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MINIMAL FOLIATIONS FOR THE HIGH-DIMENSIONAL FRENKEL-KONTOROVA MODEL
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作者 缪雪晴 葛建华 +1 位作者 秦文新 王亚南 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期564-582,共19页
For the high-dimensional Frenkel-Kontorova(FK)model on lattices,we study the existence of minimal foliations by depinning force.We introduce the tilted gradient flow and define the depinning force as the critical valu... For the high-dimensional Frenkel-Kontorova(FK)model on lattices,we study the existence of minimal foliations by depinning force.We introduce the tilted gradient flow and define the depinning force as the critical value of the external force under which the average velocity of the system is zero.Then,the depinning force can be used as the criterion for the existence of minimal foliations for the FK model on a Z^(d)lattice for d>1. 展开更多
关键词 Aubry-Mather theory Frenkel-Kontorova model minimal foliation depinning force gradient flow
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Formation of Foliations and their Related Minerals from Diagenetic to Medium-grade Metamorphic Rocks:A Case Study of the Hongyanjing and Liao-Ji Backarc Basins,China 被引量:1
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作者 TIAN Zhonghua WEN Fei +2 位作者 LIU Fulai ZHU Haozhong YE Zhanghuang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第4期1158-1170,共13页
Deciphering the relationship between polyphase tectonic foliations and their associated mineral assemblages is significant in understanding the process from diagenesis to low-/medium-/high-grade metamorphism.It can pr... Deciphering the relationship between polyphase tectonic foliations and their associated mineral assemblages is significant in understanding the process from diagenesis to low-/medium-/high-grade metamorphism.It can provide information related to strain,metamorphic conditions and overprinting relationships and so help reveal the tectonic evolution of orogenesis.In this study,we predominately focus on the formation of foliations and their related minerals,as developed in two separate basins.First of all,two stages of axial plane cleavages(S1 and S2)were recognized in the Hongyanjing inter-arc basin,the formation of the S1 axial plane cleavage is associated with mica rotation and elongation in mudstones in the local area.The pencil structure of S2 formed during the refolding phase,the minerals in the sedimentary rocks not changing their shape and orientation.Secondly,in the Liao-Ji backarc basin,foliations include diagenetic foliation(bedding parallel foliation),tectonic S1 foliation(secondary foliation or axial plane cleavage of S0 folding)and crenulation cleavage(S2).The formation mechanism of foliation changes from mineral rotation or elongation and mineral solution transfer in S1 to crystal-plastic deformation,dynamic recrystallization and micro-folding in S2.Many index metamorphic minerals formed from low-grade to medium-grade consist of biotites,garnets,staurolite and kyanite,constituting a typical Barrovian metamorphic belt.Accordingly,a new classification of foliation is presented in this study.The foliations can be divided into continuous and disjunctive foliations,based on the existence of microlithons,detectable with the aid of a microscope.Disjunctive foliation can be further sub-divided into spaced foliation and crenulation cleavage,according to whether(or not)crenulation(micro-folding)is present.The size of the mineral grains is also significant for classification of the foliations. 展开更多
关键词 new classification of foliations mineral transformation OROGENESIS Hongyanjing basin Liao-Ji backarc basin
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A Note on Totally Real Riemannian Foliations with Parallelized Mean Curvature Vectors in a Complex Projective Space
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作者 PENG Hui-chun 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第3期410-414,共5页
We discussed a totally real Riemannian foliations with parallel mean curvature on a complex projective space.We carried out the divergence of a vector field on it and obtained a formula of Simons’type.
