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161.
We proposed a novel kinetic energy decomposition analysis based on information theory. Since the Hirshfeld partitioning for electron densities can be formulated in terms of Kullback–Leibler information deficiency in information theory, a similar partitioning for kinetic energy densities was newly proposed. The numerical assessments confirm that the current kinetic energy decomposition scheme provides reasonable chemical pictures for ionic and covalent molecules, and can also estimate atomic energies using a correction with viral ratios. 相似文献
162.
163.
It is shown that the probability law of a diffusion process conditioned on weakly corrupted observations is asymptotically Gaussian when properly scaled. The method of proof involves Fisher information matrices and a Cramér-Rao inequality. 相似文献
164.
系统阐述了我国两化融合的本质、发展规律、阶段特征、实现途径,总结了两化融合在我国的实践和发展,最后提出了若干政策建议。通过理论研究和总结,为践行具有中国特色的两化融合之路提供借鉴和参考。 相似文献
165.
Chinese calligraphy is a unique visual art, and is still emitting fascinating artistic brilliance and charm. The artistic beauty of Chinese calligraphy is constituted by two elements, i.e., form and spirit, which attract continual attentions by calligraphy artists. In this paper, we present Shear-Guided filter to extract the artistic information. Shear-Guided filter is designed by combining the shear transformation and the guided filter. It has both the edge-preserving smoothing property from the guided filter and the linear multidirectional property from the shear transformation. Shear-Guided filter can extract more spirit information from the calligraphy images, especially in the half-dry strokes. Furthermore, the previous evaluation parameters consider all pixels equally, which is against the truth. Here we put forward three new parameters to solve this issue. Finally, experiments show that Shear-Guided filter can extract the information of form and spirit more accurately, and the new evaluation parameters have better performances in evaluation. 相似文献
166.
167.
Robert Vallée 《International Journal of Mathematical Education in Science & Technology》2013,44(2):141-144
Inside the scientific world it is not always understood that the mood of mathematics, which is a product and a part of culture, can change with time. This is partly why many have been surprised by the coming of the so‐called new mathematics. In the truly creative mathematical mind two opposite tendencies coexist: the logical and the imaginative. Apparently it seems that new mathematics can be reduced to a purely logical machinery. In fact it contains as much imaginative contributions as classical mathematics. But it is difficult to show simultaneously the logical sequence of propositions and the clumsy progression of research itself. Mathematical exposition does not always follow the ‘ most natural slopes’ of the mind. Unfamiliar presentations often give an impression of ‘ abstraction ‘, more familiar ones an impression of concreteness ‘. So it appears that difficulties with new mathematics are mostly of psychological origin. Misuses of it can easily raise up intolerance reactions and emotional blocks. Perhaps insisting upon the fact that, here as elsewhere, it is important to be able to guess, to realize that intuition and imagination are essential, could help to make new mathematics better understood, more useful and more able to be considered as a unifing element among sciences. 相似文献
168.
Takuya Yamano 《Entropy (Basel, Switzerland)》2021,23(3)
An electron in a constant magnetic field has energy levels, known as the Landau levels. One can obtain the corresponding radial wavefunction of free-electron Landau states in cylindrical polar coordinates. However, this system has not been explored so far in terms of an information-theoretical viewpoint. Here, we focus on Fisher information associated with these Landau states specified by the two quantum numbers. Fisher information provides a useful measure of the electronic structure in quantum systems, such as hydrogen-like atoms and under some potentials. By numerically evaluating the generalized Laguerre polynomials in the radial densities, we report that Fisher information increases linearly with the principal quantum number that specifies energy levels, but decreases monotonically with the azimuthal quantum number m. We also present relative Fisher information of the Landau states against the reference density with , which is proportional to the principal quantum number. We compare it with the case when the lowest Landau level state is set as the reference. 相似文献
169.
企业的竞争归根结底是人才的竞争,如何全面掌握和合理利用人才资源是公司人力资源管理的首要问题。本文首先简单介绍了数据挖掘技术的背景、常用技术及运作流程,在此基础上阐述了数据挖掘技术在人力资源信息系统中的应用。 相似文献
170.