不能接近的

The results were found as following:(1) The damage value increases more significantly with the increase in PVF before 30% PVF, beyond which the increasing trend becomes gradually gentle.(2)Keeping the interphase strength and PVF unchanged, the damage increase with increasing moisture concentration in a nearly linear relation.(3)The results generated from the FCC model with consideration of the interphase debonding are in good agreement with the experimental data, meanwhile, the FCC model is also capable of predicting the critical load for the damaged and the undamaged dental composite subject too the 3-point flexural test.4 A 3D-fmite element analysis has been successfully exploited to examine the mechanical behavior of the restoration-tooth structure under the polymerization shrinkage and water sorption. It was found:(1) The low stiffness of the composite has the effect to limit the displacement occurring in the remaining tooth tissue. For lower interphase, the cuspal flexures are litter higher. The high interphase modulus acts as a \'shielding effect\' for stress transfer.

得到如下结论：(1)相同的吸湿性，在30％PVF(颗粒体积分数：Particle volume fraction，PVF)前增加PVF，层间脱胶损伤值显著增加；此后损伤值的增加趋于平缓；(2)保持层间强度和PVF不变，层间脱胶损伤随吸湿率的增加而接近线性增加；(3)FCC(面心立方：Face-centred cubic，FCC)模型层间脱胶损伤的预测结果和实验数据基本吻合；同时此模型可以用于预测牙齿填充材料三点弯曲实验的临界载荷。4、建立理想牙齿修复结构，利用有限元方法研究了同时考虑聚合收缩和吸湿膨胀耦合作用下的填充修复材料和粘结界面层材料性能对牙齿修复结构的力学行为的影响，得到如下结论：(1)低弹性模量的牙齿填充修复材料能限制天然牙组织的位移，但天然牙组织的位移与粘结界面层的弹性模量无关。

Chapter 8: We discuss the acceleration of multigrid by Krylov subspace approaches, and recognize the reason for slow convergence of algebraic multigrid methods is that error reduction is significantly less efficient for some very specific error components which may cause a few eigenvalues of the algebraic multigrid iteration matrix to be considerably closer to 1 than all the rest. However, the eigenvectors belonging to the few isolated eigenvalues can be expected to be typically captured after only a few conjugate gradient iterations, which accelerate algebraic multigrid algorithms. Theoretical analysis and numerical results of some practical problems show the iterant recombination accelerates algebraic multigrid convergence.

第八章：先介绍用Krylov子空间迭代法加速一般多重网格方法收敛的基本框架，然后紧紧抓住引起代数多重网格方法收敛减慢的根本原因往往是误差减小对几个特别的误差分量不明显，这导致代数多重网格方法的迭代矩阵的几个特征值接近于1，而共轭梯度方法则能比较典型地捕捉属于孤立特征值的特征向量，从而推导出有效的共轭梯度加速算法和程序实现，不仅从一些具体的实际应用例子的数值结果去验证迭代复合加速收敛的效果，而且还从理论上分析了预处理共轭梯度法加速代数多重网格法收敛的机理。

Having carried on my work thus far with so little obligation to any favourer of learning, I shall not be disappointed though I should conclude it, if less be possible, with less; for I have been long wakened from that dream of hope, in which I once boasted myself with so much exultation, my Lord, your Lordship's most humble, most obedient servant

迄今为止，我的工作所得到的学界领袖的帮助接近于无，我对此并不失望，即使帮助变得更少，我也能完成我的工作。尊敬的伯爵，我早就不做美梦了，在那些梦里，我曾一度洋洋得意的自诩为您最谦卑和服从的仆人

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