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971.
根据河南省2017年统计数据,应用F-分析法对河南省11个地市区域创新能力进行聚类分析,验证了以专利授权数和发表论文数作为衡量区域创新能力指标的合理性;提出标准模型库的概念,构建F-识别模型,借助格贴近度和最大隶属原则,为其它城市区域创新能力的归类和识别提供了一种新的参考方法. 相似文献
972.
The cover image is based on the Research Article Pressure boundary condition in a multi-phase lattice Boltzmann method and its applications on simulations of two-phase flows by Lei Wang and Ze-Rui Peng, https://doi.org/10.1002/fld.4800 .
973.
We find that the Boltzmann weight of the three-dimensional Baxter-Bazhanov model is dependent on four spin variables which are the linear combinations of the spins on the corner sites of the cube, and the Wu-Kadanoff-Wegner duality between the cube- and vertex-type tetrahedron equations is obtained explicitly for the Baxter-Bazhanov model. Then a three-dimensional vertex model is obtained by considering the symmetry property of the weight function, which corresponds to the three-dimensional Baxter-Bazhanov model. The vertex-type weight function is parametrized as the dihedral angles between the rapidity planes connected with the cube. We write down the symmetry relations of the weight functions under the actions of the symmetry groupG of the cube. The six angles with a constraint condition appearing in the tetrahedron equation can be regarded as the six spectra connected, with the six spaces in which the vertextype tetrahedron equation is defined. 相似文献
974.
TheExistenceoftheCompleteandCompletelyDistributiveLatticesBatRuipu(白瑞蒲)(DepartmentofMathematics,HebeiUniversity,Baoding,07100... 相似文献
975.
976.
实二次代数整数环上的单位格的类数 总被引:2,自引:0,他引:2
用邻格方法及Siegelmass公式证明了实二次代数域Q(√d)上单位格种gen(In)n≥4)的类数h(In)=3当且仅当Q(√3):n=4;Q(√5);n=6;Q(√3);n=4;Q(√17):n=4. 相似文献
977.
The diffusion process of point particles moving on regular triangular and random lattices, randomly occupied with stationary scatterers (a Lorentz lattice gas cellular automaton), is studied, for strictly deterministic scattering rules, as a function of the concentration of the scatterers. In addition to the normal and various kinds of retarded diffusion found before on the regular square lattice, straight-line propagation through the scatterers is observed. 相似文献
978.
Coherent convergent beam electron diffraction is for the first time applied to the analysis of lattice fitting between vacuum-deposited PbTe and MgO thin crystals in the plan-view mode. The possibility of determination of the rigid-body shift is discussed on the basis of simulated diffraction patterns from the bi-crystals as well as the preliminary experimental results obtained by a 200 kV transmission electron microscope with a field emission electron gun. In the analysis, the importance of the position of interference fringes at overlaps of PbTe 200 and MgO 200 diffraction disks and that of the corresponding mirror symmetry in the whole pattern are emphasized in order to determine the rigid-body shift and the probe-position. 相似文献
979.
A discretization of the quantum mechanical phase space is presented in the context of q-noncommutative structures. We give two generalizations of the Heisenberg algebra in the arising lattice phase space. In contrast to ordinary quantum mechanics, there is, a priori, no systematic approach to an integrable oscillator Hamiltonian in lattice quantum mechanics. This is the central obstacle to deal with in this Letter. To do so, we show how in general the integrability of the harmonic oscillator is related to the Fourier transform between momentum and space variables. This will be done in both cases, the continuous and the discrete one. As an application, we finally obtain an integrable lattice Hamiltonian for the harmonic oscillator with generalized Hermite eigenfunctions. 相似文献
980.
E. M. Vechtomov 《Mathematical Notes》1997,62(5):575-580
The latticeA(X) of all possible subalgebras of the ring of all continuous ℝ-valued functions defined on an ℝ-separated spaceX is considered. A topological space is said to be a Hewitt space if it is homeomorphic to a closed subspace of a Tychonoff
power of the real line ℝ. The main achievement of the paper is the proof of the fact that any Hewitt spaceX is determined by the latticeA(X). An original technique of minimal and maximal subalgebras is applied. It is shown that the latticeA(X) is regular if and only ifX contains at most two points.
Translated fromMatematicheskie Zametki, Vol. 62, No. 5, pp. 687–693, November, 1997.
Translated by A. I. Shtern 相似文献