复数域上矩阵相似于对角形的一个充要条件

本文我们将给出复数域上矩阵相似于对角形的一个充要条件。定理:设V 为复数域C 上n 维线性空间,(?)为V 的一个线性变换,则(?)在某组基下的矩阵为对角形的充要条件是:对于A 的每一特征值λ有     

对角形退缩椭圆型方程组弱解的局部正则性

本文得到对角形退缩椭圆型议程组弱解的某些积分估计,证明了弱解的局部Holder连续性,并把此结果推广至一类非对角形的情形.     

一类对角占优矩阵奇异性的判别

利用矩阵列向量组线性相关性的相关性质,得到了一类特殊对角占优矩阵奇异的一个充要条件.     

矩阵与对角形矩阵相似的条件研究

对角形矩阵是最简单的一类矩阵,而相似矩阵有相同的特征根,特征多项式,特征向量,最小多项式,初等因子．因此,研究矩阵与对角形矩阵相似的条件十分重要．本文从不同角度讨论了若干个矩阵与对角形矩阵相似的条件．     

四元数矩阵到复矩阵的相似变换

给出四元数体上λ多项式的线性因式分解定理和四元数体上方阵的特征矩阵主法式的存在唯一性定理。用之导出四元数方阵所相似的Jordan形主矩阵的唯一性,四元数矩阵相似于对角形矩阵的一个充要条件及四元数方阵的最小实系数零化多项式的形式。     

矩阵可交换的充要条件

本文利用矩阵的张量积给出与n阶方阵A可交换的矩阵为A的多项式的充要条件,然后利用特征多项式给出与准对角形矩阵可交换的矩阵皆为准对角形矩阵的充要条件.     

用行初等变换化实对称矩阵为对角形

给出了主要用行初等变换化实对称矩阵为对角形式的方法, 即先化实对称矩阵为上三角矩阵, 则三角矩阵主对角线上的元素所成对角矩阵为实对称矩阵的对角形.     

汽车变速器传动齿轮对角修形量计算方法

针对汽车变速器齿轮传动中的振动及噪声问题,从齿轮几何学角度出发,提出了斜齿轮副对角修形量的计算方法.根据齿轮啮合原理,建立了斜齿轮副两啮合工作齿面满足任意瞬时连续相切接触条件的啮合方程,并将方程求解转化为两啮合齿面法向间距最小以及法向量偏差最小的优化问题,从而确定了对角修形量.同时,基于Masta仿真平台建立目标变速器的三维模型,并根据对角修形的参数对目标齿轮副的啮合性能进行仿真试验验证.仿真试验表明,变速箱主减速齿轮副对角修形后常用工况下的传动误差明显降低,齿面载荷分布更加合理.     

双严格对角占优矩阵线性互补问题的最优误差界

针对H-矩阵线性互补问题误差界的估计式,利用双严格对角占优矩阵的性质和函数的单调性,得到了含有参数的双严格对角占优矩阵线性互补问题的误差界,并确定了其最优值.     

弱链对角占优B-矩阵线性互补问题的误差界估计

利用弱链对角占优M-矩阵的逆矩阵的无穷大范数的范围,给出了弱链对角占优B-矩阵线性互补问题误差界新的估计式,进而给出B-矩阵线性互补问题误差界的估计式.新估计式改进了已有文献的结果.     

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.     

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

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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