对称加密算法AES和DES的差分错误分析

分析对称加密算法AES和DES对差分错误分析的安全性.描述了一种针对AES加密算法的差分错误分析方法,通过软件模拟成功恢复根密钥.实验结果表明,只需20次左右的错误注入就能实现AES差分错误分析.提出一种新的DES差分错误分析方法,该方法与AES差分错误分析在原理上类似,软件模拟结果表明破解DES需要的错误注入次数更多.因此无任何防护手段的AES和DES加密算法很容易受到差分错误分析的攻击.最后提出引入错误侦测机制能有效抵御此类攻击.     

汉式英语产生原因浅析

人们在学习外语的过程中总是不可避免地受到母语的思维方式和表达习惯的影响。汉式英语就是中国人在学习英语时，受汉语的干扰而说出或写出的不合英语语法和表达习惯的畸形英语。对常见的汉式英语错误进行了分类列举，并分析了产生错误的原因，帮助英语学习者在学习过程中有效避免此类错误的发生，从而学说标准、地道的英语。     

再论三要素法的适用对象

先讨论了文献[1]中关于用三要素法求解电路的一个例题及结论，指出其错误，并分析了错误产生的原因，得出三要素法不仅适合电容电压和电感电流的求解，也适合电阻电流和电压的求解．最后就如何避免学生出现此类问题对三要素法的教学方法作了初步的探讨．     

艺术类学生英语习作中常见错误探析

从词法和句法两方面分析了艺术类学生英语习作中的常见错误类型及成因，并对此提出了解决措施，以减少此类错误的发生。     

巧用函数、慎用导数解决数列问题

数列是离散型函数,是特殊的函数,所以对于一些数列问题,学生会尝试用函数的思想来解决,往往会有意想不到的效果。对于数列中的单调性问题,学生经常会想到利用导数求解。但是由于没有深刻认识到数列是离散型函数,在解题过程中经常会犯一些错误。本文旨在引导学生认识到错误产生的原因并学会解决此类问题。     

石化公司中有功电能表计量损失分析

三相四线三元件电能表在石化企业中的应用也越来越广泛,具有诸多优点,但此类有功电能表仍所存在计量损失等问题。对此,分析了由于电流互感器接线错误而导致的计量损失问题,并通过理论分析,获取了错误情况时的接线和电能的表达式,进一步阐述清楚计量损伤的原因,为解决此类问题提供参考。     

英语专业翻译测试的探索与反思

在英语专业的翻译课上,本研究将期末测试从传统的试卷考试调整为期末翻译项目。从翻译项目的完成情况来看,英语专业的学生在翻译时容易犯特定类型的错误。为了避免此类错误的出现,本研究分别从三个方面探讨了造成此类错误的原因,即学生的学习习惯、高校教师的工作现状以及学科的课程设置。根据以上原因,本研究分别提出相关建议。     

浅析高职高专非英语专业学生翻译常犯的错误

本文基于笔者多年实践教学经验,描述高职高专非英语专业学生在翻译句子和做命题作文时常犯的语法、词汇、句法、语序和思维方式等方面的错误;同时试着从语言学,文化差异等方面简单分析造成此类错误的的原因;最后提出笔者个人对此类问题的建议。     

礼貌、礼貌语言与“文化错误”

本文从礼貌以及礼貌语言的两个方面入手,阐述了某些中国人在说英语时,由于不了解异国的社会历史文化以及风俗习惯,在会话中易犯“文化错误”以及应该如何避免犯此类错误.     

环境监测硫化氢浓度曲线斜率偏低原因分析

通过技术上的分析查找及其他原因的分析,得出了环境监测硫化氢浓度曲线斜率偏低原因,保证不再出此类错误的措施。     

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

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.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

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-