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STABILITY OF SVIR SYSTEM WITH RANDOM PERTURBATIONS

International Journal of Biomathematics 2012年第4期5卷 97-111页

作者： CHAO DENG HONGJUN GAO Jiangsu Provincial Key Laboratory for Numerical Simulation of Large Scale Complex Systems School of Mathematical Sciences Nanjing Normal University Nanjing 210046 P. R. China

In this paper, the SVIR epidemic models with continuous vaccination strategies investi- gated by Liu, Takeuchi and Iwamo, [SVIR epidemic models with vaccination strategies, J. Theor. Biol. 253 （2008） 1 11], allowing random fluctuation around the endemic equi- librium and the transmission rate t3 are analyzed. The equilibrium state of the model with random perturbation is locally asymptotically stable as shown by a Lyapunov stability analysis.

关键词： Local asymptotic stability SVIR model Lyapunov function white noise.

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QQqq in a chiral constituent quark model

arXiv

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arXiv 2020年

作者： Tan, Yue Lu, Weichang Ping, Jialun Dept. of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China

Inspired by Ξccreported by LHCb Collaboration and X(5568) reported by D0 Collaboration, the QQqq (Q = c, b, q = u, d) tetraquark states, are studied in the present work. With the help of Gaussian expansion method, two structures, diquark-antiquark and meson-meson, with all possible color configurations are investigated systematically in a chiral quark model to search for the possible stable states. The results show that there is no bound state in the isovector QQqq system, while there are rather deep bound states in the isoscalar bbqq, ccqq and bcqq systems. Mixing two structures of diquark-antidiquark and meson-meson can introduce more attractions and convert some unbound isoscalar states into shallow bound states. The large mass of the heavy quark is beneficial to the formation of the bound state. The separations between quarks are calculated to unravel the spacial structure of the system. Copyright © 2020, The Authors. All rights reserved.

关键词： Hadrons

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Triply charm and bottom tetraquarks in a constituent quark model

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Physical Review D 2024年第5期110卷 054036页

作者： Gang Yang Jialun Ping Jorge Segovia Department of Physics Department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Departamento de Sistemas Físicos Químicos y Naturales

Singly, doubly, and fully charmed tetraquark candidates, e.g., Tcs¯(2900), Tcc+(3875), and X(6900) have been recently reported by the LHCb collaboration. Therefore, it is timely to implement a theoretical investigation on triply heavy tetraquark systems; herein, the S-wave triply charm and bottom tetraquarks, Q¯Qq¯Q (q=u,d,s;Q=c,b), with spin-parity JP=0+, 1+, and 2+, isospin I=0 and 12, are systematically studied in a constituent quark model. Besides, all tetraquark configurations, i.e., meson-meson, diquark-antidiquark, and K-type arrangements, along with any allowed color structure, are comprehensively considered. The Gaussian expansion method (GEM), in combination with the complex-scaling method (CSM), which is quite ingenious in dealing with either bound or resonances, is the approach adopted in solving the complex scaled Schrödinger equation. This theoretical framework has already been applied in various tetra- and pentaquark systems. In a fully coupled-channel calculation within the GEM+CSM, narrow resonances are found in each I(JP) channel of the charm and bottom sector. In particular, triply charm and bottom tetraquark resonances are obtained in 5.6–5.9 GeV and 15.3–15.7 GeV, respectively. We provide also some insights of the compositeness of these exotic states, such as the inner quark distance, magnetic moment and dominant wave function component. All this may help to distinguish them in future high energy nuclear and particle experiments.

