Digital watermarking is the enabling technology to prove ownership on such copyrighted product as software, documents, music, and video, monitor the usage of them, and even trace them back to the user with embedding o...Digital watermarking is the enabling technology to prove ownership on such copyrighted product as software, documents, music, and video, monitor the usage of them, and even trace them back to the user with embedding of unique buyer identification(ID) as a part of watermark into them. This thread of detection will deter users from releasing unauthorized copies. A problem arises when the seller is dishonesty, he has a chance to use the digital watermarking with the buyer ID maliciously and make the buyer receive false-accusation. In this paper, an improved digital watermarking scheme is introduced to prevent false-accusation to an honest buyer, which is combined with the advantage of PKC(public key certificate) so that it fits the on-line transaction and helps to realize secure e-commerce. In addition, the extended application of this scheme is discussed.展开更多
The objective of this study is to experimentally investigate the effectiveness of Tuned Liquid Dampers (TLDs) for suppressing the dynamic response of a platform structure subjected to wave loading and to explore the a...The objective of this study is to experimentally investigate the effectiveness of Tuned Liquid Dampers (TLDs) for suppressing the dynamic response of a platform structure subjected to wave loading and to explore the applicability of TLDs for suppressing the structural vibration of fixed offshore platforms. The experimental model is scaled according to a full size platform by matching its dynamic properties. Rectangular and circular TLDs of various sizes and water depths are examined. The experiments were performed in a 2-D wave flume. The effectiveness of TLDs is evaluated based on their response reduction. By observing the performance and the behavior of TLDs through laboratory experiments, the effects of a number of parameters including container shape, container size, number of dampers, frequency ratio, mass ratio, and incident wave characteristics are investigated.展开更多
文摘Digital watermarking is the enabling technology to prove ownership on such copyrighted product as software, documents, music, and video, monitor the usage of them, and even trace them back to the user with embedding of unique buyer identification(ID) as a part of watermark into them. This thread of detection will deter users from releasing unauthorized copies. A problem arises when the seller is dishonesty, he has a chance to use the digital watermarking with the buyer ID maliciously and make the buyer receive false-accusation. In this paper, an improved digital watermarking scheme is introduced to prevent false-accusation to an honest buyer, which is combined with the advantage of PKC(public key certificate) so that it fits the on-line transaction and helps to realize secure e-commerce. In addition, the extended application of this scheme is discussed.
基金financially supported partially by the National Natural Science Foundation of China(No.G50179014)Ph.D.Education Fund from Education Ministry of China.
文摘The objective of this study is to experimentally investigate the effectiveness of Tuned Liquid Dampers (TLDs) for suppressing the dynamic response of a platform structure subjected to wave loading and to explore the applicability of TLDs for suppressing the structural vibration of fixed offshore platforms. The experimental model is scaled according to a full size platform by matching its dynamic properties. Rectangular and circular TLDs of various sizes and water depths are examined. The experiments were performed in a 2-D wave flume. The effectiveness of TLDs is evaluated based on their response reduction. By observing the performance and the behavior of TLDs through laboratory experiments, the effects of a number of parameters including container shape, container size, number of dampers, frequency ratio, mass ratio, and incident wave characteristics are investigated.