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Glymphatic function and its influencing factors in different glucose metabolism states 被引量:4
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作者 Bin Tian Chen Zhao +7 位作者 Jia-Li Liang Hui-Ting Zhang Yi-Fan Xu Hui-Lei Zheng Jia Zhou Jiang-Nian Gong Shu-Ting Lu Zi-San Zeng 《World Journal of Diabetes》 SCIE 2024年第7期1537-1550,共14页
BACKGROUND Dysfunction of the glymphatic system in the brain in different stages of altered glucose metabolism and its influencing factors are not well characterized.AIM To investigate the function of the glymphatic s... BACKGROUND Dysfunction of the glymphatic system in the brain in different stages of altered glucose metabolism and its influencing factors are not well characterized.AIM To investigate the function of the glymphatic system and its clinical correlates in patients with different glucose metabolism states,the present study employed diffusion tensor imaging along the perivascular space(DTI-ALPS)index.METHODS Sample size was calculated using the pwr package in R software.This crosssectional study enrolled 22 patients with normal glucose metabolism(NGM),20 patients with prediabetes,and 22 patients with type 2 diabetes mellitus(T2DM).A 3.0T magnetic resonance imaging was used to evaluate the function of the glymphatic system.The mini-mental state examination(MMSE)was used to assess general cognitive function.The DTI-ALPS index of bilateral basal ganglia and the mean DTI-ALPS index was calculated.Further,the correlation between DTI-ALPS and clinical features was assessed.RESULTS The left-side,right-side,and mean DTI-ALPS index in the T2DM group were significantly lower than that in the NGM group.The right-side DTI-ALPS and mean DTI-ALPS index in the T2DM group were significantly lower than those in the prediabetes group.DTI-ALPS index lateralization was not observed.The MMSE score in the T2DM group was significantly lower than that in the NGM and prediabetes group.After controlling for sex,the left-side DTI-ALPS and mean DTI-ALPS index in the prediabetes group were positively correlated with 2-hour postprandial blood glucose level;the left-side DTI-ALPS index was negatively correlated with total cholesterol and low-density lipoprotein level.The right-side DTI-ALPS and mean DTI-ALPS index were negatively correlated with the glycosylated hemoglobin level and waist-to-hip ratio in the prediabetes group.The left-side,right-side,and mean DTI-ALPS index in the T2DM group were positively correlated with height.The left-side and mean DTIALPS index in the T2DM group were negatively correlated with high-density lipoprotein levels. 展开更多
关键词 Glymphatic system PREDIABETES Type 2 diabetes mellitus Magnetic resonance imaging Diffusion tensor imaging along the perivascular space
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A Comprehensive Survey on STP Approach to Finite Games 被引量:7
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作者 CHENG Daizhan WU Yuhu +1 位作者 ZHAO Guodong FU Shihua 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2021年第5期1666-1680,共15页
Nowadays the semi-tensor product(STP)approach to finite games has become a promising new direction.This paper provides a comprehensive survey on this prosperous field.After a brief introduction for STP and finite(netw... Nowadays the semi-tensor product(STP)approach to finite games has become a promising new direction.This paper provides a comprehensive survey on this prosperous field.After a brief introduction for STP and finite(networked)games,a description for the principle and fundamental technique of STP approach to finite games is presented.Then several problems and recent results about theory and applications of finite games via STP are presented.A brief comment about the potential use of STP to artificial intelligence is also proposed. 展开更多
