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Development of a new cerebral ischemia reperfusion model of Mongolian gerbils and standardized evaluation system 被引量:3
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作者 Ying Wu Caijiao Hu +9 位作者 Zhihui Li Feiyang Li Jianyi Lv Meng Guo Xin Liu Changlong Li Xueyun Huo Zhenwen Chen Lifeng Yang Xiaoyan Du 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第1期48-55,共8页
Background:The Mongolian gerbil is an excellent laboratory animal for preparing the cerebral ischemia model due to its inherent deficiency in the circle of Willis.However,the low incidence and unpredictability of symp... Background:The Mongolian gerbil is an excellent laboratory animal for preparing the cerebral ischemia model due to its inherent deficiency in the circle of Willis.However,the low incidence and unpredictability of symptoms are caused by numerous complex variant types of the circle.Additionally,the lack of an evaluation system for the cer-ebral ischemia/reperfusion(I/R)model of gerbils has shackled the application of this model.Methods:We created a symptom-oriented principle and detailed neurobehavioral scoring criteria.At different time points of reperfusion,we analyzed the alteration in locomotion by rotarod test and grip force score,infarct volume by triphenyltetrazo-lium chloride(TTC)staining,neuron loss using Nissl staining,and histological charac-teristics using hematoxylin-eosin(H&E)straining.Results:With a successful model rate of 56%,32 of the 57 gerbils operated by our method harbored typical features of cerebral I/R injury,and the mortality rate in the male gerbils was significantly higher than that in the female gerbils.The suc-cessfully prepared I/R gerbils demonstrated a significant reduction in motility and grip strength at 1 day after reperfusion;formed obvious infarction;exhibited typi-cal pathological features,such as tissue edema,neuronal atrophy and death,and vacuolated structures;and were partially recovered with the extension of reperfu-sion time.Conclusion:This study developed a new method for the unilateral common carotid artery ligation I/R model of gerbil and established a standardized evaluation system for this model,which could provide a new cerebral I/R model of gerbils with more practical applications. 展开更多
关键词 ISCHEMIA/REPERFUSION Mongolian gerbil standardized model system unilateral carotid occlusion
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Toward Analytical Homogenized Relaxation Modulus for Fibrous Composite Material with Reduced Order Homogenization Method
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作者 Huilin Jia Shanqiao Huang Zifeng Yuan 《Computers, Materials & Continua》 SCIE EI 2025年第1期193-222,共30页
In this manuscript,we propose an analytical equivalent linear viscoelastic constitutive model for fiber-reinforced composites,bypassing general computational homogenization.The method is based on the reduced-order hom... In this manuscript,we propose an analytical equivalent linear viscoelastic constitutive model for fiber-reinforced composites,bypassing general computational homogenization.The method is based on the reduced-order homogenization(ROH)approach.The ROH method typically involves solving multiple finite element problems under periodic conditions to evaluate elastic strain and eigenstrain influence functions in an‘off-line’stage,which offers substantial cost savings compared to direct computational homogenization methods.Due to the unique structure of the fibrous unit cell,“off-line”stage calculation can be eliminated by influence functions obtained analytically.Introducing the standard solid model to the ROH method enables the creation of a comprehensive analytical homogeneous viscoelastic constitutive model.This method treats fibrous composite materials as homogeneous,anisotropic viscoelastic materials,significantly reducing computational time due to its analytical nature.This approach also enables precise determination of a homogenized anisotropic relaxation modulus and accurate capture of various viscoelastic responses under different loading conditions.Three sets of numerical examples,including unit cell tests,three-point beam bending tests,and torsion tests,are given to demonstrate the predictive performance of the homogenized viscoelastic model.Furthermore,the model is validated against experimental measurements,confirming its accuracy and reliability. 展开更多
关键词 Homogenized relaxation modulus VISCOELASTIC standard solid model reduced order homogenization fibrous composite material
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3D Quantum Gravity, Localization and Particles beyond Standard Model
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作者 Risto Raitio 《Journal of High Energy Physics, Gravitation and Cosmology》 2025年第1期96-109,共14页
