等价替换的推广及在重要极限中的应用

将无穷小量的等价推广到所有量的等价,在f(x)与F(x)等价,且f′(x)与F′(x)等价的条件下,等价替换满足幂指数及对数函数的运算,为1∞型带来更为简便的方法.     

超前型微分差分方程组与常微分方程组的有界解存在性等价问题

本文考虑超前型微分差分方程组在超前量r:(t)较小时,与常微分方程组在唯一的有界解存在性上的等价性问题,在一定情况下证明了两者间的等价性。     

关于单形中几何量的渐近比较

在极限意义下研究单形 ,给出各几何量间的渐近等价刻划     

压差时量的提出及平面单向流变量的等价性

针对平面单向流主动变化量与被动变化量之间函数关系有待明确的问题,提出了压差时量的概念,开展了平面单向流变量之间函数关系研究,在研究中利用压差时量与累积注入量之间的函数关系,结合Buckley Leverett方程和Welge方程,推导了压差时量与出口端含水饱和度、含水率、累积采油量、采出程度之间的函数关系,获得了以下认识：平面单向流任意两个变量之间存在由参数方程所确定的函数关系,压差时量是参数方程的参数;平面单向流中的变量具有等价性。根据以上认识,以层间矛盾研究为例,利用压差时量概念和变量等价性研究了层间矛盾产生的机理。压差时量的概念和变量等价性的认识,明确了主动变量与被动变量之间的函数关系,建立了驱替过程中各变量之间的等价关系,该认识对相关理论问题和应用问题的研究起到一定促进作用。     

线性中立型系统的渐近稳定性

自从秦元勋教授于1958年提出微分差分方程与微分方程之间在稳定性理论中的等价性的问题以来,出现了不少这方面的研究工作,(如[1][2][6]等)、然而,这些工作大都是集中于对小滞量时滞系统研究它们与各自退化系统(滞量为0)之间关于稳定性的等价性,我们在文[8]中引进微分差分方程的近似系统(常微分方程组)建建立了缓变系数线性滞后系统与其近似系统关于渐近稳定的等价性定理,在本文中,我     

关于伴随函子的等价定义

伴随是范畴论中最重要的概念之一．其定义涉及多个量且难以理解。介绍了伴随函子的几个等价定义,证明了各个定义的相互等价性．从而可以更加直观地理解伴随函子的定义．并给出了伴随函子的应用例子。     

滞量对解存在唯一性的影响

本文讨论滞量对非线性差分微分方程解的存在唯一性的影响,在关于滞量为等价与结构稳定性的定义之下,给出了若干例子与结构稳定的充分条件。     

一类非线性演化方程及其等价类

本文导出与谱问题相联系的一类变系数非线性演化方程。作者证明了它与另一类演化方程等价,并证明了这两个等价类的单孤立子一一对应。在附录中给出散射量与时间的依赖关系,顺便糾正了文献[7]中的一个错误。     

可处理多个无序量测的前向滤波算法

基于等价量测和前向滤波法,推导出一种单个无序量测算法Fl1,并说明了该算法与Al1算法、FPFD算法以及AA1算法之间的等价性.以Fl1算法为基础提出可以处理同时到达融合中心的多个不同单步延迟无序量测的最优算法CZ1.所提新算法的性能不依赖过程噪声的离散化模式,且无须对状态转移矩阵求逆.仿真结果表明在过程噪声DCM下CZ1算法与CA1算法的性能是相同的.     

偏微分演化方程的代数动力学解法中无穷小时间平移算子的等价构造

我们给出了王顺金等提出的偏微分演化方程的代数动力学解法中关于时间平移的无穷小算子L的等价构造形式,我们的形式只涉及简单的偏导数运算,避免了在运用王-张时间平移算子进行计算的时候出现的大量的δ函数的导数.我们给出了两种表示的等价性,即王顺金等价性定理的证明.作为应用,利用我们给出的无穷小算子L的构造,处理了非线性对流方程,Burgers方程,非线性Schrdinger方程,KdV方程以及sine-Gordon方程等几个典型方程,并计算到至少二阶展开项,这些例子包括了实场量和复场量情形以及对时间的一阶导数和二阶导数情形.     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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