期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
A Symbolic-Numeric Approach for Parametrizing Ruled Surfaces 被引量:1
1
作者 PÉREZ-DÍAZ Sonia SHEN Li-Yong 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2020年第3期799-820,共22页
This paper presents symbolic algorithms to determine whether a given surface(implicitly or parametrically defined)is a rational ruled surface and find a proper parametrization of the ruled surface.However,in practical... This paper presents symbolic algorithms to determine whether a given surface(implicitly or parametrically defined)is a rational ruled surface and find a proper parametrization of the ruled surface.However,in practical applications,one has to deal with numerical objects that are given approximately,probably because they proceed from an exact data that has been perturbed under some previous measuring process or manipulation.For these numerical objects,the authors adapt the symbolic algorithms presented by means of the use of numerical techniques.The authors develop numeric algorithms that allow to determine ruled surfaces"close"to an input(not necessarily ruled)surface,and the distance between the input and the output surface is computed. 展开更多
关键词 Implicit representation numeric algorithm ruled surface standard parametrization
原文传递
On the Base Point Locus of Surface Parametrizations:Formulas and Consequences
2
作者 David A.Cox Sonia Pérez-Díaz J.Rafael Sendra 《Communications in Mathematics and Statistics》 SCIE 2022年第4期757-783,共27页
This paper shows that the multiplicity of the base point locus of a projective rational surface parametrization can be expressed as the degree of the content of a univariate resultant.As a consequence,we get a new pro... This paper shows that the multiplicity of the base point locus of a projective rational surface parametrization can be expressed as the degree of the content of a univariate resultant.As a consequence,we get a new proof of the degree formula relating the degree of the surface,the degree of the parametrization,the base point multiplicity and the degree of the rational map induced by the parametrization.In addition,we extend both formulas to the case of dominant rational maps of the projective plane and describe how the base point loci of a parametrization and its reparametrizations are related.As an application of these results,we explore how the degree of a surface reparametrization is affected by the presence of base points. 展开更多
关键词 Base point Hilbert-Samuel multiplicity Surface parametrization Reparametrization Parametrization degree Surface degree
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部