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The Coxeter Trisection and the Hadwiger Conjecture in Multidimensional Spaces
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作者 István Lénárt 《Journal of Applied Mathematics and Physics》 2024年第12期4301-4321,共21页
In this article, I consider the right triangle as the simplex in the Euclidean plane, and extend this definition to higher dimensions. The n-dimensional simplex has one hypotenuse and (n−1)legs (catheti). The (n−1)leg... In this article, I consider the right triangle as the simplex in the Euclidean plane, and extend this definition to higher dimensions. The n-dimensional simplex has one hypotenuse and (n−1)legs (catheti). The (n−1)legs define an orthogonal path of edges in the solid with perpendicular adjacent edges along the path. The length of the hypotenuse and the volume of the solid can be calculated without the Cayley-Menger determinant, by direct extension of the corresponding right triangle formulas. I give a proof of the existence of these shapes, describe the distribution of right angles in them, give an algebraic proof of the Coxeter trisection of a right tetrahedron into three smaller right tetrahedra, and generalize this construction to n-dimensional spaces. Finally, I investigate the connection between the Coxeter partition and the Hadwiger conjecture on the partition of the simplex into orthoschemes, which I call Pythagorean simplexes. 展开更多
关键词 Generalized Pythagoras Theorem Description of a Pythagorean simplex Pythagorean Unit simplex Coxeter Partition of a simplex in -dimensional Space Relation to the Hadwiger Conjecture
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Preliminary Exploration on Properties of the Equidistant Conjugate Points of Higher Dimensional Simplex
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作者 ZENG Jian-guo 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第1期77-81,共5页
In this paper, the concept of the equidistant conjugate points of a triangle to the n-dimensional Euclidean space is extended. The concept of equidistant conjugate point in high dimensional simplex is defined, and the... In this paper, the concept of the equidistant conjugate points of a triangle to the n-dimensional Euclidean space is extended. The concept of equidistant conjugate point in high dimensional simplex is defined, and the property of the equidistant conjugate points of a triangle is generalized to high dimensional simplex. 展开更多
关键词 simplex equidistant conjugate point n-dimensional Euclidean space kdimensional spatial (k+1)-polygon
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Lipschitz Estimates for Commutators of N-dimensional Fractional Hardy Operators 被引量:8
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作者 ZHENG QING-YU Fu ZUN-WEI 《Communications in Mathematical Research》 CSCD 2009年第3期241-245,共5页
In this paper, it is proved that the commutator Hβ,b which is generated by the n-dimensional fractional Hardy operator Hβ and b ∈λα (R^n) is bounded from L^p(R^n) to L^q(R^n), where 0 〈 α 〈 1, 1 〈 p, q ... In this paper, it is proved that the commutator Hβ,b which is generated by the n-dimensional fractional Hardy operator Hβ and b ∈λα (R^n) is bounded from L^p(R^n) to L^q(R^n), where 0 〈 α 〈 1, 1 〈 p, q 〈 ∞ and 1/P - 1/q = (α+β)/n. Furthermore, the boundedness of Hβ,b on the homogenous Herz space Kq^α,p(R^n) is obtained. 展开更多
关键词 COMMUTATOR n-dimensional fractional Hardy operator Lipschitz function Herz space
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A new approach to fuzzy dynamic fault tree analysis using the weakest n-dimensional t-norm arithmetic 被引量:4
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作者 Ge JIANG Hongjie YUAN +1 位作者 Peichang LI Peng LI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2018年第7期1506-1514,共9页
