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151.
We perform a multiple-time scales analysis and compatibility condition to the regularized long-wave (RLW) equation. We derive Korteweg-de Vries (KdV) flow equation in the bi-Hamiltonian form as an amplitude equation.  相似文献   
152.
This article presents a Taylor collocation method for the approximate solution of high‐order linear Volterra‐Fredholm integrodifferential equations with linear functional arguments. This method is essentially based on the truncated Taylor series and its matrix representations with collocation points. Some numerical examples, which consist of initial and boundary conditions, are given to show the properties of the technique. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2011  相似文献   
153.
In this study, a Hermite matrix method is presented to solve high‐order linear Fredholm integro‐differential equations with variable coefficients under the mixed conditions in terms of the Hermite polynomials. The proposed method converts the equation and its conditions to matrix equations, which correspond to a system of linear algebraic equations with unknown Hermite coefficients, by means of collocation points on a finite interval. Then, by solving the matrix equation, the Hermite coefficients and the polynomial approach are obtained. Also, examples that illustrate the pertinent features of the method are presented; the accuracy of the solutions and the error analysis are performed. © 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 27: 1707–1721, 2011  相似文献   
154.
155.
A cationic gold carbonyl complex has been synthesized and characterized using several techniques including X-ray crystallography. [(Mes(3)P)Au(CO)][SbF(6)] (Mes = 2,4,6-Me(3)C(6)H(2)) has a linear, two-coordinate gold atom. This compound displays the CO stretching frequency at 2185 cm(-1). The (13)C NMR signal of the gold-bound (13)CO appears as a doublet centered at δ 182.6 ((2)J(C,P) = 115 Hz). A computational study shows that the Au-CO bond consists of electrostatic attraction, Au ← CO donation, and significant Au → CO π-back-bonding components. Polarization of the CO bond caused by the electrostatic effect of the cationic gold center is mainly responsible for the large blue shift in the CO stretching frequency.  相似文献   
156.
BorderSense: Border patrol through advanced wireless sensor networks   总被引:1,自引:0,他引:1  
The conventional border patrol systems suffer from intensive human involvement. Recently, unmanned border patrol systems employ high-tech devices, such as unmanned aerial vehicles, unattended ground sensors, and surveillance towers equipped with camera sensors. However, any single technique encounters inextricable problems, such as high false alarm rate and line-of-sight-constraints. There lacks a coherent system that coordinates various technologies to improve the system accuracy. In this paper, the concept of BorderSense, a hybrid wireless sensor network architecture for border patrol systems, is introduced. BorderSense utilizes the most advanced sensor network technologies, including the wireless multimedia sensor networks and the wireless underground sensor networks. The framework to deploy and operate BorderSense is developed. Based on the framework, research challenges and open research issues are discussed.  相似文献   
157.
The electronic properties of metal-organic semiconductor-inorganic semiconductor structure between GaAs and poly(3,4-ethylenedioxithiophene)-block-poly(ethylene glycol) organic film have been investigated via current-voltage and capacitance-voltage methods. The Au/PEDOT/n-GaAs contact exhibits a rectification behavior with the barrier height of 0.69 eV and ideality factor value of 3.94. The barrier height of the studied diode (0.67 eV) is lower than that of Ni/n-GaAs/In (0.85 eV) and Au/n-GaAs/In Schottky diodes. The decrease in barrier height of Au/n-GaAs/In Schottky diode is likely to be due to the variation in the space charge region in the GaAs. The obtained results indicate that control of the interfacial potential barrier for metal/n-GaAs diode was achieved using thin interlayer of the poly(3,4-ethylenedioxithiophene)-block-poly(ethylene glycol).  相似文献   
158.
We present the first systematic study of cyanobiphenyls (CBs) and the phenylcyclohexanes in the range between 50 cm-1 (1.5 THz) and 500 cm-1 (15 THz). The impact of the alkyl chain length and of variations in the core structure on the spectrum is investigated using liquid crystals from the cyanobiphenyl and phenylcyclohexane families. Our measurements are supported by calculations based on density functional theory. This enables us to shine light on the vibrational dynamics of liquid crystal molecules in the terahertz frequency range.  相似文献   
159.
160.
The notion of Darboux helix in Euclidean 3‐space was introduced and studied by Yayl? et al. 2012. They show that the class of Darboux helices coincide with the class of slant helices. In a special case, if the curvature functions satisfy the equality κ2 + τ2 = constant, then these curves are curve of the constant precession. In this paper, we study Darboux helices in Euclidean 4‐space, and we give a characterization for a curve to be a Darboux helix. We also prove that Darboux helices coincide with the general helices. In a special case, if the first and third curvatures of the curve are equal, then Darboux helix, general helix, and V4‐slant helix are the same concepts.  相似文献   
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