We review a 3d quantum gravity model, which incorporates massive spinning fields into the Euclidean path integral in a Chern-Simons formulation. Fundamental matter as defined in our previous preon model is recapped. B... We review a 3d quantum gravity model, which incorporates massive spinning fields into the Euclidean path integral in a Chern-Simons formulation. Fundamental matter as defined in our previous preon model is recapped. Both quantum gravity and the particle model are shown to be derivable from the supersymmetric 3d Chern-Simons action. Forces-Matter unification is achieved. 展开更多
关键词 Chern-Simons Theory Quantum Gravity Composite Particles Beyond Standard Model
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Gravitational waves from patterns of electroweak symmetry breaking:an effective perspective
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作者 Rong-Gen Cai Katsuya Hashino +1 位作者 Shao-Jiang Wang Jiang-Hao Yu 《Communications in Theoretical Physics》 2025年第5期93-117,共25页
The future space-borne gravitational wave(GW)detectors would provide a promising probe for the new physics beyond the standard model that admits the first-order phase transitions.The predictions for the GW background ... The future space-borne gravitational wave(GW)detectors would provide a promising probe for the new physics beyond the standard model that admits the first-order phase transitions.The predictions for the GW background vary sensitively among different concrete particle physics models but also share a large degeneracy in the model buildings,which motivates an effective model description on the phase transition based on different patterns of the electroweak symmetry breaking(EWSB).In this paper,using the scalar N-plet model as a demonstration,we propose an effective classification for three different patterns of EWSB:(1)radiative symmetry breaking with classical scale invariance,(2)the Higgs mechanism in a generic scalar extension,and(3)higher-dimensional operators.We conclude that a strong first-order phase transition could be realized for(1)and(2)with a small quartic coupling and a small isospin of an additional N-plet field for the light scalar field model with and without the classical scale invariance,and(3)with a large mixing coupling between scalar fields and a large isospin of the N-plet field for the heavy scalar field model. 展开更多
关键词 first-order phase transition gravitational wave standard model effective field theory
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Research of database-based modeling for mining management system
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作者 武海峰 金智新 白希军 《Journal of Coal Science & Engineering(China)》 2005年第1期98-101,共4页
Put forward the method to construct the simulation model automatically with database-based automatic modeling(DBAM) for mining system. Designed the standard simulation model linked with some open cut Pautomobile dispa... Put forward the method to construct the simulation model automatically with database-based automatic modeling(DBAM) for mining system. Designed the standard simulation model linked with some open cut Pautomobile dispatch system. Analyzed and finded out the law among them, and designed model maker to realize the automatic pro- gramming of the new model program. 展开更多
关键词 automatic modeling DBAM standard model model maker
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On capped Higgs positivity cone
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作者 Dong-Yu Hong Zhuo-Hui Wang Shuang-Yong Zhou 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第7期44-54,43,I0003,共13页
The Wilson coefficients of the standard model effective field theory are subject to a series of positivity bounds.It has been shown that while the positivity part of the ultraviolet(UV)partial wave unitarity leads to ... The Wilson coefficients of the standard model effective field theory are subject to a series of positivity bounds.It has been shown that while the positivity part of the ultraviolet(UV)partial wave unitarity leads to the Wilson coefficients living in a convex cone,further including the nonpositivity part caps the cone from above.For Higgs scattering,a capped positivity cone was obtained using a simplified,linear unitarity condition without utilizing the full internal symmetries of Higgs scattering.Here,we further implement stronger nonlinear unitarity conditions from the UV,which generically gives rise to better bounds.We show that,for the Higgs case in particular,while the nonlinear unitarity conditions per se do not enhance the bounds,the fuller use of the internal symmetries do shrink the capped positivity cone significantly. 展开更多
关键词 positivity bounds standard model effective field theory(SMEFT) HIGGS