Dynamic fault tree analysis is widely used for the reliability analysis of the complex system with dynamic failure characteristics. In many circumstances, the exact value of system reliability is difficult to obtain d... Dynamic fault tree analysis is widely used for the reliability analysis of the complex system with dynamic failure characteristics. In many circumstances, the exact value of system reliability is difficult to obtain due to absent or insufficient data for failure probabilities or failure rates of components. The traditional fuzzy operation arithmetic based on extension principle or interval theory may lead to fuzzy accumulations. Moreover, the existing fuzzy dynamic fault tree analysis methods are restricted to the case that all system components follow exponential time-to-failure distributions. To overcome these problems, a new fuzzy dynamic fault tree analysis approach based on the weakest n-dimensional t-norm arithmetic and developed sequential binary decision diagrams method is proposed to evaluate system fuzzy reliability. Compared with the existing approach,the proposed method can effectively reduce fuzzy cumulative and be applicable to any time-tofailure distribution type for system components. Finally, a case study is presented to illustrate the application and advantages of the proposed approach. 展开更多
关键词 Fuzzy dynamic fault treeanalysis Fuzzy theory Reliability evaluation Sequential binary decision diagrams The weakest n-dimensional t-norm arithmetic
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On Multiplicative Generators of n-Dimensional Overlap Functions 被引量:1
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作者 Hai Xie 《Applied Mathematics》 2020年第11期1061-1069,共9页
In this paper, inspired by the multiplicative generators of overlap functions, we mainly propose the concepts of multiplicative generator pairs of n-dimensional overlap functions, in order to extend the dimensionality... In this paper, inspired by the multiplicative generators of overlap functions, we mainly propose the concepts of multiplicative generator pairs of n-dimensional overlap functions, in order to extend the dimensionality of overlap functions from 2 to n. We present the condition under which the pair (g, h) can multiplicatively generate an n-dimensional overlap function O<sub>g,h</sub>. we focus on the homogeneity and idempotency property on multiplicatively generated n-dimensional overlap functions. 展开更多
关键词 n-dimensional Overlap Functions Overlap Functions Multiplicative Generators
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General calculation formulas and recurrence relations of radial matrix elements for relativistic n-dimensional hydrogen atom of spin S=0 被引量:1
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作者 CHENChang-yuan LUFa-lin SUNDong-sheng 《原子与分子物理学报》 CAS CSCD 北大核心 2004年第3期432-440,共9页
In this paper, the general calculation formulas of radial matrix elements for relativistic n-dimensional hydrogen atom of spin S=0 are obtained, and the recurrence relation of different power order radial matrix eleme... In this paper, the general calculation formulas of radial matrix elements for relativistic n-dimensional hydrogen atom of spin S=0 are obtained, and the recurrence relation of different power order radial matrix elements are also derived. 展开更多
关键词 n-dimensional hydrogen atom-type potential Klein-Cordon equation Radial matrix dements GEnERAL calculation FORMULAS RECURREnCE relations
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STUDY ON LIQUID CRYSTAL POLYMERS WITH TWO-DIMENSIONAL MESOGENIC UNITS 被引量:1
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作者 张春晓 李自法 +1 位作者 周其凤 周洪兵 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1993年第4期58-63,共6页
A series of liquid crystalline polymers with two-dimensional mesogenic units were synthesized by solution polycondensation at low temperature. All the polymers were liquid crystalline. The melting temperature T;(exce... A series of liquid crystalline polymers with two-dimensional mesogenic units were synthesized by solution polycondensation at low temperature. All the polymers were liquid crystalline. The melting temperature T;(except that with substituent of methoxy) and the clearing temperature T;of the polymers change regularly with varying of the length of the alkyl substituent groups. 展开更多
关键词 Liquid crystal polymer Two-dimensional mesogenic unit n-2 ' 5 '-dihydroxy benzylidene-4-alkoxyaniline Monotropic nematics
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Spherically symmetric solution in higher-dimensional teleparallel equivalent of general relativity
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作者 Gamal G.L.Nashed 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第2期120-127,共8页
