基于矩阵分裂的预条件SOR迭代法收敛性

对预条件方法解线性方程组,利用黄廷祝等在["modified SOR-type iterative method for z-matri-ces"]中提到的预条件能加速SOR迭代法的收敛性,结合矩阵分裂理论及比较定理,给出一种基于矩阵分裂的含参数预条件SOR迭代方法,说明这种方法不仅能加速SOR迭代法的收敛性,而且优于一般的预条件方法,找出参数的最优选取方法,最后通过数值例子加以说明.     

一类新预条件下AOR迭代法收敛性的讨论

对AOR迭代法解线性方程组,讨论在一类新的预条件下AOR迭代法收敛性的加速,证明在非奇异M-矩阵下该预条件加速AOR迭代法的收敛性,而在非奇异不可约M-矩阵下能严格加速AOR迭代法的收敛性.最后给出一个例子说明该预条件要优于通常的预条件(I+S).     

一类预条件后AOR迭代法中的最优参数选取

解大型线性方程组 Ax=b时,运用预条件P=(I C)加速AOR迭代方法的收敛性,并得到预条件后AOR迭代法中最优参数的选取.最后给出一个数值例子.     

矩阵非负分裂下SOR迭代法收敛性

目的讨论预条件后用迭代法求解的线性方程组Ax=b。方法利用预条件后系数矩阵非负分裂形式的多样性,给出一种含参数形式的非负分裂。结果与结论证明这种分裂形式可以加速SOR迭代法的收敛性,并与一般的预条件后SOR迭代法的收敛性进行比较,说明这些分裂形式更好。     

改进矩阵分裂形式的预条件SOR迭代法收敛性讨论

结合矩阵分裂理论及比较定理,给出一种改进矩阵分裂形式的预条件含参数SOR迭代方法,证明这种方法不仅能加速SOR迭代法的收敛性,而且优于一般的预条件方法,并找出参数的最优选取.最后通过数值例子加以说明.     

预条件(I+S)后改进矩阵分裂的SOR迭代法收敛性分析

目的在预条件后运用SOR迭代法求解大型线性方程组Ax=b,以加快迭代法的收敛性。方法结合矩阵分裂理论及比较定理,引入参数α,给出预条件后一种改进的矩阵分裂形式,使矩阵分裂更加一般化。结果与结论说明这种方法不仅能加速SOR迭代法的收敛性,而且优于常见的SOR方法,并且给出参数的最优选取,为算法设计提供帮助。     

预条件[I+S(α)]加速2PPJ型方法的收敛性

Hiroshi Niki等讨论在预条件Ps=I＋S下加速Gauss—Seidel迭代法的收敛性，本文讨论在预条件含参数的情况下解线性方程组Ax=b，通过预条件提高Jacobi型方法的收敛性。进而使两参并行Jacobi型方法（简称2PPJ方法）的收敛性得到加速。最后给出一个数值例子。     

预条件下2PPJ型方法收敛性的加速

Hiroshi Niki等讨论在预条件PS=I S下加速Gauss-Seidel迭代法的收敛性,该文讨论在预条件PC=(I C)下解线性方程组Ax=b,通过预条件提高Jacobi型迭代方法的收敛性,进而使两参并行Jacobi型方法(简称2PPJ方法)的收敛性得到加速,最后给出一个例子.     

一种改进预条件的AOR迭代法收敛性的讨论

提出了一种改进预条件的AOR迭代法,并证明了在非奇异M-矩阵下,该改进预条件加速了AOR迭代法的收敛性.通过理论分析和数值实验验证,该方法均优于文献中所提出的预条件方法(I+S).     

改进的JOR迭代法的收敛性定理

基于严格双α-对角占优的概念,针对线性方程组Ax=b在求解时常用的JOR迭代方法,给出了JOR迭代矩阵谱半径新的上界及迭代法的收敛性准则.该准则不仅适用于双严格对角占优矩阵类,还适用于严格双α-对角占优矩阵类,对相应迭代矩阵谱半径的估计也更精确,且扩大了JOR方法收敛参数的选取范围,并用数值例子说明了所给结果的优越性.     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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