关于对数螺线不变性之证明

在给出对数螺线及其相关定义之基础上，证明了与对数螺线相关的几种变换仍是对数螺线之间性质。     

极坐标法在高速铁路测量中的应用

高速铁路的测量工作是铁路施工中的重要环节,其工作成果的优劣直接关系到工程的进度和质量。本文主要讨论极坐标法在浙赣线电气化提速改造工程中的应用。     

应用极坐标证几何定理

本文应用极坐标法对平面几何的一些著名定理进行了证明。     

运用极坐标及方位角极坐标法进行施工测设

一般施工测量放线多采用经纬仪支架在主轴交点上放出构筑物的两条交线,然后转移到各主轴交点上,支架经纬仪在放出其他各条主轴线。对于比较复杂项目的放线就明显的露出了这种方法的原始性。当建筑物主体轴线交叉比较复杂时,用一般方法放线并不实用,支架经纬仪次数太多、偏差大;所以采用极坐标方法测量放线。对于提高精度,提高效率起到了一定作用。     

极坐标教学浅析

本文对解析几何中极坐标解题教学进行初步探讨,概括了运用极坐标培养学生能力的三种方法.     

各向异性磁介质毕奥-萨伐尔定律极坐标形式

给出磁各向异性介质中的毕奥-萨伐尔定律的极坐标形式.据此,可求出若干电流按曲线方程r=r(θ)分布的极坐标极点处的磁场,比用定律的笛卡儿坐标形式求解来得简便.     

极坐标的讲授

本文分析了极坐标与直角坐标不同的思维方式,强调了极坐标中很重要的三个圆,对二重积分化为二次积分时上下限的确定作了详细的讲解。     

极坐标法放样在施工测量中的应用

准确可靠的施工测量是保障执行公路、铁路设计意图的前提。施工测量通常包括导线的复测与加密,水准点的复测与增设,中线的恢复,路基、路面、桥涵和其他构造物的细部放样等。而中线的恢复,路基、路面、桥涵和其他构造物的细部放样工作是施工过程中工作量最大、任务最繁重的部分。在实际测量工作中递循"从整体到局部,由高级到低级,先控制后碎步"的原则,也就是在测区整体范围内选择一些有"控制"意义的点,首先把它们的坐标和高程用高精度的仪器和方法精确的测定出来,然后以这些点作为已知点来确定其他地面点的位置。     

重积分在极坐标变换下确定积分限的方法探究

本文研究了积分区域在极坐标变换下的变化规律,进而对直角坐标系下的重积分化成极坐标下的重积分后其累次积分限的确定给出了一种方法.     

定积分的几种特殊计算方法

<正> 定积分在很多实际问题中都有广泛的应用。我们在对定积分进行计算时,有的定积分如果按常规计算,不仅费时,而且还不易计算出结果。但利用级数、概率以及极坐标θ=θ(r)这些知识计算,就会绕过繁多的积分计算,使计算变得简单得多。现举例说明如下:     

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.     

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     

Call for Papers

<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     

Journal of Donghua University ( English Edition) Contents of Volume 31

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