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991.
一类含参变量积分的常差分方程计算方法 总被引:1,自引:0,他引:1
梅宏 《数学的实践与认识》2007,37(9):184-189
首次利用常差分方程方法计算了一类形如∫0πa+co bs cnoxs xdx(n∈N,a,b∈R)的含非负整数参数n与实数a,b的积分,且得到了完整的积分公式. 相似文献
992.
A. V. Latyshev A. A. Yushkanov 《Computational Mathematics and Mathematical Physics》2007,47(1):118-125
An analytical solution of the linearized problem concerning the behavior of collisional non-degenerate plasma in an external electric field is obtained. It is assumed that the electrons are diffusively scattered from the plasma boundary. The resulting solution is used to determine the screening field. The case of a high-frequency external field with a frequency close to the plasma resonance frequency is examined. 相似文献
993.
Lü Tianquan Liu Zhiguo Zheng Zhiren Huang Jian Su Wenhui 《Optical and Quantum Electronics》2004,36(4):389-397
Based on the dynamic equations of an electro-optic bistable system with delay in its feedback loop, we theoretically investigate second-order effects of the output resonance and frequency-locking of the system. 相似文献
994.
The kinetics of olive wood carbonization is investigated by means of isothermal thermogravimetric analysis method. Measurements were carried out in a thermobalance for different fixed temperatures between 498 and 648 K. A two-stage semi-global kinetic model consisting of four sequential steps was proposed to derive kinetic parameters. The olive wood is classified in three pseudo-components. For the first two, similar thermal degradation mechanisms take place in a single reaction step. For the third, the thermal degradation takes place in two consecutive steps. The isothermal conditions allow the kinetic constants (activation energy and pre-exponential factors) to be estimated by means of the analytical solution of the mass conservation equations. An overall good agreement was obtained with activation energy values available in the literature. 相似文献
995.
Antonino Mazzaglia Luigi Monsu' Scolaro Raphael Darcy Ruth Donohue Bart Jan Ravoo 《Journal of inclusion phenomena and macrocyclic chemistry》2002,44(1-4):127-132
The entanglement process between porphyrins and some amphiphiliccyclodextrins and the occurrence of different species have been proved by the combination of UV-Visabsorption, fluorescence anisotropy, resonance light scattering and 1H NMR spectroscopy. 相似文献
996.
Nitric acid (HNO3) plays an important role in the Earth’s atmosphere as a reservoir molecule of NOx species. It has a strong infrared signature at 11 μm which is one of the most commonly used for the infrared retrieval of this species in the atmosphere since this spectral region coincides with an atmospheric window. It is therefore essential to have high quality spectral parameters in this spectral region. For the H14NO3 (main) isotopic species, the 11 μm bands were already the subject of numerous extensive studies which involve not only the ν5 and 2ν9 cold bands but also the first hot bands. The present work is the first high resolution Fourier transform analysis of the 11 μm bands for H15NO3, which is the second most abundant isotopomer of nitric acid [a ≅ 0.00365(7)]. In this way, the analysis of the ν5 and 2ν9 cold bands centered at 871.0955 and 893.4518 cm−1 was performed, and as for H14NO3, these bands are significantly perturbed since rather strong resonances couple the 51 and 92 rotational levels. The theoretical model that we used to compute the line positions and line intensities is directly issued from the one which we used recently for H14NO3 [A. Perrin, J. Orphal, J.-M. Flaud, S. Klee, G. Mellau, H. Mäder, D. Walbrodt, M. Winnewisser, J. Mol. Spectrosc. 228 (2004) 375-391]. Actually, for the H15NO3 line positions, the Hamiltonian matrix accounts for the rather strong Fermi and the weaker Coriolis interactions linking the 51⇔92 rotational levels. Using this model which accounts correctly for the strong mixing of the 51 and 92 upper state energy levels, the ν5 and 2ν9 line intensities for H15NO3 were satisfactorily computed using the ν5 and 2ν9 transition moment operators achieved previously for the 14N (main) isotopic species. In this way, the transfer of intensities from the ν5 fundamental (and presumably strong) band to the 2ν9 overtone (and presumably weak) band could be explained for H15NO3 as it was done previously for the 14N (main) isotopic species. Finally, the position of the H15NO3ν5 + ν9 − ν9 hot band was identified at 875.245 cm−1. 相似文献
997.
In this work, we show that the capture into parametric resonance may be explained as pitchfork bifurcation in the primary
parametric resonance equation. We prove that the solution close to the moment of the capture is descibed by the Painlevé-2
equation. We obtain connection formulae for the asymptotic solution of the primary parametric resonance equation before and
after the capture using the matching of asymptotic expansions. 相似文献
998.
α-Actinin has been shown to be capable of interacting with some special membrane phospholipids directly, which is important for its function. In this study, hybrid bilayer membranes composed of negatively charged lipids are constructed on the surface plasmon resonance gold substrate and on the gold electrode, respectively, and the interaction between α-actinin and negatively charged lipids membrane is investigated by surface plasmon resonance, cyclic voltammetry and electrochemical impedance spectroscopy methods. α-Actinin is proved to be able to interact with the negatively charged lipids membrane directly. It can also insert at least partly into the membrane or lead to some defect or lesion in the membrane, which increase the permeability of the membrane. This study would bring some insight on the interaction between the α-actinin and the cell membranes in vivo. 相似文献
999.
Collective unidirectional motion of an asymmetrically coupled array of oscillators in symmetric periodic potentials is studied. A directed current is observed when the drift coupling is presented, while no external biased force is applied. Negative directed current is found when varying system parameters. An addition of a periodic rocking force may enhance the efficiency of directed transport. Resonant steps of the current are found and interpreted as the mode locking between the array and the ac force. Noise-assisted transport is observed, and an optimal noise intensity can give rise to a most efficient transport. The directed transport thus can be optimized and furthermore controlled by suitably adjusting the parameters of the system. 相似文献
1000.
Y. Zhang 《Journal of Optimization Theory and Applications》2007,132(1):111-124
Most research in robust optimization has been focused so far on inequality-only, convex conic programming with simple linear
models for the uncertain parameters. Many practical optimization problems, however, are nonlinear and nonconvex. Even in linear
programming, the coefficients may still be nonlinear functions of the uncertain parameters. In this paper, we propose robust
formulations that extend the robust-optimization approach to a general nonlinear programming setting with parameter uncertainty
involving both equality and inequality constraints. The proposed robust formulations are valid in a neighborhood of a given
nominal parameter value and are robust to the first-order, thus suitable for applications where reasonable parameter estimations
are available and uncertain variations are moderate.
This work was supported in part by NSF Grant DMS-0405831 相似文献