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Spatiotemporal patterns and drivers of cultivated land conversion in Inner Mongolia Autonomous Region,northern China
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作者 Xijiri ZHOU Ruiping +1 位作者 BAO Baorong Burenjirigala 《Journal of Arid Land》 SCIE CSCD 2024年第9期1197-1213,共17页
Protection and optimization of cultivated land resources are of great significance to national food security.Cultivated land conversion in northern China has increased in recent years due to the industrialization and ... Protection and optimization of cultivated land resources are of great significance to national food security.Cultivated land conversion in northern China has increased in recent years due to the industrialization and urbanization of society.However,the assessment of cultivated land conversion in this area is insufficient,posing a potential risk to cultivated land resources.This study evaluated the evolution and spatiotemporal patterns of cultivated land conversion in Inner Mongolia Autonomous Region,China,and the driving factors to improve rational utilization and to protect cultivated land resources.The spatiotemporal patterns of cultivated land conversion in Inner Mongolia were analyzed using the cultivated land conversion index,kernel density analysis,a standard deviation ellipse model,and a geographic detector.Results showed that from 2000 to 2020,the trends in cultivated land conversion area and rate in Inner Mongolia exhibited fluctuating growth,with the total area of cultivated land conversion reaching 7307.59 km^(2) at a rate of 6.69%.Spatial distribution of cultivated land conversion was primarily concentrated in the Hetao Plain,Nengjiang Plain,Liaohe Plain,and the Hohhot-Baotou-Ordos urban agglomeration.Moreover,the standard deviational ellipse of cultivated land conversion in Inner Mongolia exhibited a directional southwest-northeast-southwest-northeast distribution,with the northeast-southwest direction identified as the main driving force of spatial change in cultivated land conversion.Meanwhile,cultivated land conversion exhibited an increase-decrease-increase change process,indicating that spatial distribution of cultivated land conversion in Inner Mongolia became gradually apparent within the study period.The geographic detector results further revealed that the main driving factors of cultivated land conversion in Inner Mongolia were the share of secondary and tertiary industries and per-unit area yield of grain,with explanatory rates of 57.00%,55.00%,and 51.00%,respectively.Additionally,improved agricultural production efficiency and the coordinated development of population urbanization and industry resulted in cultivated land conversion.Collectively,the findings of this study indicated that,from 2000 to 2020,the cultivated land conversion in Inner Mongolia was significant and fluctuated in time,and had strong spatial heterogeneity.The primary drivers of these events included the effects of agriculture,population,and social economy. 展开更多
关键词 cultivated land conversion spatiotemporal variation standard deviation elliptical models geographic detector northern China
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Structural Foundation and Geometry of the Material Singularity (and Its Quantum Entanglement)
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作者 Rafael Cañete Mesa 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1095-1137,共43页
In this paper we develop and study, as the second part of one more general development, the energy transmutation equation for the material singularity, previously obtained through the symmetrisation of a wave packet, ... In this paper we develop and study, as the second part of one more general development, the energy transmutation equation for the material singularity, previously obtained through the symmetrisation of a wave packet, that is, we develop the correlation between the terms of this equation, which accounts for the formation of matter from a previous vibrational state, and the different possible energy species. These energetic species are ascribed, in a simplified form, to the equation E¯ω=E¯k+E¯f, which allows us, through its associated phase factor, to gain an insight into the wave character of the kinetic energy and thus to attain the basis of the matter-wave, and all sorts of related phenomenologies, including that concerning quantum entanglement. The formation of the matter was previously identified as an energetic process, analogous to the kinetic one, in which finally the inertial mass is consolidated as a mass in a different phase, now, in addition, the mass of the material singularity is identified as a volumetric density of waves of toroidal geometry created in the process of singularisation or energy transfer between species, which makes it possible to establish the real relation or correspondence between the corpuscular and photonic energy equation (E=mc2=hν), i.e. to explain through m the intimate sense of the first equivalence, which explains what νis in the second one. 展开更多
