Results 231 to 240 of about 431,056 (283)

Curve Parametrization by Moments

IEEE Transactions on Pattern Analysis and Machine Intelligence, 2009
We present a method for deriving a parametric description of a conic section (quadratic curve) in an image from the moments of the image with respect to several specially-constructed kernel functions. In contrast to Hough-transform-type methods, the moment approach requires no large accumulator array.
Irina, Popovici, William Douglas, Withers   +1 more
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Non-parametric lactation curves

Animal Science, 1989
ABSTRACTLactation curves are fitted to data as a preliminary to estimating summary statistics. Two widely quoted curves are atbe-ct (Wood, 1967) and a(1 - e-bt) - ct (Cobby and Le Du, 1978), each of which has three parameters. Restriction to either of these curves imposes limitations on the fit to the data and can result in biased estimation of summary
D. A. Elston, C. A. Glasbey, D. R. Neilson   +2 more
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Degenerate parametric curves

Computer Aided Geometric Design, 1984
A degenerate parametric polynomial curve is defined as one that (a) does not have a one-to-one correspondence between points of the curve and points in the domain or (b) has a common factor in the numerator and denominator (for rational curves). Methods are developed to detect and remove such situations, i.e. by a suitable reparametrization.
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Numerically Parametrizing Curves

The College Mathematics Journal, 1998
(1998). Numerically Parametrizing Curves. The College Mathematics Journal: Vol. 29, No. 2, pp. 104-119.
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Fitting parametric disk curves

International Journal of Computer Mathematics, 1999
Methods for fitting parametric disk curves to a set of disks are developed.
Lin, Q, Rokne, JG
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Modular Parametrizations of Elliptic Curves

Canadian Mathematical Bulletin, 1985
AbstractMany — conjecturally all — elliptic curves E/ have a "modular parametrization," i.e. for some N there is a map φ from the modular curve X0(N) to E such that the pull-back of a holomorphic differential on E is a modular form (newform) f of weight 2 and level N.
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Algebraically rectifiable parametric curves

Computer Aided Geometric Design, 1993
A differentiable parametric curve \((x(t),y(t))\) is said to be a polynomial parametric one, if \(x(t)\), \(y(t)\) both are polynomials. In this paper sufficient and necessary conditions for the arc length \(s(t) = \int^ t_ 0 \sqrt{x'{}^ 2(\tau) + y'{}^ 2(\tau)} d\tau\) of a polynomial parametric curve to be an algebraic function of the parameter are ...
Sakkalis, Takis, Farouki, Rida T.
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Parametrizations and Plane Curves

2021
The chapter is devoted to the study of plane curves from the point of view of differential geometry. We focus our attention to classical curves and also on conics, and provide examples and other applications in architectural elements of the mathematical theory.
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Blending two parametric curves

Computer-Aided Design, 2009
Segments of two given curves can be blended to produce a segment of a new curve. Blending can provide a smooth transition from one curve to another and can give various degrees of smoothness at the endpoints of the blend, where the smoothness is measured analogously to parametric continuity C^(^n^) and geometric continuity G^(^n^). Blending can provide
D.S. Meek, D.J. Walton
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Reconsidering algorithms for real parametric curves

Applicable Algebra in Engineering, Communication and Computing, 1995
The authors study the applicability of known algorithms for computing complex parametrizations of curves to the case of real parametrizations. Several results hold over a real curve and its complexification. For example, a real curve has a real parametrization if and only if it has genus zero.
Alonso, Cesar, Gutierrez, Jaime, Recio, Tomas   +2 more
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