这就会变成…，如果俯视这个抛物面，所看到的就是单位圆盘，这就应该是单位圆上的二重积分了。

That is just going to be, if you look at this paraboloid from above, all you will see is the unit disk so it will be a double integral of the unit disk.

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水星二重成像系统(MDIS)：在近红外波段上拍摄金星的夜面，对接近以及离去半球的彩色及高解析度单色图像拼接。

Mercury Dual Imaging System (MDIS) : Images of the night side of Venus in near-infrared wavelengths; color and high-resolution monochrome mosaics of both the approaching and departing hemispheres.

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提出了二重八面体变几何桁架机器人工作空间的边界曲面分析方法。

Boundary surface analysis method for workspace of double-octahedron variable geometry truss robotic manipulators(VGTRM) is proposed in this paper.

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