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991.
Kumar Yagyesh Mishra Rishi Panwar Ekta Kaur Jaswinder Panwar Ravi 《Optical and Quantum Electronics》2019,51(10):1-11
Optical and Quantum Electronics - We have investigated the potential of using the E-field induced birefringence for improving the sensitivity of uniaxial anisotropic slab waveguide sensor based on... 相似文献
992.
S. Kaur 《Opto-Electronics Review》2019,27(1):10-13
The welcome and adaptation of optical wireless technology by the modern era has brought forward the concept of an inter-satellite free-space optical communication system. In the present work, I study the combined effect of selection of different operating wavelengths and detector types along with the pointing errors at the transmitter and receiver side on the performance of an inter-satellite free-space optical link. The link performance has been optimized by measuring and analyzing the bit error rate and quality-factor of received signal under different scenarios. Performance of the inter-satellite link has also been investigated considering different modulation formats and data rates for LEO and MEO distances. 相似文献
993.
Six isomeric dimethyl anilinium bromides (DMABr) have been prepared and characterized by elemental and spectroscopic studies.
Thermal decomposition of these salts has been studied by TG and simultaneous TG-DTA techniques. Kinetic parameters have been
evaluated from isothermal TG data using contracting area and contracting cube equations. The decomposition pathways have also
been suggested which involves simultaneous sublimation (at lower temperature) and dissociative vaporization/decomposition
(at higher temperature).
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
994.
Effect of nonthermal ion distribution and dust temperature on nonlinear dust acoustic solitary waves 总被引:1,自引:0,他引:1
The effects of nonthermal ion distribution and finite dust temperature are incorporated in the investigation of nonlinear
dust acoustic waves in an unmagnetized dusty plasma. Sagdeev pseudopotential method which takes into account the full nonlinearity
of plasma equations, is used here to study solitary wave solutions. Possibility of co-existence of refractive and compressive
solitons as a function of Mach number, dust temperature and concentration of nonthermal ions, is considered. For the fixed
value of nonthermal ions, it is found that the effect of increase in dust temperature is to reduce the range of co-existence
of compressive and refractive solitons. Particular concentration of nonthermal ions results in disappearance of refractive
solitons while the decrease in dust temperature, at this concentration restores the lost refractive solitons. 相似文献
995.
Meenu Thakur B. R. Behera Ruchi Mahajan N. Saneesh Gurpreet Kaur Priya Sharma R. Dubey Kushal Kapoor A. Yadav Neeraj Kumar S. Kumar Kavita Rani P. Sugathan A. Jhingan A. Chatterjee M. B. Chatterjee S. Mandal A. Saxena Santanu Pal S. Kailas Avazbek Nasirov Bakhodir Kayumov 《The European Physical Journal A - Hadrons and Nuclei》2017,53(6):133
996.
In the present work,nonlinear interaction of elliptical laser beam with collisional plasma is studied by using paraxial ray approximation.Nonlinear differential equations for the beam width parameters of semi-major axis and semi-minor axis of elliptical laser beam have been set up and solved numerically to study the variation of beam width parameters with normalized distance of propagation.Effects of variation in absorption coefficient and plasma density on the beam width parameters are also analyzed.It is observed from the analysis that extent of self-focusing of beam increases with increase/decrease in plasma density/absorption coefficient. 相似文献
997.
In this paper, the governing relations and equations are derived for nonlocal elastic solid with voids. The propagation of time harmonic plane waves is investigated in an infinite nonlocal elastic solid material with voids. It has been found that three basic waves consisting of two sets of coupled longitudinal waves and one independent transverse wave may travel with distinct speeds. The sets of coupled waves are found to be dispersive, attenuating and influenced by the presence of voids and nonlocality parameters in the medium. The transverse wave is dispersive but non-attenuating, influenced by the nonlocality and independent of void parameters. Furthermore, the transverse wave is found to face critical frequency, while the coupled waves may face critical frequencies conditionally. Beyond each critical frequency, the respective wave is no more a propagating wave. Reflection phenomenon of an incident coupled longitudinal waves from stress-free boundary surface of a nonlocal elastic solid half-space with voids has also been studied. Using appropriate boundary conditions, the formulae for various reflection coefficients and their respective energy ratios are presented. For a particular model, the effects of non-locality and dissipation parameter (\(\tau \)) have been depicted on phase speeds and attenuation coefficients of propagating waves. The effect of nonlocality on reflection coefficients has also been observed and shown graphically. 相似文献
998.
Artificial Neural Networks are developed as an important technique for equalization and have been widely used to mitigate the nonlinear effects in coherent optical systems. For the compensation of nonlinearities in coherent optical orthogonal frequency division multiplexing technique, the most popular artificial neural network model is a multilayer perceptron (MLP), as it is able to perform complex mapping between input and output spaces with significant success. However due to the complexity of multilayer perceptron nonlinear equalizer (MLP-NLE) model training of neural network is difficult. To overcome computational complexity issues of MLP-NLE, a single neuron based functional link artificial neural network nonlinear equalizer (FLANN-NLE) has been developed in this paper. Better performance of an equalizer is attributed to the usage of aPSO-BP algorithm for training the FLANN-NLE. The proposed FLANN-NLE surpasses the existing works both in terms of Q-Factor and computational complexity. For a fiber length of 1000 km and at launch power of ?6 dBm, the improvement in Q-Factor is approximately equal to 3.3 and 1 dB in contrast to the previously reported values of approximately 3 and 0.7 dB at bit rate of 40 and 80 Gbps respectively. 相似文献
999.
The heterogeneous features of the supercooled state over different time regimes are explored in a self-consistent mode-coupling mode. The exponent a for the mean-square displacement approximately t(a), of a tagged particle is computed. The non-Gaussian parameter alpha(2)(t) shows a peak in the short time regime in addition to a second peak over longer times. The position of the short-time peak in alpha(2)(t) hardly shifts, while that of the other grows with density. 相似文献
1000.
The imines generated in situ from 2-pyridinecarboxaldehyde/2-quinolinecarboxaldehyde and aryl amines undergo indium-mediated Barbier allylation in aqueous media to provide homoallylic amines. Crotyl and cinnamyl bromides lead to diastereoselective allylation with d.r. up to 98:2. 相似文献