参数多目标最优化是最优值函数的一些性质

文章讨论了参数多目标规划问题：Ｐ（ｕ）：ｍｉｎ ｆ（ｘ，ｕ）ｓ．ｔ．ｘ∈Ｒ（ｕ）基最优多值函数Ｈ（ｕ）Ｅ［ｆ（ｘ，ｕ）│ｘ∈Ｒ（ｕ）的Ｋ－凸性及其它一些性质。     

波动方程的柯西问题存在时间周期解的充要条件

本文证明三维齐次波动方程的柯西问题Ｕｕ－△ｕ＝０，ｔ〉０，ｘ∈Ｒ＾３，ｔ＝０：ｕ＝ψ（ｘ），ｕｔ＝ψ（ｘ），ｘ∈Ｒ＾３。存在的时间周期解的一个充要条件是初值（ψ，ψ）满足一类积分平均型条件。     

一类双曲型方程解的爆破（Blow—up）现象

ＬａｉＳｈａｏｙｏｎｇ＆ＭｕＣｈｕｎｌａｉ（ＡｐｐｌＭａｔｈ－ＪＣＶ,１９９７,１２Ｂ：３２１）研究了在ｆ（ｘ）,ｇ（ｘ）,Ｇ（ｕ）满足一定条件下,如下方程ｕｔ－Δｕ＝εＧ（ｕ）,ｔ≥０,ｘ∈Ｒ３,ε＞０充分小,ｕ（ｔ,ｘ）＝ｆ（ｘ）,ｕｔ（ｔ,ｘ）＝ｇ（ｘ）,ｘ∈Ｒ３｛解的渐近理论及应用．且在假设ｆ（ｘ）≡０,ｇ（ｘ）及Ｇ（ｕ）满足一定条件下得到了以上双曲型问题整体解的非存在性．因此,本文的工作可以看成是ＬａｉＳｈａｏｙｏｎｇ＆ＭｕＣｈｕｎｌａｉ工作的继续．     

椭圆型方程整体解不存在性的两个判别准则

通过构造适当的的比较函数和利用比较原理，建立了Ｒ＾ｎ上一类半线性椭型方程的两类正解ｕ（ｘ）不存在性的两个判别准则：１．当│ｘ│→∞时，ｕ（ｘ）衰减到０，（ｂ）存在常数ｃ〉０，使ｕ（ｘ）≥ｃ，ｘ∈Ｒ＾ｎ，推广了Ｈ．Ｕｓａｍｉ的有关结果。通过例子说明文中的判别条件几乎是充要的。     

一类约束极小问题的几个结果

研究了与等周不等式有关的约束极小问题：Ｉｔ＝ｉｎｆＱ（ｕ＋ｔψ）＝１,ｕ∈Ｈ１０（Ω,Ｒ３）∫Ω｜ｕ｜２ｄｘｄｙ,其中,Ω为Ｒ２中的有界区域,Ｑ（ｖ）＝∫Ωｖ（ｖｘ∧ｖｙ）ｄｘｄｙ．证明了如下结论：１）对于ψ∈Ｈ１０（Ω,Ｒ３）,若ψｘ∧ψｙ０,且ψ∈Ｃ１,１０（Ω,Ｒ３）,则Ｉｔ→Ｓ（当ｔ→０时）;２）设ｕｔ是Ｉｔ的极小可达函数,则存在某一ｘ０∈Ω,使得｜ｕｔ｜２Ｓδｘ０（当ｔ→０时）（在测度意义下）,这里Ｓ＝ｉｎｆ∫Ｒ２｜ｕ｜２ｄｘｄｙｕ∈Ｈ１０（Ｒ２,Ｒ３）,Ｑ（ｕ）＝１｛｝     

