Physics 2021年第9期73卷 68-78页

作者： Chang-Yao Liao xian-Ting liang Department of Physics Ningbo UniversityNingbo 315211China

In this paper,we derive the Lindblad and Redfield forms of the master equation based on the Born–Markov master equation with and without the secular approximation for open multi-level quantum *** coefficients of the equations are re-evaluated according to the scheme in[(2019),***.A 99,022118].They are complex numbers rather than the real numbers obtained from traditional simplified *** dynamics of two models(one is an open threelevel quantum system model,and the other is the model of phycoerythrin 545(PE545)in a photosynthesis system)are *** is shown that the secular approximation and the simplified real coefficients may cause a small distortion of the dynamics in some environments,but a large distortion of the dynamics in *** effects are discussed and characterized by studying the dynamics of nontrivial instances of multi-level systems in the presence of dissipation.

关键词： Master equation secular approximation Redfield form Lindblad form

Intelligent reflecting surfaces-assisted millimeter wave communication:Channel estimation based on deep learning

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The Journal of China Universities of Posts and Telecommunications 2024年第1期31卷 49-56页

作者： Kang Xiaofei Wang Tian liang xian College of Communication and Information Engineering Xi'an University of Science and TechnologyXi'an 710600China

In response to the challenge posed by the complexity of the system and the difficulty in obtaining accurate channel state information(CSI)for millimeter wave communication assisted by intelligent reflecting surfaces(IRS),we propose a deep learning-based channel estimation *** proposed scheme employs a hybrid active/passive IRS architecture,wherein the least square(LS)algorithm is initially utilized to acquire the channel estimate from the active ***,this estimation is interpolated to obtain a preliminary channel estimation and ultimately refined into an accurate estimate of the channel using the channel super-resolution convolutional neural network(Chan-SRCNN)deep learning *** simulation results demonstrate that the proposed scheme surpasses LS,orthogonal matching pursuit(OMP),synchronous OMP(SOMP),and deep neural network(DNN)channel estimation algorithms in terms of normalized mean squared error(NMSE)performance,thereby validating the feasibility of the proposed approach.

关键词： intelligent reflecting surface millimeter wave channel estimation deep learning

Hedgehog signaling pathway regulated the target genes for adipogenesis in silkworm Bombyx moil

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Insect Science 2015年第5期22卷 587-596页

作者： Shuang liang Rui-Ting Chen Deng-Pan Zhang hu-hu Xin Yan Lu Mei-xian Wang Yun-Gen Miao Key Laboratory of Animal Virology of Ministry of Agriculture College of Animal Sciences Zhejiang University Hangzhou 310058 China

Hedgehog （Hh） signals regulate invertebrate and vertebrate development, yet the role of the pathway in adipose development remains poorly understood. In this report, we found that Hh pathway components are expressed in the fat body of silkworm larvae. Functional analysis of these components in a BmN cell line model revealed that activa- tion of the Hh gene stimulated transcription of Hh pathway components, but inhibited the expression of the adipose marker gene AP2. Conversely, specific RNA interference- mediated knockdown of Hh resulted in increased AP2 expression. This further showed the regulation of Hh signal on the adipose marker gene. In silkworm larval models, enhanced adipocyte differentiation and an increase in adipocyte cell size were observed in silkworms that had been treated with a specific Hh signaling pathway antagonist, cyclopamine. The fat-body-specific Hh blockade tests were consistent with Hh signaling inhibiting silkworm adipogenesis. Our results indicate that the role of Hh signaling in inhibiting fat formation is conserved in vertebrates and invertebrates.

关键词： adipocyte differentiation adipogenesis Bombyx mori Hedgehog (Hh) signaling pathway silkworm

Direct Numerical Simulation on Mach Number and Wall Temperature Effects in the Turbulent Flows of Flat-Plate Boundary Layer

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Communications in Computational Physics 2015年第1期17卷 189-212页

作者： xian liang Xinliang Li School of Mathematics and Information Science Beifang University for NationalitiesYinchuan 750021China LHD Institute of MechanicsChinese Academy of SciencesNo.15 Beisihuanxi RoadBeijing 100190China

In this paper,direct numerical simulation(DNS)is presented for spatially evolving turbulent boundary layer over an isothermal flat-plate at Ma∞=2.25,5,6,*** Ma∞=8,two cases with the ratio of wall-to-reference temperature T_(w)/T_(∞)=1.9 and 10.03 are considered *** wall temperature approaches recovery temperatures for other *** characteristics of compressible turbulent boundary layer(CTBL)affected by freestream Mach number and wall temperature are *** focuses on assessing compressibility effects and the validity of Morkovin’s hypothesis through computing and analyzing the mean velocity profile,turbulent intensity,the strong Reynolds analogy(SRA)and possibility density function of dilatation *** results show that,when the wall temperature approaches recovery temperature,the effects of Mach number on compressibility is *** a result,the compressibility effect is very weak and the Morkovin’s hypothesis is still valid for Mach number even up to ***,when Mach number equal to 8,the wall temperature effect on the compressibility is *** this case,when T_(w)/T_(∞)=1.9,the Morkovin’s hypothesis is not fully *** validity of classical SRA depends on wall temperature directly.A new modified SRA is proposed to eliminate such negative factor in near wall *** the effects of Mach number and wall temperature on streaks are also studied.

关键词： Hypersonic directly numerical simulation compressibility effects turbulent boundary layer strong Reynolds analogy

Dynamic p-y curves for vertical and batter pile groups in liquefied sand

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Earthquake Engineering and Engineering Vibration 2022年第3期21卷 605-616页

作者： Zhang Jian Li Yurun Rong xian liang Yan School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China Campus Construction and Management Hebei University of TechnologyTianjin 300401China

In this study,centrifuge model tests of vertical and batter pile groups in liquefied sand were conducted on a centrifuge shaking *** dynamic p-y curves for these pile groups before and during sand liquefaction were obtained from calculations based on test *** results confirm that liquefaction contributes to a reduction in the energy consumption of pile foundations,with the degradation effect being more pronounced for batter pile *** shallow depths,the difference in the backbone gradients of the p-y curves after liquefaction for vertical and batter pile groups indicates that the lateral stiffness of a batter pile group is greater than that of a vertical pile *** shaking intensity increases,the lateral stiffness of a vertical pile group increases with depth during the late stage of sand ***,the lateral stiffness of a batter pile group during liquefaction does not vary with *** results of this study provide a reference for the seismic design of vertical and batter pile groups in liquefied soil.

关键词： soil liquefaction pile-soil interaction p-y curve centrifuge shaking table