关键词 Finite game game-theoretic control potential game semi-tensor product vector space structure of finite game
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基于L-STM模型的中文情感分类 被引量:6
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作者 王景中 庞丹丹 《计算机工程与设计》 北大核心 2018年第11期3438-3443,共6页
现有情感分类方法将词作为文本特征,把高阶数据展开为向量形式,同时映射到高维向量空间进行训练,但数据原有高阶结构必然受到影响,甚至造成文本数据特征维数过高,最终引起过拟合现象。面对这种情况,利用张量空间模型令文本数据张量化,基... 现有情感分类方法将词作为文本特征,把高阶数据展开为向量形式,同时映射到高维向量空间进行训练,但数据原有高阶结构必然受到影响,甚至造成文本数据特征维数过高,最终引起过拟合现象。面对这种情况,利用张量空间模型令文本数据张量化,基于STM模型配合LSTM神经网络实现L-STM算法模型,将向量序列作为LSTM网络输入,由此实现更高级优化,可有效降低参数最优解计算期间迭代次数。经实验分析不难发现,基于张量空间的L-STM模型可消除文本数据过拟合问题,加快训练速度,全面保证情感文本分类准确率。 展开更多
关键词 情感分类 词向量 张量空间模型 支持张量机 LSTM神经网络
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Insights into glymphatic system dysfunction and glucose continuum
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作者 Tsvetelina Velikova Georgi Vasilev 《World Journal of Diabetes》 SCIE 2024年第12期2404-2408,共5页
In this article,we comment on an original article published in a recent issue of the World Journal of Diabetes.That observational cross-sectional study focused on investigating the function of the glymphatic system an... In this article,we comment on an original article published in a recent issue of the World Journal of Diabetes.That observational cross-sectional study focused on investigating the function of the glymphatic system and its clinical correlates in patients with different glucose metabolism states by using diffusion tensor imaging along the perivascular space(DTI-ALPS)index.It was shown that the cerebral glymphatic system may be dysfunctional in patients with type 2 diabetes.Various clinical variables affected the DTI-ALPS index in different glucose metabolism states.In conclusion,the study by Tian et al improves the under-standing of the pathophysiology of diabetes-associated brain damage and pro-vides insights for early diagnosis. 展开更多
关键词 Glymphatic system PREDIABETES Type 2 diabetes mellitus Magnetic reso-nance imaging Diffusion tensor imaging along the perivascular space
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基于BP网络的机床主轴故障诊断研究 被引量:4
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作者 李振雨 王好臣 +1 位作者 王功亮 李家鹏 《机械设计与制造》 北大核心 2019年第10期130-133,139,共5页
针对机床主轴在运转过程中由于高速、热变形和应力集中等原因而发生平移、旋转、压缩和伸展等,提出了一种基于BP神经网络和误差标定拟合对机床主轴轴心轨迹误差预测的方法。该方法首先通过实验测量出机床主轴轴心轨迹的偏心数据形成样本... 针对机床主轴在运转过程中由于高速、热变形和应力集中等原因而发生平移、旋转、压缩和伸展等,提出了一种基于BP神经网络和误差标定拟合对机床主轴轴心轨迹误差预测的方法。该方法首先通过实验测量出机床主轴轴心轨迹的偏心数据形成样本,运用BP神经网络对样本进行训练,然后根据样本训练结果预测机床主轴轴心偏转的将来值,最后通过三维张量空间分布函数分析将来值与理论值拟合情况得出机床运转状态。实验结果显示,当迭代次数epoch=2,训练误差为Validation=0.0052442时,训练后的拟合曲线拟合效果较好,此时BP训练状态最佳,训练后的主轴偏转结果能够反映和预测机床运转状态。本方法对于生产过程中的机床定期维修保养具有重要的指导意义。 展开更多
关键词 机床主轴 张量空间 BP神经网络 轴心轨迹
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面向降频污染攻击的智能交通拥堵态势量化分析 被引量:2
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作者 相迎宵 李轶珂 +5 位作者 刘吉强 王潇瑾 陈彤 童恩栋 牛温佳 韩臻 《软件学报》 EI CSCD 北大核心 2023年第2期833-848,共16页
随着网联车辆的快速发展和开放化,智能信号灯规划系统承受着巨大的网络攻击风险.已有相关研究发现,定频数据污染对规划脆弱性的攻击造成了交通拥堵爆增,但缺乏对降频污染攻击的全时序拥堵态势量化与分析,在检测预警与持续对抗方面有一... 随着网联车辆的快速发展和开放化,智能信号灯规划系统承受着巨大的网络攻击风险.已有相关研究发现,定频数据污染对规划脆弱性的攻击造成了交通拥堵爆增,但缺乏对降频污染攻击的全时序拥堵态势量化与分析,在检测预警与持续对抗方面有一定的局限性.将开源智能信号灯规划系统I-SIG及其规划算法COP作为研究对象,提出一种面向多个降频污染攻击的统一拥堵态势量化与分析框架,构造态势发展的时空序列三阶张量空间,并设计极值分析、平稳性分析和关联性分析,实现基于函数依赖关系的一体化分析方法.在交通模拟环境VISSIM平台上,验证了该量化分析的有效性并报告新发现. 展开更多
关键词 污染攻击 拥堵态势 量化分析 智能交通 张量空间
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张量紧说 被引量:1
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作者 唐少强 《力学与实践》 北大核心 2023年第1期150-156,共7页
本文从线性空间出发,介绍了线性泛函与对偶空间,在此基础上以双线性型为例引出了张量的数学定义-多线性泛函;另一方面,内积作为一种特殊的双线性型给予向量另一种身份:余向量,由此通过限定定义张量的线性空间都取为Rn(n=2,3),就得到了(... 本文从线性空间出发,介绍了线性泛函与对偶空间,在此基础上以双线性型为例引出了张量的数学定义-多线性泛函;另一方面,内积作为一种特殊的双线性型给予向量另一种身份:余向量,由此通过限定定义张量的线性空间都取为Rn(n=2,3),就得到了(连续介质)力学中常用的张量,即在基变换下坐标(或称分量)按照给定规则变化的量。进一步给出了张量的张量积、缩并、点积和双点积运算。 展开更多