关键词： Multiquark bound states Quantum chromodynamics Quark model Strong interaction

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Impacts of major volcanic eruptions over the past two millennia on both global and Chinese climates:A review

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Science China Earth Sciences 2024年第1期67卷 61-78页

作者： Weiyi SUN Deliang CHEN Guonian LÜ Liang NING Chaochao GAO Renhe ZHANG Bin WANG Jian LIU Key Laboratory for Virtual Geographic Environment Ministry of EducationState Key Laboratory Cultivation Base of Geographical Environment Evolution of Jiangsu ProvinceJiangsu Center for Collaborative Innovation in Geographical Information Resource Development and ApplicationSchool of Geography ScienceNanjing Normal UniversityNanjing 210023China Regional Climate Group Department of Earth SciencesUniversity of GothenburgGothenburg 40530Sweden College of Environmental and Resource Science Zhejiang UniversityHangzhou 310058China Department of Atmospheric and Oceanic Sciences&Institute of Atmospheric Sciences Fudan UniversityShanghai 200437China Department of Atmospheric Sciences and Atmosphere-Ocean Research Center University of Hawaii at ManoaHonoluluHI 96825USA Jiangsu Provincial Key Laboratory for Numerical Simulation of Large Scale Complex Systems School of Mathematical ScienceNanjing Normal UniversityNanjing 210023China Open Studio for the Simulation of Ocean-Climate-Isotope Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China

Major volcanic eruptions(MVEs)have attracted increasing attention from the scientific *** studies have explored the climatic impact of MVEs over the past two ***,proxy-based reconstructions and climate model simulations indicate divergent responses of global and China’s regional climates to ***,we used multiple data from observations,reconstructions,simulations,and assimilations to summarize the historical facts of MVEs,the characteristics and mechanisms of their climatic impact,and directions for future *** reviewed volcanic datasets and determined intensive MVE periods;these periods corresponded to the years 530–700,1200‒1460,and 1600‒1840 *** tropical MVEs,a substantial cooling effect is observed throughout the globe and China on the interannual-interdecadal time scales but an inconsistent cooling magnitude is detected between reconstructions and *** the first summer after tropical MVEs,a decrease in global and monsoonal precipitation is *** reconstructions and simulations,an increased precipitation is seen for the Yangtze River Basin,while large uncertainties in precipitation changes are present for other regions of *** drought can be induced by frequent eruptions and volcanism superimposed on low solar irradiation and internal *** affect climate directly through the radiative effect and indirectly by modulating internal variability,such as the El Niño‒Southern Oscillation(ENSO)and Atlantic Multidecadal Oscillation(AMO).However,changes in the phase,amplitude,and periodicity of ENSO and AMO after MVEs and the associated mechanisms remain controversial,which could account for model-reconstruction ***,other internal variability,uncertainties in reconstruction methods and aerosol‒climate models,and climate background may also induce model-reconstruction *** gaps and directions for future research are also discussed.

关键词： Major volcanic eruption Climate variability Mechanism Past two millennia Internal variability

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Strength of the North African monsoon in the Last Interglacial and under future warming

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Atmospheric and Oceanic Science Letters 2023年第3期16卷 20-26页

作者： Jiazhi He Weiyi Sun Jing Wang Bin Wang Jian Liu Key Laboratory for Virtual Geographic Environment Ministry of EducationState Key Laboratory Cultivation Base of Geographical Environment Evolution of Jiangsu ProvinceJiangsu Center for Collaborative Innovation in Geographical Information Resource Development and ApplicationSchool of Geography ScienceNanjing Normal UniversityNanjingChina Department of Atmospheric Sciences and AtmosphereOcean Research Center University of Hawaii at ManoaHonoluluHIUA Jiangsu Provincial Key Laboratory for Numerical Simulation of Large Scale Complex Systems School of Mathematical ScienceNanjing Normal UniversityNanjingChina Open Studioforthe Simulationof Ocean-Climate-Isotope Qingdao National Laboratoryfor Marine Science and TechnologyQingdaoChina

与人为强迫引起的全球变暖相比,末次间冰期是轨道强迫引起的过去80万年来最暖的一个间冰期,但鲜有人研究末次间冰期中北非季风的响应.因此,本文基于CMIP6多模式模拟结果对比研究了末次间冰期和SSP5-8.5情景下北非季风的响应,发现末次间... 详细信息