关键词 Riemannian foliations complex projective space mean curvature DIVERGENCE
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Anisotropic shearing mechanism of Kangding slate:Experimental investigation and numerical analysis 被引量:1
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作者 Ping Liu Quansheng Liu +4 位作者 Penghai Deng Yucong Pan Yiming Lei Chenglei Du Xianqi Xie 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1487-1504,共18页
The shear mechanical behavior is regarded as an essential factor affecting the stability of the surrounding rocks in underground engineering.The shear strength and failure mechanisms of layered rock are significantly ... The shear mechanical behavior is regarded as an essential factor affecting the stability of the surrounding rocks in underground engineering.The shear strength and failure mechanisms of layered rock are significantly affected by the foliation angles.Direct shear tests were conducted on cubic slate samples with foliation angles of 0°,30°,45°,60°,and 90°.The effect of foliation angles on failure patterns,acoustic emission(AE)characteristics,and shear strength parameters was analyzed.Based on AE characteristics,the slate failure process could be divided into four stages:quiet period,step-like increasing period,dramatic increasing period,and remission period.A new empirical expression of cohesion for layered rock was proposed,which was compared with linear and sinusoidal cohesion expressions based on the results made by this paper and previous experiments.The comparative analysis demonstrated that the new expression has better prediction ability than other expressions.The proposed empirical equation was used for direct shear simulations with the combined finite-discrete element method(FDEM),and it was found to align well with the experimental results.Considering both computational efficiency and accuracy,it was recommended to use a shear rate of 0.01 m/s for FDEM to carry out direct shear simulations.To balance the relationship between the number of elements and the simulation results in the direct shear simulations,the recommended element size is 1 mm. 展开更多
关键词 ANISOTROPY Empirical expression of cohesion foliation angles Combined finite-discrete element method(FDEM) Shear rate Element size
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Foliations associated to harmonic maps on some complex two ball quotients 被引量:1
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作者 YEUNG Sai-Kee 《Science China Mathematics》 SCIE CSCD 2017年第6期1137-1148,共12页
This article is an attempt to understand harmonic and holomorphic maps between two bounded symmetric domains in special situations. We study foliations associated to a lattice-equivariant harmonic map of small rank fr... This article is an attempt to understand harmonic and holomorphic maps between two bounded symmetric domains in special situations. We study foliations associated to a lattice-equivariant harmonic map of small rank from a complex ball to another. The result is related to rigidity of some complex two ball quotients.Some open questions are raised as well. 展开更多
关键词 harmonic maps foliations RIGIDITY
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A Pinching Theorem for Riemannian Foliations with Parallel Mean Curvature in a Local-Symmetric Riemannian Manifold
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作者 PENG Hui Chun LI Zhi Bo 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2008年第2期383-388,共6页
We discuss the Riemannian foliations with parallel mean curvature in a local- symmetric Riemannian manifold,and obtain a pinching theorem about it.
关键词 Riemannian foliations local-symmetric Riemannian manifold mean curvature DIVERGENCE
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Invariant algebraic curves and rational first integrals of holomorphic foliations in CP(2) 被引量:1
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作者 张祥 《Science China Mathematics》 SCIE 2003年第2期271-279,共9页
In this paper, using the tools of algebraic geometry we provide sufficient conditions for a holomor-phic foliation in CP(2) to have a rational first integral. Moreover, we obtain an upper bound of the degreesof invari... In this paper, using the tools of algebraic geometry we provide sufficient conditions for a holomor-phic foliation in CP(2) to have a rational first integral. Moreover, we obtain an upper bound of the degreesof invariant algebraic curves of a holomorphic foliation in CP(2). Then we use these results to prove that anyholomorphic foliation of degree 2 does not have cubic limit cycles. 展开更多
关键词 HOLOMORPHIC foliation INVARIANT ALGEBRAIC curve RATIONAL first integral CUBIC limit cycle.
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Invariant foliations for parabolic equations 被引量:1
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作者 张伟年 《Science China Mathematics》 SCIE 2000年第4期357-370,共14页
It is proved for parabolic equations that under certain conditions the weak (un-) stable manifolds possess invariant foliations, called strongly (un-) stable foliations. The relevant results on center manifoids are ge... It is proved for parabolic equations that under certain conditions the weak (un-) stable manifolds possess invariant foliations, called strongly (un-) stable foliations. The relevant results on center manifoids are generalized to weak hyperbolic manifolds 展开更多
关键词 PARABOLIC equation INVARIANT FOLIATION weak HYPERBOLIC manifold generalized exponential dichoto-my.
