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101.
Changqing?XuEmail author Ren?DingEmail author 《Discrete and Computational Geometry》2004,31(4):655-663
A finite planar set is k-isosceles for k 3 if every
k-point subset of the set contains a point equidistant from the
other two. In [1] Fishburn obtains several important results
about isosceles planar sets and poses a series of conjectures and
open questions. We disprove Conjecture 1 in [1] and provide
another 34 nonsimilar 4-isosceles 8-point planar sets which answer
one of the open questions in [1] negatively. 相似文献
102.
The ground state properties of Cd, Sn and Te isotopes are investigated in the framework of the Skyrme-Hartree-Fock theory using the normal force parameters SKI2 plus density-dependent pairing correlations and new force parameters SKI4 which has a generalized spin-orbit term [P. G. Reinhard and H. Flocard, Nucl. Phys. A 584 (1995) 467]. The theoretical results agree well with experimental data of binding energies and matter root-mean-square radii of charge distributions. Both parameter sets are also successful in reproducing the experimental law of isotope shifts in Cd and Sn elements. The behavior of isotope shifts in Te elements is predicted. We have made detailed comparison and discussion on the numerical results and given an explanation for the cause of above success. 相似文献
103.
Kinetic energy(KE) functional is crucial to speed up density functional theory calculation. However, deriving it accurately through traditional physics reasoning is challenging. We develop a generally applicable KE functional estimator for a one-dimensional (1D) extended system using a machine learning method. Our end-to-end solution combines the dimensionality reduction method with the Gaussian process regression, and simple scaling method to adapt to various 1D lattices. In addition to reaching chemical accuracy in KE calculation, our estimator also performs well on KE functional derivative prediction. Integrating this machine learning KE functional into the current orbital free density functional theory scheme is able to provide us with expected ground state electron density. 相似文献
104.
The fundamental equation of the thermodynamic system gives the relation between the internal energy, entropy and volume of two adjacent equilibrium states. Taking a higher-dimensional charged Gauss–Bonnet black hole in de Sitter space as a thermodynamic system, the state parameters have to meet the fundamental equation of thermodynamics. We introduce the effective thermodynamic quantities to describe the black hole in de Sitter space. Considering that in the lukewarm case the temperature of the black hole horizon is equal to that of the cosmological horizon, we conjecture that the effective temperature has the same value. In this way, we can obtain the entropy formula of spacetime by solving the differential equation. We find that the total entropy contains an extra term besides the sum of the entropies of the two horizons. The corrected term of the entropy is a function of the ratio of the black hole horizon radius to the cosmological horizon radius, and is independent of the charge of the spacetime. 相似文献
105.
It is proved that the Bergman type operatorT, is a bounded projection from the pluriharmonic Bergman spaceL
p
(B)∩h(B) onto Bergman spaceL
p
(B) ∩
H(B) for 0p 1 ands (p1-1)(n+1). As an application it is shown that the Gleason’s problem can be solved in Bergman space LP(B)∩H(B) for 0p 1.
Project supported by the National Natural Science Foundation of China (Grant No. 19871081) and the Doctoral Program Foundation
of the State Education Commission of China. 相似文献
106.
Yanbo B. Ren 《Acta Mathematica Hungarica》2012,134(1-2):169-176
We apply function parameters, which was introduced by T.?F. Kalugina, to interpolation between martingale Hardy spaces. Some new interpolation theorems for Lorentz martingale spaces are proved. 相似文献
107.
The reaction of 2,5-dimethylfuran (DMF) with H-atoms was studied using a potential energy surface calculated at the CBS-QB3 level of theory and master equation/RRKM modeling. Hydrogen abstraction by H-atom and hydrogen additions on DMF were considered. As the decomposition pathways of the initial adducts were unknown, a large number of decomposition routes was explored for these adducts. An important number of interconnected product channels were found and preliminary master equation calculations were performed to select the crucial wells and exit channels. The ipso substitution DMF + H → methylfuran (MF) + CH3 and the formation of 1,3-butadiene and acetyl radical (CH3CO) were found to be the major product channels in the addition process. The total calculated rate constant was found in good agreement with experimental data and is nearly pressure-independent. A small sensitivity to pressure was found for the computed branching ratios. At 1 bar, the yields of the two product channels of the addition process are maximal at 1100 K with computed branching ratios of 39% (MF + CH3) and 27% (1,3-C4H6 + CH3CO). Above 1300 K, hydrogen abstraction by H-atom becomes dominant and reaches a branching ratio of 56% at 2000 K. 相似文献
108.
一类非线性算子的带误差的Ishikawa迭代程序及其稳定性 总被引:2,自引:0,他引:2
倪仁兴 《高校应用数学学报(A辑)》2001,16(3):309-316
建立了任意实Banach空间中带误差的Ishikawa迭代程序逼近Lipschitz强伪压缩算子的不动点的一般性定理,指出已被广泛广泛研究的Ishikawa迭代序列的稳定性问题仅是带误差的Ishikawa迭代程序的特例,作为直接的应用,用不同于通常的方法证得任意实Banach空间中的Ishikawa迭代序列关于Lipschitz强伪压缩算子是稳定的,这些推广或发展了近期许多相应的结果。 相似文献
109.
110.
Yuntao Wu Dongzhou Ding Shangke Pan Fan Yang Junyan Shi Guohao Ren 《Journal of luminescence》2012,132(2):251-255
Lu0.8Sc0.2BO3 crystals doped with 1 at%Ce3+ and co-doped 0.1 at% and 0.5 at%Pr3+ were grown by the Czochralski method. The concentrations of Pr3+ and Ce3+ in crystals were measured by the ICP-AES method. Absorption spectra, VUV–UV spectra, fluorescence decay time and X-ray excitation luminescence spectra were investigated at room temperature. The excitation luminescence spectra of Ce3+ emission and decay curves from the lower excited state levels of the 4f15d1 and 5d1 electronic configurations of the Pr3+ and Ce3+ conspicuously indicated the non-radiative energy transfer from Pr3+ to Ce3+. The detailed pathways were shown in the energy level diagram of the respective Ce3+ and Pr3+ in Lu0.8Sc0.2BO3 host. In addition, the scintillation efficiency data indicated that the energy transfer effect is directly associated with the Pr3+ concentration. 相似文献