关键词 Standard Model WAVE-PACKET Material Singularity Wave-Particle Dualism Wave Symmetrisation Matter-Wave Energetic Transmutation Quantum Entanglement
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On the Possible Structures of Electron and Proton
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作者 Wei-Xing Xu 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1734-1742,共9页
In this work, the possible structures of electron and proton have been explored. Based on the potential expressions of electron and proton, we found that the electron and proton share the similar structure inside re a... In this work, the possible structures of electron and proton have been explored. Based on the potential expressions of electron and proton, we found that the electron and proton share the similar structure inside re and rn. And within re and rn, the conventional charge concept stops working, the same charge repelling force doesn’t exist anymore and as a result, the requirement of charge conservation is automatically removed. Whereas beyond re and rn, the potential expressions of electron and proton obey the point charge potentials as we normally understand. Therefore, the conventional charge concept can be applied and the requirement of charge conservation takes effect. Furthermore, a possible mechanism for the creations of electric monopole and magnetic monopole is discussed. In addition, to compare the particle size in micro-world, the balloon criterion is proposed. By this balloon criterion, the proton is determined about 10 times bigger than electron. From the physical picture about electron and proton described above, the stabilities of electron and proton can be explained quite well. 展开更多
关键词 Electromagnetic Spacetime Quantum Mechanics ELECTRON PROTON Standard Model Particle Physics “Yin-Yang” Philosophy Electric Monopole Magnetic Monopole Charge Conservation
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Towards 6D Little String Theory of Particles
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作者 Risto Raitio 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期546-561,共16页
A model for particles based on preons in chiral, vector and tensor/graviton supermultiplets of unbroken global supersymmetry is engineered. The framework of the model is little string theory. Phenomenological predicti... A model for particles based on preons in chiral, vector and tensor/graviton supermultiplets of unbroken global supersymmetry is engineered. The framework of the model is little string theory. Phenomenological predictions are discussed. 展开更多
关键词 Standard Model Composite Models SUPERSYMMETRY Little String Theory T-DUALITY HOLOGRAPHY
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Non-Uniform Pion Tetrahedron Aether and Electron Tetrahedron Model
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作者 Rami Rom 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期810-824,共15页
We propose that the QCD vacuum pion tetrahedron condensate density vary in space and drops to extremely low values in the Kennan, Barger and Cowie (KBC) void in analogy to earth’s atmospheric density drop with elevat... We propose that the QCD vacuum pion tetrahedron condensate density vary in space and drops to extremely low values in the Kennan, Barger and Cowie (KBC) void in analogy to earth’s atmospheric density drop with elevation from earth. We propose a formula for the gravitation acceleration based on the non-uniform pion tetrahedron condensate. Gravity may be due to the underlying microscopic attraction between quarks and antiquarks, which are part of the vacuum pion tetrahedron condensate. We propose an electron tetrahedron model, where electrons are comprised of tetraquark tetrahedrons, and . The quarks determine the negative electron charge and the or quarks determine the electron two spin states. The electron tetrahedron may perform a high frequency quark exchange reactions with the pion tetrahedron condensate by tunneling through the condensation gap creating a delocalized electron cloud with a fixed spin. The pion tetrahedron may act as a QCD glue bonding electron pairs in atoms and molecules and protons to neutrons in the nuclei. Conservation of valence quarks and antiquarks is proposed. 展开更多
关键词 Standard Model (SM) QCD Vacuum Condensate Electric Dipole Moment (EDM) KBC Void ANTIMATTER MOND Theory Aether
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Estimates of the Charges and Size of the Three Types of Neutrinos
