一类非线性薛定谔方程的孤子解

 研究了具有V(x,t)=f₁(t)x+f₂(t)x²形式的外部势的非线性薛定谔方程的单一孤立子解.结果表明:当孤立子的中心满足带有势V(x,t)的牛顿方程,孤立子的内部结构由"体固定"坐标系决定.孤立子的结构与f₁(t)无关.若f₂(t)与t无关,孤立子是固定的.原则上,若f₂(t)剧烈变化,则孤立子将扩散.但数值计算表明,在一定条件下,孤立子还是经得起f₂(t)的剧烈变化.     

风机荷载作用下频率比对砂土动力响应的影响

海上风机在运行过程中风荷载与波浪荷载频率耦合作用对土体动力特性的影响不容忽略,为了探究这种影响,采用多向循环动单剪系统（VDDCSS）对砂土进行了一系列试验研究,分析了双向剪切频率比f_r对砂土动应变、动孔压比以及动强度的影响。试验结果表明：剪应变发展受双向频率耦合及应力组合效应的影响。循环应力比（C_SR）为0.15时,双向频率耦合效应大于应力组合作用;随着应力水平的增加（C_SR = 0.20或0.25）,频率耦合效应和应力组合作用均得到了加强。在低应力水平时,破坏试样的孔压曲线呈“上凹型”且频率比对试样孔压发展影响不大。而随着应力水平增加（C_SR = 0.20或0.25）,孔压最终值u_max随之增大。除f_r = 1.00与10.00对应试样外,土体动强度随f_r与C_SR值增大而减少。f_r= 5.00 对应试样应变大、孔压值高、强度低的原因与此比值下土体受双向频率耦合与应力组合的叠加效果增强有关。     

对数凹函数熵的低维Busemann-Petty问题

引入对数凹函数熵的Busemann-Petty问题,即对于2个Rⁿ上的偶的对数凹函数f和g, 且f和g具有正的、有限的积分,假设∫_Rⁿ∩Hf(x)dx≤_Rⁿ∩Hg(x)dx对于任意i维子空间H均成立,是否能够得到Ent(f)≥Ent(g).得到了该问题的部分解答, 为解决凸体上的低维Busemann-Petty问题提供了一种新的途径.     

Hilbert空间中两个K-框架的算子组合

讨论了Hilbert空间中两个K-框架{f_i}^∞_i=1与{g_i}^∞_i=1通过算子作用再求和后得到的序列{T₁ f_i+T₂g_i}^∞_i=1成为K-框架与紧K-框架的一系列等价条件,所得结果推广与修正了已有结果.     

线性交换子的加权估计

 多线性交换子T_b(f)(x)=∫_Rⁿ∏_i=1^m(b_i(x)-b_i(y))k(x,y)f(y)dy在L^p(Rⁿ)(1K是一个标准的Calderón-Zygmund核.主要研究交换子Mf(x)=sup_x∈Q∫_Q|f(y)|dy,其中f∈L_loc(Rⁿ),x∈Rⁿ,Q是任何包含x的方体,并用Sharp极大估计得到了该多线性交换子在Herz空间的一个加权有界性.     

具强迫项的中立型差分方程的振动性和渐进性

 使用不等式的某些技巧,获得了如下具强迫项的中立型差分方程Δ(y_n+y_n-τ)+Q_nG(y_n-σ)=f_nn∈N的所有解振动或当n→∞时趋于零的充分条件.还获得了如下的中立型差分方程Δ(y_n-y_n-τ)+Q_nG(y_n-σ)=0 n∈N的所有解振动的充分条件.     

CRU数据集在黑龙江省ET0计算中的应用

针对我国参考作物蒸发蒸腾量(ET₀)计算中存在的气象数据不易获取、现有作物需水量数据空间分辨率较低等问题,以黑龙江省为例,基于10 min分辨率的CRU CL 2.0数据集,采用FAO Penman-Monteith公式建立了适于计算区域ET₀的栅格模型,并应用黑龙江省14个气象站的实测气象数据对该模型计算成果进行了验证。结果表明:采用CRU CL 2.0数据计算区域ET₀是可行的,其计算结果与应用实测气象数据计算所得的ET₀符合较好,不仅可以细化我国ET₀和作物需水量研究成果,也为气象资料缺乏情况下的ET₀计算供了一种新的计算模式。     

一类Rn上奇异非线性双调和方程正整解的存在性及性质

 以Schauder-Tychonoff不动点定理为工具,建立了一类Rⁿ上奇异非线性双调和方程Δ²_u=f(|x|,u,|▽u|)u^-β(n≥3,β>0)正的径向对称整体解的存在性定理,并给出了解的有关性质.     

CH2(X3B1)分子的结构与解析势能函数

 运用密度泛函理论(DFT)的B3LYP方法在6-311++G^**水平上,对基态CH₂分子的结构进行了优化计算,得到CH₂分子的稳定结构为C_2v构型,电子态为X³B₁,平衡核间距R_CH=0.1072nm、离解能D_e=8.034eV,用多体项展式理论推导了基态CH₂分子的解析势能函数,其等值势能图准确再现了基态CH₂分子的结构特征及其势阱深度与位置.     

基于改进概率积分法的倾斜条带状工作面开采沉陷预计研究

常规概率积分法适用于水平和近水平煤层开采沉陷预计,对倾斜煤层的开采沉陷预计存在较大误差,为此,借鉴变步长数值积分的思想,提出倾斜条带状工作面开采沉陷预计的改进概率积分法,设计了新的计算模型;具体做法是：将工作面在埋深方向用二分法划分为多个子工作面,从而将倾斜工作面的开采沉陷预计转化为多个水平子工作面的开采沉陷预计;对细分级数f ,进行 f轮计算;对第i(i=1,2,...,f-1) 轮计算,工作面被等分为2ⁱ 个子工作面,进行 2ⁱ次迭代计算;第 i轮迭代计算后,再将每个子工作面在深度方向进行二分,继而进行下轮迭代计算,重复进行,直到前后两轮计算结果差值的均值和方差均在目标范围内。证明了该算法的收敛性;算法分析表及应用实例明,该方法消除了倾角和平均深度对倾斜煤层开采沉陷的误差,计算模型更加科学,计算结果更可信,适用于任意倾斜条带状煤层和非煤地下矿较规整采场开采沉陷预计,以及自然崩落法矿岩接触面模拟。     

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