Optimal control of time delay parabolic systems

Various optimal control problems for linear parabolic systems with multiple constant time delays are considered. Necessary and sufficient conditions of optimality are derived for the Neumann problem. The optimal control is obtained in the feedback formMaking use of the results of Schwartz's, the representation of the optimal feedback control is given. A simple example of application is also provided     

Lower subdifferentiability in minimax fractional programming *

Minimax fractional programming problems are analyzed from the view- point of lower subdifferentiability, obtaining Kuhn-Tucker type optimality conditions. Multiobjective optimization problems with fractional objectives are also studied.     

Vector subdifferentials via recession mappings ∗ ∗this research was supported by grants from M.U.R.S.T (Itall) and the australian research council.$ef:

A vector subdifferential is defined for a class of directionally differentiable mappings between ordered topological vector spaces. The method used to derive the subdifferential is based on the existcnce of a recession mapping for a positively homogeneous operator. The properties of the recession mapping are discussed and they are shown to he similar to those in the real–valued case. In addition a calculus for the vector subdifferential is developed. Final1y these results are used to develop first order necessary optimality conditions for a class of vector optimization problems involving either proper or weak minimality concepts.     

毛泽东：中国国情与马克思主义中国化

在中国共产党80年历程中,正确认识中国国情,是马克思主义中国化的基本前提。以毛泽东为代表的共产党人在中国革命和建设中,勇于实践,科学认知国情,为马克思主义中国化作出了卓越的贡献,为建设有中国特色社会主义提供了宝贵经验。     

Efficient Oxidation of Alcohols with KBrO 3 in the Presence of Silica Chloride and Wet SiO 2

Alcohols were oxidized to their corresponding carbonyl compounds with KBrO 3 in the presence of silica chloride and wet SiO 2 , in solution and under solvent free conditions.     

赣东北地区下寒武统荷塘组页岩气保存条件分析

通过剖面测量等野外地质调查手段和"X"射线衍射分析等室内实验测试方法,分析了赣东北地区下寒武统荷塘组页岩气赋存的物质基础、孔隙特征、演化特征及构造发育特征等地质条件,在确认了下寒武统荷塘组页岩具有良好生烃条件的前提下,重点研究了荷塘组页岩气的保存条件及其差异性。研究结果表明:研究区页岩气保存条件整体良好,下寒武统荷塘组页岩含气量在(1.0~5.0)m3/t之间;受构造和岩浆活动的影响,不同地区页岩气保存条件存在差异;扬子地块、上饶地块及怀玉山区块在断裂、岩浆活动及成岩作用综合影响下,页岩层构造变形程度大,完整度遭到一定破坏,页岩气保存条件相对较差;玉山区块受后期构造运动影响小,岩浆活动弱,褶皱相对宽缓,下寒武统荷塘组页岩埋深和厚度大,页岩气保存条件相对较好。     

On uniqueness of Kuhn-Tucker multipliers in nonlinear programming

Recently Fujiwara, Han and Mangasarian introduced a new constraint qualification which is a slight tightening of the well-known Mangasarian—Fromovitz constraint qualification. We show that this new qualification is a necessary and sufficient condition for the uniqueness of Kuhn—Tucker multipliers. We also show that it implies the satisfaction of second order necessary optimality conditions at a local minimum.     

Dirichlet and Neumann boundary conditions for the pressure poisson equation of incompressible flow

In a recent paper Gresho and Sani showed that Dirichlet and Neumann boundary conditions for the pressure Poisson equation give the same solution. The purpose of this paper is to confirm this (for one case at least) by numerically solving the pressure equation with Dirichlet and Neumann boundary conditions for the inviscid stagnation point flow problem. The Dirichlet boundary condition is obtained by integrating the tangential component of the momentum equation along the boundary. The Neumann boundary condition is obtained by applying the normal component of the momentum equation at the boundary. In this work solutions for the Neumann problem exist only if a compatibility condition is satisfied. A consistent finite difference procedure which satisfies this condition on non-staggered grids is used for the solution of the pressure equation with Neumann conditions. Two test cases are computed. In the first case the velocity field is given from the analytical solution and the pressure is recovered from the solution of the associated Poisson equation. The computed results are identical for both Dirichlet and Neumann boundary conditions. However, the Dirichlet problem converges faster than the Neumann case. In the second test case the velocity field is computed from the momentum equations, which are solved iteratively with the pressure Poisson equation. In this case the Neumann problem converges faster than the Dirichlet problem.     

武汉市地貌的形成条件与演变过程

本文根据大量地面调查与勘探所得资料,对武汉市地貌的形成条件与演变过程,作了详细的论述。     

乙醇沉淀法回收微量DNA效率的研究

本文研究了浓度、温度、时间和携带DNA等因素对乙醇沉淀法回收微量DNA效率的影响。结果表明:1.回收效率与DNA浓度呈正相关。2.添加携带DNA能提高低浓度DNA的回收效率,浓度越低,增加比例越大.3.超低温(-70℃)、长时间(12h)冷冻处理,对回收效率无明显影响,在室温(+20℃)或低温(-20℃)下放置2～30min同样可获得较高的回收率。