关键词 张量 客观性原理 线性泛函 对偶空间 内积空间
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Embedding Cross-Dimensional Vector Space into ℓ^(2)
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作者 XUE Shengli ZHANG Lijun +2 位作者 XIE Zhiqi YAN Weijun ZHANG Kuize 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2023年第6期2309-2324,共16页
The cross-dimensional dynamical systems have received increasing research attention in recent years.This paper characterizes the structure features of the cross-dimensional vector space.Specifically,it is proved that ... The cross-dimensional dynamical systems have received increasing research attention in recent years.This paper characterizes the structure features of the cross-dimensional vector space.Specifically,it is proved that the completion of cross-dimensional vector space is an infinite-dimensional separable Hilbert space.Hence,it means that one can isometrically and linearly embed the crossdimensional vector space into theℓ^(2),which is known as the space of square summable sequences.This result will be helpful in the modeling and analyzing the dynamics of cross-dimensional dynamical systems. 展开更多
关键词 Cross-dimensional vector space ℓ^(2)space semi-tensor product separable Hilbert space V-equivalence
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A new semi-tensor product of matrices 被引量:2
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作者 Daizhan CHENG Zequn LIU 《Control Theory and Technology》 EI CSCD 2019年第1期4-12,共9页
A new matrix product, called the second semi-tensor product (STP-Ⅱ) of matrices is proposed. It is similar to the classical semi-tensor product (STP-I). First, its fundamental properties are presented. Then, the equi... A new matrix product, called the second semi-tensor product (STP-Ⅱ) of matrices is proposed. It is similar to the classical semi-tensor product (STP-I). First, its fundamental properties are presented. Then, the equivalence relation caused by STP-II is obtained. Using this equivalence, a quotient space is also obtained. Finally, the vector space structure, the metric and the metric topology, the projection and subspaces, etc. of the quotient space are investigated in detail. 展开更多
关键词 SECOND sime-tensor product (STP-Ⅱ) EQUIVALENCE class QUOTIENT space TOPOLOGY METRIC
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对称张量空间下高阶正则化的图像恢复模型 被引量:2
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作者 刘孝艳 冯象初 《计算机科学》 CSCD 北大核心 2013年第11A期359-362,共4页
为降低ROF模型的阶梯效应和高阶正则化方法对边缘的模糊,在对称张量空间中用二阶对称梯度构造正则项建立了新的图像去噪模型,并通过分析新模型的性质,给出了一种有效的原始-对偶算法。一方面,二阶对称梯度高于一阶导数的特性可以有效地... 为降低ROF模型的阶梯效应和高阶正则化方法对边缘的模糊,在对称张量空间中用二阶对称梯度构造正则项建立了新的图像去噪模型,并通过分析新模型的性质,给出了一种有效的原始-对偶算法。一方面,二阶对称梯度高于一阶导数的特性可以有效地降低阶梯效应;另一方面,二阶对称梯度模低于二阶导数模的特性能有效地保持图像的边缘等细节特征。数值仿真实验表明,新模型达到了理论分析的效果,新算法运算快捷、稳定。 展开更多
关键词 图像恢复 张量空间 二阶对称梯度
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Information space of sensor networks:Lagrangian,energy-momentum tensor,and applications 被引量:1
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作者 Mo TAO Shaoping WANG +3 位作者 Hong CHEN Han PAN Jian SHI Yuwei ZHANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第3期271-284,共14页
