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Progress in Natural Science:Materials International 2008年第4期18卷 413-419页

作者： Xiaopeng Cui , Shouting gao Laboratory of Cloud-Precipitation Physics and Severe Storms, Institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, china Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The effects of zonal perturbations of sea surface temperature (SST) on tropical equilibrium states are investigated based on a series of two-dimensional cloud-resolving simulations with imposed zero vertical velocity, constant zonal wind, and a zonal model domain of 768 km. Four experiments with zonal SST perturbations of wavenumbers 1 (C1), 2 (C2), 4 (C3), and 8 (C4) are compared to a control experiment with zonally uniform SST (C0). The 40-day integrations show that the temperatures reach quasi-equilibrium states with dis- tinct differences. C1 and C2 produce warmer equilibrium states whereas C3 and C4 generate colder equilibrium states than C0 does. The heat budgets in the five experiments are analyzed. Compared to C0, less IR cooling over smaller clear-sky regions in C1 and more con- densational heating in C2 are responsible for warmer equilibrium states. A reduced condensational heating leads to the cold equilibrium state in C3. The interaction between convective systems in C4 causes a decrease of condensational heating, which accounts for the cold equilibrium state.

关键词： Tropical equilibrium states Sea surface temperature Zonal perturbation Cloud-resolving modeling study

Dissolved inorganic carbon and CO_(2) fluxes across Jiaozhou Bay air-water interface

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Acta Oceanologica Sinica 2004年第2期23卷 279-285页

作者： LIXuegang LINing gaoXuelu SONGJinming InstituteofOceanology ChineseAcademyofSciencesQingdao266071China GraduateSchool ChineseAcademyofSciencesBeijing100039China

On the basis of data collected in the Jiaozhou Bay in June and July 2003, the DIC distribution in seawater is studied, and an average air-sea flux of CO2 is estimated. The results show that the content of DIC inside the bay is markedly higher than outside the bay in June, but the content of DIC outside the bay is markedly higher than inside the bay in July. The trend of DIC distribution inside the bay is similar, viz. the content is the maximum in the northeast, then decreases gradually toward the west, and the content is the minimum in the west. The total trend of vertical distribution is to increase gradually from surface to bottom. This characteristic of DIC distribution is determined by Jiaozhou Bay hydrology and there is a close relation between DIC and particulate N,P. Average CO2flux across the air-sea interface is 0.55 mol/(m2-a) in June and 0.72 mol/(m2-a) in July. Jiaozhou Bay is considered as a net annual source for atmospheric CO2 in June and July, and the total CO2 flux from seawater into atmosphere is about 740t in June and 969 t in July.

关键词： DIC flux of CO_2 Jiaozhou Bay

LLM4CP:Adapting Large Language Models for Channel Prediction

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Journal of Communications and Information Networks 2024年第2期9卷 113-125页

作者： Boxun Liu Xuanyu Liu Shijian gao Xiang Cheng Liuqing yang State Key Laboratory of Advanced Optical Communication Systems and Networks School of ElectronicsPeking UniversityBeijing 100871China Internet of Things Thrust The Hong Kong University of Science and Technology(Guangzhou)Guangzhou 511400China Internet of Things Thrust and Intelligent Transportation Thrust The Hong Kong University of Science and Technology(Guangzhou)Guangzhou 511400China Department of Electronic and Computer Engineering and Department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyHong KongChina

Channel prediction is an effective approach for reducing the feedback or estimation overhead in massive multi-input multi-output (m-MIMO) systems. However, existing channel prediction methods lack precision due to model mismatch errors or network generalization issues. Large language models (LLMs) have demonstrated powerful modeling and generalization abilities, and have been successfully applied to cross-modal tasks, including the time series analysis. Leveraging the expressive power of LLMs, we propose a pre-trained LLM-empowered channel prediction(LLM4CP)method to predict the future downlink channel state information (CSI) sequence based on the historical uplink CSI sequence. We fine-tune the network while freezing most of the parameters of the pre-trained LLM for better cross-modality knowledge transfer. To bridge the gap between the channel data and the feature space of the LLM,preprocessor, embedding, and output modules are specifically tailored by taking into account unique channel characteristics. Simulations validate that the proposed method achieves state-of-the-art (SOTA) prediction performance on full-sample, few-shot, and generalization tests with low training and inference costs.