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作者 Ardeshir Irani 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1467-1469,共3页
It is the current belief of the Physics Community that neutrinos are bereft of Charge because of Conservation of Charge in decay processes such as Beta Decay and are point particles with no physical size or shape. It ... It is the current belief of the Physics Community that neutrinos are bereft of Charge because of Conservation of Charge in decay processes such as Beta Decay and are point particles with no physical size or shape. It is the purpose of this paper to calculate the charges and the size of the electron neutrino, the muon neutrino, and the tau neutrino based on data available of their rest masses using the charges and rest masses of the electron, muon, and tau leptons from the Standard Model of Particle Physics Table. We base our calculations on the premise that Energy can create both Mass and Charge. Charge by itself is not conserved in any process that produces neutrinos. Only Total Energy is conserved. 展开更多
关键词 Electron Neutrino Muon Neutrino Tau Neutrino Standard Model of Particle Physics Beta Decay Total Energy
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Constraints on Asymmetric Dark Matter in Quintessence Model
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作者 Sujuan Qiu Hoernisa Iminniyaz 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期599-608,共10页
The modified cosmology like quintessence model with kination phase predicted the Hubble expansion rate of the universe before Big Bang Nucleosynthesis is different from the standard cosmological scenario. The modified... The modified cosmology like quintessence model with kination phase predicted the Hubble expansion rate of the universe before Big Bang Nucleosynthesis is different from the standard cosmological scenario. The modified expansion rate leaves its imprint on the relic density of asymmetric dark matter. In this work, we review the calculation of relic density of asymmetric WIMP dark matter in the standard cosmological scenario and quintessence model with kination phase. Then we use the Planck data to find constraints on the annihilation cross section and the mass of the asymmetric dark matter in those models. 展开更多
关键词 Asymmetric Dark Matter Standard Model Quintessence Model
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An Investigation of the Harmonic Quark with an Energy-Mass Quantum of 253.4 GeV and How It Relates to the Heavy Particles of the Standard Model
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作者 Hongguang Yang Weidong Yang 《Journal of Modern Physics》 2024年第13期2347-2364,共18页
The understanding of the mechanism for the mass building of elementary particles of Standard Model (SM) has made significant progresses since the confirmation of the existence of the Higgs boson, in particular the rea... The understanding of the mechanism for the mass building of elementary particles of Standard Model (SM) has made significant progresses since the confirmation of the existence of the Higgs boson, in particular the realization that the mass of an elementary particle of SM is not “God-given” but is created by interactions with involved energy fields. Nevertheless, a sophisticated model to answer fundamental questions is still missing. Further research is needed to compensate for the existing deficit. The current paper is aimed to contribute to such research by using “harmonic quark series”. Harmonic quark series were introduced between 2003 and 2005 by O. A. Teplov and represented a relatively new approach to understanding the physical masses of elementary particles. Although they are not generally recognized, some research works have revealed very interesting and exciting facts regarding the mass quanta. The original harmonic quark series consists of mathematical “quark” entities with an energy-mass quantum between 7.87 MeV and 69.2 GeV. They obey a strict mathematical rule derived from the general harmonic oscillation theory. Teplov showed some quantitative relations between the masses of his harmonic quarks and the SM particles, especially in the intermediate mass range, i.e. mesons and hadrons up to 1000 MeV. Early research work also includes the investigation of H. Yang/W. Yang in the development of their so-called YY model for elementary particles (Ying-Yang model with “Ying” and “Yang” as quark components for a new theoretical particle framework). Based on Teplov’s scheme and its mathematical formula, they introduced further harmonic quarks down to 1 eV and showed some quantitative relationships between the masses of these harmonic quarks and the masses of electrons and up and down quarks. In this article, we will extend the harmonic quark series according to the Teplov scheme up to a new entity with a mass quantum of 253.4 GeV and show some interesting new mass relations to the heavy particles of the Standard Model (W boson, Z boson, top quark and Higgs boson). Based on these facts, some predictions will be made for experimental verification. We also hope that our investigation and result will motivate more researcher to dedicate their work to harmonic quark series in theory and in experiments. 展开更多
