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11.
Zhaozhi ZHANG Nan JIANG 《系统科学与复杂性》2007,20(4):486-491
Most cipher systems designed thus far are binary-valued or integer-valued cipher systems. Their security relies on the assumption that one-way functions exist. Though the existence of one-way functions has not been proved yet, most cryptographic researchers believe that one-way functions exist. In addition, many candidates for one-way functions have been proposed. Therefore, the key step for developing real-valued cipher systems is to define real one-way functions and to propose candidates for them. In this paper, based on computational complexity theory over the real field, we give two definitions of real one-way functions; one is for digital one-way functions and the other is for general one-way functions. Candidates for these two classes of one-way functions are also proposed. Moreover, we present two examples to demonstrate that the candidates for both digital one-way functions and general one-way functions can be applied to construct secure real-valued cipher systems. 相似文献
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《Studies in history and philosophy of science》2013,44(4):643-651
For many years, scientific heritage has received attention from multiple actors from different spheres of activity—archives, museums, scientific institutions. Beyond the heterogeneity revealed when examining the place of scientific heritage in different places, an authentic patrimonial configuration emerges and takes the form of a nebula of claims and of accomplishments that result, in some cases, in institutional and political recognition at the national level, in various country all around the world. At the international level, the creation of the international committee dedicated to University Museums and Collections (UMAC) within the International Council of Museums (ICOM) certainly testified from this raising interest in academic heritage and the existence of a specific community concern with it.This article presents numerous initiatives for the preservation of scientific heritage in France, with the goal of analysing the relationship scientists have with their heritage. We argue that scientific communities have a special relationship with heritage, which is characterized by a number of ambiguities. We show that such ambivalences allow analysis of identity, discipline, professional, and social issues operative in defining heritage and being redefined by heritage. To explore these dimensions, we have chosen to present three different case studies. The first traces the institutional uses of heritage by a scientific institution, the Commissariat à l’énergie atomique (CEA), through the transformation of the first French atomic reactor (ZOE) into a museum. The second example describes the initiatives of French astronomers from the mid-1990s to construct a national programme for the protection of astronomy heritage. Lastly, we recount the case of universities, with the example of the Université de Strasbourg. 相似文献
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政治认同意味着人民大众对政治系统的认可与支持。和谐社会因政治认同而存在合法性基础,和谐社会因政治认同而焕发出强大的精神动力,和谐社会也因为实现了政治认同而区别于一般性的稳定的社会。文中从合法性基础、精神动力与价值内核三个方面论述了政治认同对于构建社会主义和谐社会的价值之所在。 相似文献
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罗树杰 《广西民族大学学报》2005,(4)
于鹏杰同志的《族群认同的现代含义:以湖南城步苗族为例》认为中国政府的民族政策使得许多民族自愿或不自愿的采用了汉族的生活方式,并导致了新时代文化认同与族群认同的困惑。如此评价,实有误解乃至歪曲中国政府民族政策的嫌疑。新时代族群认同的困惑不是由于中国政府的民族政策造成的,而是在于“族群”概念的不确定性和民族、族群认同表现的多样性。 相似文献
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谢继昌 《广西民族大学学报》2005,(5)
沙阿鲁阿族是台湾原住民邹族的三大族群之一,以三民乡民权村的沙阿鲁阿族来看,民权村的原住民以布农族为主,其次为沙阿鲁阿族和堪卡那福族,通用的原住民语言是布农语,沙阿鲁阿族和堪卡那福族的后裔,多年来被视为或自视为布农族而不自觉。但近年来随着族群意识的高涨,后二族群的后裔,纷纷挺身而出,声称自己的族群认同。从中我们看到国家与地方的折衷以及不同族群间的冲突与妥协。如何为族群间寻求一相处之道,是今日当务之急。 相似文献
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基于集群系统的导弹流场并行数值模拟 总被引:2,自引:0,他引:2
采用36颗安腾2处理器和Infiniband网络设备构建了一套18节点的高性能计算集群系统,经过性能调优,其Linpack值达到每秒可执行1 886亿次浮点运算(188.6 GFlops)的水平.然后,将集群系统扩展为适用于计算流体力学并行应用的数值模拟平台.建立了约为783万结构化网格的战术导弹三维流场仿真模型,通过网格分区算法将模型移植到集群系统上并行求解,并测试了集群系统的性能.结果表明,构建的CFD数值模拟平台硬、软件资源配置合理,能够适用于中等规模的CFD并行仿真. 相似文献
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周持中 《湖南理工学院学报:自然科学版》2000,13(1):1-6
l introductionIn 1991, L. Shapiro and his co -- authorsI2] gave the following.Definition l.l Let L = (l.i),.j >0 be a infinite matrix with entries that belong to the fieldC of complex numbers, and letbe the GF of the i,, column of L. Then L is called a Riodan matrix ifwb e reandsuch that g(x) and f(x) belong to the ring of formal power series C[x] and f, /0.The Riodan matrix has many applications to combinatoricsll]--14]. For example, in 1997,N. Asamoah[I] dealt with the problem of latt… 相似文献