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Foliations on the tangent bundle of Finsler manifolds 被引量:1
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作者 PEYGHAN Esmaei TAYEBI Akbar ZHONG ChunPing 《Science China Mathematics》 SCIE 2012年第3期647-662,共16页
Let M be a smooth manifold with Finsler metric F,and let T M be the slit tangent bundle of M with a generalized Riemannian metric G,which is induced by F.In this paper,we prove that (i) (M,F) is a Landsberg manifold i... Let M be a smooth manifold with Finsler metric F,and let T M be the slit tangent bundle of M with a generalized Riemannian metric G,which is induced by F.In this paper,we prove that (i) (M,F) is a Landsberg manifold if and only if the vertical foliation F V is totally geodesic in (T M,G);(ii) letting a:= a(τ) be a positive function of τ=F 2 and k,c be two positive numbers such that c=2 k(1+a),then (M,F) is of constant curvature k if and only if the restriction of G on the c-indicatrix bundle IM (c) is bundle-like for the horizontal Liouville foliation on IM (c),if and only if the horizontal Liouville vector field is a Killing vector field on (IM (c),G),if and only if the curvature-angular form Λ of (M,F) satisfies Λ=1-a 2/R on IM (c). 展开更多
关键词 Finsler manifold g-natural metrics Riemannian foliation
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The topology of foliations formed by the generic K-orbits of a subclass of the indecomposable MD_5-groups
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作者 VU Le Anh HOA Duong Quang 《Science China Mathematics》 SCIE 2009年第2期351-360,共10页
The paper is a continuation of the authors' works in 2007. We consider the MD_5-foliations associated to connected and simply connected MD_5-groups such that their Lie algebras have 4-dimensional commutative deriv... The paper is a continuation of the authors' works in 2007. We consider the MD_5-foliations associated to connected and simply connected MD_5-groups such that their Lie algebras have 4-dimensional commutative derived ideals. In this study, we give a topological classification of all considered MD_5-foliations. A description of these foliations by certain fibrations or suitable actions of R2 and the Connes' C*-algebras of the foliations which come from fibrations are also given. 展开更多
关键词 Lie group Lie algebra MD_5-group MD_5-algebra K-orbits FOLIATION measured foliation
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FOLIATIONS ON CR MANIFOLD
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作者 韩祖宏 《Science China Mathematics》 SCIE 1992年第6期701-708,共8页
In this paper, we prove that there exist CR foliation and complex foliation on abstractCR manifolds and obtain some properties of these foliations.
关键词 CR MANIFOLD Levi FORMS INTEGRABILITY foliation.
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Smoothness of invariant manifolds and foliations for in nite dimensional random dynamical systems--Dedicated to Professor Shantao Liao
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作者 Jun Shen Kening Lu Weinian Zhang 《Science China Mathematics》 SCIE CSCD 2020年第9期1877-1912,共36页
In this paper,we investigate the smoothness of invariant manifolds and foliations for random dynamical systems with nonuniform pseudo-hyperbolicity in Hilbert spaces.We discuss on the effect of temperedness and the sp... In this paper,we investigate the smoothness of invariant manifolds and foliations for random dynamical systems with nonuniform pseudo-hyperbolicity in Hilbert spaces.We discuss on the effect of temperedness and the spectral gaps in the nonuniform pseudo-hyperbolicity so as to prove the existence of invariant manifolds and invariant foliations,which preserve the CN,τ;(ω)Holder smoothness of the random system in the space variable and the measurability of the random system in the sample point.Moreover,we also prove that the stable foliation is CN-1;(ω)in the base point. 展开更多
关键词 random dynamical system invariant manifold invariant foliation pseudo-hyperbolicity MEASURABILITY
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A class of metrics and foliations on tangent bundle of Finsler manifolds
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作者 Hongchuan XIA Chunping ZHONG 《Frontiers of Mathematics in China》 SCIE CSCD 2017年第2期417-439,共23页