关键词 Harmonic Quark Series Teplov Mass Formula YY Model for Atomic Kernel Standard Model Particles MESONS W-BOSON Z-Boson Top Quark Higgs Boson
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Calculation of the Standard Model Parameters and Particles Based on a SU(4) Preon Model
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作者 Jan Helm 《Journal of Modern Physics》 2024年第1期64-124,共61页
This paper describes an extension and a new foundation of the Standard Model of particle physics based on a SU(4)-force called hyper-color, and on preon subparticles. The hyper-color force is a generalization of the S... This paper describes an extension and a new foundation of the Standard Model of particle physics based on a SU(4)-force called hyper-color, and on preon subparticles. The hyper-color force is a generalization of the SU(2)-based weak interaction and the SU(1)-based right-chiral self-interaction, in which the W-and the Z-bosons are Yukawa residual-field-carriers of the hyper-color force, in the same sense as the pions are the residual-field-carriers of the color SU(3) interaction. Using the method of numerical minimization of the SU(4)-action based on this model, the masses and the inner structure of leptons, quarks and weak bosons are calculated: the mass results are very close to the experimental values. We calculate also precisely the value of the Cabibbo angle, so the mixing matrices of the Standard model, CKM matrix for quarks and PMNS matrix for neutrinos can also be calculated. In total, we reduce the 29 parameters of the Standard Model to a total of 7 parameters. 展开更多
关键词 SU(4) Generalization of Weak Interaction Extension of Standard Model Numerical Minimization of Action Hyper-Color Preon
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Calculation of Particle Decay Times in the Standard Model
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作者 Jan Helm 《Journal of Modern Physics》 2024年第3期271-321,共51页
We present here a two-step method of classification and calculation for decay rates in the Standard Model. The first step is a phenomenological classification method, which is an extended and improved schematic experi... We present here a two-step method of classification and calculation for decay rates in the Standard Model. The first step is a phenomenological classification method, which is an extended and improved schematic experimental formula for decay width originally introduced by Chang. This schematic formula separates decays into seven classes. Furthermore, from it is derived a process-specific interaction energy m<sub>X</sub>. The second step is a numerical calculation method, which calculates this interaction energy m<sub>X</sub> numerically by minimization of action from the Lagrangian of the process, from which follows the decay width via the phenomenological formula. The Lagrangian is based on an extension of the Standard Model, the extended SU(4)-preon-model. A comparison of numerically calculated and observed decay widths for a large selection of decays shows a good agreement. 展开更多
关键词 Particle Decay Decay Width Interaction Energy Minimization of Action Ex-tension of Standard Model
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Design and transition characteristics of a standard model for hypersonic boundary layer transition research 被引量:9
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作者 Shenshen Liu Xianxu Yuan +5 位作者 Zhiyong Liu Qiang Yang Guohua Tu Xi Chen Yewei Gui Jianqiang Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2021年第11期1637-1647,I0002,共12页
To understand fundamental problems in hypersonic laminar-turbulent boundary layer transition for three-dimensional complex vehicles,a new standard model with typical lifting-body features has been proposed,named as hy... To understand fundamental problems in hypersonic laminar-turbulent boundary layer transition for three-dimensional complex vehicles,a new standard model with typical lifting-body features has been proposed,named as hypersonic transition research vehicle(HyTRV).The configuration of HyTRV is fully analytical,and details of the design process are discussed in this study.The transition characteristics for HyTRV are investigated using three combined methods,i.e.,theoretical analyses,numerical simulations,and wind tunnel experiments.Results show that the fully analytic parameterization design of HyTRV can satisfy the model simplification requirements from both numerical simulations and wind tunnel experiments.Meanwhile,the flow field of HyTRV reveals typical transition mechanisms in six relatively separated regions,including the streamwise vortex instability,crossflow instability,secondary instability,and attachment-line instability.Therefore,the proposed HyTRV model is valuable for fundamental researches in hypersonic boundary layer transition. 展开更多
