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1.
一种基于超混沌的二值序列生成方法   总被引:3,自引:1,他引:2  
为了得到具有良好随机性和初值敏感性的二值序列,在已有的超混沌系统的基础上,,给出了一种构造的广义混沌序列产生方法.实验结果经过FIPS140-2测试检验,生成的密钥二值序列具有很好的随机性和初值敏感性满足密码学领域的加密要求.  相似文献   

2.
m序列的伪随机性在理论上已有严格的证明。利用在核物理实验室中使用的多道分析器对m序列脉冲的伪随机特性进行了测试,其结果与理论相符,并对序列的分布作了统计性检验,最后提出一个改进“随机性”的简单方法。  相似文献   

3.
阐述了随机序列在数字产品产权保护措施中的作用,并对随机序列生成器底层逻辑进行了研究;对线性同余发生器存在的缺陷进行了改进,设计了一种新的随机序列发生器,对改进前后发生器进行参数检验、均匀性检验等随机性进行测试,结果表明,改进后的随机序列发生器有较好的随机性和独立性.  相似文献   

4.
混沌系统具有对初值敏感、长期不可预测和伪随机性,在密码学中具备良好的应用基础.针对单混沌系统因计算机有限精度效应容易产生的混沌退化,必须应用一种双混沌映射的序列加密算法.该算法生成的序列符合局部随机性统计检验要求,具有良好的加密性能.  相似文献   

5.
随机游程检验法是用来检验时间序列是否是纯随机的一种方法。本文给出了计算一列股价序列中的游程数、价格上升和价格下降数的程序,并运用随机游程检验法来判断华夏银行2007年11月的股价变化是否具有随机性。  相似文献   

6.
介绍了目前对光量子纠缠态应用的研究状况,成功的将自发参量下转换产生的纠缠光子对应用于产生真随机数.在数据采集过程中采用了符合测量技术,对采集的多组随机序列采用国际上比较通用的随机性测试程序-ENT进行检验,结果表明数据的随机性很好.  相似文献   

7.
用AR模型建立变形预测模型的研究   总被引:4,自引:0,他引:4  
在用时间序列分析方法建立变形测量的预测模型时,基于动态数据系统方法的传统F检验定阶法,由于样本的随机性可能过早地退出对模型的循环检验,从而不能找到合适的预测模型.在探讨如何用AR模型建立变形测量预测模型的基础上,提出了一种改进的建模方法,并在实例的应用中取得了较好的效果.  相似文献   

8.
由于信号所受噪声的随机特性各种各样,为了能更形象模拟实际所受噪声的随机性,设计了一种可参数化的m序列,以此来得到多种随机性的序列。本文设计的m序列发生器采用反馈移位寄存器实现,其可设置参数包括两方面:级数和反馈系数,其中级数有4种设置,反馈系数有3种设置。仿真结果表明:在时钟信号的作用下,级数、反馈系数设置不同,系统输出序列的随机性不同,最后一共可得12种随机特性序列。  相似文献   

9.
给出了通过几种经典的物理混沌系统,包括Chua’s电路、Lorenz系统、Chen系统,产生混沌随机序列的两种离散化方法.用NIST制定的测试标准对产生的随机序列进行了随机性统计测试分析.分别对不同的物理混沌系统产生的随机序列进行单比特频数测试、游程测试、离散傅里叶变换测试、近似熵测试、累积和测试,并进行了比较分析.实验结果表明:物理混沌序列要比算法混沌序列随机性更强,不同序列之间的随机性差异可以通过NIST测试得到体现.在三种经典电路中,建议选择Chen混沌系统的电路做为混沌随机序列发生器.  相似文献   

10.
将不同强度的随机噪声叠加在混沌系统所产生的非线性时间序列上,计算在噪声叠加前后时间序列的复杂度指标,并对计算结果进行对比.实验与计算结果表明:序列复杂度随着随机噪声强度的增加而增大,混沌系统的随机性增强;而当噪声强度过大时,原系统将丢失其非线性动力学特性而转变成随机性系统特征.  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.
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   

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.
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   

15.
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.  相似文献   

16.
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.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
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   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
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   

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