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Acta Metallurgica Sinica(English Letters) 1999年第3期12卷 216-220页

作者： J. Guo (department of physics, guangxi university, nanning 530004, china) guangxi Univ Nanning China

The artificial neural network method has been applied to the relationship between the atomic parameters and intemction packeters of binary alloy Phases, and the principle of thermodynamics in combination with artificial neural network method has been used for the computerized phase diagrams of continuous solid solution of bigamy alloy systems. The computerized phase diagrams well agree with the real phase diagmms.

关键词： antificial neural network interaction parameter computerized phase diagram

Quantum self-attention neural networks for text classification

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Science china(Information Sciences) 2024年第4期67卷 301-313页

作者： guangxi LI Xuanqiang ZHAO Xin WANG Institute for Quantum Computing Baidu Research Centre for Quantum Software and Information University of Technology Sydney QICI Quantum Information and Computation Initiative Department of Computer ScienceThe University of Hong Kong Thrust of Artificial Intelligence Information HubHong Kong University of Science and Technology(Guangzhou)

An emerging direction of quantum computing is to establish meaningful quantum applications in various fields of artificial intelligence, including natural language processing(NLP). Although some efforts based on syntactic analysis have opened the door to research in quantum NLP(QNLP), limitations such as heavy syntactic preprocessing and syntax-dependent network architecture make them impracticable on larger and real-world data sets. In this paper, we propose a new simple network architecture, called the quantum selfattention neural network(QSANN), which can compensate for these limitations. Specifically, we introduce the self-attention mechanism into quantum neural networks and then utilize a Gaussian projected quantum self-attention serving as a sensible quantum version of self-attention. As a result, QSANN is effective and scalable on larger data sets and has the desirable property of being implementable on near-term quantum devices. In particular, our QSANN outperforms the best existing QNLP model based on syntactic analysis as well as a simple classical self-attention neural network in numerical experiments of text classification tasks on public data sets. We further show that our method exhibits robustness to low-level quantum noises and showcases resilience to quantum neural network architectures.

关键词： quantum neural networks self-attention natural language processing text classification parameterized quantum circuits

Correlation between pulse-width and peak luminosity of single-pulse long gamma-ray bursts

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Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 69-72页

作者： DENG JiaGan & LIANG EnWei department of physics,guangxi university,nanning 530004,china department of physics Guangxi University Nanning China

With a sample of 21 single-pulse GRBs with redshift measurement and a sample of 65 single-pulse GRBs with pseudo redshift estimated by the luminosity-spectral lag relation,we show that the peak luminosities of GRB pulses are anti-correlated with pulse width,indicating that longer-pulses tend to be dimmer in the gamma-ray *** anti-correlation is accessible with an internal shock scenario.

关键词： gamma-rays:bursts-gamma-rays:observations

X-ray flares of γ-ray bursts: Quakes of solid quark stars?

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Science china(physics,Mechanics & Astronomy) 2009年第2期52卷 315-320页

作者： XU RenXin1 & LIANG EnWei2 1 School of physics and State Key Laboratory of Nuclear physics and Technology, Peking university, Beijing 100871, china 2.department of physics, guangxi university, nanning 530004, china School of physics and State Key Laboratory of Nuclear physics and Technology Peking University Beijing China department of physics Guangxi University Nanning China

A star-quake model is proposed to understand X-ray flares of both long and short γ-ray bursts (GRBs) in a solid quark star regime. Two kinds of central engines for GRBs are available if pulsar-like stars are actually (solid) quark stars, i.e., the SNE-type GRBs and the SGR-type GRBs. It is found that a quark star could be solidified about 103 to 106 s later after its birth if the critical temperature of phase transi- tion is a few Metga-electron-volts, and then a new source of free energy (i.e., elastic and gravitational ones, rather than rotational or magnetic energy) could be possible to power GRB X-ray flares.

