On Pappus-Type Theorems on the Volume in Space Forms

Let c be a curve in a n-dimensional space form M ⁿ , let P _t bea totally geodesic hypersurface of M ⁿ orthogonal to c at c(t),and let D₀ be a domain in P ₀. If D is thedomain in M ⁿ obtained by a motion of D₀ alongc and D _t is the domain in P _t obtained by the motion ofD₀ from 0 to t, we show that the n-volume ofD depends only on the length of the curve c, its first curvature, themodified (n – 1)-volume of D₀ and the moment of D _t with respect to the totally geodesic hypersurface of P _t orthogonal to the normal vector f ₂(t) of c. As a consequence, if c(0) is the center of mass of D₀, then the n-volume ofD is the product of the modified (n – 1)-volume of D₀ and the length of c. We get an analogous theorem for ahypersurface of M ⁿ obtained by parallel motion of ahypersurface of P ₀ along c.     

非Lipschitz条件下严格伪压缩映射不动点的逼近

Abstract. Without the Lipschitz assumption and boundedness of K in arbitrary Banach spaces,the Ishikawa iteration     

关于陈微分式的一个注记

在陈省身先生关于高斯—波涅公式的著名证明中有一个关键等式，本文对这一等式给出一个稍稍改动的证明，相信更清楚地贴近陈的想法。     

新疆柯柯亚水库生态景观规划理念与实践

水库生态景观包括库区自然景观系统与枢纽人工景观系统．其有机构成方式属于景观生态学的范畴．本文从景观学原则出发．在对新疆柯柯亚水库景观特征分析的基础上提出了相应的规划原则和设计理念，对该水库旅游景点规划设计提供了决策依据．对其它水库的生态建设也有指导意义．     

Approximate cores of replica games and economies: Part II: Set-up costs and firm formation in coalition production economies

A model of a coalition production economy allowing set-up costs, indivisibilities,and nonconvexities is developed. It is shown that for all sufficiently large replications, approximate cores of the economy are nonempty.     

Exact solution of a simple finite infinite source interaction model

Networks of queues with finite and infinite source customers have been used to study the interaction between the batch jobs and interactive jobs in computer systems. Earlier Kaufman ([1], PP-345-348) developed accurate approximations for a simple nonproduct form network of this type. In this paper we offer exact solutions for the same model with one finite source customer. We study both FIFO and LIFO disciplines at the contention node. The results are derived for the case where the finite source think time and service time distributions are generalized hyperexponential.     

The simple geometry of perfect information games

Perfect information games have a particularly simple structure of equilibria in the associated normal form. For generic such games each of the finitely many connected components of Nash equilibria is contractible. For every perfect information game there is a unique connected and contractible component of subgame perfect equilibria. Finally, the graph of the subgame perfect equilibrium correspondence, after a very mild deformation, looks like the space of perfect information extensive form games.     

Local densities of 2-adic quadratic forms

In this paper, we give an explicit from formula for the local density number of representing a two by two 2-integral matrix T by a quadratic 2-integral lattice L over . The non-dyadic case was dealt in a previous paper. The special case when L is a (maximal) lattice in the space of trace zero elements in a quaternion algebra over yields a clean and interesting formula, which matches up perfectly with the non-dyadic case in terms of the Gross-Keating invariants. This work is used to compare the central derivative of a genus two Eisenstein series with certain generating function of arithmetic 0-cycles on certain Shimura curve, in a joint work with Kudla and Rapoport.