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1.
在椭圆曲线公钥密码体制中,计算q元域Fq上椭圆曲线有理点的数目是至关重要的,这里q为素数p的幂.一个公认有效的计算有理点数目的Schoof算法需要用到有限域Fp2的原根.设n是一个正整数,F=Fqn为q元域K=Fq的n次扩张,α是F中的任意元,NF/K(α)是α在K上的范函数.用初等而简洁的方法,得到了α是F的原根的几个充分必要条件,并由此给出了由K的原根求Fq2的原根的一个算法.  相似文献   

2.
假设E是由方程y^2-y=x^3--x定义的椭圆曲线,Ez是E的Neron模型.本文证明了Steinberg符号{x,y^2)^2是K2(Ez)中的非扭元.  相似文献   

3.
设 K 为三次分圆域,E D[[lambda]] :y2=x3-24 3 3 D[lambda]为定义在 K 上的椭圆曲线, 其中 D 为 K 中无平方因子的代数整数, [lambda]属于Z . 邱德荣用一个非常复杂的函数给出了当 [lambda]=2,4 时E D[lambda] 的 Hecke L- 函数在点 1 处的值(除以椭圆周期) 恰被 3 n/2 -1 整除 的充要条件. 本文用加权图的语言给出了这个充要条件一个简单的组合论的刻画.  相似文献   

4.
椭圆曲线加密体制的双有限域算法及其FPGA实现   总被引:2,自引:0,他引:2  
提出一种支持椭圆曲线加密体制的双有限域算法。该算法可以同时完成素数域和二进制域上的运算,并且模数p和取模多项式可以任意选取。提出了椭圆曲线加密体制运算单元的设计方法,此运算单元可以同时完成素数域和二进制域上的所有运算,包括加法、减法、乘法、平方、求逆和除法。此外,描述了椭圆曲线加密体制的FPGA实现,最终的电路可以对任意长度密钥进行加密,并且支持素数域和二进制域上的任意椭圆曲线。  相似文献   

5.
本文首先构造了一个基于椭圆曲线的E1Gamal型广播多重数字签名方案,然后在其基础上我们设计了一个基于改进的椭圆曲线E1Gamal广播多重盲签名方案.这两个方案的安全性强、计算量小、效率高,从理论上分析能够防止系统攻击者的各种攻击.  相似文献   

6.
本文论及的空间E、F 和F_α(α∈(?))均为复数域上的拓扑线牲空间,ψ(F)为关于F 的一个基族。本文主要是讨论ψ-(K)拟线牲算子族A_α:E→F(α∈(?))的等度连续牲和按ψ∈Ψ(F)等度连续牲(见定理1和2)。同时,进一步讨论算子族中诸算子的象空间可以是不同的空间,即A_α:E→F_α(α∈(?))的情形,并有类似的结果(见定理3和4).  相似文献   

7.
一种素数域上的非超奇椭圆曲线构造方案   总被引:1,自引:0,他引:1  
对基域为素数域的非超奇椭圆曲线进行了研究,给出了构造素域上具有特定素数阶的非超奇椭圆曲线的一种算法,分析了算法时间复杂度.  相似文献   

8.
目的给出数值域非端点的一个刻画,并且给出GUSTAFSON K E等人编著的Numerical Range:The Field of Values of Linear Operators and Matrices(Springer-Verlay,1977)一书中定理1.5-2的另外一种证明,克服原文中的缺陷。方法设A∈B(H),其中B(H)表示作用在H上的所有有界线性算子构成的Banach空间,用W(A)表示A的数值域。采用构造的方法,给出当λ不是数值域W(A)的端点时,Mλ中向量的构造。结果给出了数值域非端点的一个刻画。结论同时给出了GUSTAFSON K E等人著作中定理1.5-2的另外一种证明,这种证明克服了原文中的缺陷。  相似文献   

9.
在偏微分方程研究领域中,对半线性椭圆型方程边值问题的研究一直是主要研究方向之一,特别是半线性椭圆型方程边值问题正解的研究热点不断;该文利用Levay-Schauder不动点定理研究了一类半线性椭圆方程在有界正则域中正解的存在性、不存在性以及解的唯一性,作为定理的应用,给出了一个应用实例.  相似文献   

10.
本文对于尽人皆知的Vitali遮蓋定理作进一步的讨论。为简便计,这些讨论都是在一维空间里进行的.设E是一个点集,M是闭间隔族,其中每一个都不退化为一点.若对于x∈E及任意∈>0存在d∈M使得x∈d,md<∈则称点集E依Vitali意义被M所遮盖.我们常把M中可能存在的可数多个的两两不相交的闭间隔记为:(1)d_1,d_2,…,d_k,…,d_id_j=0(i≠j).定理(Vitali).若有界集E依Vitali意义被M所遮盖,则对于任意∈>OM中存在有限个两两不相交的闭间隔.(2)d_1,d_2,…,d_n d_id_j=0(i≠j)使得  相似文献   

11.
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   

12.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
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.  相似文献   

14.
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.  相似文献   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
<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   

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