查询词典 surfaces

Applyingthe sufficient and necessary condition of biquadratic Bézier patch being non-negative,a method is presented to see whether two points are the closest points between twobiquadratic NURBS surfaces when the two points are respectively on the two surfaces. Based on the method, the surface split algorithm is improved while the surfaces arebiquadratic NURBS surfaces.

本文利用双二次 Bézier 曲面为非负的充要条件，提出了分别位于两张双二次 NURBS 曲面上的点是否为这两张曲面间距离最近的点的判别方法，并由此在双二次 NURBS 曲面的场合对计算最短距离的曲面分割法作了改进。

Nutlets 4, semiglobose-tetrahedral or subulate trigonous-tetrahedral, shiny, glabrous or pubescent, rarely tuberculate, adaxial 3 surfaces subequal in size or bottom smaller than 2 lateral surfaces, longitudinal vein at juncture of 2 lateral surfaces, sessile or with a short carpophore from corner of 3 adaxial surfaces, abaxial surfaces flattened or convex, acute or obtuse ribbed, rarely narrow winged; attachment scar at bottom of carpophore or at corner of 3 adaxial surfaces when sessile.

小坚果4，三棱四面体，发亮的半球形四面体或钻形，无毛或被短柔毛，具瘤，正面3 表面大小近等或者最后的小于2侧面的很少，在2侧面的接合的纵向脉，角落的3正面的在底部附件痕的果瓣柄或什么时候无梗。

The aerodynamics characteristic of the innovative control surfaces which are implemented on the flying wing aircraft with large aspect ratio were introduced, and elevon and split rudder were involved. And the control effects on three axis were analyzed basing on computetional fluid dynamics method. The concept of control volume was imported to introduce parameters-based method of control surfaces design. The control effect requirements of the control surfaces were also evaluated. The original design of certain aircraft's control surfaces was modified.

介绍了在该新布局飞机上采用的升降副翼和开裂式方向舵等新型操纵面的气动特点，并在计算空气动力学的基础上分析了其三轴控制效率，引进舵容量的概念提出了操纵面的参数化设计方法，基于飞机的可控性对各新型操纵面的操纵效率需求进行了评估，最终对某型飞机的操纵面初步设计进行了修正。

We proved that the minimal surfaces were isothermal parameter surfaces and harmonic surfaces. The symmetry and the self-intersection properties of the minimal surfaces were studied.

证明了该曲面既为等温参数曲面又为调和曲面，并研究了该曲面的对称性质与自交性质。

This device is characterised by that its beam-splitter unit is the above described one, the first focusing elements (24) are placed at two opposite sides as seen from the direction of the beam arriving to the semitransparent reflective surfaces of the optical beam-splitter unit (22) i.e. from the receiving direction (5) and the common optical axis (23) of the first focusing elements (24) is at right angles to the receiving direction; outside the first focusing elements (24) on both sides a mirror is placed in front of each eye, and the semitransparent reflective surfaces of these mirrors enclose an angle delta 45 DEG +-15 DEG with the above mentioned optical axis (23), and the intersection line of these reflective surfaces is parallel to the mirror crossing intersection line (4) of the semitransparent reflective surfaces.

该双目图像显示装置的特征是其光学分束器单元是所述的单元，从到达光学分束器单元(22)的半透明反射面的光束方向看，即从接收方向(5)看，第一调焦元件(24)放置在相对的两侧，并且第一调焦元件(24)的共同光轴(23)垂直于接收方向；在位于两侧的第一调焦元件(24)的外面反射镜放置在每一只眼睛的前面，并且这些反射镜的半透明反射面与所述共同的光轴(23)围成夹角δ45°±15°，并且这些反射面的交线平行于半透明反射面的交叉反射镜交线(4)。

By the definition of Darboux type vector and rectifying Darboux type vector ,we constructed the rectifying type developable surfaces and Darboux type developable surfaces and tangential Darboux type developable surfaces ,and study these three developable surfaces relationship with Minkowski slant helices and Minkowski conical geodesic curves. Bying applying the singularity theoerical knowledge, We give a classification of special developable surfaces under the condition of the existence of such a special curve as geodesic.

