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111.
Hong-jun Liu Wei Zhao Guo-fu Chen Yi-shan Wang Lian-jun Yu Chi Ruan Xue-feng Li 《Optics & Laser Technology》2004,36(4):3482-314
Experimental investigations of a type-I noncollinear phase-matched optical parametric amplification based on lithium triborate, which was pumped by a 5-ns second-harmonic pulses from a Q-switched Nd:YAG, seeded by a cw Ti:sapphire laser at 800 nm, was presented. The experiments generated 2-ns signal output pulses at 800 nm, the maximum signal output pulse energy reached 19 μJ, the corresponding parametric gain was 44 dB. Furthermore, the experiments demonstrate that the 65 nm-FWHM parametric fluorescence gain spectrum could also be observed. A quantitative account of the ultrabroadband parametric fluorescence gain spectrum was given with our theory. The experimental measurements are in agreement with theoretical calculations. 相似文献
112.
Dynamic systems described by nonlinear differential equations of the second order are studied. It is assumed that certain
preliminary information on the dissipative or elastic characteristics of systems is known. A new approach is demonstrated
to obtaining full information on unknown or partially known characteristics of a system from measurements of not only displacements
but also velocities and accelerations
__________
Published in Prikladnaya Mekhanika, Vol. 41, No. 6, pp. 139–143, June 2005. 相似文献
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Yoshiaki Yasuno Yasunori Sutoh Shuichi Makita Masahide Itoh Toyohiko Yatagai 《Optical Review》2003,10(5):498-500
A spectral interferometric optical coherence tomography (OCT) system which has polarization sensitivity is developed. This system reduces the mechanical scanning dimension by employing the principle of spectral interferometry, and measures a two dimensional cross-sectional image of biological tissue with one dimensional mechanical scanning. Sixteen OCT images with different polarization conditions are measured, and two dimensional distributions of each element of the Müller matrix of a sample to be measured are calculated. 相似文献
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The educational system has gradually shifted from a face-to-face to an e-learning system, which has become prevalent in advanced countries with the advance of information technology, and connection of global networks. Accordingly, a growing demand is emerging for more reliable individual certification with technical precision in order to measure and record learning achievements and credentials of participants. The present system has a limit in terms of registration capacity, therefore, its accuracy has often been questioned. Against this background, an individual certification system is proposed particularly for access control in e-learning. Under our proposed system, a compact optical correlator for facial recognition is employed. This correlator was previously tested for of biometrics authentication accuracy and proved highly reliable, having recorded remarkably low error rates (below 1%). The recorded error rate is sufficiently robust that the system itself can be regarded as a valid and practical viable attestation system. 相似文献
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考虑带调和势的超临界非线性Schroedinger方程,解决了该方程整体解和爆破解存在所依赖的初始条件的最佳分界门槛.通过构造两类强制变分问题和建立局部不变半流,运用势井方法和凹方法,获得了该方程在两个不同的空间中的整体解和爆破解的最佳门槛条件. 相似文献