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New family of piecewise smooth support vector machine

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Journal of Systems Engineering and Electronics 2015年第3期26卷 618-625页

作者： Qing Wu leyou zhang Wan Wang School of Automation Xi'an University of Posts and Telecommunications School of Mathematics and Statistics Xidian University School of Computer Science and Technology Xi'an University of Posts and Telecommunications

Support vector machines （SVMs） have been extensively studied and have shown remarkable success in many applications. A new family of twice continuously differentiable piecewise smooth functions are used to smooth the objective function of uncon- strained SVMs. The three-order piecewise smooth support vector machine （TPWSSVMd） is proposed. The piecewise functions can get higher and higher approximation accuracy as required with the increase of parameter d. The global convergence proof of TPWSSVMd is given with the rough set theory. TPWSSVMd can efficiently handle large scale and high dimensional problems. Nu- merical results demonstrate TPWSSVMa has better classification performance and learning efficiency than other competitive base- lines.

关键词： support vector machine (SVM) piecewise smooth function smooth technique bound of convergence.

Adjustable entropy function method for support vector machine

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Journal of Systems Engineering and Electronics 2008年第5期19卷 1029-1034页

作者： Wu Qing Liu Sanyang zhang leyou Dept. of Mathematical Sciences Xidian Univ. Xi'an 710071 P. R. China

Based on KKT complementary condition in optimization theory, an unconstrained non-differential optimization model for support vector machine is proposed. An adjustable entropy function method is given to deal with the proposed optimization problem and the Newton algorithm is used to figure out the optimal solution. The proposed method can find an optimal solution with a relatively small parameter p, which avoids the numerical overflow in the traditional entropy function methods. It is a new approach to solve support vector machine. The theoretical analysis and experimental results illustrate the feasibility and efficiency of the proposed algorithm.

关键词： optimization support vector machine adjustable entropy function Newton algorithm.

Privacy preserving ciphertext-policy attribute-based broadcast encryption in smart city

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The Journal of China Universities of Posts and Telecommunications 2019年第1期26卷 21-31页

作者： Cui Yilei zhang leyou School of Mathematics and Statistics Xidian University

With the development and application of information technology, the problem of personal privacy leakage is becoming more and more serious. Most attribute-based broadcast encryption(ABBE) schemes focus on data security, while ignoring the protection of the personal privacy of users in access structure and identity. To address this problem, a privacy preserving ABBE scheme is proposed, which ensures the data confidentiality and protects personal privacy as well. In addition, the authenticity of encrypted data can be verified. It is proved that the proposed scheme achieves full security by dual system encryption.

关键词： smart city attribute-based broadcast encryption privacy preserving full security

Continual auxiliary leakage-resilient attribute-based broadcast encryption with constant size ciphertexts

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The Journal of China Universities of Posts and Telecommunications 2020年第4期27卷 69-82页

作者： Shang Yujie zhang leyou Gao Xiaoxu School of Mathematics and Statistics Xidian UniversityXi’an 710126China

Attribute-based broadcast encryption(ABBE) under continual auxiliary leakage-resilient(CALR) model can enhance the security of the shared data in broadcasting system since CALR model brings the possibility of new leakage-resilient(LR) guarantees. However, there are many shortcomings in the existing works, such as relying on the strong assumptions, low computational efficiency and large size of ciphertexts, etc. How to solve the trade-off between security and efficiency is a challenging problem at present. To solve these problems, this paper gives an ABBE scheme resisting continual auxiliary leakage(CAL) attack. ABBE scheme achieves constant size ciphertexts, and the computational complexity of decryption only depends on the number of receivers instead of the maximum number of receivers of the system. Additionally, it achieves adaptive security in the standard model where the security is reduced to the general subgroup decision(GSD) assumptions(or called static assumptions in the subgroup). Furthermore, it can tolerate leakage on the master secret key and private key with continual auxiliary inputs. Performance analysis shows that the proposed scheme is more efficient and practical than the available schemes.

关键词： CALR model leakage-resilient cryptography attribute-based broadcast encryption constant size ciphertext

Attribute-based encryption resilient to continual auxiliary leakage with constant size ciphertexts

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The Journal of China Universities of Posts and Telecommunications 2016年第3期23卷 18-28页

作者： zhang leyou zhang Jingxia Hu Yupu School of Mathematics and Statistics Xidian University School of Telecommunications Engineering Xidian University

For leakage-resilient ciphertext-policy attribute-based encryption （CP-ABE） at present, the size of the ciphertexts in most of them relies on the number of attributes. How to overcome this shortcoming is a challenge problem. Based on the Goldreich-Levin theorem and dual system encryption, an efficient CP-ABE scheme with constant size ciphertexts is proposed in this paper. It can tolerate leakage on master secret key and attribute-based secret keys with auxiliary inputs. Furthermore, the proposed scheme can be realized as resilience against continual leakage if keys are periodically updated. Under some static assumptions instead of other strong assumptions, the introduced scheme achieves adaptively security in the standard model.

