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Evaluating the AS-level Internet models:beyond topological characteristics

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Chinese Physics B 2012年第2期21卷 591-595页

作者： Fan zheng-ping Department of Automation Sun Yat-Sen UniversityGuangzhou 510275China

A surge number of models has been proposed to model the Internet in the past decades. However, the issue on which models are better to model the Internet has still remained a problem. By analysing the evolving dynamics of the Internet, we suggest that at the autonomous system （AS） level, a suitable Internet model, should at least be heterogeneous and have a linearly growing mechanism. More importantly, we show that the roles of topological characteristics in evaluating and differentiating Internet models are apparently over-estimated from an engineering perspective. Also, we find that an assortative network is not necessarily more robust than a disassortative network and that a smaller average shortest path length does not necessarily mean a higher robustness, which is different from the previous observations. Our analytic results are helpful not only for the Internet, but also for other general complex networks.

关键词： AS-level Internet scale-free model robustness

Design of a Transverse-flux Permanent-magnet Linear Generator and Controller for Use with a Free-piston Stirling Engine

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Chinese Journal of Mechanical Engineering 2016年第4期29卷 832-842页

作者： zheng Jigui HUANG Yuping WU Hongxing zheng ping Electrical Engineering & Automation Department Harbin Institute of Technology Harbin 150001 China Beijing Research Institute of Precise Mechatronic Controls Beijing 100076 China

Transverse-flux with high efficiency has been applied in Stirling engine and permanent magnet synchronous linear generator system,however it is restricted for large application because of low and complex process.A novel type of cylindrical,non-overlapping,transverse-flux,and permanent-magnet linear motor（TFPLM） is investigated,furthermore,a high power factor and less process complexity structure research is *** impact of magnetic leakage factor on power factor is discussed,by using the Finite Element Analysis（FEA） model of stirling engine and TFPLM,an optimization method for electro-magnetic design of TFPLM is proposed based on magnetic leakage *** relation between power factor and structure parameter is investigated,and a structure parameter optimization method is proposed taking power factor maximum as a *** last,the test bench is founded,starting experimental and generating experimental are performed,and a good agreement of simulation and experimental is *** power factor is improved and the process complexity is *** research provides the instruction to design high-power factor permanent-magnet linear generator.

关键词： permanent-magnet linear motor(TFPLM) stirling engine magnetic leakage factor power factor

DYNAMICS OF α AND α' RELAXATION IN LAYERED SILICATE/POLYSTYRENE NANOCOMPOSITES STUDIED BY ANELASTIC SPECTROSCOPY

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Chinese Journal of Polymer Science 2013年第10期31卷 1334-1342页

作者： Shu-ying Shang zheng-ping Fang Institute of Polymer Composites Zhejiang University College of Physics & Information Engineering Henan Normal University Laboratory of Polymer Materials and Engineering Ningbo Institute of Technology Zhejiang University

The dynamics of polymer chains in layered silicate/polystyrene nanocomposites was studied by anelastic spectroscopy. Two thermal activated peaks （or and α＇ peaks） appeared when the specimens were heated to a high temperature and they were related to glass transition and liquid-liquid transition, respectively. The activation energy was calculated based on Arrhenius equation and it showed that the activation energy of glass transition （Eg） is much higher than that of liquid-liquid transition （EH）. Furthermore, the most interesting result for the activation energy was that there were two contrary trends for Eg and Ell, Eg decreased and Ell increased with the addition of clay platelets. The fragile parameter was analyzed and the variation of fragile parameters for the two transitions was also contrary to each other with the addition of clay platelets. All the results indicated that the confinement effect of clay platelets on the dynamics of polymer chain was scale dependent, and perhaps, the two transitions were produced by different mechanisms.

关键词： Dynamics Glass transiton Liquid-liquid transition Composites Confinement.

Self-Trapping of Three-Dimensional Spatiotemporal Solitary Waves in Self-Focusing Kerr Media

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Chinese Physics Letters 2012年第6期29卷 166-168页

作者： YANG zheng-ping ZHONG Wei-ping Department of Medical Science Shunde PolytechnicShunde 528300 Department of Electronic and Information Engineering Shunde PolytechnicShunde 528300

We theoretically demonstrate that Kerr media under self-focusing nonlinearity support three-dimensional spatiotemporal solitary waves in various patterns,such as necklace-,disk-,and vortex-ring *** structures of these... 详细信息

关键词： nonlinearity vortex solitary

The neuroscience of pain,addiction,and anesthesia

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Zoological Research 2024年第3期45卷 709-710页

作者： Ji Hu ping zheng School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China State Key Laboratory of Medical Neurobiology Institutes of Brain ScienceMOE Frontier Center for Brain ScienceDepartment of Neurology of Zhongshan HospitalFudan UniversityShanghai 200032China

Researchers and clinicians have long been interested in the mechanisms of pain,anesthesia,and *** International Association for the Study of Pain(IASP)defines pain as an unpleasant sensory and emotional experience associated with,or resembling that associated with,actual or potential tissue damage(Raja et al.,2020).Drug addiction refers to a condition of reliance that develops from regular drug consumption,which may lead to withdrawal symptoms when use is *** involves the complete loss of consciousness induced by an inhaled or intravenous anesthetic(Tosello et al.,2022).In this special collection,Zoological Research presents research findings focused on pain,addiction,and anesthesia.