A theory of(N+1)-dimensional gravity is developed on the basis of the teleparallel equivalent of general relativity(TEGR).The fundamental gravitational field variables are the(N+1)-dimensional vector fields,de... A theory of(N+1)-dimensional gravity is developed on the basis of the teleparallel equivalent of general relativity(TEGR).The fundamental gravitational field variables are the(N+1)-dimensional vector fields,defined globally on a manifold M,and the gravitational field is attributed to the torsion.The form of Lagrangian density is quadratic in torsion tensor.We then give an exact five-dimensional spherically symmetric solution(Schwarzschild(4+1)-dimensions).Finally,we calculate energy and spatial momentum using gravitational energy-momentum tensor and superpotential 2-form. 展开更多
关键词 n+1)-dimensional teleparallel equivalent of general relativity five-dimensional solution energy and momentum
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High Dimensional Cluster Analysis Using Path Lengths
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作者 Kevin Mcilhany Stephen Wiggins 《Journal of Data Analysis and Information Processing》 2018年第3期93-125,共33页
A hierarchical scheme for clustering data is presented which applies to spaces with a high number of dimensions (). The data set is first reduced to a smaller set of partitions (multi-dimensional bins). Multiple clust... A hierarchical scheme for clustering data is presented which applies to spaces with a high number of dimensions (). The data set is first reduced to a smaller set of partitions (multi-dimensional bins). Multiple clustering techniques are used, including spectral clustering;however, new techniques are also introduced based on the path length between partitions that are connected to one another. A Line-of-Sight algorithm is also developed for clustering. A test bank of 12 data sets with varying properties is used to expose the strengths and weaknesses of each technique. Finally, a robust clustering technique is discussed based on reaching a consensus among the multiple approaches, overcoming the weaknesses found individually. 展开更多
关键词 CLUSTERInG PATH LEnGTH COnSEnSUS n-dimensional Line of SIGHT
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Synthesis,Crystal Structure and Magnetic Property of a New One-dimensional Complex [Mn(μ_(1,5)-dca)_2(POM)_2] (POM = 3-Methyl-4-nitropyridine-N-oxide,dca = Dicyanamide)
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作者 魏荣敏 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第12期1589-1592,共4页
The title complex [Mn(μ1,5-dca)2(POM)2] (C16H12MnN10O6,Mr = 495.30) has been prepared and structurally characterized. It crystallizes in triclinic,space group P1 with a = 7.4685(9),b = 7.5406(9),c = 9.8646... The title complex [Mn(μ1,5-dca)2(POM)2] (C16H12MnN10O6,Mr = 495.30) has been prepared and structurally characterized. It crystallizes in triclinic,space group P1 with a = 7.4685(9),b = 7.5406(9),c = 9.8646(12)A,α = 83.202(2),β = 69.1200(10),γ = 79.4130(10)o,V = 509.38(11) A^3,Z = 1,Dc = 1.602 g/cm^3,F(000) = 249,μ(MoKa) = 0.704 mm^-1,the final R = 0.0701 and wR = 0.2071 for 1615 observed reflections with I 〉 2σ(I). Each Mn(Ⅱ) exhibits a slightly distorted octahedral environment and connects with each other to form a one-dimensional complex by double bridging μ1,5-N≡C-N-C≡N ligands. The magnetic susceptibility of the title complex has been measured,and it displays weak antiferromagnetic interactions. 展开更多
关键词 3-methyl-4-nitropyridine-n-oxide DICYAnAMIDE one-dimensional antiferromagnetic
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具有(2m+1)次非线性项和时空变系数的广义(n+1)维薛定谔方程的相似变换和精确解
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作者 王岗伟 谭子轩 《物理学报》 北大核心 2025年第11期134-140,共7页
薛定谔型方程是一类十分重要的微分方程.高维及变系数薛定谔型方程的研究具有一定的价值和意义.本文利用相似变换推导了(n+1)维(2m+1)次变系数非线性薛定谔方程的一类新的孤子解,给出了系数之间满足的关系.并利用定态薛定谔方程的解,得... 薛定谔型方程是一类十分重要的微分方程.高维及变系数薛定谔型方程的研究具有一定的价值和意义.本文利用相似变换推导了(n+1)维(2m+1)次变系数非线性薛定谔方程的一类新的孤子解,给出了系数之间满足的关系.并利用定态薛定谔方程的解,得到了(n+1)维(2m+1)次变系数非线性薛定谔方程的明暗孤子解.最后,对于特殊的情况,给出了明暗孤立子解的图像,并系统分析了孤子解的空间结构和传播特性. 展开更多
关键词 (n+1)维(2m+1)次非线性薛定谔方程 相似变换 精确解
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Explicit expressions and recurrence formulas of radial average value for N-dimensional hydrogen atom
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作者 CHEN Chang-yuan, SUN Dong-sheng, LIU You-we, LIU Cheng-lin(Department of Physics, Yancheng Teachers College, Yancheng 224002, China) 《原子与分子物理学报》 CAS CSCD 北大核心 2002年第2期201-204,共4页