关键词： ciphertext-policy attribute-based encryption (CP-ABE) constant size ciphertexts auxiliary input leakage-resilient

New Constructions of Identity-Based Threshold Decryption

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Wuhan University Journal of Natural Sciences 2010年第3期15卷 222-226页

作者： zhang leyou HU Yupu TIAN Xu'an YANG Yang Department of Mathematical Science Xidian University Xi'an 710071 Shaanxi China Key Laboratory of Computer Networks and Information Security of Ministry of Education Xidian University Xi'an 710071 Shaanxi China Xi'an Communications Institute Xi'an 710106 Shaanxi China

In this paper, based on the verifiable pair and identity-based threshold cryptography, a novel identity-based （ID-based） threshold decryption scheme （IDTDS） is proposed, which is provably secure against adaptive chosen cipbertext attack under the computational bilinear Diffie-Hellman （CBDH） problem assumption in the random oracle. The pubic cheekability of ciphertext in the IDTDS is given by simply creating a signed E1Gamal encryption instead of a noninteractive zero-knowledge proof. Furthermore, we introduce a modified verifiable pairing to ensure all decryption shares are consistent. Our scheme is more efficient in verification than the schemes considered previously.

关键词： ID-Based threshold decryption verifiable pair computational bilinear Diffie-Hellman (CBDH) problem provable security

Porphyrin functionalized NiO nanoparticles: Promising peroxidase mimetics for H2O2 and glucose detection

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Porphyrin functionalized NiO nanoparticles: Promising peroxi...

A facile preparation of montmorillonite-supported copper sulfide nanocomposites and their application in the detection of H2O2

中国化学会第九届全国无机化学学术会议

作者： Qingyun Liu Yanting Yang leyou zhang Yanyuan Ding Department of Chemistry Shandong University of Science ＆ Technology

NiO nanoparticles（NPs） and 5,10,15,20-tetrakis（4-carboxyl pheyl）-porphyrin（H2TCPP） functionalized NiO nanoparticles（H2TCPP-Ni O nanocomposites） have been prepared by a facile method and characterized by powder X-ray diffraction（XRD）, transmission electron microscope（TEM） and Fourier transform infrared spectra（FTIR）, respectively. NiO NPs and H2TCPP-NiO nanocomposites have been proven to function as peroxidase mimetics that can catalyze the reaction of peroxidase substrate 3,3’,5,5’-tetramethylbenzidine（TMB） in the presence of H2O2 to produce a blue color reaction. Kinetic analysis indicated that the catalytic behavior was in accord with typical Michaelis–Menten kinetics. And these nanoparticles also exhibited strong affinity for the substrates of 3,3,5,5-tetramethylbiphenyl dihydrochloride（TMB）. Experimental results showed that H2TCPP-NiO NPs exhibited a high sensitivity and a low detection limit towards H2O2（8.0×10-6 M）. The H2TCPP-NiO NPs/glucose oxidase（GOx）/TMB system provides a novel colorimetric sensor for glucose and shows good response toward glucose detection over arrange of 0.05–0.50 mM with a limit of detection 2.0×10-5 M. Fluorescence probe experiments demonstrated that the peroxidase-like activity of H2TCPP-NiO NPs originated from the generation of ·OH radical. Thus it may provide great potential applications in biomedicine, biotechnology and environmental chemistry.

关键词： porphyrin NiO peroxidase glucose colorimetric

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A facile preparation of montmorillonite-supported copper sul...

标准模型下一种新的基于分级身份的短签名方案

第七届全国物理无机化学学术会议

作者： Miaomiao Chen leyou zhang Yanan Ding Mingxing Chen Qingyun Liu College of Chemical and Environmental Engineering Shandong University of Science and Technology

＜正＞Well-dispersed nanocomposites（Cu S-MMT nanocomposites）were prepared by a facile method under the hydrothermal condition and were characterized by the powder X-ray diffraction（XRD）,transmission electron microscopy（TEM）,high resolution TEM and energy-dispersive X-ray spectroscopy（EDS）.The as-prepared Cu S-MMT NPs were firstly demonstrated to possess intrinsic peroxidase-like activity towards

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计算机研究与发展 2011年第8期48卷 1357-1362页

作者：吴青张乐友胡予濮西安邮电学院自动化学院西安710121 西安电子科技大学数学系西安710071 计算机网络与信息安全教育部重点实验室(西安电子科技大学) 西安710071

基于分级身份的签名在大规模网络中具有重要应用前景,为克服已有方案的私钥或签名长度依赖于分级级数及最大分级级数的缺陷,提高计算效率,提出了一种新的基于分级身份的签名方案.与已有方案相比,新方案优势明显,如身份分级级数越大,私... 详细信息

基于分级身份的签名在大规模网络中具有重要应用前景,为克服已有方案的私钥或签名长度依赖于分级级数及最大分级级数的缺陷,提高计算效率,提出了一种新的基于分级身份的签名方案.与已有方案相比,新方案优势明显,如身份分级级数越大,私钥长度越短,且签名长度为常数,仅含有3个群元素.验证算法仅需要3个双线性对运算,同样不依赖于分级级数.另外,新方案的安全性建立在推广的选择身份安全模型,该模型为适应性选择身份安全模型及选择身份安全模型的推广,在计算h-CDH困难假设下,新方案被证明是安全存在性不可伪造的,且其安全性不依赖于随机预言机.与已有的标准模型下的分级方案相比,新方案的安全性基于的困难假设更具有一般性.

关键词：基于分级身份的签名标准模型 h-CDH问题可证明安全推广的选择身份安全模型