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Full search (FS) motion estimation has have been a big problem in real-time video coding because of enormous amount for calculation. Especially, the recent MPEG-4 AVC (advanced video coding) standard requires much more computations in motion estimation than the conventional MPEG-2 coding standard. In this paper, we propose a fast FS algorithm which can reduce only unnecessary computations significantly. Our algorithm is based on selective matching scan and elimination of unlike candidate blocks from initial matching error. According to the obtained matching order, we proceed to calculate matching errors and remove unlike candidate vectors based on PDE (Partial Distortion Elimination) method. Our algorithm takes about 4~10% of computations for block matching error compared with conventional FS algorithm without any degradation in prediction quality, thus our algorithm will be useful to real-time video coding applications using MPEG-4 AVC or MPEG-2 video coding standards. [ABSTRACT FROM AUTHOR]

Electronic Commerce (EC) has made rapid progress in recent years. Internet auctions have become especially popular in EC. Recently, Jiang-Pan-Li (JPL) proposed an improvement on Chang et al.'s efficient anonymous auction protocols in order to overcome the security weakness in the initiation phase of Chang et al.'s protocol. The current paper, however, points out that JPL's initiation protocol is inefficiently designed and then, two optimized initiation protocols are presented to resolve such problems. Keywords: Security, Auction protocol, Anonymity, Efficiency, Initiation protocol. [ABSTRACT FROM AUTHOR]

Recently, Lin-Hwang proposed a password authentication scheme with secure password updating. The current paper demonstrates the vulnerability of Lin-Hwang's scheme to server data eavesdropping and presents improvements to resolve this problem. In contrast to Lin-Hwang's scheme, the proposed scheme can simply update user passwords without a complicated process and provide explicit key authentication in the case of a session key agreement. Keyword: Cryptography, Password authentication, Key agreement. [ABSTRACT FROM AUTHOR]