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31.
Avrutskiy V. I. Ishkhanyan A. M. Krainov V. P. 《Theoretical and Mathematical Physics》2021,208(3):1201-1206
Theoretical and Mathematical Physics - The fractional derivative method is used to take wave dispersion into account in the wave equation when describing the propagation of gravitational soliton... 相似文献
32.
Juan D. Gomez William G. P. Mayner Maggie Beheler-Amass Giulio Tononi Larissa Albantakis 《Entropy (Basel, Switzerland)》2021,23(1)
Integrated information theory (IIT) provides a mathematical framework to characterize the cause-effect structure of a physical system and its amount of integrated information (). An accompanying Python software package (“PyPhi”) was recently introduced to implement this framework for the causal analysis of discrete dynamical systems of binary elements. Here, we present an update to PyPhi that extends its applicability to systems constituted of discrete, but multi-valued elements. This allows us to analyze and compare general causal properties of random networks made up of binary, ternary, quaternary, and mixed nodes. Moreover, we apply the developed tools for causal analysis to a simple non-binary regulatory network model (p53-Mdm2) and discuss commonly used binarization methods in light of their capacity to preserve the causal structure of the original system with multi-valued elements. 相似文献
33.
In this paper, we design a Branch and Bound algorithm based on interval arithmetic to address nonconvex robust optimization problems. This algorithm provides the exact global solution of such difficult problems arising in many real life applications. A code was developed in MatLab and was used to solve some robust nonconvex problems with few variables. This first numerical study shows the interest of this approach providing the global solution of such difficult robust nonconvex optimization problems.
相似文献34.
Siberian Mathematical Journal - We obtain some new estimates that show the extremality of the Rademacher system in the set of sequences of independent functions considered in rearrangement... 相似文献
35.
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
36.
Radiophysics and Quantum Electronics - This work is a review of recent results, which have been obtained within the framework of the mathematical theory of dynamical chaos and are related to the... 相似文献
37.
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
38.
Vysotskii S. L. Kozhevnikov A. V. Filimonov Yu. A. 《Physics of the Solid State》2021,63(10):1579-1583
Physics of the Solid State - The interference of excited and received by current antennae magnetoelastic waves counterpropagating in an yttrium iron garnet film is experimentally studied. It is... 相似文献
39.
Foundations of Computational Mathematics - We present a finite element variational integrator for compressible flows. The numerical scheme is derived by discretizing, in a structure-preserving way,... 相似文献
40.
Chong Saehwa Riley Brian J. Nienhuis Emily T. Lee Dongjin McCloy John S. 《Journal of chemical crystallography》2021,51(3):293-300
Journal of Chemical Crystallography - Four different rare-earth oxyapatites of Ca2RE8(SiO4)6O2 (RE?=?Pr, Tb, Ho, Tm) were synthesized using a solution-based method followed by drying,... 相似文献