On a projective deformation of ruled surfaces
نویسندگان
چکیده
منابع مشابه
On Higher Syzygies of Ruled Surfaces
We study higher syzygies of a ruled surface X over a curve of genus g with the numerical invariant e. Let L ∈ PicX be a line bundle in the numerical class of aC0 + bf . We prove that for 0 ≤ e ≤ g − 2, L satisfies Property Np if a ≥ p + 2 and b − ae ≥ 3g − e + p and for e ≥ g − 1, L satisfies Property Np if a ≥ p + 2 and b − ae ≥ 2g + 1 + p. By using these facts, we obtain Mukai type results. F...
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In this article we we continue the study of property Np of irrational ruled surfaces begun in [12]. Let X be a ruled surface over a curve of genus g ≥ 1 with a minimal section C0 and the numerical invariant e. When X is an elliptic ruled surface with e = −1, there is an elliptic curve E ⊂ X such that E ≡ 2C0 − f . And we prove that if L ∈ PicX is in the numerical class of aC0 + bf and satisfies...
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Given a surface or scattered data points from a surface in 3-space, we show how to approximate the given data by a ruled surface in tensor product B-spline representation. This leads us to a general framework for approximation in line space by local mappings from the Klein quadric to Euclidean 4-space. The presented algorithm for approximation by ruled surfaces possesses applications in archite...
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In this study, we give the relationships between the conical curvatures of ruled surfaces generated by the unit vectors of the ruling, central normal and central tangent of a ruled surface in the Euclidean 3-space E^3. We obtain differential equations characterizing slant ruled surfaces and if the reference ruled surface is a slant ruled surface, we give the conditions for the surfaces generate...
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ژورنال
عنوان ژورنال: Czechoslovak Mathematical Journal
سال: 1955
ISSN: 0011-4642,1572-9141
DOI: 10.21136/cmj.1955.100151