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A New Revocable and Re-Delegable Proxy Signature and Its Application

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Journal of Computer Science & Technology 2018年第2期33卷 380-399页

作者： Shengmin Xu Guomin Yang yi mu Institute of Cybersecurity and Cryptology School of Computing and Information Technology University of Wollongong Wollongong 2500 Australia

With the popularity of cloud computing and mobile Apps, on-demand services such as on-line music or audio streaming and vehicle booking are widely available nowadays. In order to allow efficient delivery and management of the services, for large-scale on-demand systems, there is usually a hierarchy where the service provider can delegate its service to a top-tier （e.g., countrywide） proxy who can then further delegate the service to lower level （e.g., region-wide） proxies. Secure （re-）delegation and revocation are among the most crucial factors for such systems. In this paper, we investigate the practical solutions for achieving re-delegation and revocation utilizing proxy signature. Although proxy signature has been extensively studied in the literature, no previous solution can achieve both properties. To fill the gap, we introduce the notion of revocable and re-delegable proxy signature that supports efficient revocation and allows a proxy signer to re-delegate its signing right to other proxy signers without the interaction with the original signer. We define the formal security models for this new primitive and present an efficient scheme that can achieve all the security properties. We also present a secure on-line revocable and re-delegate vehicle ordering system （RRVOS） as one of the applications of our proposed scheme.

关键词： revocation (re)delegation proxy signature

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CYBERSPACE SECURITY

China Communications 2016年第11期13卷 68-69页

作者： Huanguo Zhang yi mu computer school in wuhan university school of computer science and software engineering centre for computer and information security research at university of wollongong

With rapid development and wide application of information technology,mankind is entering into an information *** world where people live and work has been changed to a brand new triple-dimensional space that consists of the physical world,the human society and the *** is well known that the cyberspace is an essential environment of human existence and development and it

关键词：网络空间安全人类社会信息技术信息时代三维空间赛扬

Using FEM to predict tree motion in a wind field

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第7期9卷 907-915页

作者： Xiao-yi HU Wei-ming TAO yi-mu GUO Department of Mechanical Engineering Zhejiang University Hangzhou 310027 China School of Engineering Zhejiang Forestry University Hangzhou 311300 China

In this paper we propose a finite element(FE) simulation method to predict tree motion in a wind field. Two FE tree models were investigated:One model was generated based on a realistic nature-looking geometric tree model,and the other was a symmetric model to investigate the influence of asymmetric material properties on tree motion. The vortex-induced vibration(VIV) theory is introduced to estimate the fluctuating wind force being exerted on tree stems and the fluid-structure interaction(FSI) analysis is also included in the simulation. The results indicate that asymmetric material properties result in the crosswind displacement of the investigated node and the main swaying direction deviation. The simulation reveals that under wind loading,a tree with leaves has much larger swaying amplitude along the wind direction and longer swaying period than a tree without leaves. However,the crosswind swaying amplitude is mainly due to branch interaction. The numerical simulation proved that the inter-action of tree branches can prevent dangerous swaying motion developing.

关键词： Finite element method (FEM) Fluid-structure interaction (FSI) Vortex-induced vibration (VIV) Asymmetric Wind field

An improved Durandal signature scheme

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Science China(Information Sciences) 2020年第3期63卷 140-155页

作者： Yongcheng SONG Xinyi HUANG yi mu Wei WU Fujian Provincial Key Laboratory of Network Security and Cryptology College of Mathematics and InformaticsFujian Normal University

Constructing secure and effective code-based signature schemes has been an open problem. In this paper, we efficiently reduce the key size of the Durandal signature scheme introduced by Aragon et al.(EUROCRYPT 2019). We prove that the improved scheme is EUF-CMA secure by reducing its security to the advanced product spaces subspaces indistinguishability(PSSI+) problem, the decisional rank syndrome decoding(DRSD) problem, and the affine rank syndrome decoding(ARSD) problem under the random oracle model. Furthermore, our signature scheme is more secure than the Durandal scheme because recovering key attacks are equivalent to solving the rank syndrome decoding(RSD) problem, instead of the rank support learning(RSL) problem in the original Durandal scheme. Our signature scheme takes less time to generate a signature owing to the fact that our signature scheme enjoys smaller security parameters in comparison to the Duradual scheme. We compare the new scheme with existing code-based signature schemes and find that our signature scheme has advantages in terms of the public key size.

关键词： post-quantum cryptography code-based cryptography rank metric digital signatures provable security

Efficient and secure image authentication with robustness and versatility

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Science China(Information Sciences) 2020年第12期63卷 179-196页

作者： Haixia CHEN Xinyi HUANG Wei WU yi mu Fujian Provincial Key Laboratory of Network Security and Cryptology Center for Applied Mathematics of Fujian ProvinceCollege of Mathematics and Informatics Fujian Normal University

Image authentication is the technology of verifying image origin, integrity and authenticity. A rich stream of research on image authentication has shown various trade-off among four favorable features,namely robustness, security, versatility and efficiency. Image data authentication has the highest level of security but provides no robustness/versatility. Image content authentication from robust hashing keeps robust to limited types of operations, and as a result its versatility is not satisfactory. Existing designs of image content authentication from advanced cryptographic primitives achieve robustness, security and versatility, at the cost of low efficiency. In this paper, we present a new design of image authentication with an improved trade-off among the aforementioned features. Our versatile design is robust to a number of predefined image processing operations. Its security can be reduced to q-strong Diffie-Hellman(q-SDH), a complexity problem used by existing cryptographic algorithms. From the aspect of efficiency, the new design has a constant-size authentication overhead( ≤2 kB) and a constant verification time(around 0.05 s). While the time of generating authentication overhead increases linearly with the number of permissible editing operations, it only takes around 0.33 s for 1000 types of permissible operations. We believe the new design will facilitate image applications where trustworthy image editing is required.