通过定义三维Minkowski空间中的达布型向量以及修正达布型向量，构造出三维Minkowski空间中的三类可展曲面，即修正型可展曲面、达布型可展曲面和切达布型可展曲面，研究Minkowski斜螺线和Minkowski锥面测地线这两种特殊曲线和这些曲面的关系，并研究Minkowski斜螺线和Minkowski锥面测地线作为这些曲面的测地线的条件下，运用奇点理论的知识，对这三种可展曲面进行奇点分类。

Two above methods are generalized to tensor product Bézier surfaces and triangular Bézier surfaces, we give two approaches of degree reduction for tensor product Bézier surfaces, each of which reduces a given degree n×m tensor product Bézier surface to a n〓×m〓 one, and two methods of degree reduction for triangular Bézier surfaces, which reduce a given degree n triangular Bézier surface to a degree m one. The explicit formulas of control points for reduced tensor product and triangular Bézier surfaces are obtained respectively.

张量积Bézier曲面的两种降阶方法均可把n×m阶张量积Bézier曲面一次降阶为n〓×m〓阶张量积Bézier曲面；三角Bézier曲面的两种降阶方法均可把n阶三角Bézier曲面一次降阶为m阶三角Bézier曲面，并给出降阶张量积Bézier曲面和降阶三角Bézier曲面控制顶点的显示表示式。

By means of moving frame, some properties of ruled surfaces are obtained, including the surfaces being minimal, totally geodesic, totally developableand totally umbilical. Some equivalent conditions in which the ruled surfaces are totally developable are obtained. It is abtained that (k+1)-dimensional ruled surfaces are totally geodesic if and only if they are minimal and totally developable.

利用活动标架法研究了直纹面的一些性质，包括极小性，全可展性，全测地性和全脐性，给出了直纹面是全可展性的一组充要条件，同时得到，R(上标 n+1 下标 v)中的k+1维直纹面M是全测地的充要条件是它是极小的且全可展的。

The invention concerns an artificial block comprising a central core (1) having first (11) and second (12) opposite surfaces each provided with an anvil-shaped side leg (21, 22) with a table (21A, 22A), two sloping sides (21E, 21G; 22E, 22G) and two side surfaces (21B, 21C; 22B, 22C), the tables of said side legs being arranged parallel to said first and second opposite surfaces of the core, the inclined sides of said side legs resting on third (13) and fourth (14) exposed opposite surfaces of said core, said core having fifth (15) and sixth (16) surfaces each provided with side legs and front legs shaped like a truncated pyramid with four side surfaces and one front surface (33) parallel to said fifth and sixth surfaces of the core and to the side surfaces of the side legs.

一种保护层块料，包括一个中心核体(1)，有相对的第一面(11)及第二面(12)，每一面上各有一个砧状侧凸起(21，22)，这两个侧凸起各有一个台面(21A；22A)、两个斜面(21E，21G；22E，22G)和两个侧面(21B，21C；22B，22C)，所述台面相互平行，而且平行于所述中心核体的相对的第一面及第二面，所述侧凸起的斜面支撑于所述核体的相对的可见的第三(13)和第四面(14)。所述核体还有相对的第五(15)和第六面(16)，其上各有一个锥台状的前凸起，该前凸起有四个侧面和一个前表面(33)，该前表面平行于所述核体的第五和第六面，还平行于侧凸起的侧面。

The silica surfaces polished with ion beam of 400ev energy and 100mA density in 35°incident angle for 2hrs was found to have a roughness less than 0.5nm . The SFM was also used to measure the surfaces to be bonded by SAB method and the deformations of the surfaces during contact each other. The micro roughness of the surfaces was found to produce great effect on the SAB strength. The rougher the surfaces are, the weaker the bonding forms.

本文首先将原子力显微镜应用于一种新的超光滑表面离子束抛光的工艺研究，搞清了表面纳米级微观形貌与离子束抛光参数之间的关系，在离子能量为400V、束流密度为100mA和入射角为40°时，经过两个小时以上的抛光，硅（111）表面微观形貌在1μm×1μm的范围内从抛光前的5nm下降到0.4nm。

This is not an ordinary box, which is used as a background picture of the dialog box, very pretty.

详细说明：这可不是一个一般的对话框，它是用图片作为背景的对话框，非常好看。

Conceal me what I am,and be my aid for such disguise as haply shall become the form of my intent.

遮掩我的身份，帮助我，我的面具将成为我的目的。