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Curved Space-Time at the Planck Scale
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作者 Lewis Nash 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期167-179,共13页
This paper presents a physically plausible and somewhat illuminating first step in extending the fundamental principles of mechanical stress and strain to space-time. Here the geometry of space-time, encoded in the me... This paper presents a physically plausible and somewhat illuminating first step in extending the fundamental principles of mechanical stress and strain to space-time. Here the geometry of space-time, encoded in the metric tensor, is considered to be made up of a dynamic lattice of extremely small, localized fields that form a perfectly elastic Lorentz symmetric space-time at the global (macroscopic) scale. This theoretical model of space-time at the Planck scale leads to a somewhat surprising result in which matter waves in curved space-time radiate thermal gravitational energy, as well as an equally intriguing relationship for the anomalous dispersion of light in a gravitational field. 展开更多
关键词 Schwarzschild space-Time Continuum Mechanics Planck lattice Gravitational Radiation
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Lattices Associated with a Finite Vector Space
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作者 Mengtian Yue 《Applied Mathematics》 2014年第4期672-676,共5页
Let be a n-dimensional row vector space over a finite field For , let be a d-?dimensional subspace of . denotes the set of all the spaces which are the subspaces of and not the subspaces of except . We define the part... Let be a n-dimensional row vector space over a finite field For , let be a d-?dimensional subspace of . denotes the set of all the spaces which are the subspaces of and not the subspaces of except . We define the partial order on by ordinary inclusion (resp. reverse inclusion), and then is a poset, denoted by (resp. ). In this paper we show that both and are finite atomic lattices. Further, we discuss the geometricity of and , and obtain their characteristic polynomials. 展开更多
关键词 VECTOR space GEOMETRIC latticE Characteristic POLYNOMIAL
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<i>L</i>-Topological Spaces Based on Residuated Lattices
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作者 Zhudeng Wang Xuejun Liu 《Advances in Pure Mathematics》 2012年第1期41-44,共4页
In this paper, we introduce the notion of L-topological spaces based on a complete bounded integral residuated lattice and discuss some properties of interior and left (right) closure operators.
关键词 Residuated lattice L-Topological space Interior OPERATOR LEFT (Right) CLOSURE OPERATOR
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A Euclidean-Like Discrete Spacetime from the Unification of a Multitude of Hypercubic Lattices
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作者 Christiaan Theodorus de Groot 《Journal of Modern Physics》 2017年第8期1175-1189,共15页
An autonomous discrete space is proposed consisting of a huge number of four dimensional hypercubic lattices, unified along one of the four axes. The unification is such that the properties of the individual lattice a... An autonomous discrete space is proposed consisting of a huge number of four dimensional hypercubic lattices, unified along one of the four axes. The unification is such that the properties of the individual lattice are preserved. All the unifying axes are parallel, and the other axes have indeterminate mutual relations. The two kinds of axes are non-interchangeable resembling time and space of reality. The unification constitutes a framework without spatial properties. In case the axes with indeterminate relations are present at regular intervals in the time and the space, a Euclidean-like metric and goniometry can be obtained. In thus defined space-like structure, differences in speed and relativistic relations are only possible within regions of space enclosed by aberrations of the structure. 展开更多