It is a challenge to investigate the interrelationship between the geometric structure and performance of sensor networks due to the increasingly complex and diverse architecture of them.This paper presents two new fo... It is a challenge to investigate the interrelationship between the geometric structure and performance of sensor networks due to the increasingly complex and diverse architecture of them.This paper presents two new formulations for the information space of sensor networks,including Lagrangian and energy–momentum tensor,which are expected to integrate sensor networks target tracking and performance evaluation from a unified perspective.The proposed method presents two geometric objects to represent the dynamic state and manifold structure of the information space of sensor networks.Based on that,the authors conduct the property analysis and target tracking of sensor networks.To the best of our knowledge,it is the first time to investigate and analyze the information energy-momentum tensor of sensor networks and evaluate the performance of sensor networks in the context of target tracking.Simulations and examples confirm the competitive performance of the proposed method. 展开更多
关键词 Energy-momentum tensor Information science Information space Sensor networks Target tracking
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Design of semi-tensor product-based kernel function for SVM nonlinear classification 被引量:2
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作者 Shengli Xue Lijun Zhang Zeyu Zhu 《Control Theory and Technology》 EI CSCD 2022年第4期456-464,共9页
The kernel function method in support vector machine(SVM)is an excellent tool for nonlinear classification.How to design a kernel function is difficult for an SVM nonlinear classification problem,even for the polynomi... The kernel function method in support vector machine(SVM)is an excellent tool for nonlinear classification.How to design a kernel function is difficult for an SVM nonlinear classification problem,even for the polynomial kernel function.In this paper,we propose a new kind of polynomial kernel functions,called semi-tensor product kernel(STP-kernel),for an SVM nonlinear classification problem by semi-tensor product of matrix(STP)theory.We have shown the existence of the STP-kernel function and verified that it is just a polynomial kernel.In addition,we have shown the existence of the reproducing kernel Hilbert space(RKHS)associated with the STP-kernel function.Compared to the existing methods,it is much easier to construct the nonlinear feature mapping for an SVM nonlinear classification problem via an STP operator. 展开更多
关键词 SVM Semi-tensor product STP-kernel NONLINEAR CLASSIFICATION Reproducing kernel Hilbert space(RKHS)
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Rearrangement Inequality and Chebyshev's Sum Inequality on Positive Tensor Products of Orlicz Sequence Space with Banach Lattice 被引量:1
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作者 Wei-Kai Lai 《Journal of Mathematics and System Science》 2014年第8期574-578,共5页
Let φ be an Orlicz function that has a complementary function φ* and let lφ be an Orlicz sequence space. We prove a similar version of Rearrangement Inequality and Chebyshev's Sum Inequality in lφ FX, the Freml... Let φ be an Orlicz function that has a complementary function φ* and let lφ be an Orlicz sequence space. We prove a similar version of Rearrangement Inequality and Chebyshev's Sum Inequality in lφ FX, the Fremlin projective tensor product of lφ with a Banach lattice X, and in lφ iX, the Wittstock injective tensor product of lφ with a Banach lattice X. 展开更多
关键词 Rearrangement inequality Chebyshev's sum inequality injective tensor product projective tensor product Orlicz sequence space
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Rigidity Theorems of Riemannian Manifold with 2Ric=0
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作者 徐森林 梅加强 《Journal of Mathematical Research and Exposition》 CSCD 1998年第1期1-10,共10页
Ricci curvature tensor is denoted by Ric. We study when the manifold which satisfy 2Ric=0 become a Einstein manifold or a space form.
关键词 Ricci curvature tensor Riemann curvature tensor Einstein space weyl conformal curvature tensor scalar curvature.