关键词： channel prediction massive multi-input multi-output(m-MIMO) large language models(LLMs) fine-tuning time-series

A CHARACTERISTIC SET METHOD FOR SOLVING BOOLEAN EQUATIONS AND APPLICATIONS IN CRYPTANALYSIS OF STREAM CIPHERS

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Journal of Systems Science & Complexity 2008年第2期21卷 191-208页

作者： Fengjuan CHAI Xiao-Shan gao Chunming YUAN Key Laboratory of Mathematics Mechanization Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

This paper presents a characteristic more efficient and has better properties than the set method for solving Boolean equations, which is general characteristic set method. In particular, the authors give a disjoint and monic zero decomposition algorithm for the zero set of a Boolean equation system and an explicit formula for the number of solutions of a Boolean equation system. The authors also prove that a characteristic set can be computed with a polynomial number of multiplications of Boolean polynomials in terms of the number of variables. As experiments, the proposed method is used to solve equations from cryptanalysis of a class of stream ciphers based on nonlinear filter generators. Extensive experiments show that the method is quite effective.

关键词： Boolean equation characteristic set method cryptanalysis finite field stream ciphers.

ON SELF-ABSORPTION CORRECTION IN EXCIMER FLUORESCENCE MEASUREMENTS OF POLYMER SOLUTIONS

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chinese Journal of Polymer Science 2000年第5期18卷 465-468页

作者： Xi-gao Jin Zhong Jiang Ming Ni Feng-lian Bai Ren-yuan Qian Institute of Chemistry, chinese academy of sciences, beijing 100080, china Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

The effect of self absorption on the ratio of excimer to monochromophore emission intensities, I-e/I-m, has been explored by experimentally changing the solution layer thickness of the emission light path traversed in the solution in the right-angle geometry. The result shows that data obtained by front-face geometry are better than those obtained by right-angle geometry even after correction to zero solution thickness. The correction formula based on geometric optics given by Tsai and Torkelson is not adequate.

关键词： excimer fluorescence self absorption polystyrene solution

Acoustofluidics-enhanced biosensing with simultaneously high sensitivity and speed

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Microsystems & Nanoengineering 2024年第3期10卷 335-346页

作者： Yuang Li yang Zhao yang yang Wenchang Zhang Yun Zhang Sheng Sun Lingqian Zhang Mingxiao Li Hang gao Chengjun Huang Institute of Microelectronics of the chinese academy of sciences Beijing 100029P.R.China University of chinese academy of sciences Beijing 101408P.R.China Department of Medicine Brigham and Women’s HospitalHarvard Medical SchoolBostonMA 02115USA

Simultaneously achieving high sensitivity and detection speed with traditional solid-state biosensors is usually limited since the target molecules must passively diffuse to the sensor surface before they can be *** techniques have been applied to shorten the diffusion time by continuously moving molecules through the biosensing ***,the binding efficiencies of the biomolecules are still limited by the inherent laminar flow inside microscale *** this study,focused traveling surface acoustic waves were directed into an acoustic microfluidic chip,which could continuously enrich the target molecules into a constriction zone for immediate detection of the immune reactions,thus significantly improving the detection sensitivity and *** demonstrate the enhancement of biosensing,we first developed an acoustic microfluidic chip integrated with a focused interdigital transducer;this transducer had the ability to capture more than 91%of passed ***,polystyrene microbeads were pre-captured with human IgG molecules at different concentrations and loaded for detection on the *** representative results,~0.63,2.62,11.78,and 19.75 seconds were needed to accumulate significant numbers of microbeads pre-captured with human IgG molecules at concentrations of 100,10,1,and 0.1 ng/mL(~0.7 pM),respectively;this process was faster than the other methods at the hour level and more sensitive than the other methods at the nanomolar *** results indicated that the proposed method could significantly improve both the sensitivity and speed,revealing the importance of selective enrichment strategies for rapid biosensing of rare molecules.

