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排序方式: 共有3415条查询结果,搜索用时 31 毫秒
51.
Qin Li Chengqing Li Dongyang Long Wai Hong Chan Changji Wang 《Quantum Information Processing》2013,12(7):2427-2439
In this paper, an efficient arbitrated quantum signature scheme is proposed by combining quantum cryptographic techniques and some ideas in classical cryptography. In the presented scheme, the signatory and the receiver can share a long-term secret key with the arbitrator by utilizing the key together with a random number. While in previous quantum signature schemes, the key shared between the signatory and the arbitrator or between the receiver and the arbitrator could be used only once, and thus each time when a signatory needs to sign, the signatory and the receiver have to obtain a new key shared with the arbitrator through a quantum key distribution protocol. Detailed theoretical analysis shows that the proposed scheme is efficient and provably secure. 相似文献
52.
通道在Photoshop中被认为是十分难理解的概念,文章通过颜色模式为RGB的图像阐述了通道的两个主要作用,并详细说明了通道的本质;基于时原色通道及Alpha通道的认识和理解,探讨了如何利用色阶、调整编辑Alphaia通道制作精确的选区并对选区进行各种处理的方法。 相似文献
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Lately, the once powerful one-factor authentication which is based solely on either password, token or biometric approach, appears to be insufficient in addressing the challenges of identity frauds. For example, the sole biometric approach suffers from the privacy invasion and non-revocable issues. Passwords and tokens are easily forgotten and lost. To address these issues, the notion of cancellable biometrics was introduced to denote biometric templates that can be cancelled and replaced with the inclusion of another independent authentication factor. BioHash is a form of cancellable biometrics which mixes a set of user-specific random vectors with biometric features. In verification setting, BioHash is able to deliver extremely low error rates as compared to the sole biometric approach when a genuine token is used. However, this raises the possibility of two identity theft scenarios: (i) stolen-biometrics, in which an impostor possesses intercepted biometric data of sufficient high quality to be considered genuine and (ii) stolen-token, in which an impostor has access to the genuine token and used by the impostor to claim as the genuine user. We found that the recognition rate for the latter case is poorer. In this paper, the quantised random projection ensemble based on the Johnson–Lindenstrauss Lemma is used to establish the mathematical foundation of BioHash. Based on this model, we elucidate the characteristics of BioHash in pattern recognition as well as security view points and propose new methods to rectify the stolen-token problem. 相似文献
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在GPU渲染及虚拟人理论基础上建立一个包含人体脏腑结构、骨骼和穴位的虚拟经络的研究系统.分析系统的整体结构,并阐述系统各模块的具体实现,内容包括模型获取、模型操作、穴位拾取算法和GPU渲染,最后通过GPU渲染与传统方式渲染的比较,给出实验结果. 相似文献
57.
Zheng Baihua Lee Wang-Chien Liu Peng Lee Dik Lun Ding Xuhua 《Knowledge and Data Engineering, IEEE Transactions on》2009,21(12):1783-1797
In this paper, we investigate the trade off between performance and confidentiality in signature-based air indexing schemes for wireless data broadcast. Two metrics, namely, false drop probability and false guess probability, are defined to quantify the filtering efficiency and confidentiality loss of a signature scheme. Our analysis reveals that false drop probability and false guess probability share a similar trend as the tuning parameters of a signature scheme change and it is impossible to achieve a low false drop probability and a high false guess probability simultaneously. In order to balance the performance and confidentiality, we perform an analysis to provide a guidance for parameter settings of the signature schemes to meet different system requirements. In addition, we propose the jump pointer technique and the XOR signature scheme to further improve the performance and confidentiality. A comprehensive simulation has been conducted to validate our findings. 相似文献
58.
Yong-Xi Gong 《计算机科学技术学报》2009,24(3):568-577
An algorithm for Boolean operations on conic polygons is proposed.Conic polygons are polygons consisting of conic segments or bounded conics with directions.Preliminaries of Boolean operations on general polygons are presented.In our algorithm,the intersection points and the topological relationships between two conic polygons are computed.Boundaries are obtained by tracking path and selecting uncrossed boundaries following rule tables to build resulting conic polygons. We define a set of rules for the i... 相似文献
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中国戏曲脸谱有着深厚的文化意蕴和丰富的历史内容,其艺术特征主要有装饰性、程式性、象征性等特征。从戏曲脸谱的这些特点中,我们也能找到很多可以供给现代设计借鉴的内容。本文探索何把中国文化博大精深的内涵应用到现代设计中去,从中国戏曲脸谱艺术里汲取现代产品造型设计的灵感,探讨现代设计与中国传统文化的关系。 相似文献
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