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1.
马明书 《河南师范大学学报(自然科学版)》1995,23(1):23-26
本文给出解抛物型方程的两个高精度的差分格式,其中一个是绝对稳定的三层五点隐格式,另一个是三层六点显格式,稳定性条件是r<1/2,两格式的截断误差均为O(△t^2+△x^4)。 相似文献
2.
解三维抛物型方程的高精度显式格式 总被引:5,自引:0,他引:5
曾文平 《华侨大学学报(自然科学版)》1995,16(2):128-133
提出解三维抛物型方程的两层以及三层的高精度显式差分格式。它们的局部截断误差都是O(Δ(t^2)而稳定性条件分别为r=1/6和r<1/6。 相似文献
3.
曾文平 《华侨大学学报(自然科学版)》1995,16(4):358-362
构造高阶Schrodinger方程iδu/δt+(-1)^mδ^2mu/δx^2m=0的一类半隐式差分格式,给出了它们的稳定性条件。 相似文献
4.
解多维抛物型方程的两个三层显格式 总被引:1,自引:0,他引:1
曾文平 《华侨大学学报(自然科学版)》1996,17(2):118-122
提出两类解N-维抛物型方程的两个三层差分格式。显式格式的稳定性条件是max1≤p≤Nγp≤1/2N,且NΣp=1≠1/2,其中γp=Δt(Δxp)^2,p=1,2,…,N。而显著格式(Ⅱ)当参数a≥1时的无条件稳定的。 相似文献
5.
解四阶抛物型方程的高精度显式差分格式 总被引:5,自引:1,他引:5
曾文平 《华侨大学学报(自然科学版)》1997,18(2):122-127
提出解四阶抛物型方程u1+uxxxx=0的一个三层显式差分格式,其稳定性条件和局部截断误差分别为r=Δt/Δx^4〈1/8和O。 相似文献
6.
曾文平 《华侨大学学报(自然科学版)》1999,20(1):18-24
建立了解二维抛物型方程的一族含参数的绝对稳定的高精度的差分格式,进而,在特殊情况(θ=0,r=1/6)下,得到显式差分格式ω^n+1=(1+1/36□+1/9◇)ω^n,这些格式对任意选取的参数θ≤1/6都是绝对稳定的。且当0≤θ≤min(1/6,1/2-1/12r)时,其收敛阶为O((Δt)^2)。 相似文献
7.
马明书 《河南师范大学学报(自然科学版)》1997,25(1):12-15
本文构造了一个解三维抛物型方程的高精度显格式,截断误差为O(Δt2+Δx4),稳定性条件为r=Δt/Δx2=Δt/Δy2=Δt/Δz2≤1/6,格式表达式简单,应用方便 相似文献
8.
提出解高阶演化方程au/at=a(a^2k+1u)/ax^2k+1的两类新的具有高稳定性的三层显式差分格式,较大地改进了同类格式的稳定性条件,数值例子表明,文中所作的稳定性分析是正确的。 相似文献
9.
对二阶抛物型方程ut=uxx,构造了一族新的三层隐式差分格式(在特殊情况下是两层),它们含有非负参数a1,a2和a3,其截断误差至少可达O(△t)^2+(△x)^4),对三层格式,在条件a1≥a2≥0,a2≤1/2及a1+a2+a3=1之下绝对稳定,特别地,在条件a1=0,a2=a3或a1=a2,a3=0之下成为两层不含参数的隐式格式,且也是绝对稳定的。这些格式均可用追赶法求解,在该格式中,选取适 相似文献
10.
两类新的高稳定性的三层显式差分格式 总被引:2,自引:1,他引:1
曾文平 《华侨大学学报(自然科学版)》1998,19(3):225-231
提出解高阶发展方程au/at=a(a^2k+1u/at^2k+1)(其中a≠0为常数,k=1,2,3,…)的两为新的具有高稳定性的三层显式差分格式,较大地改进了同类格式的稳定性条件。数值例子表明所作的稳定性分析是正确的。 相似文献
11.
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. 相似文献
12.
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. 相似文献
13.
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。 相似文献
14.
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. 相似文献
15.
Miao Maosheng 《华南师范大学学报(自然科学版)》2014,(6)
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- 相似文献
16.
Yang Weitao 《华南师范大学学报(自然科学版)》2014,46(6):137-138
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- 相似文献
17.
Bernard Kirtman 《华南师范大学学报(自然科学版)》2014,(6)
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 相似文献
18.
《上海师范大学学报(自然科学版)》2014,(5):550
<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 相似文献
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《吉林大学学报(理学版)》2014,(5):1105
<正>"Journal of Jilin University(Science Edition)"is a comprehensive academic journal in the fields of science sponsored by Jilin University and administrated by the Ministry of Education of the Peoples Republic of China.The journal started publication in 1955.The original name at starting publication was"Journal of Natural Science of Northeast People University",which was changed into"Acta Scientiarum Naturalium Universitatis Jilinensis"in 1958 owing to the name change of the university.The present journal name has 相似文献