In this paper, two recurrence formulas for radial average values of N-dimensional hydrogen atom are derived. Explicit expressions for <n rJ N-2 |r s|n rJ N-2 > are given for 3≥s≥-6. These results can be applie... In this paper, two recurrence formulas for radial average values of N-dimensional hydrogen atom are derived. Explicit expressions for <n rJ N-2 |r s|n rJ N-2 > are given for 3≥s≥-6. These results can be applied to discuss average value of centrifugal potential energy and other physical quantities. The relevant results of the usual hydrogen atom are contained in more general conclusion of this paper as special cases. 展开更多
关键词 量子力学 循环准则 氢原子 电离
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Gear-like array of (H_2O)_(12) as building blocks in one-dimensional supramolecular assembly
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作者 Chun Hua Ge Xiang Dong Zhang Yong Chao Ma Lei Guan Chun Yue Shi Xiao Yan Zhang Ya Nan Guo Qi Tao Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第11期1389-1391,共3页
The preparation and crystal structure of complex Co(Hsae)2·2H2O (1, H2sae = N-salicylidene-2-iminoethanol) are reported. X- ray analysis revealed that every six Co(Hsae)2 forms a cyclic chip and every 12 wa... The preparation and crystal structure of complex Co(Hsae)2·2H2O (1, H2sae = N-salicylidene-2-iminoethanol) are reported. X- ray analysis revealed that every six Co(Hsae)2 forms a cyclic chip and every 12 water forms a novel gear-like cluster. Acting as building blocks, the gear-like water cluster and complex chip are connected in A-B fashion and extend into one-dimensional supramolecular chain. Hydrogen bond is the primary bridging force in the formation of supramolecular framework. 展开更多
关键词 Co(Ⅱ) complex n-Salicylidene-2-iminoethanol Hydrogen bond Water cluster One-dimensional chain Supramolecular chemistry
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The Realization of 4-dimensional 3-Lie Algebras
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作者 刘建波 张艳艳 张知学 《Northeastern Mathematical Journal》 CSCD 2007年第3期247-254,共8页
In this paper, we mainly investigate the realization of 3-Lie algebras from a family of Lie algebras. We prove the realization theorem, offer a concrete example realizing all type of 4-dimensional 3-Lie algebras, and ... In this paper, we mainly investigate the realization of 3-Lie algebras from a family of Lie algebras. We prove the realization theorem, offer a concrete example realizing all type of 4-dimensional 3-Lie algebras, and also give some properties about semi-simple n-Lie algebras. 展开更多
关键词 4-dimensional 3-Lie algebra REALIZATIOn semi-simple n-Lie algebra
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Wronskian and Grammian Solutions for Generalized (n + 1)-Dimensional KP Equation with Variable Coefficients
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作者 Hongwei Fu Yang Song Juan Xu 《Applied Mathematics》 2012年第2期154-157,共4页
The generalized (n + 1)-dimensional KP equation with variable coefficients is investigated in this paper. The bilinear form of the equation has been obtained by the Hirota direct method. In addition, with the help of ... The generalized (n + 1)-dimensional KP equation with variable coefficients is investigated in this paper. The bilinear form of the equation has been obtained by the Hirota direct method. In addition, with the help of Wronskian technique and the Pfaffian properties, Wronskian and Grammian solutions have been generated. 展开更多
关键词 Generalized Variable Coefficient (n + 1)-dimensional KP Equation HIROTA Bilinear Method WROnSKIAn SOLUTIOn Grammian SOLUTIOn
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SYNTHESIS AND CHARACTERIZATION OF LIQUID CRYSTAL POLYMERS WITH T-SHAPED TWO-DIMENSIONAL MESOGENIC UNITS
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作者 李自法 陈志军 +2 位作者 张淑媛 曹少魁 周其凤 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1996年第1期71-79,共9页
Two series of new liquid crystalline polymers with T-shaped two-dimensional mesogenic units were synthesized by low temperature solution polycondensations of 4-substituted N-2, 5-dihydroxybenzylidene aniline monomers ... Two series of new liquid crystalline polymers with T-shaped two-dimensional mesogenic units were synthesized by low temperature solution polycondensations of 4-substituted N-2, 5-dihydroxybenzylidene aniline monomers with different diacyl dichlorides. The polymers were found to be nematic and shown liquid crystalline behavior. The melting temperature T-m and the clearing temperature T-i of the polymers change regularly with varying of the monomer structures. 展开更多
