查询词典 projection gradient method

By taking advantage of a corollary of the Desargues theorem and the corresponging extension of Desarguesian configuration, the concept of stereohomology has been defined in projective geometry and presented based on homogeneous coordinates. Consequently, a series of geometrical transformations, such as central projection, parallel projection, centrosymmetry, translation transformation, reflection, rotation transformation, which can be contained in it or derived from it have also been analytically defined.

利用Desargues定理的一个推论和引申的Desargues图形，给出"空间透射"在射影几何意义下基于齐次坐标表象的解析定义，从而解析定义了可蕴涵其中的中心投影、平行投影、中心对称、平移、反射等几何变换以及可由此衍生出的旋转变换。

As to the remaining parameters, two methods are developed: first, accepting that the projection function complies with a circular function within at least a part of a given field of view, constrained by the obtained object-to-image radial mapping and a constant focal length, the best-fitting point of the optical origin is tested along the optical axis; secondly, referring to the postulation of the exclusively bilateral mapping between an imaged point and its scenic sight ray, a measuring technique is developed to survey the world coordinates which will fabricate a projecting path to the imaged points located on the imageable region of the image plane in order to directly model the projection geometries involved.

而针对其余参数本文提出两种解题方法：其一是根据『在「部分视野角范围」内，鱼眼相机的投射模型符合一典型的「圆形函数」』以标靶实体与其影像尺寸为限制条件，测试光学轴上的最佳视觉参考点、鉴定最适当的投射模型、焦距、及有效的视野角度范围。其二是根据『一视野线排他性地与对应「呈影点」一一映射』参考一呈影点来搜寻空间中对应视野线的绝对座标后，据以演绎相机内部影像形成的模型。

This paper investigates the converse theorem of rectangular projection theorem in descriptive geometry,and furthermore supplements and confirms another converse theorem,If the projection of two lines intersecting vertically fo rms a rectangle on a certain projecting plane,at least one line of the two lines is parallel to the projecting plane.

通过对《画法几何学》中直角投影定理的逆定理的研究，得出："若垂直相交的两直线在某一投影面上投影成直角，则该两直线至少有一条直线平行于该投影面"的推论。

For solving problem (1), this dissertation first presents a sufficient and necessary condition by dealing with inequalities using projection operator in convex analysis, and then proposes a kind of new neural network model based on the constraint domain:〓(2) Where P is a projection operator on Q.

本文利用凸分析中的投影算子处理不等式约束，首先给出二次规划问题(1)解存在的充分和必要条件，据于此提出一种新的基于约束区域神经网络模型〓(2)来进行求解，其中P为Q上的投影算子。

In this article, we define a projection from a segment or a polygon to a convex solid and discuss the relationship between the projection and the pattern.

论文一开始先介绍空间中物件对正多面体投影的定义，在此定义下，我们将讨论在正多面体上投影与切割的关系。

Therefore, the primary purpose of the present study is to construct the projection methods in higher order accuracy. Furthermore, the proposed projection methods will be applied to nonstaggered grids, curvilinear coordinates, and moving mesh cases.

因此，本文从提高数值方法计算精度入手，构造了高阶时间精度的投影方法，并将投影方法推广到非交错网格和一般坐标系及动网格中。

Work in this paper focuses on the data mining from chromatographic retention index data. A retention index database that contains about 50000 records of retention index is firstly established. Projection pursuit technique is then utilized to do data mining upon the data in order to find out some valuable information about the relationship between the retention indices and structural descriptors. A novel algorithm for projection pursuit is developed in this work. Samples of alkane, alkene and cycloalkane are investigated.

中文题名化学数据挖掘新算法和定量构性关系基础研究副题名外文题名 New methodology in chemical data mining and foundational research on QSPR 论文作者杜一平导师梁逸曾学科专业分析化学研究领域\研究方向化学计量学学位级别博士学位授予单位湖南大学学位授予日期2002 论文页码总数115页关键词定量构性关系化学计量学数据挖掘馆藏号BSLW /2003 /O6 /2 化学数据挖掘正逐渐引起化学家们的关注。

Using planar graph to express the three-dimensional objects, or a projection map to express the three-dimensional objects, must be consistent with the projection theory of descriptive geometry.

用平面图形来表达三维立体实物，或用一个投影图来表达三维立体实物，必须符合画法几何的投影理论要求。

Study results indicate that the horizontal projection length of diagonal cracks cannot be predicted accurately when considering shear span ratio and strength ratio of longitudinal steels to stirrups separately. However the horizontal projection length can be well predicted through integrating these two influence factors due to their well representation of the entire process of diagonal cracks' occurring and development.

分析结果表明，单独考虑剪跨比和纵筋－箍筋强度比都不能很好地预测斜裂缝水平投影长度，而将两者结合能够较好地反应斜裂缝出现和发展的全过程，从而准确地计算斜裂缝水平投影长度。

In order to reduce distortions of map projection, a new map projection according to the normal of ellipsoid surface is proposed in this paper.

为更大幅度地减小地图投影变形，提出了按椭球面法线投影的一种新的地图投影方法。

He has to relate with three women in the movie, and yet remain implicitly faithful to the unseen Lucinda.

让克劳德布里亚里成功地饰演试验了一个难度很大的角色：和三个女人打交道，但还要底下对观众未曾谋面的卢馨达保持忠诚。

The experiment was conducted to study effects of inulin on the growth performance, indices of immune organs and serum immunoglobulin of laying chicklings as well as the performance of inulin which replaced the antibiotics in diets by adding 0.2%, 0.4% and 0.8% of inulin, respectively.

试验旨在通过在蛋用雏鸡日粮中添加0.2%、0.4%和0.8%的菊粉，研究菊粉对蛋雏鸡生长性能、免疫器官指数和血清免疫球蛋白的影响，以及菊粉替代抗生素对蛋雏鸡的应用效果。