关键词 DISCRETE space Hypercubic lattice spaceTIME ANISOTROPY Euclidean Metric RELATIVITY
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Physical Constants as Result of the Many Hypercubic Lattices of a Multidirectional Discrete Space
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作者 Christiaan T. de Groot 《Journal of Modern Physics》 2020年第3期432-447,共16页
A multidirectional discrete space consists of numerous hypercubic lattices each of which contains one of the spatial directions. In such a space, several groups of lattices can be distinguished with a certain property... A multidirectional discrete space consists of numerous hypercubic lattices each of which contains one of the spatial directions. In such a space, several groups of lattices can be distinguished with a certain property. Each group is determined by the number of lattices it comprises, forming the characterizing numbers of the space. Using the specific properties of a multidirectional discrete space, it is shown that some of the characterizing numbers can be associated with a physical constant. The fine structure constant appears to be equal to the ratio of two of these numbers, which offers the possibility of calculating the series of smallest numerical values of these numbers. With these values, a reasoned estimate can be made of the upper limit of the smallest distance of the discrete space of approximately the Planck length. 展开更多
关键词 Hypercubic lattice Multidirectional DISCRETE space Characterizing NUMBERS Fine Structure Constant Physical CONSTANTS PLANCK Length
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面向知识结构分析的模糊概念格模型 被引量:1
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作者 智慧来 李金海 《软件学报》 EI CSCD 北大核心 2024年第5期2466-2484,共19页
知识空间理论使用数学语言对学习者进行知识评价与学习指导,属于数学心理学的研究范畴.技能与问题是构成知识空间的两个基本要素,深入研究两者之间的关系是知识状态刻画与知识结构分析的内在要求.在当前的知识空间理论研究中,没有明确... 知识空间理论使用数学语言对学习者进行知识评价与学习指导,属于数学心理学的研究范畴.技能与问题是构成知识空间的两个基本要素,深入研究两者之间的关系是知识状态刻画与知识结构分析的内在要求.在当前的知识空间理论研究中,没有明确建立技能与问题之间的双向映射,从而难以提出直观概念意义下的知识结构分析模型,也没有明确建立知识状态之间的偏序关系,不利于刻画知识状态之间的差异,更不利于规划学习者未来的学习路径.此外,现有的成果主要集中在经典的知识空间,没有考虑实际问题中数据的不确定性.为此,将形式概念分析与模糊集引入知识空间理论,建立面向知识结构分析的模糊概念格模型.具体地,分别建立知识空间与闭包空间的模糊概念格模型.首先,建立知识空间模糊概念格,并通过任意两个概念的上确界证明所有概念的外延构成知识空间.引入粒描述的思想定义技能诱导的问题原子粒,由问题原子粒的组合判定一个问题组合是否是知识空间中的一个状态,进而提出由问题组合获取知识空间模糊概念的方法.其次,建立闭包空间模糊概念格,并通过任意两个概念的下确界证明所有概念的外延构成闭包空间.类似地,定义问题诱导的技能原子粒,由技能原子粒的组合判定一个技能组合是否是闭包空间中某一知识状态所需的技能,进而提出由技能组合获取闭包空间模糊概念的方法.最后,通过实验分析问题数量、技能数量、填充因子以及分析尺度对知识空间与闭包空间规模的影响.结论表明知识空间模糊概念不同于现有的任何概念,也不能从其他概念派生而来.闭包空间模糊概念本质上是一种面向属性单边模糊概念.在二值技能形式背景中,知识空间与闭包空间中的状态具有一一对应关系,但这种关系在模糊技能形式背景中并不成立. 展开更多
关键词 形式概念分析 知识空间理论 粒计算 粒描述 模糊概念格
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基于格密码的5G-R车地认证密钥协商方案
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作者 陈永 刘雯 张薇 《铁道学报》 EI CAS CSCD 北大核心 2024年第2期82-93,共12页
5G-R作为我国下一代高速铁路无线通信系统,其安全性对于保障行车安全至关重要。针对5G-AKA协议存在隐私泄露、根密钥不变和效率低等问题,基于格密码理论提出一种新型5G-R车地认证方案。首先,使用临时身份信息GUTI代替SUCI,克服了SUCI明... 5G-R作为我国下一代高速铁路无线通信系统,其安全性对于保障行车安全至关重要。针对5G-AKA协议存在隐私泄露、根密钥不变和效率低等问题,基于格密码理论提出一种新型5G-R车地认证方案。首先,使用临时身份信息GUTI代替SUCI,克服了SUCI明文传输的缺点。其次,设计基于格密码的根密钥更新策略,采用格上公钥密码体制、近似平滑投射散列函数和密钥共识算法,实现了根密钥的动态更新和前后向安全性。再次,加入随机质询和消息认证码,实现了通信三方的相互认证,可有效防范重放、DoS等多种恶意攻击。最后,采用串空间形式化方法进行安全验证,结果表明:本文方法较其他方法有更高的安全性,被攻击成功的概率最低,仅为O(n^(2))×2^(-128),且有较低的计算开销和通信开销,能够满足5G-R高安全性的需求。 展开更多
关键词 5G-R 车地认证密钥协商 格密码 前后向安全性 串空间模型
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一维超冷原子动量光晶格中的手征对称性破缺拓扑相
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作者 曾超 毛一屹 +3 位作者 吴骥宙 苑涛 戴汉宁 陈宇翱 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第4期21-26,共6页
