二次曲面

A method is proposed to calculate these features from a general quadric surface fitted at each point.

本文提出了一种从散乱坐标点拟合一般二次曲面，然后估计曲率张量的方法。

Chapter 3 introduces a new fingerprint segmentation method based on quadric surface model, which is the main innovation of this article.

第一章绪论，主要介绍了指纹识别技术的概况及其存在的技术难点；做为开展研究工作的基础，第二章研究并实现了基于块图像的指纹分割方法；第三章详细介绍了本文的主要创新之处——提出并实现使用二次曲面模型进行指纹图像分割的方法；第四章是指纹匹配算法研究，对一种现有的指纹匹配算法进行了一定改进；第五章为总结和探讨。

A fitting method that simultaneously fits specific quadric forms to both surface and contour data at object limbs or creases is presented.

本文所提供的方法，乃是经由将线条及表面的资料，同时调适，使得以匹配二次曲面形式的一种技巧。

The results show that the proposed method provides accurate highresolution segmentation results, which has only 0.80% misclassified pixels, while the quadric surface classifier has 0.97% misclassified pixels.

实验结果表明新方法提供了更精确的分割结果，仅有0.80%的像素分割错误，而二次曲面分割法的错误率为0.97%。

It is shown that from the comparison among the results with the calculation methods by surface fitting, quadric surface fitting, and other neural network methods, the accuracy by using the standardization of BP neural network algorithm for elevation fitting is more reliable and stable.

将该方法得到的计算结果与平面拟合、二次曲面拟合及其他神经网络方法计算的结果进行对比得出：标准化动量BP神经网络算法求解高程，精度可靠且稳定。

Classifying and computing a QSIC (quadric surface intersection curve) are important operations in computing the boundary representation of a solid in solid modeling system, and also are applied in other geometric processing.

对两二次曲面交线(QSIC-Quadric SurfaceIntersection Curve)的拓扑分类和计算是立体造型系统计算三维物体边界表示的一个非常重要的操作，同时还可应用在其它的几何处理算法中。

Random sampling consensus algorithm ; Triangular mesh ; Quadric surface extraction

随机抽样一致性算法；三角网格；二次曲面提取

It is very helpful to instinctively understand the morphology of the QSIC such a quadric pencil has.

它们对直观上理解两二次曲面交线的拓扑形态有非常重要的意义。

By learning this course, students should proficiently use algebraic methods to solve geometric problems and practical problems, and proficiently grasp the basic ideas and methods of vector algebra and geometric properties of spatial line, plane and quadratic surface.

通过本课程的学习使学生熟练掌握运用代数方法解决几何问题并应用于实际问题之中，并熟练掌握向量代数的基本思想和方法，同时使学生熟练掌握空间的直线、平面和二次曲面及其各种几何性质。

This kind of method is workable.

这种方法是简化二次曲面的一种新方法。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。