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71.
72.
L^p- L^q decay estimate of solution to Cauchy problem of a linear thermoviscoelastic system is studied. By using a diagonalization argument of frequency analysis, the coupled system will be decoupled micrologically. Then with the help of the information of characteristic roots for the coefficient matrix of the system, L^p- L^q decay estimate of parabolic type of solution to the Cauchy problem is obtained. 相似文献
73.
关于非牛顿流体衰减性的一个注记 总被引:1,自引:0,他引:1
In the study of long time asymptotic behaviors of the solutions to a class system of the incompressible non-Newtonian fluid flows in R3, it is proved that the weak solutions decay in L2 norm at (1+t) and the error of difference between non-Newtonian fluid and linear equation is also investigated. The findings are mainly based on the classic Fourier splitting methods. 相似文献
74.
研究Kac方程的初值问题.证明了该类方程存在唯一的全局分布解.并且使用一种新的线性化方法证明了该类方程的解具有相应的多项式衰减性. 相似文献
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Point Sources and Gaussian beams are used frequently as fundamental building blocks for developing ultrasonic beam models. Both these models have different weaknesses that limit their effectiveness. Here, we will show that one can develop a Gaussian Beam Equivalent Point Source (GBEPS) model that removes those weaknesses and combines the accuracy and versatility of the point source models with much of the speed and well-behaved nature of Gaussian beam models. We will demonstrate the efficiency and versatility of this new GBEPS model in simulating the beams generated from ultrasonic phased arrays, using as few as one Gaussian beam per element of the array. A single element GBEPS model will be shown to be as accurate as a point source model even when substantial beam focusing or steering is present in the array or where the array beam is transmitted through an interface. At the same time the GBEPS model will be shown to be several orders of magnitude faster than the point source model. 相似文献
78.
本届会议的专题报告按日程安排分述如下:(1)T Wacharalindu:以液态半导体为基础的微功率源--采用反射能量转换;(2)C M Waits,MMc Carthy,R Ghodea:供小规模动力系统中输送燃料用的、微电动机械系统的涡轮泵;(3)I D Block、P c Mcthals、M Ganoch:增强荧光与无标记成像联用仪;(4)L H Loo、Y D Lau:应用微结构的流体动力学偶联方法进行微型悬臂的质量因子的调谐;(5)K Imagawa,H Horilauchi,K Ikoda:应用心脏肌肉细胞的药物模拟方法的自给加热与流体泵送凝胶;(6)N Suhkl:供模拟在任何硅取向的表面组织与几何形态用的连续分格自动化技术. 相似文献
79.
This paper presents a novel non-contact method for evaluating the resonant frequency of a microstructure, Firstly, the microstructure under test is excited by ultrasonic waves. This excitation method does not impose any undefined load on the specimen like the electrostatic excitation and also this is the first actual use of ultrasonic wave for exciting a microstructure in the literature. Secondly, the amplitudes of the microstructure are determined by image edge detection using a Mexican hat wavelet transform on the vibrating images of the microstructure. The vibrating images are captured by a CCD camera when the microstructure is vibrated by ultrasonic waves at a series of discrete high frequencies (〉30 kHz). Upon processing the vibrating images, the amplitudes at various excitation frequencies are obtained and an amplitude-frequency spectrum is obtained from which the resonant frequency is subsequently evaluated. A micro silicon structure consisting of a perforated plate (192 × 192 μm) and two cantilever beams (76 × 43 μm) which is about 4 μm thickness is tested. Since laser interferometry is not required, thermal effects on a test object can be avoided. Hence, the setup is relatively simple. Results show that the proposed method is a simple and effective approach for evaluating the dynamic characteristics of microstructures. 相似文献
80.