一类互惠模型正解的存在性

利用正的紧线性微分算子的谱性质和锥映象不动点指标,结合极值原理和上下解方法,研究了具有饱和项的Volterra-Lotka互惠模型的平衡态方程,得到了具有饱和项的互惠模型正解存在的充分条件.     

一类捕食模型正解的存在性分析

研究了一类捕食模型的平衡态方程,通过利用正的紧线性微分算子的谱性质和锥映像不动点指标, 结合极值原理,上下解方法, 得到了正解存在的充分条件.     

一类无搅拌Chemostat模型平衡态正解存在性与数值模拟

 讨论一类含有Beddington-DeAngelis反应功能函数的Chemostat非单链生态模型平衡态正解的存在性,利用特征值比较原理得到正解存在的必要条件。利用度理论、锥映射不动点指数、微分算子的谱半径理论得到正解存在的充分条件。应用MATLAB软件进行数值模拟,验证了正解的存在性。     

一类带饱和项互惠模型平衡态正解的存在性

研究了一类两个物种同时带有饱和项的互惠模型在第一边界值条件下的平衡态正解的存在性．首先用单调解的方法给出了此解的先验估计，然后利用局部分歧理论研究了在λ1-c〈a〈λ1和a〉λ1两种情况下模型分别在两个半平凡解上出现的局部分歧现象，并证明了分别在分歧点（β，0，θβ）和（b＇，θa，0）附近存在正解；最后利用全局分歧理论研究了其整体分歧，从而证明了这两种情况下模型存在平衡态正解．     

具有饱和项和毒素影响的互惠模型的周期解

利用重合度拓展定理研究一类具有饱和项和毒素影响的互惠模型的周期正解问题.     

具分数微分算子的分数阶微分方程边值问题正解的存在性

利用Leggett-Williams不动点定理和锥上不动点定理,研究一类具有分数线性微分算子的分数阶微分方程边值问题,得到了该边值问题至少1个正解和至少3个正解的存在性定理.     

一类带饱和项互惠模型平衡态解的稳定性

文章研究了一类两个物种同时带饱和项的互惠模型在第一边界值条件下的平衡态解的稳定性.首先给出了此类模型的平衡态方程解的情况,然后运用线性算子的特征值理论讨论了其平凡解、半平凡解的稳定性,最后运用扰动理论和分歧解的稳定性理论分别得到了λ1-c〈a〈λ1和α〈λ1在两种情况下正解分支的稳定性情况．     

一类非线性分数阶微分方程的正解

针对具有积分边值条件的分数阶微分方程正解的问题,利用算子不动点理论,结合迭代逼近的思想,给出一类非线性项带参数且具有积分边值条件的分数阶微分方程正解的存在唯一性,并通过构造迭代序列来逼近方程的正解;利用一类特殊算子方程正解的性质,结合所讨论方程格林函数的性质,给出方程正解依赖于参数的一些性质。结果表明,利用算子不动点理论讨论非线性项带参数的分数阶微分方程边值问题正解的存在唯一性是可行的。     

一类奇异自伴微分算子的本质谱

考虑一类微分算式中具有对数函数系数的自伴微分算子，并主要通过构造奇异序列的方法得到了一定条件下算子的本质谱．与Euler微分算子的本质谱进行比较，可见对数函数系数对算子的谱产生了很大影响．     

一类非自治n种群互惠系统的周期正解

研究了一类具有周期系数互惠的n种群微分系统.在适当的Banach空间中引入算子,将微分系统化为等价的算子方程;利用Arzela-Ascoli及重合度的同伦不变性质,证明了所引入的算子满足重合度延拓定理的条件,从而证明了系统周期解的存在性,并给出解的估计.     

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