与人为强迫引起的全球变暖相比,末次间冰期是轨道强迫引起的过去80万年来最暖的一个间冰期,但鲜有人研究末次间冰期中北非季风的响应.因此,本文基于CMIP6多模式模拟结果对比研究了末次间冰期和SSP5-8.5情景下北非季风的响应,发现末次间冰期下北非季风平均降水及其降水变率均远大于SSP5-8.5情景下的结果.轨道强迫导致的北大西洋暖于南大西洋增加了北非季风环流和平均降水,同时,南北大西洋海温梯度变化通过增强热带北大西洋的海气相互作用增大了海温梯度和撒哈拉低压的变率,从而增强了北非季风降水变率.

关键词：北非季风降水变率末次间冰期全球变暖

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Triply heavy baryons in the constituent quark model

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Chinese Physics C 2020年第2期44卷 33-41页

作者： Gang Yang Jialun Ping Pablo GOrtega Jorge Segovia Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics Tsinghua UniversityBeijing 100084China Department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal UniversityNanjing 210023China Grupo de Física Nuclear and Instituto Universitario de Física Fundamental y Matemáticas(IUFFyM) Universidad de SalamancaE-37008 SalamancaSpain Departamento de Sistemas Físicos Químicos y NaturalesUniversidad Pablo de OlavideE-41013 SevillaSpain

The constituent quark model is used to compute the ground and excited state masses of QQQ baryons containing either c or b *** quark model parameters previously used to describe the properties of charmonium and bottomonium states were used in this *** non-relativistic three-body bound state problem is solved by means of the Gaussian expansion method which provides sufficient accuracy and simplifies the subsequent evaluation of the matrix *** low-lying states with quantum numbers J^P=1/2^±,3/2^±,5/2^±and 7/2^+are *** compare the results with those obtained by the other theoretical *** is a general agreement for the mass of the ground state in each sector of triply heavy ***,the situation is more puzzling for the excited states,and appropriate comments about the most relevant features of our comparison are given.

关键词： Quantum Chromodynamics quark models properties of baryons exotic baryons

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The S- and P-wave low-lying baryons in the chiral quark model

arXiv

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arXiv 2017年

作者： Yang, Gang Ping, Jialun Segovia, Jorge Department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China E-08193 Spain

The 1S, 2S, 1P and 2P states of light baryons are investigated within the chiral quark model, paying particular attention to the well-known order reverse problem of 1P and 2S states. Besides a nonperturbative linearscreened confining interaction and a perturbative one-gluon exchange between quarks, we incorporate the Goldstone-boson exchanges taking into account not only the full octet of pseudoscalar mesons but also the scalar one. The scalar meson exchange potential simulates the higher order multi-pion exchange terms that appear in the chiral Lagrangian and its omission has been already admitted as a deficiency of the original model in describing, for instance, the π - w splitting. The numerical approach to the three-body bound state problem is the so-called Gaußian expansion method, which is able to get a precision as good as Faddeev calculations. With a set of parameters fixed to different hadron and hadron-hadron observables, we find that the chiral potential could play an important role towards the issue on the mass order reverse problem. We extend our calculation to the qqQ and qQQ sectors (with q representing a light u-, d-, or s-quark and Q denoting the charm quark or the bottom one) in which many new states have been recently observed. Some tentative assignments are done attending to the agreement between theoretical and experimental masses;however, we admit that other sources of information are needed in order to make strong claims about the nature of these states. Copyright © 2017, The Authors. All rights reserved.

