近似计算

To match the boundary conditions, the modified Bessel functions are expanded to the planar wave in the interface. Then the eigenvalue equations of different polarizations are obtained by scalar approximation. At last, the relations between propagation losses and the states of polarizations, the geometric structures of the fiber, the refractive index and thickness of the polymer are calculated.

论文首先给出其等效折射率数学模型，在纤芯和包层中，光场用贝塞尔函数及虚宗量贝塞尔函数的求和表示，在聚合物和金属中用指数函数的求和表示，交界面上采用将虚宗量贝塞尔函数用平面波展开的方法匹配边界条件，然后利用标量近似求出极化D型光纤不同偏振态光场模式的本征值方程，最后通过数值计算得到光纤的传输损耗与抛磨平面和纤芯之间的距离，聚合物粘接材料的折射率和厚度，以及偏振态之间的关系。

Based on the theory of cosine crossing point, the combination of three-sector approximate cosine crossing point and regulation sampling to compute trigger angle on line was given.

根据余弦交点法的原理，提出了三段近似余弦同步波和规则采样结合的一种在线计算触发延迟角的方法。

In addition, laser Raman scattering and low temperature photoluminescence measurements are carried out, the GaSb-like LO mode, AlSb-like LO mode and the coupled mode between LO phonon and plasmon are observed. According to the dependence of the GaSb-like LO mode frequency on Al composition, an empirical formula was obtained for determining the Al composition.

用激光喇曼散射和低温光致发光研究了材料的光学性质，观察到了类GaSb的LO模和类AlSb的LO模以及LO声子与等离子体激元的耦合模L，并根据类GaSb的LO模随Al组分x的变化规律，得到一个计算Al组分的近似公式。

The results for the double-ayered show that, owing to the presence of concrete outer layer of the shell, the maximum boundary stress of steel is reduced to about 20—25%, and the pressure distribution between these two layers takes the sha...

在此基础上，作者提出了计算双层蜗壳的近似方法。在三夹层蜗壳的试验中，测量了内外层钢板的应力，发现这种结构不仅在工艺上有其特点，而且能在很大程度上消除蜗壳边界的应力高峯。

This paper introduces the theory,performance,characteristics and surveying process of three dimension laser scanning and mapping system,and discusses the application of this system in measuring crown volume,which regarding a tree crown as a combination of a great many circular truncated cones.

该文介绍了三维激光扫描系统的组成、工作原理及工作流程；探讨了应用三维激光扫描系统，通过扫描获取单株树木的三维空间点阵数据，将树冠近似为多个圆台体，求它们的体积之和来计算树冠体积的方法。

The differential cross section, the polarisation and the spin-rotationparameter in elastic scattering of 180 MeV antiproton by 12C are calculated by means ofGlauber s multiple scattering theory and Pauli-correlated wavefunction .

在Glauber多重散射理论近似下，采用泡里关联的核波函数，使用一种唯象的湮灭势，对180MeV的在12C上的弹性散射微分截面，极化角分布和自旋旋转参数进行了计算。

But the study of non-well-distributed substance of differency in nature in every direction has been ignored in the approximate solution of Voigt and Reuss, and as a result, it is not a overall conclusion.

针对各向异性非均匀体，采用变分法及能量极值原理进行分析，得出了一个比Voight -Reuss和Hashin -Shtrikman上、下限近似解更为精确和合理的上、下限计算公式

We don't make the rotating-waveapproximation and don't neglecte the coupling between the excitons with different wave vectorin our theortical calculation.

我们在理论计算中没有作旋波近似，也没有忽略不同波矢激子之间的耦合。

The results show that the rate of heating decreases due to the growth of oxidation layer in soaking process when the thermal resistance between gas and slab increases. The quantity of loss of iron scale increases with the increase of the coefficient of air consumption under the condition of certain soaking temperature. When the coefficient of air consumption is certain, the quantity of loss of iron scale increases with the increase of soaking temperature rapidly. The results of numerical simulation is consistent with experimental ones, and the error is very small within the range of soaking temperature in CSP line.

研究结果表明：在加热过程中生成的氧化层增大了换热热阻，使钢坯的加热速度减小；钢坯氧化烧损量随加热速度的增大而减小；当达到同一特定的均热温度时，钢坯氧化烧损量随空气消耗系数的增大近似呈线性递增；当空气消耗系数一定时，钢坯氧化烧损量随均热温度的提高而急剧增加；数值计算结果与实验结果变化趋势一致，并在CSP均热温度范围内较吻合。

It is found that both scalar and vector potentials of neutron in theneutron rich nuclear matter become stronger although the isospin dependence is notstronger.

利用这样的耦合常数在RMF近似下计算的核物质的结合能与DBHF结果会有偏离，因而得到的核状态方程也会有偏离，如在饱和点处结合能有小于2％的偏差。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。