Results 191 to 200 of about 351,850 (226)

On the Graded Ring of Theta-Constants

American Journal of Mathematics, 1964
Introduction. Let g be a positive integer and let T be a complex symmetric matrix of degree g with a positive-definite imaginary part. The set of such matrices forms a convex open subset of the 1 * g (g + 1) -dimensional complex vector space and (as a complex manifold) it is called the Siegel upper-half plane of degree (or "genus") g.
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Erdős–Burgess constant in commutative rings

Archiv der Mathematik, 2021
Let $$\mathcal {S}$$ be a nonempty semigroup endowed with a binary associative operation $$*$$ . An element e of
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The sharp constant in the ring lemma

Complex Variables, Theory and Application: An International Journal, 1997
In his paper [2] Lowell J. Hansen found a (nonlinear) recurrence formula for the (sharp constant appearing in the “Ring Lemma” of Rodin and Sullivan [3]. In the following we improve Hansen's result and replace his recurrence relation by a linear recurrence formula leading to a closed formula for the Ring Lemma constant.
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Practical Constant-Size Ring Signature

Journal of Computer Science and Technology, 2018
Bitcoin has gained its popularity for almost 10 years as a “secure and anonymous digital currency”. However, according to several recent researches, we know that it can only provide pseudonymity rather than real anonymity, and privacy has been one of the main concerns in the system similar to Bitcoin. Ring signature is a good method for those users who
Zhou-Jun Ma, Zhou-Jun Ma, Yun-Lei Zhao, Yun-Lei Zhao, Meng-Jun Qin, Meng-Jun Qin   +5 more
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Shirshov finiteness over rings of constants

Algebra and Logic, 1997
The author studies rings of constants for restricted differential Lie algebras acting on prime rings and having nontrivial quasi-Frobenius inner part. It is shown that, under this restriction, Shirshov's local finiteness correspondence exists between a given prime ring \(R\) and the ring of constants \(R^L\).
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Constant Volume Ring Shear Apparatus

Geotechnical Testing Journal, 1996
Abstract The paper describes a constant volume ring shear apparatus that allows the measurement of the undrained peak and residual shear strengths of cohesive soils. The undrained peak and residual strengths are applicable to seismic stability evaluations of slopes comprised of or founded on cohesive soil.
Timothy D. Stark, Ivan Contreras
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The instability of the thin vortex ring of constant vorticity

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences, 1977
A theoretical investigation of the instability of a vortex ring to short azimuthal bending waves is presented. The theory considers only the stability of a thin vortex ring with a core of constant vorticity (constant /r) in an ideal fluid. Both the mean flow and the disturbance flow are found as an asymptotic solution in e =a/R, the ratio of core ...
Chon-Yin Tsai, Sheila E. Widnall
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SHUFFLE-RING: A NEW CONSTANT-DEGREE NETWORK

International Journal of Foundations of Computer Science, 1998
The hypercube as a parallel interconnection network has been of academic and engineering concern for tens of year due to its many merits. However, its increasing node degree is an obvious weakness. Some networks such as the cube-connected cycles (CCC) and the de Bruijn network have been proposed to overcome the increasing degree of the hypercube.
Francis C. M. Lau, Guihai Chen
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Graded Rings of Theta Constants

1972
Let z → θm(τ, z) denote the familiar theta function on Cg;; we recall that m = (m′m″) is in R2g and τ in 𝔖g. If m is in Q2g, we call θm(τ, 0) a theta constant. Since in this chapter we shall mainly consider theta constants rather than theta functions, we make an agreement that θm means the function τ → θm(τ, 0) on 𝔖g; accordingly, we shall write θm(τ ...
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Remarks on rings of constants of derivations II

Communications in Algebra, 1992
Let k be a field of characteristic p>0 and D≠0 a family of k-derivations of k[x,y]. It is proved in [1] that k[x,y]D, the ring of constants with respect to D, can be generated, as a k[x p,y p]-algebra, by p - 1 elements. In this note we prove that p - 1 is the sharp upper bound of numbers of generators.
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