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Robustness and breakup of the spiral wave in a two-dimensional lattice network of neurons

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Science China(physics,Mechanics & Astronomy) 2010年第4期53卷 672-679页

作者： MA Jun 1,2, TANG Jun 2 , ZHANG AiHua 3.& JIA Ya 2 1 department of physics, Lanzhou university of Technology, Lanzhou 73.050, China 2 department of physics, Central China Normal university, Wuhan 43.079, China 3.College of Electrical and Information Engineering, Lanzhou university of Technology, Lanzhou 73.050, China department of physics Lanzhou University of Technology Lanzhou 730050 China

The robustness and breakup of spiral wave in a two-dimensional lattice networks of neurons are investigated. The effect of small- world type connection is often simplified with local regular connection and the long-range connection with certain probability. The network effect on the development of spiral wave can be better described by local regular connection and changeable long-range connection probability than fixed long-range connection probability because the long-range probability could be changeable in realistic biological system. The effect from the changeable probability for long-range connection is simplified by multiplicative noise. At first, a stable rotating spiral wave is developed by using appropriate initial values, parameters and no-flux boundary conditions, and then the effect of networks is investigated. Extensive numerical studies show that spiral wave keeps its alive and robust when the intensity of multiplicative noise is below a certain threshold, otherwise, the breakup of spiral wave occurs. A statistical factor of synchronization in two-dimensional array is defined to study the phase transition of spiral wave by checking the membrane potentials of all neurons corresponding to the critical parameters(the intensity of noise or forcing current)in the curve for factor of synchronization. The Hindmarsh-Rose model is investigated, the Hodgkin-Huxley neuron model in the presence of the channel noise is also studied to check the model independence of our conclusions. And it is found that breakup of spiral wave is easier to be induced by the multiplicative noise in presence of channel noise.

关键词： spiral wave factor of synchronization breakup multiplicative noise robustness

Entangled quantum heat engine based on two-qubit heisenberg XY model

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Chinese physics B 2012年第5期21卷 47-52页

作者：何济洲何弦郑洁 department of physics Nanchang University

Based on a two-qubit isotropic heisenberg XY model under a constant external magnetic field,we construct a four-level entangled quantum heat engine（Qhe）.The expressions for the heat transferred,the work,and the efficiency are ***,the influence of the entanglement on the thermodynamic quantities is investigated analytically and *** interesting features of the variations of the heat transferred,the work,and the efficiency with the concurrences of the thermal entanglement of two different thermal equilibrium states in zero and nonzero magnetic fields are obtained.

关键词： isotropic heisenberg XY model thermal entanglement quantum heat engine perfor-mance characteristics

Progress of International Meridian Circle Program

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空间科学学报 2024年第4期44卷 741-745页

作者： WANG Chi BLANC Michel ZHANG Shunrong DENARDINI Clezio Marcos LIU William SheN Xuhui WU Jian XU Jiyao LI Hui ZHANG Qinghe REN Liwen ZHU Yajun LI {3. DING Zonghua LIU Zhengkuan YANG Fang National Space Science Center Chinese Academy of SciencesBeijing 100190 IRAP(CNRS-university Toulouse III-CNES) Toulouse 31400 Haystack Observatory Massachusetts Institute of TechnologyMA 01886 Instituto Nacional de Pesquisas Espaciais São Josédos Campos(SP)Brazil 12227-010 China Research Institute of Radio wave Propagation Qingdao 266000 Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100083

