边界

On the basis of B-Rep of CAD data and ACIS library,a technology of surface filling based on loop feature handling and outlines smoothing is presented in the paper,filling for the surface with complex concave edges is also studied in the paper.

以CAD数据的边界表示法和ACIS几何开发库为基础，提出了基于环特征处理和外边界光顺的曲面填充技术，对含有复杂凹缘的汽车覆盖件曲面填充进行了研究。

The distribution of induced current and the acoustic pressure inside the spheres with different conductivity were presented.

仿真结果表明，感应电流密度在中心位置处为零，在电导率边界处变化较大；声压分布在中心位置处为零，在边界处变化较大。

The Frechet derivative of the cost function is determined via the solution of an adjoint partial differential equation, and the boundary shape is then modified in a direction of descent. This process is repeated until an optimum solution is approached. The advantage is that the cost function variation is independent of the flow field variation, with the result that the gradient of cost function with respect to arbitrary number of design variables can be determined without the need for additional flow-field evaluations. So each design cycle requires the numerical solution of both the flow and the adjoint equations leading to a computational cost roughly equal to the cost of two flow solutions.

虽然他们的研究成果大多数都可以在公开性文献上看到，但是其中一些具体的细节问题的处理方法却没有透露，比如：伴随方程如何离散求解才能减小最终梯度计算中的误差，使得设计过程有效地进行；伴随方程与流动方程的边界条件是不同的，如何合理地处理伴随方程的边界条件，才能推动设计过程朝着设计目标而发展；在减阻问题中目标函数如何定义，求解梯度的具体数学公式如何推导，如何通过数值方法来实现它们等。

The effects of magnitude and distribution of the electromagnetic force on the flow around the aerofoil were investigated. The results show that the electromagnetic force with large magnitude and concentrated distribution on the surface of aerofoil is advantageous to eliminate vortex structures and boundary separation, and therefore to increase the lift-drag ratio.

同时对不同电磁力大小和分布影响翼型表面边界层流动的规律进行了探讨，其结果表明，较大的电磁力和更加集中于翼型表面的电磁力分布可以很好地消除涡结构，抑制边界层分离进而达到提高升阻比的效果。

A stress function involving several unknown co efficients was constructed in the solution process, and the stress and displacement expressions were obtained through traditional Airy stress function methodology. After the fixed end boundary condition was treated with two methods, the unknown coefficients in stress function were determined with stress and displacement boundary conditions, and the analytical solutions were achieved.

在求解过程中，构造了一个含待定系数的应力函数，通过Airy应力函数解法，给出了应力和位移的表达式，对固支端边界条件采用两种处理办法，利用应力和位移边界条件，确定应力函数中的待定系数，得到了应力和位移的解析解结果。

The technique of boundary-fitted coordinate system is used to overcome the difficulties resulting from the complicated shapes of natural river boundaries;the method of alternating direction implicit finite difference scheme is used to solve the partial differential equations in the transformed plane;and the technique of moving boundary is used to deal with the river bed exposed to water surface.

用适体坐标技术克服天然河道复杂的几何边界给有限差分法所带来的困难；用交替方向隐式有限差分格式求解变换平面上的偏微分方程；用动边界技术处理河床的淹露。

This thesis contributed to the comprehensive study of the Finite-Difference Time-Domain method and its application to the numerical computation of radiated electromagnetic fields in switched mode power supplies. The work includes mainly three parts: the study on the performance of PML absorbing boundary condition applied to pseudo low frequency electromagnetic problems; the validation of the FDTD method with PML absorbing boundary conditions and the corresponding computer software based on the numerical study of the electromagnetic field of an electric dipole antenna, and its application to the numerical computation of radiated electromagnetic fields in switched mode power supplies; the development of an improved alternating direction implicit finite-difference time-domain method.

在综合前人工作基础上，本文对时域有限差分法及其在开关电源辐射电磁场数值计算中的应用进行了系统的分析和研究，其核心内容包括：伪低频电磁场数值计算中PML吸收边界条件性能的研究；基于基准问题—电偶极子天线三维辐射电磁场，验证了本文构造的基于PML吸收边界条件的三维FDTD法及其计算软件，并应用于高频开关电源辐射电磁场的数值分析；提出了一种改进的交替方向隐格式时域有限差分法。

The anisotropic diffusion not only can keep the edge of the image but also can enhance the edge.

各向异性扩散滤波不仅能很好地保持目标的边界而且对边界具有增强的作用。

The exchange of substances between deposited sediments and overlying water must also pass through the DBL. In this study, two series of flume experiments with and without wind blowing conditions were conducted to study the salt release process from sandy sediments in a polder reservoir. The thickness of DBL was directly measured. The experimental salt fluxes through the DBL under the two wind conditions were inter-compared and compared with the estimations using the Fick's first law in an effort to explore the role of DBL in contact inhibition of salt release.

通过无风和有风条件下两组沉积物盐分释放实验，研究海湾水库砂质沉积物－水界面扩散边界层的形成情况，并通过水动力扰动下穿过扩散边界层的实测盐分通量与Fick第一定律理论计算通量的比较，以及扰动与无扰动时通量的比较，探讨扩散边界层对沉积物盐分释放的影响。

The transmission of heat differential equation for the heat conduction process of thermoelectric module was derived And the solution with the first kind boundary conditions under the influence of Thomson effect and the solution with the third kind boundary conditions without the influence of Thomson effect was obtained.

在假设热电制冷的热端温度固定的条件下，得出热电制冷器在不同工况下的最佳工作参数并进一步求得在三类边界条件下的最佳工作参数；导出了电偶臂在电与热的偶合作用下传热微分方程，并对其进行解析求解：在考虑汤姆逊效应的影响下得出一类跟三类边界条件下传热方程的解析解，在忽略汤姆逊效应的影响下得出二类跟三类相的边界条件下传热方程的解析解。

And Pharaoh spoke to Joseph, saying, Your father and your brothers have come to you.

47：5 法老对约瑟说，你父亲和你弟兄们到你这里来了。

Additionally, the approximate flattening of surface strip using lines linking midpoints on perpendicular lines between geodesic curves and the unconditional extreme value method are discussed.

提出了用测地线方程、曲面上两点间短程线来计算膜结构曲面测地线的方法，同时，采用测地线间垂线的中点连线和用无约束极值法进行空间条状曲面近似展开的分析。