关于复合加密方法的注记

对于给定的正整数Ａ和Ｂ,方程Ａｘ＋Ｂｙ＝Ｃ（△）有无穷多个解ｘ＝ｘ０＋Ｂｄｔ,ｙ＝ｙ０－Ａｄｔ,ｔ∈Ｉ,（＊）其中（ｘ０,ｙ０）是方程的一个特解,ｄ＝ｇｃｄ（Ａ,Ｂ）。对于任何长度为Ｂｄ的半开区间Ｉ,方程（△）的满足ｘ∈Ｉ的解是唯一的,利用这种唯一性,我们提出了一个设计复合加密方法的方案,并且讨论了ＤＥＳ型复合加密公钥体制．     

反函数的导数定理的注记

给出反函数的导数定理的改进形式；若ｆ（ｘ），ｘ∈（ａ，ｂ）与ψ（ｙ），ｙ∈（Ａ，Ｂ）互为反函数，ｘ０∈（ａ，ｂ），ｙｐ＝（ｆ９ｘ０），ψ（ｙ）点ｙ０处可导且ψ（ｙ０）≠０，ｆ（ｘ）在点ｘ０处可导，且ｆ’（ｘ０）＝１／ψ（ｙ０），并说明，ｆ（ｘ）在点ｘ０处连续一条件不可去掉。     

二元函数的微积分基本定理

从二元函数的面导数出发定义原函数和不定积分，研究了它们的性质．证明了：（１）若ｆ（ｘ，ｆｙ）有原函数，则有一族原函数且任意两个原函数相差ｋ（ｘ，ｙ）＝Ｃ（Ｘ）＋Ｄ（ｙ）＋Ｅ，其中Ｃ（ｘ），Ｄ（ｙ）为一元函数，Ｅ为常数；（２）若ｆ（ｘ，ｙ）在闭区间［Ａ，Ｂ］Ｒ２上连续，Ｚ＝（ｘ，ｙ）∈［Ａ，Ｂ］，则Φ（ｘ，ｙ）＝ｆ（ｓ，ｔ）ｄｓｄｔ在（ｘ，ｙ）可导且Φ’ｘｙ＝ｆ（ｘ，ｙ）；（３）若ｆ（ｘ，ｙ）在［Ａ，Ｂ］上连续，Ｆ（ｘ，ｙ）为其一个原函数，则ｆ（ｘ，ｙ）ｄｘｄｙ＝Ｆ（［Ａ，Ｂ］）．     

LaSalle矩阵不等式的加强

设Ａ是ｎｘｎ 非奇异矩阵,Ｂ是ｎｘｎ 对称矩阵,且Ｇ＝ － （ＡＴＢ＋ ＢＡ） 正定,那么对任意ｘ,ｙ ∈Ｒｎ,且ｘ ≠０,有（Ｂｘ ＋ ｙ）ＴＧ－ １（Ｂｘ ＋ ｙ） ≥〔ｘＴ（ＡＴ）－ １（Ｂｘ ＋ ｙ）〕２ｘＴ（ＡＴ）－ １ＧＡ－ １ｘ ≥－ ２ｙＴＡＴｘ     

两分子饱和反应系统的极限环的存在性与唯一性

陈兰荪等在第二届中国生物数学学术会议上提出了生物动力学系统中研究的１１个问题。作者所研究的是第１１个问题，生物化学中两分子饱和反应。其数学模型为ｘ＝Ｊ＿１（１＋ｘ＋ｙ＋Ａｘ￣２）－ｘ（１＋ｘ＋ｙ＋Ａｘ￣２）－Ｂｘｙ；ｙ＝Ｊ＿２（１＋ｘ＋ｙ＋Ａｘ￣２）－Ｂｘｙ．其中：Ｊ＿１、Ｊ＿２、Ａ、Ｂ为非负常数，当Ｊ＿１－３Ｊ＿２＜－［１＋Ｂｘ＋（Ｂ＋１）ｙ］／（１＋Ａｘ）时，该模型在第一象限内至少存在一个极限环；当Ｊ＿１＜Ｊ．ｘ＜ｙ，Ｂ＞ｌ且ｘ＞ａ时，该模型在第一象限内存在唯一的极限环。其中ａ＜０为方程ｐ（ｘ＝）＝０的最大负实根．     