对称性在理解物质的拓扑态方面具有关键作用.过去人们认为手征对称性保证了一维晶格的量子化Zak相位及其对应的非平庸拓扑相.本文展现了在一维手征对称性破缺的情况下,晶格系统仍具有量子化Zak相位和非平庸拓扑相.具体而言,在超冷原子... 对称性在理解物质的拓扑态方面具有关键作用.过去人们认为手征对称性保证了一维晶格的量子化Zak相位及其对应的非平庸拓扑相.本文展现了在一维手征对称性破缺的情况下,晶格系统仍具有量子化Zak相位和非平庸拓扑相.具体而言,在超冷原子动量晶格系统中有效地模拟了一个链长为26、手征对称性破缺的Zigzag模型,其中相等的次近邻耦合强度能够在保留空间反演对称性的同时破坏手征对称性.通过测量原子的时间平均波包位移来获得系统的拓扑不变量,并得到了其对应的量子化的Zak相位.此外,还观测到系统随着最近邻耦合强度比例的变化会从非平庸拓扑相转变为平庸拓扑相.本文不仅为对称性及拓扑相的相关研究提供了一个完全可控的平台,还可以通过控制格点间耦合强度和原子间相互作用,探索例如Tasaki,Aharonov-Bohm caging模型中的平带拓扑以及引入相互作用研究的非线性拓扑现象. 展开更多
关键词 对称性 拓扑不变量 Zak相位 动量光晶格
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基于依赖空间的对象导出三支概念格的属性约简
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作者 丁娜 马建敏 贺青青 《郑州大学学报(理学版)》 CAS 北大核心 2024年第1期68-74,共7页
在给定形式背景下,基于依赖空间提出了对象导出三支概念格属性约简的新定义,在此基础上讨论了属性约简方法。首先,借助三支算子定义了对象幂集上的一致关系,引入依赖空间。通过依赖空间生成闭包算子的闭元素,研究了闭元素和对象导出三... 在给定形式背景下,基于依赖空间提出了对象导出三支概念格属性约简的新定义,在此基础上讨论了属性约简方法。首先,借助三支算子定义了对象幂集上的一致关系,引入依赖空间。通过依赖空间生成闭包算子的闭元素,研究了闭元素和对象导出三支概念的外延之间的关系。其次,提出基于依赖空间的对象导出三支概念格属性约简的定义,该定义下的约简集是保持由原属性集确定的一致关系不变的最小属性子集。最后,给出协调集的判定定理,利用可辨识属性矩阵及辨识函数给出对象导出三支概念格的属性约简方法。 展开更多
关键词 对象导出三支概念格 一致关系 依赖空间 属性约简 可辨识属性矩阵
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并列双方柱绕流的Lattice Boltzmann模拟分析 被引量:10
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作者 饶勇 倪玉山 刘超峰 《应用力学学报》 EI CAS CSCD 北大核心 2008年第2期192-197,共6页
采用Lattice Boltzmann方法对并列双方柱绕流问题进行数值模拟。对方柱间距比s/D=0.2、0.3、0.4、0.5、1.0、1.4、1.5、1.6、1.8、2.0、2.5共11种情况下的流场分别进行计算,给出了对应的流线图、方柱的升力图及阻力图,同时计算了方柱各... 采用Lattice Boltzmann方法对并列双方柱绕流问题进行数值模拟。对方柱间距比s/D=0.2、0.3、0.4、0.5、1.0、1.4、1.5、1.6、1.8、2.0、2.5共11种情况下的流场分别进行计算,给出了对应的流线图、方柱的升力图及阻力图,同时计算了方柱各边中点的压力,给出了压力与间距比的变化曲线,并对各个流线图、升力图、阻力图及压力图进行了分析讨论。结果表明:当s/D≤1.5时,流动呈偏流型,形成周期漩涡;当s/D>1.5时,流动呈对称型,形成对称漩涡;s/D=1.5为流动从偏流型向对称型转换的临界间距比。该结果对工程中建筑物位置的安排及其安全系数的提高有一定的参考价值。 展开更多
关键词 latticE Bo[tzmann 方柱绕流 流场模拟 间距比
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From Dirac’s Aether to the Dirac Equation
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作者 Richard D. Bateson 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1450-1466,共17页
In 1951, Dirac proposed a formalism for a Lorentz invariant Aether with a vacuum state that contains all possible velocity states at each space-time point. Dirac showed no explicit path from the Aether towards the Qua... In 1951, Dirac proposed a formalism for a Lorentz invariant Aether with a vacuum state that contains all possible velocity states at each space-time point. Dirac showed no explicit path from the Aether towards the Quantum Mechanics. In this paper, we demonstrate that Dirac’s proposed Aether can be described by a lattice of possible events in space-time built in the local Lorentz frame. The idealised case of single velocity state leads to the famous Dirac equation for a plane wave state and is compatible with quantum statistics. On the lattice, possible space-time events are connected by the Dirac spinors which provide the probability of observing an event. The inertial mass of a particle is shown to be equivalent to the density of possible events on the lattice. Variation of the lattice density of events modifies the metric and provides a space-time curvature leading to the Hilbert action associated with general relativity. In classical limit, the perturbation in the density of possible events of the Aether is proportional to the Newtonian gravitational potential. 展开更多
关键词 Dirac Aether Lorentz Invariance Dirac Equation Quantum Mechanics space-Time lattice Dirac Spinors Inertial Mass Metric Modification space-Time Curvature General Relativity
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Variable dimensional state space based global path planning for mobile robot 被引量:1
