s B 比 B is exceeded by A 好。
6)组织好句子，使动词尽量靠近主语，例如：
用 When the pigment was dissolved in dioxane , decolorization was irreversible after 10h of UV irradiation.
不用 The decolorization in solutions of the pigment in dioxane , which were exposed to 10h of UV irradiation , was no longer irreversible.
7)用重要的事实开头，尽可能避免用辅助从句开头，例如：
用 Power consumption of telephone suitching systems was determined from data obtained experimentally.
不用 From data obtained experimentally, power consumption of telephone suitching systems was determined.
7.取消或减少背景信息。背景信息如果过长或占文摘篇幅的比例过大，则反映出的就是对作者所做的工作描述过于笼统和简单。
8.作者在文献中谈及的未来计划不纳入文摘。
9.首句不得简单重复题名中已有的信息。
10.用过去时态叙述作者工作，用现在时态叙述作者结论。
11.文摘中的缩写名称在第一次出现时要有全称。
12.文摘中的特殊字符。主要指各种数学符号、数学公式、矩阵、数列、希腊字母、上下角标等。Ei对此专门有规定，希望在文摘中尽量少用特殊字符，因为它们的输入极为麻烦，而且极易出错，影响文摘本色的准确性和可读性，应尽量不用，改用文字表达或文字叙述。更复杂的表达式几乎难以输入，应设法取消。

以下列出两篇文章的摘要：

基于IGES文件输入的图形电磁计算方法

摘要: 在不同波段不同极化下，应用图形电磁计算（GRECO）法计算了某模型的高频雷达散射截面（RCS）.采用计算机硬件完成遮挡计算，通过五光源分两次照射获取模型表面法矢信息.在计算镜面散射时，利用两个Sinc函数的乘积消除物理光学计算中的奇异点，棱边边缘绕射用等效电磁流法计算.最终计算结果和试验结果吻合较好,表明这种方法估算目标RCS快捷有效，可以应用于工程分析.在目标造型端添加了识别读入IGES文件的端口后，解除了对模型造型格式的严格限制，扩大了其应用范围.

Graphical electromagnetic computing method research based on IGES files import

Abstract: The high frequency radar cross section (RCS) of a model was computed with the graphical electromagnetic computing (GRECO) method at different wave band and polarization. The shadowed and eclipsed surfaces were identified by using the visualization hardware, and the unit normal to surfaces were got with 5 light sources through 2 times of illumination. While computing the mirror-scattering RCS, 2 Sinc-functions were used to avoid singular points in physical optics (PO) results and method of equivalent currents (MEC) was used to compute the reflection of the edges. The agreement of the final computation results with the experimental data indicates this method could be used to estimate the model's RCS quickly and effectively at engineering analyses. Having added the interface that can identify and read initial graphics exchange specification (IGES) files, the limit to the type of the modeling files is released and the GRECO method's application range is extended.

反射器夹层面板精密成形原理

摘要:对高精度、大面积不可展双曲反射面的制造问题，提出了基于离散钉模、真空负压、蜂窝夹层、应力释放、回弹补偿的高精度反射面板成形原理；建立了四边自由面内多点约束的薄板大挠度弯曲解法及夹层板成形过程仿真模型，用于确定成形工艺参数；利用动力显式和静力隐式算法相结合的方法实现成形过程仿真；通过开缝和开槽方法释放面内压应力，确定了面板开缝和开槽方案；通过逆向修正离散模包络面，使其与成形模拟得到的夹层板型面误差最小，得到模具修正因子，补偿回弹误差.在此基础上开发了夹层板精密成形系统.该方法制造的面板型面精度达到25 μm以下，已成功地应用于多项大型紧缩场和毫米波天线的制造.

Principle of precision forming for sandwich panel of large antenna reflector

Abstract: To solve precision forming problem of the antenna panels with large non-developable double-curvature surface, the precision forming principle was proposed, based on “discrete nails die, vacuum press, honeycomb sandwich, stress release in-plane, and springback compensation”. The problem of rectangle thin plate with free edges and constrained at arbi

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