Feedback Linearization H_∞ Control and Its Applicationto Excitation Systems

Ｉｎｔｒｏｄｕｃｔｉｏｎ　　Ｃｏｎｓｉｄｅｒｔｈｅｆｏｌｌｏｗｉｎｇｎｏｎｌｉｎｅａｒｕｎｃｅｒｔａｉｎｓｙｓｔｅｍ：·ｘ＝ｆ（ｘ）＋ｇ１（ｘ）ｗ＋ｇ２（ｘ）ｕ,ｚ＝ｈ（ｘ）（１）ｗｈｅｒｅｘ∈Ｒｎ,ｕ∈Ｒｍ,ｗ∈Ｒｐ,ｚ∈Ｒｓａｒｅｓｔａｔｅ,ｃｏｎｔｒｏｌ,ｄｉｓｔｕｒｂａｎｃｅａｎｄｒｅｇｕｌａｔｉｏｎｏｕｔｐｕｔ,ｒｅｓｐｅｃｔｉｖｅｌｙ．ｆ,ｇ１,ｇ２ａｎｄｈ（ｘ）ａｒｅｓｍｏｏｔｈｍａｐｐｉｎｇｗｉｔｈｓｕｉｔａｂｌｅｄｉｍｅｎｓｉｏｎｓ,ａｎｄｆ（０）＝０,ｈ（０）＝０．Ｔｈｅｎｏ…     

环上非线性椭圆型方程非径向正解的存在性

我们研究了非线性椭圆型方程Δｕ＋ｇ│ｘ│ｆ（ｕ）＝０ｉｎΩＲ０Ｒ１ｕ＝０ ｏｎ δΩＲ０Ｒ１０〈Ｒ０〈Ｒ１正在非轴对称解的存在性。灾里ΩＲ０４１＝｛ｘ∈Ｒ＾ｎ：Ｒ０〈│ｘ│〈Ｒ１｝是Ｒ＾ｎ中的一个环，ｎ≥２。当ｆ满足一定条件时，那么我们可以用Ｎｅｈａｒｉ技巧证明存在Ｒ＾＊∈（Ｒ０，Ｒ１）使得对任意Ｒ∈（Ｒ０，Ｒ＾＊），在ΩＲ０Ｒ上方程有一个非轴对称解。     

素环的反自同构与交换性

设Ｒ是特征不等于２的素环，Ｔ为Ｒ的非对合（Ｔ￣２≠１）反自同构，若Ｒ满足如下条件之一，则Ｒ为交换环：（ｉ）ｘ￣２ｘ￣Ｔ－ｘ￣Ｔｘ￣２∈Ｚ（Ｒ），ｘ∈Ｒ；（ｉｉ）ｘ￣２ｘ￣Ｔ－ｘｘ￣Ｔｘ∈Ｚ（Ｒ），ｘ∈Ｒ．     

关于Cauchy问题解爆破的一个条件

关于Ｃａｕｃｈｙ问题解爆破的一个条件曹镇潮（厦门大学数学系厦门３６１００５）在ＲＮ×Ｒ＋（Ｎ２）中考虑非线性双曲型方程的Ｃａｕｃｈｙ问题ｕｔ－△ｕ＝｜ｕ｜ｐ－１ｕ，（ｘ，ｔ）∈ＲＮ×（０，Ｔ）ｕ（ｘ，０）＝ｇ（ｘ），ｘ∈ＲＮｕｔ（ｘ，０）＝ｈ（ｘ）...     

凸度量空间上的一个不动点定理

设Ｘ为具有性质（Ｃ）和（Ｐ）的凸度量空间，Ｋ是Ｘ的非空凸子集，ＴＫ→２Ｘ使得ｘ→ｄ（ｘ，Ｔｘ）是１．ｓ．ｃ．若ｉｎｆ｛ｄ（ｘ，Ｔｘ）｜ｘ∈Ｋ｝＝０，且ｘ，ｙ∈Ｋ，λ∈［０，１］，ｕ＝Ｗ（ｘ，ｙ，λ）有ｄ（ｕ，Ｔｕ）≤Φ（ｍａｘ｛ｄ（ｘ，Ｔｘ），ｄ（ｙ，Ｔｙ）｝）．这里ΦＲ＋→Ｒ＋满足条件Φ（０）＝０，在０的右边不减和连续，则Ｔ在Ｋ上有不动点．它推广了Ｔ．Ｈ．Ｃｈａｎｇ和Ｃ．Ｌ．Ｙｅｎ（１９８９）在Ｂａｎａｃｈ空间中的结果     

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