粗化

• The relationship between the coarsening or refining operations and the combining operations of a belief structure are investigated . it is proved that the refining operation and two kinds of combining operations are both commutative with each other ; while the coarsening operation is only commutative with the disjunctive sum operation but not with the conjunctive sum operation . we pointed out the reason why th e coarsening operation and the conjunctive sum operation cannot be commutative
  讨论了信任结构的粗化和细化算子与信任结构的合成算子之间的关系，证明细化算子与两种合成算子均是可交换的；而粗化算子只与析取和算子可交换，却合取和算子不可交换，并指出了其不可交换的原因所在。
• In the long run , the economy beneficial of grassland claim is lower . the soil nutrition lose , mechanic compose become crude , vegetation restore is slow , the drought resisted ability is poor . therefore , it is not worth to claim grassland both from economy and ecology point of view
  长远来看，草地开垦经济效益低下，撂荒后又面临土壤养分流失、机械组成粗化、植被恢复缓慢、抗干扰能力弱等诸多生态问题，因此，无论从经济学还是生态学角度，开垦草地得不偿失。
• For a class of quadratic finite element diseretization systems of an elliptic boundary problem with jump coefficients under the unstructured quadrilateral grids , we are concerned with two kinds of quadratic lagrangian finite element equations , by analyzing the relationship between the linear finite element and quadratic finite element basis functions , a hew amg method is designed
  摘要针对一类带间断系数的椭圆边值问题，在非结构四边形剖分下，讨论了两种二次拉格朗日有限元方程的代数多重网格法，通过利用双线性元和二次元基函数之间的表示关系，给出了一种新的网格粗化算法和构造提升算子的代数途径。
• When the specimens are deformed in a long time at the optimal superplastic deformation condition , the microstructure is coarsened sharply . if the deformation time is shortened properly or the deformation temperature is decreased appropriately or strain rate is increased , homogeneous and fine equiaxed crystal microstructure can be obtained
  在最佳超塑性条件下长时间变形时，合金显微组织将发生明显粗化，适当缩短变形时间、或适当降低超塑变形温度及提高应变速率，可得到均匀细小的等轴组织。
• However , the die attach layer delaminated after 500 cycles and pcb cracked in the underfilled samples after long time cycling . c - sam is employed to investigate the delamination in the underfilled samples . highly concentrated stress - strain induced by the cte mismatch between the bga component and the pcb board , coarsened grain and two kinds of intermetallic compounds ( nisn / nisns ) which formed during reflow and thermal cycle and their impact on the reliability of solder joints are discussed in this paper
  充胶样品粗化尤为严重； ? ni - sn金属间化合物包括两层：其中，靠近ni焊盘的那层比较平整，同时， eds结果分析表明其化学式近似为nisn ，而靠近焊料的那层呈板条状，化学式近似为nisn _ 3 ，文献表明其为亚稳相； ?充胶使得样品最大应力范围降了接近一个数量级并降低了dnp的作用，同时，器件失效模式变为芯片粘接层分层； ? c - sam结果表明本论文采用的充胶样品，芯片粘接层分层起始于500周左右，而经过2700周循环的样品，分层几乎扩展到整个界面。
• The optical fiber surface pretreatment craft processes and the technological conditions have been determined through the experiment , various craft procedures which influence the electroless plating nickel - phosphorus alloy coating quality have been analyzed , the most attentions have been put on the coarsening and the activation craft which determine the electroless coating quality
  本文通过试验确定了光纤表面预处理的工艺流程及其工艺条件,分析了各工序对化学镀镍磷合金镀层质量的影响,重点研究了粗化及活化对化学镀层质量的影响。
• The organic matter , total n , hydrolytic n were increased , then reduced with the increase of abandoned time . the loss of organic c got up to 59 . 4 % in abandoned land . in 0 - 20cm , the sand content of 0 . 25 - 0 . 05mm was increased gradually , the average content of sand in the abandoned land was up to 76 . 84 % , the sand contents of silt and sand was gradually reduced , the soil mechanic compose became coarse
  随撂荒年限的增加，土壤有机质、全氮、碱解氮等主要养分均表现出先降低后增加的趋势；撂荒地有机碳的损失平均达到59 . 4 ；在撂荒地表面0 - 20cm范围内， 0 . 25 - 0 . 05mm粒径的砂粒含量逐渐增加，各撂荒地砂粒平均含量达76 . 84 ，粉粒和粘粒含量逐渐降低，土壤机械组成出现粗化现象。