Guoyan Zhang

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In Eurocrypt’05, Wang et al. presented new techniques to find collisions of Hash function MD4. The techniques are not only efficient to search for collisions, but also applicable to explore the secondpreimage of MD4. About the second-preimage attack, they showed that a random message was a weak message with probability 2−122 and it only needed a one-time(More)
In this paper, we propose a new data mining algorithm, which is used in surveillance video of stationary places. The algorithm combines Background Subtraction with Symmetrical Differencing in order to extract moving targets. According to the amount of motions occurring in video frames, we divide the video into different segments. Video segments are(More)
This paper focuses on building a tweakable blockcipher from a classical blockcipher whose input and output wires all have a size of n bits. The main goal is to achieve full 2 security. Such a tweakable blockcipher was proposed by Mennink at FSE’15, and it is also the only tweakable blockcipher so far that claimed full 2 security to our best knowledge.(More)
Identity-based crypto system has many advantages over PKI-based cryptosystem in key distribution, but key escrow is always an inherent drawback. In order to solve the problem, certificateless public key cryptography was introduced by Al-Riyami and Paterson in [8]. In this paper, we first introduce a certificateless signature scheme secure against both(More)
Photoluminescent polymer dots (PDs) were prepared by a moderate hydrothermal treatment of poly(vinyl alcohol) (PVA). A single excited state was established in the PL mechanism by ultrafast spectroscopy. Moreover, the applied method be used to prepare fluorescent polymer dots from other non-conjugated polymers, and shows general universality.
Different from identity-based encryption scheme, an attribute-based encryption scheme is a scheme in which each user is identified by a set of attributes, and some function of those attributes is used to determine decryption ability for each ciphertext. But key escrow problem is also the inherent problem in attribute-based encryption scheme. To avoid the(More)
The mechanism that leads to a decreased aggregation of beta-lactoglobulin in the presence of dextran sulfate and lambda-carrageenan was investigated by assessing changes in the denaturation thermodynamics and protein structure. Differential scanning calorimetry results showed that the denaturation temperature (Tp) was about 4.6 degrees C higher in the(More)
In this article, we analyse the security of the authenticated encryption mode JAMBU, a submission to the CAESAR competition that remains currently unbroken. We show that the security claims of this candidate regarding its nonce-misuse resistance can be broken. More precisely, we explain a technique to guess in advance a ciphertext block corresponding to a(More)