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从黎曼流形的观点看非线性最小二乘平差 被引量:1
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作者 白亿同 《武汉测绘科技大学学报》 CSCD 1991年第4期78-84,共7页
本文从黎曼流形的观点出发研究了非线性最小二乘平差,并以张量作为工具导出了非线性最小二乘中的一些公式。
关键词 黎曼注形 最小二乘 平差 张量
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Einstein’s Pseudo-Tensor in <i>n</i>Spatial Dimensions for Static Systems with Spherical Symmetry
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作者 Frank R. Tangherlini 《Journal of Modern Physics》 2013年第9期1200-1204,共5页
It was noted earlier that the general relativity field equations for static systems with spherical symmetry can be put into a linear form when the source energy density equals radial stress. These linear equations lea... It was noted earlier that the general relativity field equations for static systems with spherical symmetry can be put into a linear form when the source energy density equals radial stress. These linear equations lead to a delta function energymomentum tensor for a point mass source for the Schwarzschild field that has vanishing self-stress, and whose integral therefore transforms properly under a Lorentz transformation, as though the particle is in the flat space-time of special relativity (SR). These findings were later extended to n spatial dimensions. Consistent with this SR-like result for the source tensor, Nordstrom and independently, Schrodinger, found for three spatial dimensions that the Einstein gravitational energy-momentum pseudo-tensor vanished in proper quasi-rectangular coordinates. The present work shows that this vanishing holds for the pseudo-tensor when extended to n spatial dimensions. Two additional consequences of this work are: 1) the dependency of the Einstein gravitational coupling constant κ on spatial dimensionality employed earlier is further justified;2) the Tolman expression for the mass of a static, isolated system is generalized to take into account the dimensionality of space for n ≥ 3. 展开更多
关键词 Field EQUATIONS Point Particle Dimensionality of space Einstein’s Pseudo-tensor
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Space-Time Curvature Mode Quanta
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作者 Philipp Kornreich 《Journal of Modern Physics》 2020年第12期1977-1992,共16页
Einstein theorized that Gravity is not a force derived from a potential that acts across a distance. It is a distortion of space and time in which we live by masses and energy. Consistent with Einstein’s theory, a mo... Einstein theorized that Gravity is not a force derived from a potential that acts across a distance. It is a distortion of space and time in which we live by masses and energy. Consistent with Einstein’s theory, a model of space-time curvature modes and associated curvature quanta in slightly warped space-time generated by a light Photon is derived. Both a Schr<span style="white-space:nowrap;">?</span>dinger and a Second Quantized representation of the space-time curvature mode quanta are calculated and are fourth rank tensors. The eigenvalues of these equations are radii of curvature, not energy. The Eigenfunctions are linear functions of the components of the tensor that describes the curvature of space-time. 展开更多
关键词 PHOTONS PHONONS GRAVITY General Relativity space-TIME Radius of Curvature tensor
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General Relativity without Curved Space-Time (&#8370;R)
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作者 Abed El Karim S. Abou Layla 《Journal of High Energy Physics, Gravitation and Cosmology》 2019年第1期156-166,共11页
The theory of general relativity is related to the concept of curvature of space- time induced by the presence of the massive objects. We will see through this paper that the general relativity can be linked with line... The theory of general relativity is related to the concept of curvature of space- time induced by the presence of the massive objects. We will see through this paper that the general relativity can be linked with linear Algebra and Vector Analysis without the need for concept of space-time. This is important for the unification of general relativity with quantum mechanics, gravity with electromagnetic, and a better understanding of the universe, gravity, black holes. The most important is the separation between the space-time and the big bang theory, which prove the existence of space-time before that, which leads to the existence of the creator of the universe. 展开更多
关键词 Gravity Electromagnetism BIG Bang space-TIME General RELATIVITY LORENTZ Force Density The Einstein’s tensor
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YANG-BAXTER OPERATORS AND TENSOR TRANSFORMATIONS
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作者 汪振华 《Acta Mathematica Scientia》 SCIE CSCD 2002年第3期427-432,共6页
The author considers relations between Yang-Baxter operators and tensor transformations, and proves that all tensor transform at ions over the category of modules of a Yang-space form a group.
关键词 Yang-Baxter operators Yang-space tensor transformations
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Higher-Dimensional Kaluza-Klein Theory in Weitzenbock Space
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作者 吴又麟 《Science China Mathematics》 SCIE 1993年第2期201-208,共8页
It is proved that the action of the higher-dimensional gravity in Weitzenb(?)ck space reduces to the sum of the action of gravity in four-dimensional space-time and that of gauge fields. In this sense we conclude that... It is proved that the action of the higher-dimensional gravity in Weitzenb(?)ck space reduces to the sum of the action of gravity in four-dimensional space-time and that of gauge fields. In this sense we conclude that in Weitzenb(?)ck space the higher-dimensional Kaluza-Klein theory holds. 展开更多
关键词 Weitzenbock space KALUZA-KLEIN theory parallel VECTOR FIELDS TORSION tensor.
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