线性模型参数估计中的效率

对一般的ＧａｕｓＭａｒｋｏｆ模型：Ｙ＝Ｘβ＋ｅ,Ｅ（ｅ）＝０,Ｃｏｖ（ｅ）＝σ２Ｖ,Ｖ≥０,给出了μ＝Ｘβ的最小二乘估计的３种相对效率和它们的下界．对一般的方差分量模型：Ｙ＝Ｘβ＋ｅ,Ｅ（ｅ）＝０,Ｃｏｖ（ｅ）＝∑ｔｉ＝１θｉＶｉ,θｉ＞０,Ｖｉ≥０,相拟地定义了μ＝Ｘβ的最小二乘估计的３种相对效率并给出了它们的下界．     

多元回归系数非齐次线性估计在新的优良性准则下的容许性

考虑多线性模型Ｙｎｘｍ＝ＸＨｐｘｍ＋ε，Ｅ（ε）＝０，Ｃｏｖ（＾→ε）＝ＶｎｘｍＸＵｎｘｍ，和矩阵损失函数：（Ｄ－ＳＨ）（Ｄ－ＳＨ）′，其中Ｘ和Ｕ≥０和已知矩阵，Ｈ和Ｖ≥０（但Ｖ≠０）是未知参数矩阵，本文在新的容许性意义下，得到了ＳＨ的非齐次线性估计ＬＹ＋ａ在非齐次线性估计类￡中是可容许的充要条件。     

相依回归系统回归系数改进估计的可容许性

考虑相依回归系统ｙｉ＝Ｚｉβｉ＋εｉＥ（εｉ）＝０,ＣｏＶ（εｉ,εｊ）＝σｉｊＩｎ,ｉ,ｊ＝１,２｛（１）这里ｙｉ为ｎ×１观察向量,Ｚｉ为ｎ×ｍｉ观察矩阵且满列秩,βｉ为ｍｉ×１的未知回归系数,εｉ为ｎ×１随机误差向量,Ｖ＝（σｉｊ）为二阶正定对称...     

一类约束下的参数估计问题

考虑线性模型ｙｎ×１＝Ｘｍ×ｐβｐ×１＋εｎ×１，（１）其中ｙｎ×１为样本观测值，Ｘ为ｎ×ｐ阶的设计阵，β为ｐ维参数向量，εｎ×１为ｎ维随机向量，ε为随机误差．Ｅε＝０，Ｄε＝σ２Ｖ这里σ２已知或未知皆可，Ｖ为ｎ×ｎ阶非负定阵．对于线性模型（１），...     

增长曲线模型中LSE的几种新的相对效率

对于生长曲线模型Ｙｑ×ｎ ＝ Ａｑ×ｍ Ｂｍ ×ｋＣｋ×ｎ ＋ ｅｑ×ｎ , Ｅ（ｅ） ＝ ０ ,ｃｏｖ（→ｅ） ＝ Ｖｎ×ｎ ｑ×ｑ ,该文定义了四种ＬＳＥ 的相对效率,并给出了它们的上界     

二阶半线性微分各分方程的奇摄运边值问题

本文研究微分积分方程奇摄动边值问题εｄ＾２ｙ／ｄｔ＾２＝ｇ（ｔ，ｙ，ｊ，ε），ｙ（０，ε）＝ｙ（１，ε）＝０，０〈ε《１，其中Ｊ＝ψ（ｔ，ε）＋∫＾α０Ｋ（ｔ，ｓｙ（ｓ，ε），ε）ｄｓ，ａ＝１或ｔ。首先利用边界层函数法构造了这个问题解关于√ε的形成渐近展开，然后证明该问题解的局部存在唯一性以及所构造渐近级数的一致有效性。     

二阶非线性抛物型偏微分方程初边值问题的奇摄动

本文讨论一类二阶非线性抛物型偏微分方程初边值问题的奇摄动解法，设Ｌεｕ＝δｕ／δｔ－〔εΣ↑ｎ↓ｉｊ＝１δｉｊ（ｘ，ｔ）δ＾２ｕ／δｘｉδｘｊ＋Σ↑ｎ↓ｉ＝１ｂｉ（ｘ，ｔ）δｕ／δｘｉ＋Ｃ（ｘ，ｔ，ｕ）〕＝０ ｕ（ｘ，ｔ，ε）│ｔ＝０＝ｕ（ｘ，０，ｔ）＝μ（ｘ，ε），ｘ∈Ｂ↑－ ｕ（ｘ，ｔ，ε）│ｓ＝ｈ（ｘ，ｔ，ε）│ｓ（ｘ，ｔ）∈Ｓ其中ε〉０是小参数，给出了上述问题的解的渐近展开式。利用比较定理     

Gauss—Markoff和方差分量模型中LSE的一种新的相对效率

对Ｇａｕｓｓ－Ｍａｒｋｏｆｆ模型：Ｙ＝Ｘτ＋ｅ，ｅ￣（０，ο＾２Ｖ），Ｖ≥０，τ的ＬＳＥ的一种新的相对效率被提出来并得到了其下界，对方差分量模型：Ｙ＝Ｘτ＋ｅ，ｅ￣（０，ｍΣｉ＝１ο＾ｉＶｉ），Ｖ＝ｍΣｉ＝１Ｖｉ≥０，τ的ＬＳＥ的一种新的相对效率也被提出来并得到了独立于未知参数的下界。     

某类双参数非线性系统初值问题的双重边界层现象

研究奇摄动双参数非线性系统初值问题εｙ＂＝Ｆ（ｔ,ｙ,／μｙ＇）,ｙ（０,ε,μ）＝Ａ（ε,μ）,ｙ＇（０,ε,μ）＝Ｂ（ε,μ）当ε＝０（μ＾ｋ）,ｋ≥３时的双重边界层现象,通过引进不同量级的伸长变量,得到解的一致有效的渐近展形式。     

Comparison between Minimax and GLS Estimators in Linear Regression Model with Ellipsoid Restrictions

对于线性回归模型Ｙ＝Ｘβ＋ε,ε～（０,σ２Ｗ）,其中σ２＞０,Ｗ为正定矩阵．当未知参数β受到椭球约束时,文中分别在矩阵均方误和加权均方误意义下比较了β的Ｍｉｎｉｍａｘ估计（ＭＩＬＥ）与广义最小二乘估计（ＧＬＳＥ）之差异,并分别导出了在此两种意义下ＭＩＬＥ优于ＧＬＳＥ的充分必要条件．     

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.     

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     

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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Brief Introduction to “Journal of Jilin University( Science Edition) ”

<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 Peoples 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