关键词： image authentication image processing cryptography bilinear maps

Surface-exchange of NOx and NH_3 above a winter wheat field in the Yangtze Delta, China

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Journal of Environmental Sciences 2006年第4期18卷 689-700页

作者： FANG Shuang-xi ZHANG yi mu Yu-jing Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

A four-dynamic-chamber system was constructed to measure NOx and NH3 surface-exchange between a typical wheat field and the atmosphere in the Yangtze Delta, China. The average fluxes of NO, NO2 and NH3 were 79, -5.6 and -5.1 ngN/（m^2·s）, and 91, -1.8 and 23 ngN/（m^2·s）, respectively for the wheat field and the bare soil. The NO flux was positively correlated with soil temperature and the fluxes of NO2 and NH3 were negatively correlated with their ambient concentrations during the investigated period. The compensation point of NO2 between the wheat field and the atmosphere was 11.9 μg/m3. The emissions of NO-N and NH3-N from the urea applied to the wheat field were 2.3% and 0.2%, respectively, which indicated that the main pathway of N loss from the investigated winter wheat field was NO. Application of a mixture of urea and lignin increased the emissions of NO, but also greatly increased the yield of the winter wheat.

关键词： NOx NH3, flux surface-exchange

A Solution of Grid Computing Flow Using MDA Methodology

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The Journal of China Universities of Posts and Telecommunications 2006年第1期13卷 29-33页

作者： JI yi-mu WANG Ru-chuan Department of Computer Science Nanjing University of Posts and Telecommunications Nanjing 210003 P.R. China State Key Laboratory for Novel Software Technology Nanjing University Nanjing 210093 P.R. China

This paper presents an approach to build a flow of grid services named GFlow. This approach converts all of the services＇ interfaces in globus toolkit 3 into platform independent model format. The conversion uses eclipse modeling framework plug-ins and graphical editing framework plug-ins to parse the models into platform specific models, which are responsible for implementation of grid services＇ clients and servers and their automatic deployment. This paper emphasizes on design method, which uses model drive architecture, and design process, which uses model-view-control.

关键词： grid computing platform MDA open grid service infrastructure MVC architecture

A two-stage amplifier of laser eavesdropping model based on waveguide fiber taper

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Defence Technology（防务技术） 2019年第1期15卷 95-97页

作者： Mei-ting Wang Yan Zhu yi-ning mu School of Science Changchun University of Science and Technology

In order to improve ability of amplification about optical arrival angle in laser eavesdropping system, and enhance receiving field of view (FOV) of laser eavesdropping system, this paper presents a new multistage amplifier laser eavesdropping model based on waveguide fiber taper. First of all, taking about four-quadrant (4QD) laser eavesdropping model as an example, from the theoretical view, analyses factors that, currently, laser eavesdropping system face many restrictive factors during practical applications. Besides, from the receiving FOV and ability of amplification about arrival angle of incoming optical axis angles, systematically analyses advantages of multi-stage amplifier model. What’s more,through constructing laser eavesdropping test platform, we demonstrate Signal to Noise Ratio(SNR) of two stage amplification model is eventually promoted to 6-10 dB compared with one amplifying model,especially in low and high audio level, the advantages is more obvious.

关键词： Laser eavesdropping Waveguide fiber taper 4QD

Private Keyword-Search for Database Systems Against Insider Attacks

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Journal of Computer Science & Technology 2017年第3期32卷 599-617页

作者： Peng Jiang yi mu Fuchun Guo Qiao-Yan Wen State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China Centre for Computer and Information Security Research School of Computing and Information Technology University of Wollongong Wollongong NSW 2522 Australia

The notion of searchable encrypted keywords introduced an elegant approach to retrieve encrypted data without the need of decryption. Since the introduction of this notion, there are two main searchable encrypted keywords techniques, symmetric searchable encryption （SSE） and public key encryption with keyword search （PEKS）. Due to the complicated key management problem in SSE, a number of concrete PEKS constructions have been proposed to overcome it. However, the security of these PEKS schemes was only weakly defined in presence of outsider attacks;therefore they suffer from keyword guessing attacks from the database server as an insider. How to resist insider attacks remains a challenging problem. We propose the first searchable encrypted keywords against insider attacks （SEK-IA） framework to address this problem. The security model of SEK-IA under public key environment is rebuilt. We give a concrete SEK-IA construction featured with a constant-size trapdoor and the proposed scheme is formally proved to be secure against insider attacks. The performance evaluations show that the communication cost between the receiver and the server in our SEK-IA scheme remains constant, independent of the sender identity set size, and the receiver needs the minimized computational cost to generate a trapdoor to search the data from multiple senders.

关键词： public key encryption with keyword search keyword privacy insider attack searchable encrypted keyword