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1.
Plane waves in a semi-infinite fluid saturated porous medium   总被引:5,自引:0,他引:5  
The field equations governing the propagation of waves in an incompressible liquid-saturated porous medium are investigated and a general solution is presented. It has been revealed that coupled longitudinal and transverse waves propagate in the porous medium. The propagation of transverse waves in the fluid phase is completely due to the interaction between the solid and fluid phases. The dispersion relationship and attenuation features are discussed. Unlike other investigations, all explicit forms of the arguments are derived. The reflection of the plane harmonic waves at the plane, traction-free boundary, which shows the influence of the dissipation on the velocity, and the attenuation coefficients of the reflected waves is studied. It is of interest that pore pressure is produced in the process of reflection, even in the case of the incidence of transverse waves.  相似文献   
2.
陈伟民  江毅 《光子学报》1998,27(2):127-131
本文根据光纤光栅多传感器复用时信号的光谱特征,提出了采用成象光谱技术对复用信号进行解调的方案.文章推导分析了该复用方案的有关参量及特性,并进行了验证实验,获得了与计算结果吻合的实验结果.  相似文献   
3.
增强金属-氧化物-金属隧道结的光发射   总被引:1,自引:0,他引:1  
本文报道通过改进制作工艺将A1-A12O3-Au隧道结的耐压增加到5.3V,发光外量子效率增加到8.2×10-4,均高过迄今见到的关于该类结的最高耐压和最高效率的报道。我们观测到了该发光结上的Au膜厚度对发射光谱形状的影响,并对此作出了解释;还对该光谱中的截止频率和峰值的存在给出了理论解释。  相似文献   
4.
江毅  陈伟民 《发光学报》1997,18(1):46-50
本文采用了一种简单的功率监测法,观察了KrF准分子激光对掺锗光纤折射率影响的非线性过程。观察到子纤芯折射率扰动过程中非稳定现象、饱和现象和折射率扰动的非线性。  相似文献   
5.
We compute the electric dipole moment generated at two-loop for the W-boson in the Weinberg-Higgs model in which the CP violation is mediated by neutral Higgs-boson exchange. We also compare our results with the others relative to the problem in the literature  相似文献   
6.
How to increase the speed in drawing and recognizing curves has always been a major concern. From the Breshenham Algorithm and DDA Algorithm in the sixties to the double-step and quadruple-step line generation iu the eighties, curves were all dragon point by point. The algorithm in this paper fully utilizes machine commands to accelerate the generation of lines and curves. We introduce and prove for the first time characterization theorems of the segment code order of digital lines and curyes. These theorems give new methods in the recognition and the measure of smoothness of lines and curves.  相似文献   
7.
喻洪麟  何安国 《光子学报》1994,23(3):251-254
本文提出了一种高分辨率小型光电编码器的高密度圆光栅制作新工艺和高倍细分法。  相似文献   
8.
In view of the nature of orderness in structure and the mesomorphism in property of liquid crystal, the function of which is further exploited by integrating it with the feature of crown ether. The monoarmed crown ether liquid crystals are successfully applied to the imitation of biomembrane transport. Binary component membrane composed of crown ether liquid crystal and PVC was first developed. Such a novel model of biomimetic membrane is capable of imitating ingeniously the thermocontrolling transport of biomembrane, thus the essential function of liquid crystal in membane transport is more fully exploited. It was suggested, consequently, that the molecules of the crown ether liquid crystal could assemble themselves to form ionic channels, as they exist in mesophase.Of still more significance is that the thermocontrolling transport of ions through the membrane is found to be operative selectively and the permeation of ion is under the direct influence of the thermal turmoil of the crown ether liquid cr  相似文献   
9.
结构模糊有限元平衡方程的一种新解法*   总被引:18,自引:2,他引:16  
本文将区间数方程组解的定义与结构有限元平衡方程的力学意义结合起来,针对由于材料性能的模糊性、结构边界条件的模糊性和载荷的模糊性而得到的模糊有限元平衡方程组.提出了一种快速而准确的解法,其计算量与普通有限元法几乎相等.  相似文献   
10.
模糊随机有限元平衡方程的摄动解法*   总被引:23,自引:3,他引:20  
对模糊随机有限元平衡方程作λ水平截集,得随机区间平衡方程,然后基于平衡方程中有关力学量之间的关系,将随机区间平衡方程转化为两类普通随机平衡方程求解,利用小参数摄动理论导得求随机区间位移的递归方程组.文中还详细推导了计算模糊随机位移、模糊随机应变和模糊随机应力数字特征的计算公式.  相似文献   
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