关键词 Hypersonic boundary layer Transition research Standard model design HyTRV
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Van der Waals interactions and Photoelectric Effect in Noncommutative Quantum Mechanics 被引量:5
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作者 李康 CHAMOUN Nidal 《Chinese Physics Letters》 SCIE CAS CSCD 2007年第5期1183-1186,共4页
We calculate the long-range Van der Waals force and the photoelectric cross section in a noncommutative setup. It is argued that non-commutativity effects could not be discerned for the Van der Waals interactions. The... We calculate the long-range Van der Waals force and the photoelectric cross section in a noncommutative setup. It is argued that non-commutativity effects could not be discerned for the Van der Waals interactions. The result for the photoelectric effect shows deviation from the usual commutative one, which in principle can be used to put bounds on the space-space non-commutativity parameter. 展开更多
关键词 HYDROGEN-ATOM SPECTRUM STANDARD MODEL GAUGE-THEORY FIELD-THEORY PHASE-SPACE BRANE TIME
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Stationarity Intervals of Time-Variant Channel in High Speed Railway Scenario 被引量:16
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作者 Chen Binghao Zhong Zhangdui Ai Bo 《China Communications》 SCIE CSCD 2012年第8期64-70,共7页
The non-stationary behavior, caused by the train rmverrent, is the rmin factor for the variation of high speed railway channel. To measure the tirce-variant effect, the parameter of stationarity interval, in which the... The non-stationary behavior, caused by the train rmverrent, is the rmin factor for the variation of high speed railway channel. To measure the tirce-variant effect, the parameter of stationarity interval, in which the channel keeps constant or has no great change, is adopted based on Zhengzfiou- Xi'an (Zhengxi) passenger dedicated line measurement with different train speeds. The stationarity interval is calculated through the definition of Local Region of Stationarity (LRS) under three train ve- locities. Furthermore, the time non-stationary characteristic of high speed pared with five standard railway channel is corn- Multiple-Input MultipleOutput (MIMO) channel models, i.e. Spatial Channel Model (SCM), extended version of SCM (SCME), Wireless World Initiative New Radio Phase II (WINNERII), International Mobile Teleconmnications-Advanced (IMT-Advanced) and WiMAX models which contain the high speed moving scenario. The stationarity interval of real channel is 9 ms in 80% of the cases, which is shorter than those of the standard models. Hence the real channel of high speed railway changes more rapidly. The stationarity intervals of standard models are different due to different modeling methods and scenario def- initions. And the compared results are instructive for wireless system design in high speed railway. 展开更多
关键词 channel characterization time-variantcharacteristic stationarity interval high speed railway standard MIMO channel model
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Attribute-Based Re-Encryption Scheme in the Standard Model 被引量:4
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作者 GUO Shanqing ZENG Yingpei +1 位作者 WEI Juan XU Qiuliang 《Wuhan University Journal of Natural Sciences》 CAS 2008年第5期621-625,共5页
In this paper, we propose a new attribute-based proxy re-encryption scheme, where a semi-trusted proxy, with some additional information, can transform a ciphertext under a set of attributes into a new ciphertext unde... In this paper, we propose a new attribute-based proxy re-encryption scheme, where a semi-trusted proxy, with some additional information, can transform a ciphertext under a set of attributes into a new ciphertext under another set of attributes on the same message, but not vice versa, furthermore, its security was proved in the standard model based on decisional bilinear Diffie-Hellman assumption. This scheme can be used to realize fine-grained selectively sharing of encrypted data, but the general proxy rencryption scheme severely can not do it, so the proposed schemecan be thought as an improvement of general traditional proxy re-encryption scheme. 展开更多
关键词 ATTRIBUTE-BASED re-encryption scheme standard model network storage
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