双等比数列

利用取整符号并结合构造方法给出了双等比数列的定义、通项公式及前 n项和公式 ,并进而推广给出 m等比数列的定义、通项公式及前 n项和的公式     

垂直介质分界面的入射光反射前后位相关系的讨论

一般光学教材在处理光线垂直界面入射而发生反射的问题时,用菲涅尔公式中的正负符号简单地表示入射光垂直于入射面的的电矢量与平行于入射面的电矢量反射前后位相的变化。然而,这种表示是不完全的。本文讨论了此问题的解决方法。     

自然数n次幂的求和公式及其因式分解的Matlab求解

应用待定系数法研究了自然数n次幂的求和公式及其因式分解的计算机符号推导,并给出线性方程组中系数矩阵所对应的n=1-16的条件数,同时将该方法应用到所有的自然数的多项式函数求和公式及其因式分解.     

非正入射条件下的光栅衍射实验

分析了现行光栅实验中将平行光斜入射作为正入射条件处理引起的误差。验证了当入射角α<2·5°时,在实验精度范围用正入射公式处理是可行的,但当入射角较大时则须用斜入射公式处理。     

子自相似集合的Hausdorff维数

应用符号动力系统 ,讨论了由Falconer定义的子自相似集的Hausdorff维数的连续性 ,得到了子自相似集的Hausdorff维数和盒维数的新公式     

一种改进的手写数学公式符号识别算法

针对手写数学公式符号的特殊性提出一种改进的公式符号识别算法,利用外接矩形技术来切分公式符号,利用改进的BP神经网络算法进行手写数学公式符号识别,实验证明,改进后的公式符号识别算法提高收敛速度和识别的效率.     

斜入射时网格法在耗损材料参数匹配机理研究中的应用

通过平面波反射系数公式给出了电磁波斜入射时单层电磁损耗材料反射系数公式,用网格法对影响反射系数的参数进行了分组讨论与优化,利用计算机对斜入射时耗损材料参数匹配进行了辅助设计,优化结果有利于实际材料的设计和应用.     

基于组合策略的印刷公式符号切分方法

对公式符号切分这一公式识将符号分离与符号合并策略相结合,提取公式符号的方法,对具有包含关系的符号进行分离操作,而对由多个连通部件构成的符号进行合并处理.实验表明,该方法能够较好地适应公式特点,具有较高的准确性.     

电磁波在导体中传播的几个问题的探讨

由边值关系出发,讨论了折射波的传播方向、波长、能量和穿透深度,得出电磁波在导体面上折射时,波长会变短;推导了以任意入射角入射的菲涅耳公式和反射系数,根据该组公式分析了以自然光入射的反射波与折射波的偏振特性。     

趋肤效应的理论研究与解析计算

从麦克斯韦方程出发,给出电磁波垂直入射到良导体和欠良导体时的电场表达式;应用菲涅尔公式给出电磁波垂直入射到良导体和欠良导体两类材料的趋肤效应的理论解释,推导出趋肤深度的表达式;数值计算结果与现有公式得出的数据符合程度较高．     

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