用初等变换求长方形矩阵的逆

已知矩阵Ａ，求矩阵Ｂ，使得ＡＢ＝Ｉ。对于Ａ是可逆方阵时，我们已知道怎样求矩阵Ｂ；当Ａ是ｎｘｎ的长方形矩阵时，又怎样求Ｂ呢？本文将给出一个方法－先把Ａ增广为可逆方阵，再用初等变换法求之。     

一个矩阵方程的又一特征条件

给出了满足ＡＡ＝Ａ＾２Ｂ的特征条件，这里矩阵ＡＡ＾＊与Ｂ可交换，且Ｂ是非奇异的矩阵，这是文「１」的结果的推广。     

一个矩阵方程的特征条件

给出了满足ＡＡ＾＊－Ａ＾２Ｂ的特征条件，这里矩阵ＡＡ＾＊与Ｂ可交换且Ｂ是非奇异的正规矩阵。     

两个复矩阵乘积的特征值估计

设Ａ，Ｂ是两个ｎ阶复矩阵，且ｒ（ＡＢ－ＢＡ）≤１，利用Ａ，Ｂ的特征值给出了乘积矩阵ＡＢ的特征值的取值范围，推广了关于可换Ｈｅｒｍｉｔｅ矩阵乘积的特征值估计的一些结果。     

广义对称特征值问题（A—λB）x=0的解的结构与算法

对Ａ、Ｂ∈Ｒ＾ｎｘｎ对称，Ｂ正半定情形的广义特征值问题（Ａ－λＢ）ｘ＝０给出了求解方法，分析了矩阵对（Ａ，Ｂ）为奇异对时的特征值与特征向量的结构，所用的矩阵变换为正交变换，故计算过程是稳定的。     

关于矩阵乘积迹的两个问题

关于矩阵乘积迹的两个问题刘希普，黄少通文［１］证明了下述两个不等式成立：（１）设Ａ为Ｈｅｒｍｉｔｅ矩阵，Ｂ为斜Ｈｅｒｍｉｔｅ矩阵，则ｔｒ（ＡＢ）￣２＞ｔｒＡ￣２Ｂ￣２；（２）设Ａ，Ｂ均为余Ｈｅｒｍｉｔｅ矩阵，则ｔｒ（ＡＢ）￣２≤ｔｒ（Ａ￣２Ｂ￣２）。...     

Z矩阵的一些性质

倘若矩Ａ＝ｔＩ－Ｂ,Ｂ≥０,则称Ａ是一个Ｚ矩阵;若还有ｔ≥ｐ（Ｂ）,则称Ａ为Ｍ矩阵,该文主要研究非Ｍ矩阵但是Ｚ矩阵的矩阵的性质,获得一些有趣的结果。     

二阶矩阵的Bellman迹不等式

Ａ、Ｂ是二阶非负定矩阵时，证明了：ｔｒ（ＡＢ）＾ｎ≤ｔｒ（Ａ＾ｎＢ＾ｎ）（ｎ为自然数），此结果说明Ｒ．Ｂｅｌｌｍａｎ猜想对二阶矩阵成立。     

关于完全正矩阵的几点注记

ｎ阶矩阵Ａ称为完全正的，如果Ａ有分解：Ａ＝ＢＢｔ，其中Ｂ为（不必方）元素非负矩阵．Ｂ的最小可能列数称为Ａ的分解指数．本文给出了一个５×５阶双非负矩阵Ａ为完全正的充分条件．     

相容矩阵方程AXB=D的极小范数解及其稳定性

给出了相容矩阵方程ＡＸＢ＝Ｄ的极小范数解的结构，并在Ａ＝Ａ＋δＡ，Ｂ＝Ｂ＋δＢ，Ｄ＝Ｄ＋δＤ的扰动下分析了矩阵方程ＡＸＢ＝Ｄ极小范数解的稳定性。     

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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