凸度量空间上的一个不动点定理

设Ｘ为具有性质（Ｃ）和（Ｐ）的凸度量空间，Ｋ是Ｘ的非空凸子集，ＴＫ→２Ｘ使得ｘ→ｄ（ｘ，Ｔｘ）是１．ｓ．ｃ．若ｉｎｆ｛ｄ（ｘ，Ｔｘ）｜ｘ∈Ｋ｝＝０，且ｘ，ｙ∈Ｋ，λ∈［０，１］，ｕ＝Ｗ（ｘ，ｙ，λ）有ｄ（ｕ，Ｔｕ）≤Φ（ｍａｘ｛ｄ（ｘ，Ｔｘ），ｄ（ｙ，Ｔｙ）｝）．这里ΦＲ＋→Ｒ＋满足条件Φ（０）＝０，在０的右边不减和连续，则Ｔ在Ｋ上有不动点．它推广了Ｔ．Ｈ．Ｃｈａｎｇ和Ｃ．Ｌ．Ｙｅｎ（１９８９）在Ｂａｎａｃｈ空间中的结果     

非线性增殖和耗散算子方程的迭代解

设Ｘ是一致光滑Ｂａｎａｃｈ空间和Ｔ：Ｄ（Ｔ）∪→Ｘ→Ｘ是一连续增殖算子，Ｄ９Ｔ）和Ｒ９Ｔ）分别表Ｔ的定义域和值域。对任意给定的ｆ∈Ｘ，由Ｓｘ＝－Ｔｘ＋ｆ。Ａ↓ｘ∈Ｄ（Ｔ），定义映象；Ｓ：Ｄ（Ｔ）→Ｘ，作者证明，在适当条件下，关于Ｓ的Ｍａｎｎ迭代序列和Ｉｓｈｉｋａｗａ迭代序列强收敛于方程ｘ＋Ｔｘ＝ｆ的唯一解。     

LaSalle矩阵不等式的加强

设Ａ是ｎｘｎ 非奇异矩阵,Ｂ是ｎｘｎ 对称矩阵,且Ｇ＝ － （ＡＴＢ＋ ＢＡ） 正定,那么对任意ｘ,ｙ ∈Ｒｎ,且ｘ ≠０,有（Ｂｘ ＋ ｙ）ＴＧ－ １（Ｂｘ ＋ ｙ） ≥〔ｘＴ（ＡＴ）－ １（Ｂｘ ＋ ｙ）〕２ｘＴ（ＡＴ）－ １ＧＡ－ １ｘ ≥－ ２ｙＴＡＴｘ     

非线性特征值问题的大范围求解

本文考虑非线性特征值问题：ｆ（ｘ）一λｘ＝０，ｘ￣Ｔｘ一１＝０，ｘ∈Ｒ￣ｎ的求解问题。证明了：（１）当ｎ为奇数；（２）对任意自然数ｎ，当为对称矩阵时，方程至少存在二个实解（或一个重解），同时给出了大范围求解方法，并计算了数值例子。     

环的若干交换性定理

设Ｚ（Ｒ）为环Ｒ的中心。本文证明了满足下列条件之一的环Ｒ是交换环：（Ａ１）Ｒ是半素环，且对任意ａ１，ａ２，…，ａｎ∈Ｒ，存在整系数多项式ｆ（ｘ１，ｘ２，…，ｘｎ）及ｎ元置换σ，使得ａ１ａ２…ａｎ－ａσ（１）ａσ（２）…ａσ（ｎ）ａ１ｆ（ａ１，ａ２，…，ａｎ）∈Ｚ（Ｒ）；（Ｂ１）对任意ａ１，ａ２∈Ｒ，存在整系数多项式ｆ（ｘ１，ｘ２）及２元置换σ，使得ａ１ａ２＝ａσ（１）ａσ（２）ａ１ｆ（ａ１，ａ２）。     

