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Journal of Visualization - The increasing availability of spatiotemporal data provides unprecedented opportunities for understanding the structure of an urban area in terms of people’s... 相似文献
3.
Acoustical Physics - The paper studies the evolution of a pulsed signal initiated by the pushing of a cylindrical piston and propagating through a stationary fluid filling a buried pipeline with an... 相似文献
4.
In this article, the effect of ionization on the energy spectrum of electrons within the interaction of a laser pulse with hydrogen atoms is investigated using particle-in-cell simulation codes. The results show that the behaviour of electrons' energy distribution function in the field-ionized plasma, which occurred due to the field ionization, compared with that in the pre-plasma strongly depends on the pulse shape. For short rise-time pulses (here 30 fs), due to the rapid enhancement of laser electric field, ionization occurs quickly, and as a result, there is not much difference in the electron energy in both the media. However, for pulses with rise time of 40 fs, in the pre-plasma state, the electron population reaches higher energies compared with the field-ionized plasma state. The main reason for this difference is the nonlinear wave breaking that happens earlier due to density inhomogeneity in the field-ionized plasma. On the other hand, at longer rise-time pulses (here 60 and 70 fs), electrons achieve higher energies in the field-ionized plasma than those in the case of pre-plasma. In this case, because of density fluctuations in the field-ionized plasma, the Raman backscattered radiations are seeded by a strong initial noise at the earlier times and the Mendonca condition for chaos threshold is met sooner. Therefore, the electrons gain more energy through the stochastic mechanism that is in agreement with chaotic nature of the motion. 相似文献
5.
Kazei Z. A. Snegirev V. V. Stolyarenko M. S. 《Journal of Experimental and Theoretical Physics》2021,133(5):591-598
Journal of Experimental and Theoretical Physics - The structural (lattice metric) and elastic characteristics of ErBaCo4O7 + x cobaltites, which are subjected to different heat treatment and are... 相似文献
6.
Journal of Algebraic Combinatorics - APR tilts for path algebra kQ can be realized as the mutation of the quiver Q in $${\mathbb Z}Q$$ with respect to the translation. In this paper, we show that... 相似文献
7.
Mokshin A. V. Khusnutdinoff R. M. Vilf Ya. Z. Galimzyanov B. N. 《Theoretical and Mathematical Physics》2021,206(2):216-235
Theoretical and Mathematical Physics - In the framework of the concept of time correlation functions, we develop a self-consistent relaxation theory of the transverse collective particle dynamics... 相似文献
8.
Experimental Mechanics - Ratcheting is an important mechanical behavior of metals and alloys, which is caused by the repeated accumulations of tensile and compressive strain in circle load.... 相似文献
9.
We generalize the P(N)-graded Lie superalgebras of Martinez-Zelmanov. This generalization is not so restrictive but suffcient enough so that we are able to have a classification for this generalized P(N)-graded Lie superalgebras. Our result is that the generalized P(N)-graded Lie super-algebra L is centrally isogenous to a matrix Lie superalgebra coordinated by an associative superalgebra with a super-involution. Moreover, L is P(N)-graded if and only if the coordinate algebra R is commutative and the super-involution is trivial. This recovers Martinez-Zelmanov's theorem for type P(N). We also obtain a generalization of Kac's coordinatization via Tits-Kantor-Koecher construction. Actually, the motivation of this generalization comes from the Fermionic-Bosonic module construction. 相似文献
10.
Alawainati F. A. Manaa H. Henari F. Z. Biyiklioglu Z. Arslan T. Jaafar A. 《Journal of Applied Spectroscopy》2021,88(5):951-957
Journal of Applied Spectroscopy - Detailed measurements of nonlinear optical properties and optical limiting for four phthalocyanine (Pc) derivatives (PcCo, PcCu, PcMn, and PcSi) are reported. The... 相似文献