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作者 张浩杰 陈慧岩 +6 位作者 姜岩 龚建伟 熊光明 陈慧岩 姜岩 龚建伟 熊光明 《Journal of Beijing Institute of Technology》 EI CAS 2012年第3期328-335,共8页
A variable dimensional state space(VDSS) has been proposed to improve the re-planning time when the robotic systems operate in large unknown environments.VDSS is constructed by uniforming lattice state space and gri... A variable dimensional state space(VDSS) has been proposed to improve the re-planning time when the robotic systems operate in large unknown environments.VDSS is constructed by uniforming lattice state space and grid state space.In VDSS,the lattice state space is only used to construct search space in the local area which is a small circle area near the robot,and grid state space elsewhere.We have tested VDSS with up to 80 indoor and outdoor maps in simulation and on segbot robot platform.Through the simulation and segbot robot experiments,it shows that exploring on VDSS is significantly faster than exploring on lattice state space by Anytime Dynamic A*(AD*) planner and VDSS is feasible to be used on robotic systems. 展开更多
关键词 variable dimensional state space lattice state space Anytime Dynamic A*(AD*) path planning
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GENERALIZATIONS AND CARTESIAN CLOSED SUBCATEGORIES OF SEMICONTINUOUS LATTICES 被引量:4
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作者 李庆国 伍秀华 《Acta Mathematica Scientia》 SCIE CSCD 2009年第5期1366-1374,共9页
In this article, the authors mainly study how to obtain new semicontinuous lattices from the given semicontinuous lattices and discuss the conditions under which the image of a semicontinuous projection operator is al... In this article, the authors mainly study how to obtain new semicontinuous lattices from the given semicontinuous lattices and discuss the conditions under which the image of a semicontinuous projection operator is also semicontinuous. Moreover, the authors investigate the relation between semicontinuous lattices and completely distributive lattices. Finally, it is proved that the strongly semicontinuous lattice category is a Cartesian closed category. 展开更多
关键词 semicontinuous lattices strongly semicontinuous lattices semicontinuous mapping HEREDITARY function space Cartesian closed category
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YET ON LINEAR STRUCTURES OF NORM-ATTAINING FUNCTIONALS ON ASPLUND SPACES
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作者 程立新 罗思捷 《Acta Mathematica Scientia》 SCIE CSCD 2018年第1期151-156,共6页
In this paper, we show that if an Asplund space X is either a Banach lattice or a quotient space of C(K), then it can be equivalently renormed so that the set of norm- attaining functionals contains an infinite dime... In this paper, we show that if an Asplund space X is either a Banach lattice or a quotient space of C(K), then it can be equivalently renormed so that the set of norm- attaining functionals contains an infinite dimensional closed subspace of X* if and only if X* contains an infinite dimensional reflexive subspace, which gives a partial answer to a question of Bandyopadhyay and Godefroy. 展开更多
关键词 norm-attaining functional Asplund space Banach lattice reflexive subspace Banach space
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Remark on Regularity of Continuous Operators on AL-Spaces
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作者 冯勋省 陈滋利 《Journal of Southwest Jiaotong University(English Edition)》 2004年第1期79-82,共4页