关键词： γ-rays bursts: X-rays neutron stars elementary particles

Spectral properties of Fermi/GBM gamma-ray bursts and the GeV emission detection rate with Fermi/LAT

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Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 73-77页

作者： LV HouJun,LIANG EnWei & TONG XiaoFeng department of physics,guangxi university,nanning 530004,china department of physics Guangxi University Nanning China

With a sample of 58 Fermi/GBM GRBs detected before 2009 May,we compare the spectral properties of GBM GRBs with those detected by CGRO/BTASE and *** results show that the spectral index distributions are very consistent with those observed by ***,the Ep distribution is quite different from that observed with BATSE and *** GBM GRBs tend to be softer than the BATSE sample,but harder than the HETE-2 *** may be due to the instrumental selection effects and artificial sample effect on the BATSE *** distribution of the pseudo redshifts derived from the luminosity indicator based on the Amati-relation shows rough consistency with the spectroscopic redshifts of Swift *** estimate the detection rate of GBM GRBs with LAT based on the observed spectrum in the GBM band,and the inferred burst ratio of LAT detection with over 5 photons to GBM detection is 6%,yielding a detection rate pf 12 GRBs/yr with over 5 photons in the 1-300 GeV *** is roughly consistent with the results in the first half year of Fermi *** low detection rate compared with theoretical predictions is a key for revealing the radiation mechanisms and particle acceleration of the prompt gamma-rays.

关键词： gamma-ray bursts high energy phenomenon spectrum statistics

Multiwavelet sampling theorem in Sobolev spaces

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Science china Mathematics 2010年第12期53卷 3197-3214页

作者： LI YouFa 1,2 & YANG ShouZhi 1, 1 department of Mathematics, Shantou university, Shantou 515063, china 2 College of Mathematics and Information Sciences, guangxi university, nanning 530004, china department of Mathematics Shantou University Shantou China College of Mathematics and Information Sciences Guangxi University Nanning China

This paper is to establish the multiwavelet sampling theorem in Sobolev spaces. Sampling theorem plays a very important role in digital signal communication. The most classical sampling theorem is Shannon sampling theorem, which works for bandlimited signals. Recently, sampling theorems in wavelets or multiwavelets subspaces are extensively studied in the literature. In this paper, we firstly propose the concept of dual multiwavelet frames in dual Sobolev spaces (H s (R) , H-s (R)). Then we construct a special class of dual multiwavelet frames, from which the multiwavelet sampling theorem in Sobolev spaces is obtained. That is, for any f ∈ H s (R) with s > 1/2, it can be exactly recovered by its samples. Especially, the sampling theorem works for continuous signals in L 2 (R), whose Sobolev exponents are greater than 1 /2.

关键词： Sobolev spaces refinable function vectors dual multiwavelet frames delta function sampling theorem

Luminosity-peak energy relation in the decay phases of gamma-ray burst pulses

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Science china(physics,Mechanics & Astronomy) 2010年第1期53卷 163-170页

作者： LU RuiJing & LIANG EnWei Physical Science & Technology College, guangxi university, nanning 530004, china Physical Science & Technology College Guangxi University Nanning China

Using time-resolved spectral data for a sample of 30 pulses in 27 bright GRBs detected with CGRO/BATSE, we investigate the luminosity-peak energy relation (L-E p relation) in the decay phases of these pulses. A tight L-E p relation is found for most of the pulses, but its power law index is various among pulses, which is normally distributed at 1.84±0.60(1σ) for the pulses in our sample, roughly consistent with the L-E p relation within a GRB and the isotropic gamma-ray energy-E p relation among GRBs. The large scatter of the power law index cannot be explained with both the statistical or observational effects and it may be an intrinsic feature, indicating that no universal L-E p relation would be expected among GRBs/pulses. This may strongly weaken the cosmological use of this relation.

关键词： gamma ray bursts observations statistical luminosity-peak energy relation

Dynamic Modeling of Key Operating Parameters for Supercritical Circulating Fluidized Bed Units based on Data-Knowledge-Driven Method

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Journal of Thermal Science 2024年第3期33卷 1216-1230页

作者： YU Haoyang GAO Mingming ZHANG Hongfu CHEN Jiyu LIU Jizhen YUE guangxi The State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources School of Control and Computer EngineeringNorth China Electric Power UniversityBeijing102206China CHN Energy New Energy Technology Research Institute Co. Ltd.Beijing102209China department of Energy and Power Engineering Tsinghua UniversityBeijing100084China

