QQ(R) (abbreviated as Q) is the space of unordered Q points in R introduced by Almgren [AF]. In this paper, we first show that the space Q with metric G is non-negatively curved in the sense of Alexandrov. We also discuss some issues like metric tangent cone and exponential map. In the second part, we define the signature of points in Q, give a decomposition of this metric space according to th...

Constraint qualifications (CQ) are assumptions on the algebraic description of the feasible set of an optimization problem that ensure that the KKT conditions hold at any local minimum. In this work we show that constraint qualifications based on the notion of constant rank can be understood as assumptions that ensure that the polar of the linear approximation of the tangent cone, generated by ...

This paper presents an approach for designing a developable surface possessing a given curve as the geodesic of it. We analyze the necessary and sufficient conditions when the resulting developable surface is a cylinder, cone or tangent surface. Also, we solve the problem of requiring the surfaces of revolution which are developable surfaces. Finally, we illustrate the convenience and efficienc...

We prove that a Lebesgue measure-preserving linked-twist map defined in the plane is metrically isomorphic to a Bernoulli shift (and thus strongly mixing). This is the first such result for an explicitly defined linked-twist map on a manifold other than the two-torus. Our work builds on that of Wojtkowski (1980) who established an ergodic partition for this example using an invariant cone-field...

A Weyl structure on a compact conformal manifold is not complete in general. If, however, the life-time of incomplete geodesics can be controlled on compact subsets of the tangent bundle, the Weyl connection is called tame. We prove that every closed, non-exact, tame Weyl structure on a compact conformal manifold is either flat, or has irreducible holonomy, generalizing an analogous statement f...

In this paper, we introduce the notion of “extension” of a toric variety and study its fundamental properties. This gives rise to infinitely many toric varieties with a special property, such as being set theoretic complete intersection or arithmetically Cohen-Macaulay (Gorenstein) and having a Cohen-Macaulay tangent cone or a local ring with non-decreasing Hilbert function, from just one singl...

This paper investigated the rotation minimizing frames that are related to space curves and sweeping surfaces traced by these in three-dimensional Lie group. Then, sufficient necessary conditions for surface be a developable ruled were obtained. In particular, we mostly focused on study of resulting is cylinder, cone, or tangent surface. Meanwhile, support results paper, some illustrative examp...

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