Let E and F be Banach lattices. It is known that if every continuous linear operator from E into F is regular, then, under some mild assumptions on E or F, either E is lattice isomorphic to an AL-space or F is lattice... Let E and F be Banach lattices. It is known that if every continuous linear operator from E into F is regular, then, under some mild assumptions on E or F, either E is lattice isomorphic to an AL-space or F is lattice isomorphic to an AM-space. Here we present a characterization on an AL-space E such that every bounded linear operator from E into a Banach lattice is regular. A counterexample is also provided, which shows that the results are unexpected even if the domain is an AL-space or the range space is an AM-space. 展开更多
关键词 Banach lattice AL-space AM-space ATOMICITY REGULARITY
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The Universe at Lattice-Fields 被引量:1
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作者 Giovanni Guido Gianluigi Filippelli 《Journal of High Energy Physics, Gravitation and Cosmology》 2017年第4期828-860,共33页
We formulate the idea of a Universe crossing different evolving phases where in each phase one can define a basic field at lattice structure (Uk) increasing in mass (Universe-lattice). The mass creation in Uk has a do... We formulate the idea of a Universe crossing different evolving phases where in each phase one can define a basic field at lattice structure (Uk) increasing in mass (Universe-lattice). The mass creation in Uk has a double consequence for the equivalence “mass-space”: Increasing gravity (with varying metric) and increasing space (expansion). We demonstrate that each phase is at variable metric beginning by open metric and to follow a flat metric and after closed. Then we define the lattice-field of intersection between two lattice fields of base into universe and we analyse the universe in the Nucleo-synthesis phase (intersection-lattice ) and in the that of recombination (intersection-lattice ). We show that the phase is built on the intersection of the lattices of the proton (Up) and electron (Ue) or . We show UH to be at variable metric (open in the past, flat in the present and closed in the future). Then, we explain some fundamental aspects of this universe UH: Hubble’s law by creating the mass-space in it, its age (13.82 million of Years) as time for reaching the flat metric phase and the value of critic density. In last we talk about dark universe lattice , having hadronic nature, and calculating its spatial step and its density in present phase of . 展开更多
关键词 space-TIME latticE NUCLEOSYNTHESIS Hydrogen UNIVERSE INTRINSIC Quantum Oscillator DARK Matter DARK Energy
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Nexus: A Quantum Theory of Space-Time, Gravity and the Quantum Vacuum
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作者 Stuart Marongwe 《International Journal of Astronomy and Astrophysics》 2013年第3期236-242,共7页
One of the main problems of contemporary physics is to find a quantum description of gravity. This present approach attempts to remedy the problem through the quantization of a finite but large flat Minkowski space-ti... One of the main problems of contemporary physics is to find a quantum description of gravity. This present approach attempts to remedy the problem through the quantization of a finite but large flat Minkowski space-time by means of Fourier expansion of the displacement four vector. By applying second quantization techniques, space-time emerges as a superposition of space-time eigen states or lattices of quantized space-time vibrations also known as gravitons. Each lattice element four vector is a graviton and traces out an elementary four volume (lattice cell). The stress-momentum tensor of each graviton defines its curvature and also the curvature of the associated lattice as described by General Relativity. The eigen states of space-time are found to be separated by a quantum of energy equal to the product of the Hubble constant and the Planck constant. The highest energy state is at Planck energies. This