关键词： anesthesia damage

Uniqueness and Radial Symmetry of Least Energy Solution for a Semilinear Neumann Problem

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Acta Mathematicae Applicatae Sinica 2008年第3期24卷 473-482页

作者： zheng-ping Wang Huan-song Zhou Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences P.O.Box 71010 Wuhan 430071 China

Consider the following Neumann problem d△u- u ＋ k（x）u^p = 0 and u 〉 0 in B1, δu/δv =0 on OB1,where d 〉 0, B1 is the unit ball in R^N, k（x） = k（｜x｜） ≠ 0 is nonnegative and in C（-↑B1）, 1 〈 p 〈 N＋2/N-2 with N≥ 3. It was shown in [2] that, for any d 〉 0, problem （＊） has no nonconstant radially symmetric least energy solution if k（x） ≡ 1. By an implicit function theorem we prove that there is d0 〉 0 such that （＊） has a unique radially symmetric least energy solution if d 〉 d0, this solution is constant if k（x） ≡ 1 and nonconstant if k（x） ≠ 1. In particular, for k（x） ≡ 1, do can be expressed explicitly.

关键词： Implicit function theorem least energy solution radial symmetry Neumann problem elliptic

Observational Constraints on Quark Matter in Neutron Stars

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Chinese Journal of Astronomy and Astrophysics 2007年第5期7卷 675-684页

作者： Na-Na Pan Xiao-ping zheng Institute of Astrophysics Huazhong Normal University Wuhan 430079

We study the observational constraints of mass and redshift on the properties of the equation of state （EOS） for quark matter in compact stars based on the quasi-particle description. We discuss two scenarios; strange stars and hybrid stars. We construct the equations of state utilizing an extended MIT bag model taking the medium effect into account for quark matter and the relativistic mean field theory for hadron matter. We show that quark matter may exist in strange stars and in the interior of neutron stars. The bag constant is a key parameter that affects strongly the mass of strange stars. The medium effect can lead to the stiffer hybrid-star EOS approaching the pure hadronic EOS, due to the reduction of quark matter, and hence the existence of heavy hybrid stars. We find that a middle range coupling constant may be the best choice for the hybrid stars being compatible with the observational constraints.

关键词： dense matter -- gravitation -- stars neutron -- stars rotation -- stars oscillations

Macroscopic Quantum Coherence in an Antiferromagnetic Spin Chain with Biaxial Anisotropy

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Communications in Theoretical Physics 2009年第8期52卷 365-368页

作者： ZHAO Qun-Chao zheng Gong-ping WANG zheng Department of Physics Henan Normal University Xinxiang 453007 China Department of Physics and Information Engineering Shangqiu Normal Univeristy Shangqiu 476000 China

Instanton configurations of （1＋1）-dimensions in an antiferromagnetic biaxial-anisotropy-spin-chain are obtained explicitly in the strong anisotropy limit, which interpolate between degenerate equilibrium orientations of the Neel vector along easy axis and are seen to be responsible for quantum tunneling. Macroscopic quantum coherence of the domain walls is demonstrated in terms of the instantons.

关键词： macroscopic quantum coherence antiferromagnetic spin chain

Therapeutic plasma exchange for hyperlipidemic pancreatitis:Current evidence and unmet needs

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World Journal of Clinical Cases 2021年第21期9卷 5794-5803页

作者： Can-Bin zheng Zi-Hui zheng Yong-ping zheng Department of Endocrine and Metabolic Disease Shantou Central HospitalShantou 515031Guangdong ProvinceChina Nursing College Guangdong Pharmaceutical UniversityGuangzhou 510000Guangdong ProvinceChina Department of Gastroenterology Shantou Central HospitalShantou 515031Guangdong ProvinceChina

With changes in lifestyle and diet worldwide,the prevalence of hyperlipidemic acute pancreatitis(HLAP)has greatly increased,and it has become the most common cause of acute pancreatitis not due to gallstones or *** are many available therapies for HLAP,including oral lipid-lowering agents,intravenous insulin,heparin,and therapeutic plasmapheresis(TPE).It is believed that the risk and severity of HLAP increase with rising levels of serum triglycerides(TG),thus a rapid decrease in serum TG level is the key to the successful management of *** has emerged as an effective modality in rapidly reducing serum TG ***,due to its cost and accessibility,TPE remains poorly evaluated until *** studies revealed its efficacy in helping to treat and prevent the recurrence,while some studies suggested that TG levels were not correlated with disease severity,mortality,or length of hospital *** TPE might have no beneficial effect for the *** article gives an overview of the published evidence of TPE in the treatment of HLAP and outlines current evidence regarding individual outcome predictors,adverse effects of the procedure,and TPE in special occasions such as for pregnant patients and patients with diabetic *** direction of TPE research for HLAP is also discussed in this review.

关键词： Therapeutic plasma exchange Hyperlipidemic acute pancreatitis Evidence Outcome Future direction