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1.
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   

2.
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   

3.
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   

4.
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   

5.
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   

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   

7.
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  相似文献   

8.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

9.
<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   

10.
11.
<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  相似文献   

12.
Canonical Wnt/β-catenin pathway plays a central role in development, homeostasis, as well as tumorigenesis. The regulation of the pathway involves various and complicated mechanisms, including the extracellular, intracellular and endonuclear regulation. As the key component of the pathway, the Lefl/Tcfs-β-catenin complex is also the key target of regulation in the nucleus. In the current review, we are going to summarize the regulators in the nucleus which can modify the transcrip- tional activity of the Wnt/β-catenin pathway.  相似文献   

13.
Preface     
正The standard model(SM)in particle physics has been successfully tested by the present experimental observations.The SM consists of electroweak unification theory and quantum chromodynamics(QCD)theory with light quarks(u;d;s)and heavy quarks(c;b;t)as its fundamental components.Usually,these quarks are named as the light flavor and the heavy flavor.In addition to quarks,there are intermediate gauge bosons and gluons for mediating the  相似文献   

14.
《科学通报(英文版)》2014,(22):I0001-I0004
正May 26,2014,Beijing Science is a human enterprise in the pursuit of knowledge.The scientific revolution that occurred in the 17th Century initiated the advances of modern science.The scientific knowledge system created by human beings,the tremendous productivity brought about by science,and the spirit,methodologies and norms formulated in scientific practice since the 17th Century have long become essential elements of modern civilization.Today’s world is characterized  相似文献   

15.
利用BP神经网络自适应性强的优势,将动量BP神经网络应用于高压电力计量系统故障诊断中.对计量系统的7个运行参数提取故障信息作为网络的输入值,以4位二进制数表示正常情况和7种主要故障类型,用采集得到的样本对网络进行训练及测试,结果表明,动量BP神经网络模型对高压电力计量系统故障有很好的辨识和诊断效果.  相似文献   

16.
为了采用全有限差分方法进行涡轮气热弹耦合计算,研究了固体弹性应力场计算的物理模型,给出了任意曲线坐标系下的控制方程.同时研究了定常问题的有限差分求解方法和边界条件的给定,编制了定常问题的应力场求解程序;并通过对具有解析解的受集中载荷的悬臂梁和一端受径向集中力的曲梁进行数值计算来验证该固体弹性应力场的求解方法.结果表明,边界条件的二阶精度处理的格式所得结果与解析解数据吻合得较好,而一阶精度格式结果与解析解有较大的误差.  相似文献   

17.
作者在文[11中对单项式代数进行了推广,并定义了一类新的代数-无交换关系代数.本文证明了控制维数大于等于2的右Artin代数∧是Nakayama,代数当且仅当∧是无交换关系代数,从而在此类代数上证明了Nakayama猜想和AuslanderReiten猜想.  相似文献   

18.
We present two recent methods, called UTAGMS and GRIP, from the viewpoint of robust ranking of multicriteria alternatives. In these methods, the preference information provided by a single or multiple Decision Makers (DMs) is composed of holistic judgements of some selected alternatives, called reference alternatives. The judgements express pairwise comparisons of some reference alternatives (in UTAGMS), and comparisons of selected pairs of reference alternatives from the viewpoint of intensity of preference (in GRIP). Ordinal regression is used to find additive value functions compatible with this preference information. The whole set of compatible value functions is then used in Linear Programming (LP) to calculate a necessary and possible weak preference relations in the set of all alternatives, and in the set of all pairs of alternatives. While the necessary relation is true for all compatible value functions, the possible relation is true for at least one compatible value function. The necessary relation is a partial preorder and the possible relation is a complete and negatively transitive relation. The necessary relations show consequences of the given preference information which are robust because “always true”. We illustrate this methodology with an example.  相似文献   

19.
In contrast to ab initio methods like first principles that handle small-scale systems,a multiband k·p method is more efficient for modeling low dimensional systems with a big compilation of atoms like quantum dots(QDs).Electronic structures are obtained only at low k but sufficient for simulating optoelectronic properties.The Fourier transform-based k·p method formulates both Hamiltonian matrix and envelope functions and thus solves the k·p  相似文献   

20.
利用大量水质资料,结合水文地质条件对河南东部地下水主要指标空间分布特征、相互关系及水文地球化学特征进行了系统分析研究,根据有关水质指标相互关系及其与阳离子比例系数的关系特征对地下水进行了水质分层.首次发现了豫东平原地下深层软水阳离子比例系数(NACA)与总硬度(Z)相关关系方程为NACA=a·Z-b,且b值为1.5;并采用碳酸平衡作用、同离子效应理论推导出了上述关系式(包括b值为1.5);结合阳离子交替吸附作用形成软水的三个前提条件分析、钻孔地层资料验证等,进一步论证了河南东部深层地下水自然软化模式遵循"碳酸平衡作用"模式.  相似文献   

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