Let (M, F) be a Finsler manifold, and let TMo be the slit tangent bundle of M with a generalized Riemannian metric G, which is induced by F. In this paper, we extract many natural foliations of (TMo, G) and study ... Let (M, F) be a Finsler manifold, and let TMo be the slit tangent bundle of M with a generalized Riemannian metric G, which is induced by F. In this paper, we extract many natural foliations of (TMo, G) and study their geometric properties. Next, we use this approach to obtain new characterizations of Finsler manifolds with positive constant flag curvature. We also investigate the relations between Levi-Civita connection, Cartan connection, Vaisman connection, vertical foliation, and Reinhart spaces. 展开更多
关键词 Finsler manifold FOLIATION constant flag curvature Vaismanconnection
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Laplacians and Spectrum for Singular Foliations
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作者 Iakovos ANDROULIDAKIS 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2014年第5期679-690,共12页
The author surveys Connes' results on the longitudinal Laplace operator along a(regular) foliation and its spectrum, and discusses their generalization to any singular foliation on a compact manifold. Namely, it i... The author surveys Connes' results on the longitudinal Laplace operator along a(regular) foliation and its spectrum, and discusses their generalization to any singular foliation on a compact manifold. Namely, it is proved that the Laplacian of a singular foliation is an essentially self-adjoint operator(unbounded) and has the same spectrum in every(faithful) representation, in particular, in L2 of the manifold and L2 of a leaf.The author also discusses briefly the relation of the Baum-Connes assembly map with the calculation of the spectrum. 展开更多
关键词 LAPLACIAN Singular foliation HOLONOMY
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Contrast of Perspectives of Coherency
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作者 Tian Ma Erik Bollt 《Journal of Applied Mathematics and Physics》 2015年第7期781-791,共11页
Mixing and coherence are fundamental issues at the heart of understanding fluid dynamics and other non-autonomous dynamical systems. Recently the notion of coherence has come to a more rigorous footing, in particular,... Mixing and coherence are fundamental issues at the heart of understanding fluid dynamics and other non-autonomous dynamical systems. Recently the notion of coherence has come to a more rigorous footing, in particular, within the studies of finite-time nonautonomous dynamical systems. Here we recall “shape coherent sets” which is proven to correspond to slowly evolving curvature, for which tangency of finite time stable foliations (related to a “forward time” perspective) and finite time unstable foliations (related to a “backwards time” perspective) serve a central role. We compare and contrast this perspective to both the variational method of geodesics [17], as well as the coherent pairs perspective [12] from transfer operators. 展开更多
关键词 Shape COHERENT Set COHERENT Pairs GEODESIC TRANSPORT Barrier Finite-Time Stable and Unstable foliations Implicit Function Theorem CONTINUATION Mixing TRANSPORT
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Directions of Valley Axes in Relationship to Geological Structure-Element Orientation in the Stribrne Hory Area in the Bohemian-Moravian Uplands (Czech Republic)
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作者 Jan Jurcek Rostislav Melichar 《Journal of Geodesy and Geomatics Engineering》 2015年第2期82-86,共5页
The purpose of this paper is to evaluate control of orientation of foliations and joints on the direction of valley axes in the Stribrne Hory area in the Bohemian-Moravian Highlands in central part of the Czech Republ... The purpose of this paper is to evaluate control of orientation of foliations and joints on the direction of valley axes in the Stribrne Hory area in the Bohemian-Moravian Highlands in central part of the Czech Republic. This area is predominantly built by metamorphic rocks. It is situated near the Pribyslav deep-seated fault. The data concerning of foliations, joints and valley axes were statistically analyzed and then visually compared according to their distribution using direction roses. Directions of valley axes have generally orientation of NNE-SSW, SE, E-W, NW and WNW and coincide with the system of foliations and ordinarily steep joints. 展开更多
关键词 Bohemian-Moravian Uplands TECTONICS foliations joints valleys.