关键词 liquid crystal polymer T-shaped two-dimensional mesogenic unit n-2 5-dihydroxybenzylidene-4-substituted aniline
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Constructions of <i>n</i>-Dimensional Overlap Functions Based on Bivariate Overlap Functions
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作者 Hai Xie 《Journal of Applied Mathematics and Physics》 2021年第11期2757-2764,共8页
In this paper, we firstly introduce some new results on overlap functions and <em>n</em>-dimensional overlap functions. On the other hand, in a previous study, Gómez <em>et al</em>. presen... In this paper, we firstly introduce some new results on overlap functions and <em>n</em>-dimensional overlap functions. On the other hand, in a previous study, Gómez <em>et al</em>. presented some open problems. One of these open problems is “to search the construction of <em>n</em>-dimensional overlapping functions based on bi-dimensional overlapping functions”. To answer this open problem, in this paper, we mainly introduce one construction method of <em>n</em>-dimensional overlap functions based on bivariate overlap functions. We mainly use the conjunction operator ∧ to construct <em>n</em>-dimensional overlap functions <img src="Edit_0e82dd84-0f25-4b14-8f26-ae9532b10190.bmp" alt="" /> based on bivariate overlap functions and study their basic properties. 展开更多
关键词 Overlap Functions n-dimensional Overlap Functions Conjunction Operator
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Random Subspace Learning Approach to High-Dimensional Outliers Detection
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作者 Bohan Liu Ernest Fokoué 《Open Journal of Statistics》 2015年第6期618-630,共13页
We introduce and develop a novel approach to outlier detection based on adaptation of random subspace learning. Our proposed method handles both high-dimension low-sample size and traditional low-dimensional high-samp... We introduce and develop a novel approach to outlier detection based on adaptation of random subspace learning. Our proposed method handles both high-dimension low-sample size and traditional low-dimensional high-sample size datasets. Essentially, we avoid the computational bottleneck of techniques like Minimum Covariance Determinant (MCD) by computing the needed determinants and associated measures in much lower dimensional subspaces. Both theoretical and computational development of our approach reveal that it is computationally more efficient than the regularized methods in high-dimensional low-sample size, and often competes favorably with existing methods as far as the percentage of correct outlier detection are concerned. 展开更多
关键词 HIGH-dimensional Robust OUTLIER DETECTIOn Contamination Large p Small n Random Subspace Method Minimum COVARIAnCE DETERMInAnT
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基于智慧教学的高校专业课“2+3+N”教学模式探索
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作者 黎秀 谭俊锋 段华琼 《计算机教育》 2025年第10期245-250,共6页
针对智慧教育背景下高校专业课教学的机遇与挑战,提出“2+3+N”教学模式并阐述其优势,以数据结构与算法课程为例,从多平台协同、多元教学方法融合及多维度评价体系方面介绍该模式的教学应用,最后说明应用成效。
关键词 智慧教学 “2+3+n”教学模式 多元教学 多维度评价
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The Additive Generators of <i>n</i>-Dimensional Overlap Functions
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作者 Hai Xie 《Journal of Applied Mathematics and Physics》 2021年第8期2159-2169,共11页
In this paper, we introduce the concepts of additive generators and additive generator pair of <em>n</em>-dimensional overlap functions, in order to extend the dimensionality of overlap functions from 2 to... In this paper, we introduce the concepts of additive generators and additive generator pair of <em>n</em>-dimensional overlap functions, in order to extend the dimensionality of overlap functions from 2 to <em>n</em>. We mainly discuss the conditions under which an <em>n</em>-dimensional overlap function can be expressed in terms of its generator pair. 展开更多
关键词 Overlap Functions n-dimensional Overlap Functions Additive Generators Additive Generator Pair
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