在恒等算子处可乘的弱连续映射

设H是复数域上的无限维Hilbert空间,(φ)是B(H)到自身弱连续的线性满射.得到了(φ)为自同构的充要条件是φ在恒等算子I处可乘.     

基于图像分解的分层图像修复

We propose a layered image inpainting scheme based on image decomposition.The damaged image is first decomposed into three layers:cartoon,edge,and texture.The cartoon and edge layers are repaired using an adaptive offset operator that can fill-in damaged image blocks while preserving sharpness of edges.The missing information in the texture layer is generated with a texture synthesis method.By using discrete cosine transform(DCT)in image decomposition and trading between resolution and computation complexity in texture synthesis,the processing time is kept at a reasonable level.     

催化动力学光度法测定痕量钯——次磷酸钠—钯(Ⅱ)—孔雀绿体系

基于醋酸——醋酸钠缓冲容液(pH=4.75)中,痕量钯(Ⅱ)催化次磷酸钠还原孔雀绿褪色反应,建立了痕量钯的催化动力学光度分析新方法.方法的最低检测限为2.273×10~(-10)g/ml,线性范围0.1～0.8μg/25ml,方法应用于模拟试样的测定,结果满意.     

2n阶J-自伴算子的谱是离散的充分条件

借助Naimark关于2n阶对称微分算式所生成最小算子L0之任何自伴扩张Lu的谱是离散的充分条件定理，利用Lidskii方法，得到了2n阶J-自伴微分算子的谱是离散的另一个充分条件．     

非线性强伪压缩算子方程的三重迭代及其收敛性分析

提出了在一致光滑Banach空间中不带连续性条件的非线性增生算子方程的三重迭代程序,并研究了其收敛性问题.该文所得到的结果在更一般的条件下完善和扩展了以往的相关结论。     

关于Г-顺从性的几点注记

明确了Γ-顺从群研究中关键集合U(G,Γ={Sφf∶φ∈P1(Γ),f∈L∞(G)}。透过测度,讨论了G为Γ-顺从和Γ为顺从群之间的条件关系,并从伴随算子角度对Γ-顺从性进行了新的刻画     

赋值格为险象识别格的一种非经典逻辑系统K#(Ⅱ)

研究赋值格为非线性序的一种非经典逻辑低矺#.在该系统中,格结构不同于Boole代数,蕴涵算子→取Kleene-Dienes算子RKD.得到若干结果,特别是K#-准重言式恰是经典命题逻辑C2中的重言式,从而也等于C2中的定理,即QT(K#)=T(C2)=Φ├ .     

欧氏空间Rs^n上的自共轭变换

本文探讨了Rs^n上的自共轭变换的性质与广义实对称矩阵的几何背景。     

Drawing on a Theoretical Model to Study Students’ Understandings of Fractions

Teaching and learning fractions has traditionally been one of the most problematic areas in primary school mathematics. Several studies have suggested that one of the main factors contributing to this complexity is that fractions comprise a multifaceted notion encompassing five interrelated subconstructs (i.e., part-whole, ratio, operator, quotient, and measure). Kieren was the first to establish that the concept of fractions is not a single construct, but consists of several interrelated subconstructs. Later on, in the early 1980s, Behr et al. built on Kieren’s conceptualization and suggested a theoretical model linking the five subconstructs of fractions to the operations of fractions, fraction equivalence, and problem solving. In the present study we used this theoretical model as a reference point to investigate students’ constructions of the different subconstructs of fractions. In particular, using structural equation modeling techniques to analyze data of 646 fifth and sixth graders’ performance on fractions, we examined the associations among the different subconstructs of fractions as well as the extent to which these subconstructs explain students’ performance on fraction operations and fraction equivalence. To a great extent, the data provided support to the associations included in the model, although, they also suggested some additional associations between the notions of the model. We discuss these findings taking into consideration the context in which the study was conducted and we provide implications for the teaching of fractions and suggestions for further research.     

由强单调T2空间导出的一类新算子

证明了若拓扑空间X是强单调T2紧的,则对X中的任意闭集K和任意的n>n 0(n0∈ω)存在一个闭集δ(K,n)满足(i) K=∩n≥n0 δ(K,n);(ii)对任意n≥n0,δ(K,n+1)( )δ(K,n);(iii)如果K,H均是闭的且K( )H,则有δ( K,n)( )δ(H,n).