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91.
<正>经济发展模式的根本转变党的十七大第一次提出了生态文明的概念,并且把建设生态文明列入全面建设小康社会的奋斗目标,这是我国经济发展模式的根本转变,是我们党对发展理念的理论升华,具有十分重要的现实意义和深远意义。 相似文献
92.
XUE Rui 《中国科学:信息科学(英文版)》2013,(3):179-189
Key-privacy is a notion of security that is concerned with the key anonymity in public-key encryption.Some popular schemes keep key-privacy,while others do not.Key-privacy has been shown to be orthogonal to data-privacy within one cryptosystem.This paper investigates the relationship between keyprivacy and data-privacy in public-key encryption.We show that the existence of IK-CPA secure cryptosystems implies the existence of IE-CCA secure cryptosystems in the random oracle model.The main contributions include a novel construction of a family of injective one-way trapdoor functions directly based on any IK-CPA secure public-key cryptosystem in the random oracle model.This construction adopts a novel idea in the construction compared to the existing one.The latter was based on unapproximable trapdoor predicates.The novelty of the construction allows to show that the injective trapdoor functions are secure under correlated products with respect to uniform repetitional distribution.That further allows us to conclude,in the random oracle model,that the existence of IK-CPA secure public-key cryptosystems implies the existence of CCA secure cryptosystems by a result of Rosen and Segev. 相似文献
93.
以硅烷和乙烯的混合气体的原料气,通过常压化学气相沉积方法在玻璃衬底上生长出了硅薄膜。结合光电子能谱、高分辨电镜以及薄膜抗腐蚀性研究,证实乙烯的引入使硅薄膜中形成一定数量的SiC微晶粒。SiC较高的化学稳定性使薄膜具有较强的耐碱性,而其较小的折射率使薄膜的镜面反射率较高低。含有SiC的硅薄膜经碱液适当腐蚀后能降低镜面反射,进而有可能减少光污染现象。 相似文献
94.
Zhang Qian Shi Jiaoying CaiHong CAD & CG State Key Lab. Zhejiang University Foshan Enterprise Postdoctoral Workstaion 《计算机辅助绘图.设计与制造(英文版)》1997,(2)
TwoAlgorithmsforFastPolyhedronRay-TracingZhangQianShiJiaoyingCaiHongCAD&CGStateKeyLab.,ZhejiangUniversity,310027FoshanEnterpr... 相似文献
95.
GU Yuantao TANG Kun & CUI Huijuan State Key Laboratory on Microwave Digital Communications Department of Electronics Engineering Tsinghua University Beijing China Correspondence should be addressed to Gu Yuantao 《中国科学F辑(英文版)》2004,(2)
In several branches of adaptive filtering algorithms, the least mean square (LMS) algorithm is widely applied in many areas because of its low computational cost, good numerical stability and other features[1]. However, the contradiction between faster convergence and smaller steady-state mean squared error (MSE) affects its performance considerably. Step-size, as the key to the problem, can but offer only one choice of the two demands. Therefore, many variable step-size algorithms were prop… 相似文献
96.
A property-based attestation protocol for TCM 总被引:1,自引:0,他引:1
This paper presents a property attestation protocol for the security chip TCM (trusted cryptographic module) via analyzing the problems of the current property attestation, which is built on the property attestation model with the online trust third party. In the protocol the prover utilizes the zero-knowledge proof by the attribute certificates, configuration commitment and TCM signature, and attests its configuration and status which are compliant with the declarative security property. The protocol is ch... 相似文献
97.
本系统结合网络安全通信系统的应用需求和功能需求两方面,在深入研究实现数据加密技术的对称密钥密码体制和公开密钥密码体制的基础上,提出了一套网络安全通信系统的设计方案。实验表明,该系统能确保通信双方能够实现网络中聊天和文件传输的安全,它体现了消息保密性和消息认证性两方面的安全特性。 相似文献
98.
PAN Bin ZHONG Fan WANG Shuai CHEN Wei & PENG QunSheng The State Key Lab of CAD & CG Hangzhou China 《中国科学:信息科学(英文版)》2011,(6):1199-1206
Salient structural elements are ubiquitous in natural textures, and their distribution exhibits some stochastic distribution features. Current texture synthesis algorithms can neither preserve the integrity of the elements nor capture this distributive information. We present an algorithm to treat this high-level visual information. Here, we address the issue by taking specific care of the structural elements. Our texture synthesis process grows the target texture one structural element at a time. A Markov ... 相似文献
99.
LANG Bo State Key Laboratory of Software Development Environment Beihang University Beijing China 《中国科学:信息科学(英文版)》2010,(5):896-910
Trust brings a new method for building scalable and fine-grained access control mechanism in P2P systems. The quantificational expression of trust and the calculation of trust in a trust network are the basis of trust degree based access control. In this paper, the properties of trust is analyzed by referring to the fruits from social science; the semantics of trust in the context of access control is described, and a trust degree based access control model named TDBAC is introduced. Basing on the propertie... 相似文献
100.