矩阵分块运算求解线性方程组

运用矩阵的分块计算规则，对方程组AmnXn=bm进行讨论，并给出求解方法。     

类P-双调和方程的无穷多解问题

考虑了类P-双调和方程△（a（｜△u｜^p）｜△u｜^p-2△u）=f（x，u）的Dirichlet零边值问题的无穷多解问题，这里的非线性项是奇的，通过验证所定义的泛函满足Cerami条件．从而运用喷泉定理，得到了无穷多个大能量解的存在性．     

Which events can cause iteration in instructional design? An empirical study of the design process

Instructional design is not a linear process: designers have to weigh the advantages and disadvantages of alternative solutions, taking into account different kinds of conflicting and changing constraints. To make sure that they eventually choose the most optimal one, they have to keep on collecting information, reconsidering continuously whether their own decisions are still justified in the light of the latest insights. We have studied the role of iteration during instructional design. For our research, we have used an ISD-based method for the specification of training simulators. During our empirical evaluation study, we introduced five events that are likely to cause iteration. The results show that the quality of the designs is not directly related to the amount of iteration. We conclude that there are different kinds of iteration, triggered by different kinds of actions and events. We propose a list of triggers for iteration some of which originate from outside (new information, new opinions/arguments and acquisition procedures); others are caused by, or evolve from interaction with the design process itself (discovery of missing input, need to repair errors, new insights based on work later on in the design process, and new ideas of the designers). in final form: 4 August 2005     

一致凸Banach空间非扩张映象带双误差的Ishikawa迭代

在一致凸Banach空间上，研究了半紧的非扩张映象‖Tx-Ty‖≤‖x—y‖的Ishikaww序列的收敛问题，建立并证明了带双误差的Ishikawal迭代逼近收敛定理，从而推广并改进了某些已知的结果．     

关于城市维护建设税存在的问题及改进设想

城市维护建设税自开征以来,收入逐年增加。城市维护建设税的开征,对城市的公用事业和公共设施的维护和建设,起了重要的作用。但是,随着我国改革开放的不断深化和经济的不断发展,城市维护建设税本身存在的不足日益显露出来。本文就城市维护建设税所存在的主要问题,谈谈改革的具体设想。     

一类四阶非线性波动方程整体解的存在性

借助线性问题的衰减估计，在一适当的Banach空间，利用整体迭代法证明了一类非线性四阶波动方程Cauchy问题整体解的存在性     

Simple shear endochronic eqiations for finite plastic deformation

The endochronic equations proposed by Valanis (1980) were extended to a finite deformation range. Jaumann's rate,Fu's rate and Wu's rate were incorporated into the endochronic equations to analyze simple shear finite deformation. Incremental equations and numerical solutions are deduced for three endochronic objective models. The results show that an oscillatory shear stress response to a monotonically increasing shear strain occurs when the Jaumann's rate objective model is employed for endochronic materials. The oscillatory response is dependent on the adopted objective rate. Compared with the Jaumann's rate, the Fu's rate and the Wu's rate satisfy the restrictions to elastic-plastic constitutive relations and are in agreement with the experimental results.     

求解一类反控制方程周期解

本文运用迭代方法研究了非线性自治方程dudt=f(u,λ),u(0)=u(T),的周期解及其在反控制方程x=yy=z2中的应用。z=-λz-y-x x     

非线性三阶边值问题正解的存在性

利用上、下解方法,研究三阶微分方程解与正解的存在性.然后给出了所获结果的一个应用.     

Unrealistic responses to realistic problems with missing information: what are important barriers?

Abstract

It is a well-documented finding that students tend to neglect their real-world knowledge when solving word problems, even when realistic assumptions are needed. Although studies have successfully shown the extent to which students tend to provide unrealistic responses, the question of where this tendency comes from has yet to be answered. We focused on two major steps needed to solve realistic word problems: noticing missing information and making realistic assumptions. We conducted two studies with fifth graders (Study 1, N?=?108; Study 2, N?=?60) in which we compared students’ (un-)realistic responses to problems that differed in how obvious the missing information was. Study 1 fostered only students’ ability to make assumptions. Study 2 fostered this ability plus the ability to notice missing information. The results indicate that, if the missing information is not obvious, students’ failure to notice it seems to be what prevents them from arriving at a realistic solution.