欧拉方程的算子算法

在算子Ｂ＝ｘ．ｄ／ｄｘ作用下,欧拉方程ｘｎｄｎｙ／ｄｘｎ＋Ｐ１ｘ＾ｎ－１ｄｎ－１／ｄｘ＾ｎ－１＋．．．＋Ｐｎ－１ｘｄｙ／ｄｘ＋Ｐｎｙ＝ｆ（ｘ）,其中Ｐ１,Ｐ２,．．．,Ｐｎ为常数）,可化为：（Ａ＾ｎＢ＋Ｐ１Ａ＾ｎ－１Ｂ＋．．．＋Ａ＾０Ｂ）ｙ＝ｆ（ｘ）。并简记为Ｌ（Ｂ）ｙ＝ｆ（ｘ）,把Ｂ待定系数ｋ,则Ｌ（Ｂ）＝０即为欧拉方程的特征方程,从而可求出齐次方程的通解ｙＨ,再根据Ｌ（Ｂ）的逆算子性质求欧拉方程的特解ｙｐ＝１／Ｌ（Ｂ）ｆ（ｘ）,便求得欧拉方程的通解：ｙ＝ｙＨ＋ｙｐ。     

一类三次Kolmogorov系统的定性分析

研究了一类三次Ｋｏｌｍｏｇｏｒｏｖ系统ｘ＝ｘ（Ａ０＋Ａ１ｘ－Ａ３ｘ＾３＋Ａ２ｙ），ｙｄ＝ｄｙ（－１＋ｘ＾２－６（（＊）；ｘ＝ｘ（Ａ０＋Ａ２ｘ－Ａ３ｘ＾２－Ａ２ｙ），ｙ＝ｙ（－１＋ｘ＾２－ｙ）（＊＊）。得到：（１）Ａ０＞Ａ２，Ａ２＜Ａ３＜Ａ１时，系统（＊）在第一象限内不存在极限环；（２）当Ａ３＞Ａ２，Ａ０＋Ａ２＞１／２时，系统（＊＊）在第一象限内是全局稳定性的。     

一类2阶边值问题的分歧点

考虑如下的２阶非线性方程的边值问题：ｘ″＝λ（Ａｘ＋Ｂｘ′）＋ｆ（ｔ，ｘ，ｘ′，λ）（０≤ｔ≤１），ｘ（０）＝ｘ（ｌ）＝０．在关于Ａ，Ｂ，ｆ的一组条件下，利用Ｋｒａｓｎｏｓｅｌｓｋｉｉ定理证明了上述问题存在分歧点。     

一个Riccati方程解的渐近性态

该文在ｐ（ｘ）∈ｃ’「ｘ０＋∞），ｑ（ｘ）∈ｃ「ｘ０，＋∞），ｘｃ〉０且０≤１／２ｐ’（ｘ）－１／４ｐ＾２（ｘ）＋ｑ（ｘ）≤１／４ｘ＾２的条件下，研究下列Ｒｉｃｃａｔｉ方程的解的极限ｌｉｍｘ→＋∞ｙ（ｘ），ｌｉｍｘ→＋∞，ｌｉｍｚ→＋∞ｙ’（ｘ）／ｙ（ｘ），由此得到了此类方程的任一非零解存在渐近线的充分必要条件。     

一类阿贝尔方程极限环的几个判定准则

当ｎ次微分系统ｘ′＝λｘ－ｙ＋Ｐｎ（ｘ,ｙ）,ｙ′＝ｘ＋λｙ＋Ｑｎ（ｘ,ｙ）（ｎ≥２）化为Ａｂｅｌ方程ｄｚ／ｄθ＝Ａ（θ）ｚ３＋Ｂ（θ）ｚ２＋Ｃ（θ）ｚ后,利用λＡ（θ）的符号给出了判定Ａｂｅｌ方程极限环的几个准则：（１）当λＡ（θ）≥０且ｎ为偶数时方程无极限环;（２）若λＡ（θ）≤０时,则方程存在唯一极限环;（３）若λＡ（θ）≥０且ｎ为奇数,则方程最多只有两个极限环．     

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