In 2024,the Chinese Meridian Project(CMP)completed its construction,deploying 282 instruments across 3. *** achievement not only provides a robust foundation but also serves as a reference template for the International Meridian Circle Program(IMCP).The IMCP aims to integrate and establish a comprehensive network of ground-based monitoring stations designed to track the propagation of space weather events from the Sun to ***,it monitors various disturbances generated within the Earth system that impact *** the past two years,significant progress has been made on the *** particular,the second phase of construction for the China-Brazil Joint Laboratory for Space Weather has been completed,and the North Pole and Southeast Asia networks are under active *** 2024 IMCP joint observation campaign was successfully *** facilitate these developments,the scientific program committee of IMCP was established,following the success of 2023.IMCP workshop and the space weather school,which was co-hosted with the Asia-Pacific Space Cooperation Organization(APSCO)and sponsored by Chinese Academy of Sciences(CAS)and Scientific Committee on Solar-Terrestrial physics(SCOSTEP).Preparations are now underway for the 2024 workshop in collaboration with the National Institute for Space Research(INPE)in Brazil.

关键词： Chinese Meridian Project(CMP) International Meridian Circle Program(IMCP) China-Brazil Joint Laboratory for Space Weather North Pole and Southeast Asia networks

The　Dynamic　Behaviour　Analysis　of　Up－Conversion　Luminescence　in　ErP5O14　Glass

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Chinese Journal of Lasers 1995年第1期B4卷 73-80页

作者： CheN Jinkai CheN Xiaobo HUANG Zhiwei YANG Wenqing(Experiment Center,Fujian Normal university, Fuzhou 3.0007,China {3. department,{3.,Tian jing 3.0071,China) Fujian Normal Univ Fuzhou China

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关键词： ErP5O(14) glass up-conversion three photon luminescence

Stationary Classical Chaos of Trapped Two-Component Bose-Einstein Condensates in 1-D Optical Lattice Potentials

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Communications in Theoretical physics 2007年第7期48卷 125-131页

作者： FANG Jian-Shu LIU Wing-Ki ZHU Shan-Hua1 Institute of physics,Hunan university of Technology,Zhuzhou 412008,China2 department of physics,Hunan Normal university,Changsha 410081,China3.department of physics,university of Waterloo,Waterloo,Ontario,Canada N2L 3.1 Institute of physics Hunan University of Technology Zhuzhou 412008 China

We study the nonlinear dynamics of two-component Bose-Einstein condensates in one-dimensional pe-riodic optical lattice *** stationary state perturbation solutions of the coupled two-component nonlinearSchr?dinger/Gross-Pitaevskii equations are constructed by using the direct perturbation *** analysisrevels that the perturbation solution is the chaotic one,which indicates the existence of chaos and chaotic region inparameter *** corresponding numerical calculation results agree well with the analytical *** applying thechaotic perturbation solution,we demonstrate the atomic spatial population and the energy distribution of the systemare chaotic generally.

关键词： stationary state classical chaos two-component Bose-Einstein condensates optical lattice potential

Pairwise entanglement and local polarization of heisenberg model

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Science China(physics,Mechanics & Astronomy) 2008年第10期51卷 1515-1522页

作者： XI XiaoQiang1,2, ZHANG Tao3. YUE RuiHong3.4 & LIU WuMing2 1 department of Applied Mathematics and physics, Xi’an Institute of Post and Telecommunications, Xi’an 710061, China 2 Beijing National Laboratory for Condensed Matter physics, Institute of physics, Chinese Academy of Sciences, Beijing 100080, China 3.Institute of Modern physics, Northwest university, Xi’an 710069, China 4 department of physics, Ningbo university, Ningbo 3.5211, China department of Applied Mathematics and physics Xi’an Institute of Post and Telecommunications Xi’an China Beijing National Laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing China Institute of Modern physics Northwest University Xi’an China department of physics Ningbo University Ningbo China

The characteristics of pairwise entanglement and local polarization (LP) are dis-cussed by studying the ground state (states) of the heisenberg XX model. The re-sults show that: the ground state (states) is (are) composed of the micro states with the minimal polarization (0 for even qubit and 1/2 for odd qubit); LP and the prob-ability of the micro state have an intimate relation, i.e. the stronger the LP, the smaller the probability, and the same LP corresponds to the same probability; the pairwise entanglement of the ground state is the biggest in all eigenvectors. It is found that the pairwise entanglement is decreased by the state degeneracy and the system size. The concurrence approaches a fixed value of about 0.3.12 (for odd-qubit chain) or 0.3.91 (for even-qubit chain) if the qubit number is large enough.

