Cohomology of Crystalline Smooth Sheaves

We define and study a candidate for 'arithmetic' cohomology theory with values in crystalline p-adic smooth sheaves. We show that it injects into arithmetic étale cohomology and prove a duality result.     

Some new results on planar harmonic mappings

This survey paper contains some new results on the Landau theorem, Bloch theorem and Schwarz-Pick lemma for planar harmonic mappings.     

On the worst conditional expectation

We study continuous coherent risk measures on L^p, in particular, the worst conditional expectations. We show some representation theorems for them, extending the results of Artzner, Delbaen, Eber, Heath, and Kusuoka.     

局部凸空间中的Drop定理和Phelps引理以及Ekeland变分原理

本文将Drop定理,Phelps引理,Ekeland变分原理和基于Isac的Pareto有效性定理推广到局部完备的局部凸Hausdorff空间,而且证明了它们彼此是等价的．     

集值映射下一类广义向量均衡问题解的存在性

研究集值映射下一类广义向量均衡问题，通过建立一种新的弱半连续及类凸的概念，引进集值映射下推广的Minty引理，利用KKM定理讨论了广义向量均衡问题解的存在性。     

Asymptotic Dual Conditions Characterizing Optimality for Infinite Convex Programs

Characterizations of optimality are presented for infinite-dimensional convex programming problems, where the number of constraints is not restricted to be finite and where no constraint qualification is assumed. The optimality conditions are given in asymptotic forms using subdifferentials and €-subdifferentials. They are obtained by employing a version of the Farkas lemma for systems involving convex functions. An extension of the results to problems with a semiconvex objective function is also given.     

A Theorem of the Alternative in Banach Lattices

We consider a linear sytem in a Banach lattice and provide a simple theorem of the alternative (or Farkas lemma) without the usual closure condition.

     

Arithmetic cusp shapes are dense

In this article we verify an orbifold version of a conjecture of Nimershiem from 1998. Namely, for every flat n-manifold M, we show that the set of similarity classes of flat metrics on M which occur as a cusp cross-section of a hyperbolic (n + 1)-orbifold is dense in the space of similarity classes of flat metrics on M. The set used for density is precisely the set of those classes which arise in arithmetic orbifolds.      

Robust Analysis and Synthesis for the Nonexistence of Periodic Solutions in a Class of Nonlinear Systems

This paper considers the nonexistence of periodic solutions in a class of nonlinear uncertain systems. Based on the generalized Kalman–Yakubovich–Popov (GKYP) lemma, linear matrix inequalities (LMIs) characterizations are derived to guarantee the nonexistence of periodic solutions in a certain frequency range. The new LMI conditions do not involve any product of the Lyapunov matrix and the system matrices. Based on the results, a dynamic output feedback controller is designed to ensure the nonexistence of periodic solutions in such systems. A concrete application to the Chua circuit shows the applicability and validity of the proposed approach. This work was supported by the National Science Foundation of China under Grants 60404007 and 60334030.