半素环的一个交换性定理

证明了半素环Ｒ为交换的，如果它满足条件（αｋ）：对任意ａ，ｂ∈Ｒ，存在一个字长＞Ｋ且含有（ｘｙ）２（或（ｙｘ）２）的字Ｗ（ｘ，ｙ）及一个能被Ｗｘ（ｘｙ）整除的整系数多项式ｆ_Ｘ（ｘ，ｙ），使得ａｂ~Ｋ－ｆ_Ｘ（ａ，ｂ）∈Ｚ（Ｒ），其中Ｋ是一个给定的正整数，ＷＸ（ｘ，ｙ）与ＦＸ（ｘ，ｙ）均可随Ｘ－（ａ，ｂ）而变，Ｚ（Ｒ）是环Ｒ的中心。     

Lurie型鲁棒控制系统的绝对稳定性

在实数Ｒ上一切闭区间组成的集合和区间矩阵的集中中引进了代数运算，讨论了Ｌｕｒｉｅ型直接鲁棒控制系统ｘ＝Ｇ「Ｂ，Ｃ」ｘ＋Ｇ「Ｒ，Ｓ」ｆ（σ）；σ＝ｃ＾Ｔｘ，ｆ（．）∈Ｋ「０，∞」和间接鲁棒控制系统ｘ＝Ｇ「Ｂ，Ｃ」ｘ＋Ｇ「Ｒ，Ｓ」ｆ（σ）；σ＝ｃ＾Ｔｘ－．ｆ（．）∈Ｋ「０，∞」display structure     

结合环的几个交换性条件

设Ｚ（Ｒ）为环Ｒ的中心。本文证明了满足下列条件之一的环Ｒ必为交换环：（１）Ｒ是Ｋｏｅｔｈｅ半单纯环，且对任意ａ，ｂ∈Ｒ，均存在一个非负整数Ｋ－Ｋ（ａ，ｂ）及一个整系数多项式ｆｘ（ｘ，ｙ）（它的每一个单项式均含有ｓ＝ｓ（ａ，ｂ）（＞１）个ｘ和ｔ＝ｔ（ａ，ｂ）（≥Ｋ）个ｙ）使ａｂ＾ｙ－ｆｘ（ａ，ｂ）∈Ｚ（Ｒ）；（２）Ｒ是Ｂａｅｒresume     

关于平方类非扩展映象的不动点

作者在［１］中讨论了完备度量空间中的平方类映象的不动点定理,本文类似地建立了一类平方类非扩展映象。设ｘ是完备的度量空间,Ｔ是Ｘ上的自映象,若满足条件：｛ｄ（Ｔｘ,Ｔｙ）｝２≤１２（ｄ（ｘ,Ｔｙ）ｄ（ｘ,Ｔｘ）＋ｄ（ｙ,Ｔｘ）ｄ（ｙ,Ｔｙ））　ｘ,ｙ∈Ｘ（Ｉ）则称Ｔ是Ｘ上的平方类非扩展映象。一、主要结论定理　设Ｘ是完备的度量空间,Ｔ是Ｘ上的平方类非扩展映象,则Ｔ在Ｘ中有唯一的不动点ｚ,且ｘ０∈Ｘ,迭代序列ｘｎ＝Ｔｘｎ－１（ｎ＝１,２…）收敛到２。二、几个引理引理１　设Ｘ,Ｔ满足定理中的条件,则…     

二维纳米材料［Cd_xMg_（6－x）Al_2（OH）_（16）］~（2＋）［

用中温水热合成的方法，合成了类水滑石［Ｃｄ＿ｘＭｇ＿（６－ｘ）Ａｌ＿２（ＯＨ）＿（１６）］￣（２＋）［Ｓ·２Ｈ＿２Ｏ］￣（２－），用ＸＲＤ、ＦＴ－ＩＲ，ＤＴＡ─ＴＧ等手段进行了表征，讨论了它的热稳定性。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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