To address the pressing need for intelligent and efficient control of circulating fluidized bed(CFB)units,it is crucial to develop a dynamic model for the key operating parameters of supercritical circulating fluidized bed(SCFB)***,data-knowledge-driven dynamic model of bed temperature,load,and main steam pressure of the SCFB unit has been ***,a knowledge-driven method is employed to develop a dynamic model for key operating parameters of SCFB *** model parameters are determined based on the operating data of the unit and continuously optimized in real ***,Bidirectional Long Short-Term Memory combined with Convolutional Neural Network and Attention Mechanism is utilized to build the dynamic model of bed temperature,load,and main steam ***,a collaboration and integration method based on the critic weight method and the variation coefficient method is proposed to establish data-knowledge-driven model of key operating parameters for SCFB *** model displays great accuracy and fitting ability compared with other methods and effectively captures the dynamic characteristics,which can provide a research basis for the design of intelligent flexible control mode of SCFB unit.

关键词： circulating fluidized bed dynamic model data-knowledge-driven method deep learning power plant

Gamma-ray bursts in the Swift-Fermi era:Confronting data with theory

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Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 14-23页

作者： LIANG EnWei Physical Science & Technology College,guangxi university,nanning 530004,china Physical Science & Technology College Guangxi University Nanning China

With the prompt slewing capability of the X-ray and UV-optical telescopes onboard the Swift mission and with the gamma-ray large area telescope onboard the Fermi mission,gamma-ray bursts(GRBs) are now accessible in a full time window and in all electromagnetic wavelengths for the *** observational breakthroughs have been made in recent years.I present here a brief review of some observational breakthroughs with the two missions,focusing on how these breakthroughs have revolutionized our understanding of the nature of this phenomenon and puzzles as well as challenges of confronting the conventional models with data.

关键词： radiation mechanism gamma rays bursts high energy phenomenon

Bubble dynamics properties of B-particles in a quasi-2D gas-solid fluidized bed:Computational particle fluid dynamics numerical simulation and post-processed by digital image analysis technique

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Particuology 2024年第3期86卷 223-238页

作者： Zemin Yuan Zhong Huang Guotao Qin Guanjia Zhao Suxia Ma Hairui Yang guangxi Yue Key Laboratory of Clean and Efficient Combustion and Utilization in the Circulating Fluidized Bed Taiyuan University ofTechnologyTaiyuan030024China department of Energy and Power Engineering Tsinghua UniversityBeijing100084.China

Bubble dynamics properties play a crucial and significant role in the design and optimization of gas-solid fluidized *** this study,the bubble dynamics properties of four B-particles were investigated in a quasi-two-dimensional(quasi-2D)fluidized bed,including bubble equivalent diameter,bubble size distribution,average bubble density,bubble aspect ratio,bubble hold-up,bed expansion ratio,bubble radial position,and bubble *** studies were performed by computational particle fluid dynamics(CPFD)numerical simulation and post-processed with digital image analysis(DIA)technique,at superficial gas velocities ranging from 2u_(mf) to 7u_(mf).The simulated results shown that the CPFD simulation combining with DIA technique post-processing could be used as a reliable method for simulating bubble dynamics properties in quasi-2D gas-solid fluidized ***,it seemed not desirable for the simulation of bubble motion near the air distributor at higher superficial gas velocity from the simulated average bubble density *** superficial gas velocity significantly affected the bubble equivalent diameter and evolution,while it had little influence on bubble size distribution and bubble aspect ratio distribution for the same *** time-averaged bubble hold-up and bed expansion ratio increased with the increase of superficial gas *** core-annular flow structures could be found in the fluidized bed for all *** average bubble rising velocity increased with the increasing bubble equivalent *** bubble lateral movement,the smaller bubbles might be more susceptible,and superficial gas velocity had a little influence on the absolute lateral velocity of *** simulated results presented a valuable and novel approach for studying bubble dynamics *** comprehensive understanding of bubble dynamics behaviors in quasi-2D gas-solid fluidized beds would provide support in the design,operation,and optimization of gas-solid

关键词： Bubble dynamics properties CPFD simulation Quasi-2D gas-solid fluidized bed Digital image analysis