关键词： heisenberg XX model local polarization pairwise entanglement

The Ambient Gas Effects on Pulsed Laser Ablation of Target

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光电子·激光 1996年第1期7卷 12-15页

作者： Gongtang Wang Xiangtai Wang Baoyuan Mian(department of physics,Shandong Normal university,Jinan 250014)Bingzhang Xu Liangmo Mei(department of physics.Shandong university,Jinan 250100) 山东师范大学物理系山东济南山东大学物理系山东济南

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关键词： Al￣+ ion mean projected range laser ablation ambient gas effect.

A Deep Learning Framework for Mass-Forming Chronic Pancreatitis and Pancreatic Ductal Adenocarcinoma Classification Based on Magnetic Resonance Imaging

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Computers, Materials & Continua 2024年第4期79卷 409-427页

作者： Luda Chen Kuangzhu Bao Ying Chen Jingang Hao Jianfeng he Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming650504China department of Radiology Second Affiliated Hospital of Kunming Medical UniversityKunming650101China School of physics and Electronic Engineering Yuxi Normal UniversityYuxi653100China

Pancreatic diseases, including mass-forming chronic pancreatitis (MFCP) and pancreatic ductal adenocarcinoma(PDAC), present with similar imaging features, leading to diagnostic complexities. Deep Learning (DL) methodshave been shown to perform well on diagnostic tasks. Existing DL pancreatic lesion diagnosis studies basedon Magnetic Resonance Imaging (MRI) utilize the prior information to guide models to focus on the lesionregion. However, over-reliance on prior information may ignore the background information that is helpful fordiagnosis. This study verifies the diagnostic significance of the background information using a clinical ***, the Prior Difference Guidance Network (PDGNet) is proposed, merging decoupled lesion andbackground information via the Prior Normalization Fusion (PNF) strategy and the Feature Difference Guidance(FDG) module, to direct the model to concentrate on beneficial regions for diagnosis. Extensive experiments inthe clinical dataset demonstrate that the proposed method achieves promising diagnosis performance: PDGNetsbased on conventional networks record an ACC (Accuracy) and AUC (Area Under the Curve) of 87.50% and89.98%, marking improvements of 8.19% and 7.64% over the prior-free benchmark. Compared to lesion-focusedbenchmarks, the uplift is 6.14% and 6.02%. PDGNets based on advanced networks reach an ACC and AUC of89.77% and 92.80%. The study underscores the potential of harnessing background information in medical imagediagnosis, suggesting a more holistic view for future research.

关键词： Pancreatic cancer pancreatitis background region prior normalization fusion feature difference guidance

Spontaneous chiral-symmetry breaking of lattice QCD with massless dynamical quarks

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Science China(physics,Mechanics & Astronomy) 2007年第1期50卷 6-14页

作者： LUO XiangQian department of physics,School of physics and Engineering,Sun Yat-Sen {3.,Guangzhou 510275,China department of physics School of Physics and Engineering Sun Yat-Sen University Guangzhou 510275 China

One of the most challenging issues in QCD is the investigation of spontaneous chiral-symmetry breaking, which is characterized by the non-vanishing chiral condensate when the bare fermion mass is zero. In standard methods of the lattice gauge theory, one has to perform expensive simulations at multiple bare quark masses, and employ some modeled functions to extrapolate the data to the chiral limit. This paper applies the probability distribution function method to computing the chiral condensate in lattice QCD with massless dynamical quarks, without any ambiguous mass extrapolation. The results for staggered quarks indicate that this might be a promising and efficient method for investigating the spontaneous chiral-symmetry breaking in lattice QCD, which deserves further investigation.

关键词： lattice QCD spontaneous chiral-symmetry breaking dynamical quarks