paper also shows that gravitons can be absorbed and emitted by the space-time lattice changing the volume of its primitive cells and that particles of observable matter are associated with a graviton whose frequency is equal to the particle’s Compton frequency which the lattice can absorb producing a perturbation in the lattice. The space-time lattice is found to be unstable and decays by radiating low energy gravitons of energy equal to the product of the Hubble constant and the Planck constant. This decay causes the space-time superstructure to expand. The graviton is seen a composite spin 2 particle made from a combination of spin half components of the displacement four vector elements. The spin symmetry of its constituent elements can breakdown to give rise to other vector or scalar bosons. Dark Matter is seen as a consequence of Bose-Einstein statistics of gravitons which results in some regions of the lattice having more energy than others. 展开更多
关键词 lattice space-TIME Graviton DARK Energy DARK MATTER General RELATIVITY
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MONOTONE POINTS IN ORLICZ-BOCHNER SEQUENCE SPACES
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作者 Wanzhong Gong Zhongrui Shi 《Analysis in Theory and Applications》 2012年第4期301-311,共11页
In Orlicz-Bochner sequence spaces endowed with Orlicz norm and Luxemburg norm, points of lower monotonicity, upper monotonicity, lower local uniform monotonicity and upper local uniform monotonicity are characterized.
关键词 Banach lattice Orlicz-Bochner space Luxemburg norm Orlicz norm upper(lower) monotone point upper (lower) locally uniformly monotone point
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Geometrical Modeling of Crystal Structures with Use of Space of Elliptic Riemannian Geometry
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作者 Stanislav Rudnev Boris Semukhin Andrey Klishin 《Materials Sciences and Applications》 2011年第6期526-536,共11页
The space of internal geometry of a model of a real crystal is supposed to be finite, closed, and with a constant Gaussian curvature equal to unity, permitting the realization of lattice systems in accordance with Fed... The space of internal geometry of a model of a real crystal is supposed to be finite, closed, and with a constant Gaussian curvature equal to unity, permitting the realization of lattice systems in accordance with Fedorov groups of transformations. For visualizing computations, the interpretation of geometrical objects on a Clifford surface (SK) in Riemannian geometry with the help of a 2D torus in a Euclidean space is used. The F-algorithm ensures a computation of 2D sections of models of point systems arranged perpendicularly to the symmetry axes l3, l4, and l6. The results of modeling can be used for calculations of geometrical sizes of crystal structures, nanostructures, parameters of the cluster organization of oxides, as well as for the development of practical applications connected with improving the structural characteristics of crystalline materials. 展开更多
关键词 F-Algorithm Crystal latticE Systems Microstructure RIEMANNIAN Geometry space of Interpretation
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Notes on Preregular Operators in Banach Lattices
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作者 陈芳 陈滋利 《Journal of Southwest Jiaotong University(English Edition)》 2009年第4期363-365,共3页
Some characterizations of preregular operators between two Banach lattices are presented. Then several sufficient conditions for preregular operators being regular are given, and some related results are also obtained.
关键词 Banach lattice Property (P) Dedekind complete KB-space Regular operator Preregular operator
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