Zakharov方程组全离散Fourier谱格式的稳定性

为研究等离子体物理中Zakharov方程组数值方法解的适定性,讨论了全离散Fourier谱格式的稳定性。首先证明了误差eMn+1的L2模,其次证明了eMn+1和ηMn+1的能量模,最后借助全离散Fourier谱格式的守恒性质,证明了Zakharov方程组全离散Fourier谱格式解的稳定性。该研究改进了半离散Fourier谱格式只在空间方向上的稳定性,得到了全离散Fourier谱格式解在时间方向和空间方向上的稳定性定理。     

人口发展方程的一个差分格式的收敛性和稳定性

<正> 人口数值计算是人口学定量分析的一个重要方面。文给出了供数数值计算用的两种差分格式。即显格式和隐格式;并证明了显格式是稳定的。本文继而证明了隐格式在一定的条件下收敛和稳定。 如所知,人口的发展方程为     

一类非线性方程隐式格式的稳定性分析

本文针对RLW方程提出一个守恒型隐式差分格式,并对该格式的格式的截断误差进行了分析,证明了格式的稳定性与收敛性。     

三阶隐迭代格式的收敛性

在Banach空间X的非空闭凸子集上引入了一类新的带有限李普希兹算子集三阶隐迭代格式,借助于压缩映像原理证明了迭代格式定义的合理性,在适当的条件下,证明了该迭代格式中各个点列的收敛性．     

带五次项的非线性Schrodinger方程的一个紧致差分格式

对带五次项的非线性Schrodinger方程提出了一个紧致差分格式,使格式的收敛阶达到 O（τ2＋ h4）。运用能量的方法证明了离散的守恒律,并证明了差分格式的稳定性与收敛性。数值实验结果验证了理论的证明。     

带五次项的非线性Schrdinger方程的一个紧致差分格式

对带五次项的非线性Schrdinger方程提出了一个紧致差分格式,使格式的收敛阶达到O(τ2+h4).运用能量的方法证明了离散的守恒律,并证明了差分格式的稳定性与收敛性.数值实验结果验证了理论的证明.     

6阶收敛的牛顿迭代修正格式

给出两种牛顿迭代法的修正格式,证明了该迭代格式是六阶收敛到单根.数值实验表明,与其它已知的牛顿迭代格式相比,该迭代格式具有一定的优越性.     

一类半线性波动方程的整体吸引子

本文考虑了一类一维带阻尼的半线性波动方程,建立了半离散的Legerldre谱格式,分析了由这种谱格式生成的离散系统的动力性质,在有限时间段（0,T],证明了这个离散动力系统的整体吸引子的存在性,并证明了半离散的Legendre谱格式解的稳定性和收敛性。     

求解非线性函数零点的一种迭代格式及其收敛性

就求解一类函数零点问题,建立了一种简捷有效的迭代格式,并证明了这种迭代格式的收敛性.     

一种计算激波的守恒差分格式

介绍了一种处理激波间断解的差分格式,此格式是基于在间断解的两侧使用不同计算公式的守恒差分格式;证明了该格式满足离散熵条件。     

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