关键词： fluid continuously simultaneous

Entropy of three-dimensional BTZ black holes

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中国科学：物理学、力学、天文学英文版 2004年第3期47卷 277-283页

作者： gao Changjun1,2 & SHEN Yougen1,2,3,4 1.Shanghai Astronomical Observatory,chinese academy of sciences,Shanghai 200030,china(mailing address) 2.National Astronomical Observatories,chinese academy of sciences,beijing 100012,china 3.Institute of Theoretical Physics,chinese academy of sciences,beijing 100080,china 4.Shanghai United Center for Astrophysics,Shanghai 200234,china Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai China National Astronomical Observatories Chinese Academy of Sciences Beijing China Institute of Theoretical Physics Chinese Academy of Sciences Beijing China Shanghai United Center for Astrophysics Shanghai China

The entropies of scalar field and neutrino field are calculated in the background of three-dimensional BTZ black hole. Considering statistical physics,we propose not to consider the superraradiant modes for bosons (Fermion fields do not display supperradiance).In fact,the nonsuperradiant modes do contribute exactly the area entropy for both bosons and fermions. The result shows that the neutrino field entropy is 3/2 times the scalar one.

关键词： BTZ black holes, entropy, supperradiant modes.

Protein lysine crotonylation in cellular processions and disease associations

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Genes & Diseases 2024年第5期11卷 219-235页

作者： Hongling Zhao yang Han Pingkun Zhou Hua Guan Shanshan gao beijing Key Laboratory for Radiobiology Beijing Institute of Radiation MedicineBeijing 100850China

Protein lysine crotonylation(Kcr)is one conserved form of posttranslational modifications of proteins,which plays an important role in a series of cellular physiological and pathological *** e-amino groups are the primary sites of such modification,resulting in four-carbon planar lysine crotonylation that is structurally and functionally distinct from the acetylation of these *** levels of Kcr modifications have been identified on both histone and non-histone *** present review offers an update on the research progression regarding protein Kcr modifications in biomedical contexts and provides a discussion of the mechanisms whereby Kcr modification governs a range of biological *** addition,given the importance of protein Kcr modification in disease onset and progression,the potential viability of Kcr regulators as therapeutic targets is elucidated.

关键词： Cell biology Disease Lysine crotonylation Posttranslational modification Therapeutic target

Difference schemes on non-uniform mesh and their application

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Progress in Natural Science:Materials International 2004年第10期14卷 8-14页

作者： MA Yanwen ,gao Hui,FU Dexun and LI Xinliang (Laboratory of Nonlinear Mechanics,Institute of Mechanics,chinese academy of sciences,beijing100080,china) Lab. of Nonlinear Mech. Inst. of Mech. Chinese Acad. of Sci. Beijing 100080 China

High order accurate schemes are needed to simulate the multi-scale complex flow fields to get fine structures in simula-tion of the complex flows with large gradient of fluid parameters near the wall,and schemes on non-uniform mesh are desirable for many CFD(computational fluid dynamics)*** construction methods of difference approximations and several difference approxima-tions on non-uniform mesh are *** accuracy of the methods and the influence of stretch ratio of the neighbor mesh increment on accuracy are *** comments on these methods are given,and comparison of the accuracy of the results obtained by schemes based on both non-uniform mesh and coordinate transformation is made,and some numerical examples with non-uniform mesh are present-ed.

关键词： scheme on non-uniform mesh high order accurate scheme compact difference approximation

Homogenizing interfacial shear stress in brick-and-mortar structured composites via gradient modulus for enhanced mechanical properties

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Acta Mechanica Sinica 2024年第6期40卷 115-124页

作者： yang gao Jiawei He Jie Jiang Jianping Zuo School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing100083China

Inspired by nature,various biomimetic materials have been synthesized for enhanced mechanical properties,among which composites with brick-and-mortar structures attract the most *** such bio-inspired composites,the matrix layer mainly functions to transfer load between bricks through shearing,while the shear stress in the matrix is not uniform but highly concentrated on the interface ends,which tends to initiate cracks and evoke interface delamination in *** enhance the composites’resistance to interface delamination,we propose to homogenize the shear stress by adopting a matrix with a gradient modulus.A theoretical solution to the optimal gradient modulus of the matrix layer is obtained,followed by computational ***,composites with such functionally graded matrices are further demonstrated to possess higher elastic limits,higher resilience,and flaw tolerance than the uniform *** results of this paper should be of great value to the design and synthesis of advanced structural materials for superior mechanical performance.

关键词： Stress concentration Interface delamination Brick-and-mortar structure Composite