分叉

The results show that overpressure bench mark is well suited for describing anomaly distribution, and momentum bench mark can provide better measure for shockwave damage. Along with increasing of the branch deflexion angle, the primary tunnel momentum increases and the branch tunnel momentum decreases, and plane shockwave recover distance also increase but will not exceed six times equivalent diameter.

研究结果表明：超压准则适用于描述分布的不均性，而冲量准则能更好地衡量分叉巷道中冲击波的破坏作用；分叉角度的影响较大，随着分叉偏转角的增大，主巷道内冲量将增大而分巷道内冲量将减小，恢复"平面波"的距离也增大，但不超过6倍巷道等效直径。

The branch crack problems in a finite-width strip were solved by using the complex potential of a branch crack of half-plane, in which the distributed dislocations were assumed along all the branches arid one boundary of the strip.

假设沿分叉裂纹各分支和板条边界有某位错分布，利用半平面内分叉裂纹问题的复势函数，将板条分叉裂纹问题转化为半平面内的多分叉裂纹问题处理。

For the first time, we have applied this method to study the problem of bifurcations of map, including codimension one, codimension two and flip bifurcations.

本文将该方法推广至映射分叉问题的研究，包括余维一、余维二分叉和倍化分叉。

The emphasis was placed on the bifurcation problem of impact vibration systems, including codimension one and two bifurcations, flip bifurcations and Hopf bifurcations.

本文着重研究碰撞振动系统的分叉问题，包括余维一分叉、余维二分叉、倍化分叉和Hopf分叉等。

First of all, the method of Fredholm alternative is used to obtain the approximate solution of the first order for the bifurcating periodic solutions of a nonlinear system with delayed velocity feedback. The bifurcation direction and the stability of the bifurcating periodic solution are also determined.

首先，用Fredholm择一方法分析了一具有时滞速度反馈的非线性振动系统的Hopf分叉，得到了局部分叉周期解的近似表达式，确定了分叉解的分叉方向及稳定性。

In favour of arc length algorithm, the curve of fix points of balanced rotor to rotor speed, harmonious and subharmonious unbalance reponse curves are given. The Hopf bifurcation of balance rotor is computed by use of extent equation method.

同时应用扩展方程方法计算了平衡转子的Hopf分叉点，并用求得的Hopf分叉点参数进行数字仿真，证明极限环的存在，因此说明Hopf分叉点的计算是正确的。

As a result of analysis to many of the results of experiment, checked up on specimens, field investigation and combining with the theories of palaeobotany, comparative morphology, evolutional morphology of vascular plants and taxonomy, it can be concluded as following: the primitive sorts of Cycadaceae are the sorts that pinnate leafs are dichotomy; among these, the sort that pinnate leafs are tripinnate-dichotomy is most primitive, from this sort gradually evolve to bipinnate-dichotomy, to only for monopinnate-dichotomy, from this sort evolve to the sorts that pinnate leafs are simply pinna; among the sorts of simply pinna, the species that segments of megasporophyll possess much more triplicate to monodichotomy are most primitive.

经过大量的实验结果分析、查阅标本和野外调查，结合古植物学、比较形态学、演化植物学和分类学等理论进行分析，认为苏铁科原始的类型为羽叶呈二歧状分叉的种类，其中最原始的又是羽叶呈三回二歧状分叉的种类，从这个羽叶类型逐渐演化出一回二歧状分叉的羽叶类型，再演化出羽叶为单羽状的类型；而单羽状叶的类群中，又以大孢子叶侧裂片具三回、二回及一回二歧状分叉数量多的种类为最原始，而侧裂片二歧状分叉数量少的为较进化，侧裂片无二歧分叉的如拳叶苏铁类为最进化的种类。

The result shows that there is no Hopf bifurcation for the structure in inviscid fluids.

假设各板在同一时刻有相同的变形，建立了流体作用下简支板状梁的立方非线性模型，并利用Hopf分叉代数判据分析了简支板状梁流固耦合结构的分叉，结果表明该结构无Hopf分叉现象。

The carotid bifurcation on 8 sides had perforating arteries, and I l sides showed medial lenticulostriate artery of the middle cerebral arteries, with short course and overlapped with another perforating arteries upon entry into the anterior perforated substance.

豆纹动脉绝大部分从大脑中动脉M1段的分叉前段发出，但是大脑中动脉M1段的分叉越早，分叉后发出的穿通动脉越多。22侧半球存在大脑前动脉A1段的穿通动脉，进入前穿质时分支较多。

Results:(1) The two nerves were found anatomically related at 5～10 mm and 26～30 mm respectively following hypoglossal nerve entering the muscle.(2)The diameter of the two nerves were observed to match well with each other or with the main branches at 10 mm following the branching of hypoglossal nerve.(3) At 6～10 mm prior to the branching of hypoglossal nerve there was a branch going to the lingual muscles and plexiform of lingual nerve.

结果：(1)舌下神经与舌神经之间有二个恒定的联系部位，即舌下神经分支进入舌肌后最初5～10 mm处和26～30mm处；(2)舌下神经与舌神经最佳吻接部位，我们认为应在舌下神经主干分叉后10 mm左右；神经直径测量也发现神经直径与舌神经主干和分支直径较为匹配，且此区有利解剖，便于神经吻合；(3)舌下神经分叉之前，在神经干上方距分叉约6～10 mm处有一较固定分支，参与分布舌肌并与舌神经呈丛状结构。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。