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Extended Group Foliation Method and Functional Separation of Variables to Nonlinear Wave Equations 被引量:9
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作者 QU Chang-Zheng ZHANG Shun-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4X期577-582,共6页
Generalized functional separation of variables to nonlinear evolution equations is studied in terms of the extended group foliation method, which is based on the Lie point symmetry method. The approach is applied to n... Generalized functional separation of variables to nonlinear evolution equations is studied in terms of the extended group foliation method, which is based on the Lie point symmetry method. The approach is applied to nonlinear wave equations with variable speed and external force. A complete classification for the wave equation which admits functional separable solutions is presented. Some known results can be recovered by this approach. 展开更多
关键词 symmetry group group foliation method nonlinear wave equation functional separation of variables
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Chemical U-Th-Pb Monazite Dating of Deformations versus Pluton Emplacement and the Proterozoic History of the Arkansas River Region,Colorado,USA 被引量:6
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作者 CAO Hui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第5期917-926,共10页
Five lengthy periods involving multiple phases of cordierite and andalusite growth were revealed by detailed studies of foliation inflection/intersection axes (FIA) preserved in porphyroblasts in schists from the Ar... Five lengthy periods involving multiple phases of cordierite and andalusite growth were revealed by detailed studies of foliation inflection/intersection axes (FIA) preserved in porphyroblasts in schists from the Arkansas River region in Colorado, USA. The regionally consistent character of the succession of five different FIA trends enabled the relative timing of each FIA with respect to the next to be determined. The FIA succession from first to last is: FIA 1 trending W-E, FIA 2 trending SSW- NNE, FIA 3 trending NNW-SSE, FIA 4 trending NW-SE and FIA 5 trending SW-NE. For four of the FIA sets, samples were found containing monazite grains preserved as inclusions. These were dated on an electron microprobe. The ages obtained concur exactly with the FIA succession, with FIA 1 at 1506±15 Ma, FIA 2 at 1467±23 Ma, FIA 3 at 1425±18 Ma, FIA 4 not dated and FIA 5 at 1366±20 Ma. These ages are directly reflected in a succession of plutons in the surrounding region dated by other isotopic approaches, suggesting that deformation, metamorphism and pluton emplacement occurred together episodically, but effectively continuously, for some 140 Ma. 展开更多
关键词 monazite dating Arkansas River region foliation inflection/intersection axes
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Functional Separable Solutions to Nonlinear Diffusion Equations by Group Foliation Method 被引量:5
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作者 HU Jia-Yi QU Chang-Zheng YIN Hui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期193-199,共7页
We consider the functional separation of variables to the nonlinear diffusion equation with source and convection term: ut = (A(x)D(u)ux)x + B(x)Q(u), Ax ≠ 0. The functional separation of variables to thi... We consider the functional separation of variables to the nonlinear diffusion equation with source and convection term: ut = (A(x)D(u)ux)x + B(x)Q(u), Ax ≠ 0. The functional separation of variables to this equation is studied by using the group foliation method. A classification is carried out for the equations which admit the function separable solutions. As a consequence, some solutions to the resulting equations are obtained. 展开更多
关键词 group foliation method functional separation of variable nonlinear diffusion equation symmetry group
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Resolving the Routine Presence of Kyanite, Andalusite and Sillimanite across a Region using Foliation Intersection/Inflection Axes Preserved in Porphyroblasts, Petrographic Observations and Thermobarometry 被引量:3
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作者 Asghar ALI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第5期1241-1250,共10页
Constraints from P-T pseudosections (MnNCKFMASH system), foliation intersection/ inflection axes preserved in porphyroblasts (FIAs), mineral assemblages and textural relationships for rocks containing all three Al... Constraints from P-T pseudosections (MnNCKFMASH system), foliation intersection/ inflection axes preserved in porphyroblasts (FIAs), mineral assemblages and textural relationships for rocks containing all three Al2 SiO5 polymorphs indicate a kyanite→ andalusite→ sillimanite sequential formation at different times rather than stable coexistence at the Al2SiO5 triple point. All three Al2SiO5 polymorphs grew in the Chl, Bt, Ms, Grt, St, Pl and Crd bearing Ordovician Clayhole Schist in Balcooma, northeastern Australia separately along a looped P-T-t-D path that swaps from clockwise to anticlockwise in the tectono-metamorphic history of the region. Kyanite grew during crustal thickening in an Early Silurian Orogenic event followed by decompression/heating, andalusite and fibrolitic sillimanite growth during Early Devonian exhumation. 展开更多
关键词 Al2SiO5 triple point microtextures foliation intersection/inflection axes Barrovian sequence episodic porphyroblast growth
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