Threshold Subliminal Channel Based on Designated Verifier Signature

The subliminal channel is used to send a secret message to an authorized receiver; the message cannot he discovered by any unauthorized receivers. Designated verifier signature （DVS） provide authentication of a message, we design a DVS scheme with message recovery mechanism and use it as a subliminal channel. In order to share a message among n users securely and allows t or more users can reconstruct the secret in dynamic groups, we combine both subliminal channel and （t, n） threshold cryptography. Then we proposed a threshold subliminal channel which can convey a subliminal message to a group of users based on message-recovery designated verifier signatures. Reconstructing the subliminal message relies on the cooperation of t or more users in the group and they can verify the validity of the subliminal message. Security and performance analysis show that the proposed scheme is secure and efficient.     

一种基于椭圆曲线的强可验证门限阈下信道方案

基于椭圆曲线离散对数问题,提出一种(t,n)-(k,m)强可验证门限阈下信道方案.该方案中n个阈下子信息拥有者中至少t个合作才能得到阈下信息进而生成有效的签名,而m个接收者中至少k个合作才能提取阈下信息.接收者不需要和发送者共享其私钥.通过采用一种可验证门限秘密共享技术,每个接收者可以对提取的子信息有效性进行验证,同时又可以防止接收者对签名进行联合攻击和广义伪造攻击.     

ERP comparison of emotional activity between emotion-facilitation and emotion-interference children

A subliminal emotional Stroop experiment was carried out on 24 5-year-old children with event-related potential (ERP) recording. The children were separated into emotion-facilitation (EF) and emotion-interference (EI) groups based on their behavioral reaction times in emotional and neutral conditions. ERP result of these two groups showed different brain mechanisms of emotional related processing. When processing the emotional stimuli (negative or positive emotional facial pictures), the EI group activated more at the early stage of cognitive processing which was shown as an increase of P2 amplitude, while the lack of resources at the late stage of processing caused less activation which was shown as a decrease of N4 amplitude. The EF group had a reversed processing pattern as the EI group. For all groups of children, the left hemisphere was more sensitive to emotional processing. Furthermore, the positive and negative emotional information showed a similar pattern in the emotional and cognitive processing.     

运动图像中的信息搭载

为了避免在网上传输密文时引起注意 ,信息搭载是一种可行的方法。对于以静态图像为载体的信息搭载方法的研究已有一批成果 ,但以连续运动图像为载体的研究还不多。本文分析了连续图像编码标准 MPEG2 (m oving pictureexperts group)编码的特点 ,论证了以其为信息搭载载体的可行性。提出了信息搭载的数学模型 ,并据此给出了在MPEG2视频部分进行信息搭载的方案 ,该方案针对MPEG2中的不同的帧分别提出了几种具体方法。实践证明 ,针对 MPEG2中 I帧和 B帧、P帧采用不同的搭载的方法 ,可以取得较好的效果     

ERP comparison of emotional activity between emotion-facilitation and emotion-interference children

A subliminal emotional Stroop experiment was carried out on 24 5-year-old children with event-related potential (ERP) recording. The children were separated into emotion-facilitation (EF) and emotion-interference (EI) groups based on their behavioral reaction times in emotional and neutral conditions. ERP result of these two groups showed different brain mechanisms of emotional related processing. When processing the emotional stimuli (negative or positive emotional facial pictures), the EI group activated more at the early stage of cognitive processing which was shown as an increase of P2 amplitude, while the lack of resources at the late stage of processing caused less activation which was shown as a decrease of N4 amplitude. The EF group had a reversed processing pattern as the EI group. For all groups of children, the left hemisphere was more sensitive to emotional processing. Furthermore, the positive and negative emotional information showed a similar pattern in the emotional and cognitive processing.     

Subliminal Channels in the NTRU and the Subliminal-Free Methods

The construetion and destruction of subliminal channel are important problems in the information hiding. The subliminal channel can send secret information without notice. Two subliminal-free methods named weak （strong） subliminal-free on public-key cryptosystem （PKC） are proposed in this paper using the combinatorial method. The first method can only free the subliminal information with any minor probability and the second can free all. Moreover, the ＂traitor problem＂ which is same as the model of the subliminal channel in PKC is given. Two subliminal channels are embedded in N-th degree truncated polynomial ring （NTRU） cryptosystem, and their subliminal-free methods are also be obtained by the action of surveillant.     

一种分割法阈下信道构造方案

提出一种利用求解线性方程组分割法阈下信道构造方案。方案将阈下信息分割转化为几个独立的无害的子消息。通过传输这些子消息的签名的方式将阈下信息的各个子消息传给阈下信息的接收方,阈下信息接收方可根据与签名者共享的秘密信息利用Cramer法则提取出阈下信息。     

一种潜信道方案的改进算法

介绍了数字签名中一类潜信道方案的改进算法，改进后的潜信道被证明可以有效抵抗伪造攻击，且没有降低方案效率以及其它方面的安全性。     

匿名通信技术的研究现状与展望

对匿名通信技术的进展作了综述研究，概述了匿名通信的原理和理论模型，并对目前的匿名浏览、匿名连接、阈下信道等主要技术进行了介绍，分析了目前匿名技术存在的问题，并提出了匿名通信技术的研究方向。     

基于矢量空间秘密共享的阈下信道

通过引入矢量空间秘密共享技术和指定接受者签名加密技术,提出一种新的阁下信道方案,并对该方案进行了安全性分析。在该方案中,任何人都可以对签名进行验证,而只有授权者子集才能提取出阈下信息,阈下信息发送者不需要与接受者的共享私钥,也不需要为接受者生成提取阈下信息的密钥对。