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31.
考虑二维SBq方程组与Zakharov方程组的初边值问题,采用Galerkin方法和紧致性原理及能量估计,证明了这些问题整体强解的存在唯一性. 相似文献
32.
René Chambon 《Journal of Engineering Mathematics》2005,52(1-3):53-61
When they are studied as continuum media, granular materials and other soils and rocks exhibit a complex behavior. Contrary
to metals, their isotropic and deviatoric behavior are coupled. This implies some mathematical difficulties concerning boundary-value
problems solved with constitutive equations modelling the salient features of such geomaterials. One of the well-known consequences
is that the so-called second-order work can be negative long before theoretical failure occurs. Keeping this in mind, the
starting point of this work is the pioneering and illuminating work of Nova (1994), who proved that using an isotropic hardening
elasto-plastic model not obeying the normality rule, it is possible to exhibit either loss of uniqueness or loss of existence
of the solution of a boundary-value problem as soon as the second-order work is negative. Because the geomaterial behavior
is quite difficult to model, in practice many different constitutive equations are used. It is then important to study the
point raised by Nova for other constitutive equations. In this paper, his result is generalized for any inelastic rate-independent
constitutive equation. Similarly the link between localization and controllability proved by Nova (1989) is extended to some
extent to a general inelastic model. 相似文献
33.
34.
35.
在一系列假定条件下,建立了一个低渗透非达西气体渗流的非线性移动边界偏微分方程数学模型,在理论上论证模型解的存在唯一性基础上,用对数网格对求解区域进行剖分,建立显式预测隐式校正格式,进而讨论模型的算法。此模型和算法具有一定的应用价值。 相似文献
36.
稀疏效应下一类捕食者与食饵系统极限环 总被引:1,自引:0,他引:1
蔡淑云 《吉林化工学院学报》2002,19(4):95-97
研讨了稀疏效应下一类捕食者与食饵系统 :x· =x(x(r-x) -y) ,y· =b0 y(x -m) .讨论了该系统平衡点的性态 ,并证明了该系统极限环的存在性和唯一性 . 相似文献
37.
通过分析掌纹、指纹、虹膜、人脸、步态、声纹等生物特征识别技术的特点以及煤矿现场对入井人员生物特征的影响,指出虹膜识别、人脸识别、步态识别、声纹识别适用于煤矿入井人员唯一性检测;提出了一种基于人员定位和生物特征识别的煤矿入井人员唯一性检测技术方案,将生物特征识别技术嵌入人员定位系统,利用人员定位识别卡实现识别卡数量及人员身份的唯一性检测;指出煤矿入井人员唯一性检测技术的研究关键点是严重污染人脸的识别算法、对设备遮挡情况下人员步态图像的采集及对混入人员语音信号的煤矿现场噪声消除算法。 相似文献
38.
Halo effects in rating specific pieces of work, as in educational grading, have received little attention. Grades awarded by 2 independent graders to undergraduate projects were analyzed with a correlated uniqueness model. Grades showed substantial halo despite being awarded by expert assessors at the time of reading the work. There was greater halo between different grades applying to the same section of the project than between grades applying to different sections. Supervisors who had regular contact with the student whose work they were grading showed no more halo than other graders. More reliable graders showed less within-section halo than graders of lower reliability but equal between-sections halo. The halo effects observed cannot be entirely attributable to a unitary general impression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
39.
R. Vodi
ka V. Manti
F. París 《International journal for numerical methods in engineering》2006,66(12):1884-1912
A study of the removal of the non‐uniqueness in the solution of elastostatic problems by means of the symmetric Galerkin boundary element method is presented. The paper focuses on elastic problems defined on domains with cavities, where cavity boundaries are subjected to traction boundary conditions. A simple method consisting in a direct application of support conditions and several methods based on the Fredholm theory of linear operators are introduced, implemented and analysed. Numerical examples demonstrate the performance of the proposed methods and accuracy of their results, a comparative evaluation of the methods developed being finally presented. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
40.
图象重建的最小距离算法 总被引:2,自引:0,他引:2
本文提出了图象重建的一种凸集投影算法.它的重建图象是所有满足投影约束的图象中与先验图象的距离最小者.该算法是就连续分布的图象导出的,重建图象时也不需在空域与频域间进行变换,是一种较OSPR方法更直接、更简单的方法.还对最小距离算法重建结果的存在性、唯一性、幂等性等性质作了证明. 相似文献