基于2DPCA的眉毛识别方法研究

分析了人类的眉毛作为一种独立生物特征进行身份鉴别的可能性,提出了一种基于2DPCA的眉毛识别方法,比较了2DPCA和PCA对眉毛识别的结果.通过对109人的眉毛数据库的分析,分别研究了2DPCA和PCA方法在眉毛识别中识别率和信息阈值之间,识别率与特征个数之间,识别率与图像尺寸之间的关系,以及它们对时间和空间的需求.实验结果表明,利用2DPCA方法进行眉毛识别在训练时间和识别率上明显优于PCA方法,识别率最高可达97.62%.     

A Quantum Private Query Protocol for Enhancing both User and Database Privacy

In order to protect the privacy of query user and database, some QKD-based quantum private query(QPQ)protocols were proposed. Unfortunately some of them cannot resist internal attack from database perfectly; some others can ensure better user privacy but require a reduction of database privacy. In this paper, a novel two-way QPQ protocol is proposed to ensure the privacy of both sides of communication. In our protocol, user makes initial quantum states and derives the key bit by comparing initial quantum state and outcome state returned from database by ctrl or shift mode instead of announcing two non-orthogonal qubits as others which may leak part secret information. In this way,not only the privacy of database be ensured but also user privacy is strengthened. Furthermore, our protocol can also realize the security of loss-tolerance, cheat-sensitive, and resisting JM attack etc.     

A Quantum Protocol for Millionaire Problem with Continuous Variables

In this paper, a protocol for quantum millionaire problem with continuous variables is proposed. In the protocol, two participants can compare the values of their fortune with the assistance of a semi-trusted third party （STTP）. Only EPR states are exploited in our protocol while most other protocols exploited d-dimensional Bell states. Two participants are just required to perform single particle operations, which makes our protocol more efficiently. Our protocol can ensure fairness, correctness, security and high efficiency as well. In our protocol, only the two participants can deduce the results of comparisons, others include STTP will learn no information. Our protocol can resist various kinds of attacks from both the outside eavesdroppers and the inside participants, even the STTP.