关键词： Hadrons

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Investigating the excited Ωc0 states through ΞcK¯ and Ξc′K¯ decay channels

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Physical Review D 2018年第3期97卷 034027-034027页

作者： Hongxia Huang Jialun Ping Fan Wang Department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing 210023 China Department of Physics Nanjing University Nanjing 210093 China

Inspired by the five newly observed Ωc0 states by the LHCb detector, we study the Ωc0 states as the S-wave molecular pentaquarks with I=0, JP=12−, 32−, and 52− by solving the renormalization group method equation in the framework of the chiral quark model. Both the energies and the decay widths are obtained in this work. Our results suggest that Ωc(3119)0 can be explained as an S-wave resonance state of ΞD with JP=12−, and the decay channels are the S-wave ΞcK¯ and Ξc′K¯. Other reported Ωc0 states cannot be obtained in our present calculation. Another Ωc0 state with much higher mass 3533 MeV with JP=52− is also obtained. In addition, the calculation is extended to the Ωb0 states, and results similar to those of Ωc0 are obtained.

关键词： Hadron-hadron interactions Quark model

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Clifford algebra-based spatio-temporal modelling and analysis for complex geo-simulation data

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AIP Conference Proceedings 2013年第1期1558卷 542-545页

作者： Wen Luo Zhaoyuan Yu Yong Hu Linwang Yuan Key Laboratory of Virtual Geographic Environment Ministry of Education Nanjing Normal University No.1 Wenyuan Road Nanjing China Key Laboratory of Virtual Geographic Environment Ministry of Education Nanjing Normal University No.1 Wenyuan Road Nanjing China and Jiangsu Provincial Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal Univer China

The spatio-temporal data simulating Ice-Land-Ocean interaction of Antarctic are used to demonstrate the Clifford algebra-based data model construction, spatio-temporal query and data analysis. The results suggest that Clifford algebra provides a powerful mathematical tool for the whole modelling and analysis chains for complex geo-simulation data. It can also help implement spatio-temporal analysis algorithms more clearly and simply.

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simulation of Centennial-scale Drought Events over Eastern China during the Past 1500 Years

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Journal of Meteorological Research 2017年第1期31卷 17-27页

作者： Weiyi SUN Jian LIU Zhiyuan WANG key laboratory for virtual geographic environment(nanjing normal university) ministry of educationstate key laboratory cultivation base of geographical environment evolution(jiangsu province)School of Geography ScienceNanjing Normal UniversityNanjing 210023 Jiangsu Provincial Key Laboratory for Numerical Simulation of Large Scale Complex Systems School of Mathematical ScienceNanjing Normal UniversityNanjing 210023 Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023

The characteristics and causes of centennial-scale drought events over eastern China during the past 1500 years were explored based on simulations of the Community Earth System Model （CESM）. The results show that centenni- al-scale drought events over eastern China occurred during the periods of 622-735 （Drought period 1, D1） and 1420-1516 （Drought period 2, D2） over the past 1500 years, which is comparable with climate proxy data. In D1, the drought center occurred in northern China and the Yangtze River valley; however, in southern China, precipitation was much more than usual. In D2, decreased precipitation was found across almost the whole region of eastern China. The direct cause of these two drought events was the weakened East Asian summer monsoon, and the specif- ic process was closely linked to the air-sea interaction of the Indo-Pacific Ocean. In DI, regions of maximum cool- ing were observed over the western Pacific, which may have led to anomalous subsidence, weakening the Walker cir- culation, and reducing the northward transport of water vapor. Additionally, upward motion occurred over southern China, strengthening convection and increasing precipitation. In D2, owing to the decrease in the SST, subsidence dominated the North Indian Ocean, blocking the low-level cross-equatorial flow, enhancing the tropical westerly an- omalies, and reducing the northward transport of moisture. Additionally, descending motion appeared in eastern China, subsequently decreasing the precipitation over the whole region of eastern China. The anomalous cooling of the Indo-Pacific Ocean SST may have been caused by the persistently low solar irradiation in D1; whereas, in D2, this characteristic may have been influenced not only by persistently low solar irradiation, but frequent volcanic erup- tions too.

关键词： CESM centennial-scale drought eastern China East Asian summer monsoon

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