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A PREDICTIVE APPROACH TO THE IN-PLANE MECHANICAL PROPERTIES OF STITCHED COMPOSITE LAMINATES

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Acta Mechanica Solida Sinica 2007年第2期20卷 130-140页

作者： zhang Junqian Wei yuqing Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China

This contribution attempts to model the alteration of the in-plane elastic properties in laminates caused by stitching, and to predict the in-plane effective tensile strength of the stitched composite laminates. The distortion of in-plane fibers is considered to be the main cause that affects the in-plane mechanical properties. A fiber distortion model is proposed to characterize the fiber misalignment and the fiber content concentration due to stitching. The undistorted region, the fiber distortion region, the resin-rich pocket and the through-thickness reinforcement section are taken into account. The fiber misalignment and inhomogeneous fiber content due to stitching have been formulated by introducing two parameters, the distortion width and maximum misalignment. It has been found that the ply stress concentration in stitched laminates is influenced by the two concurrent factors, the stitch hole and inhomogeneous fiber content. The stitch hole brings about the stress concentration whereas the higher fiber content at the local region induced by stitching restrains the local deformation of the composite. The model is used to predict the tensile strength of the [0/45/0/-45/90/45/0/-45]58 T300/QY9512 composite laminate stitched by Kevlar 29 yarn with different stitching configurations, showing an acceptable agreement with experimental data.

关键词： stitched composites fiber distortion in-plane elastic properties in-plane tensile strength and micromechanics

Ciphertext-Policy Attribute Based Encryption Supporting Any Monotone Access Structures Without Escrow

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Chinese Journal of Electronics 2017年第3期26卷 640-646页

作者： ZHAO Qianqian zhang yuqing zhang Guanghua WANG He State Key Laboratory of Integrated Services Networks Xidian University National Computer Network Intrusion Protection Center University of Chinese Academy of Sciences Beijing Key Laboratory of IOT Information Security Technology Institute of Information Engineering CAS

Ciphertext policy attribute-based encryption(CP-ABE)is becoming a new primitive for finegrained access *** neither produces multiple encrypted copies of the same data nor suffers from the severe burden of key distribution and *** escrow problem that the central authority could decrypt any ciphertexts addressed to all the specific users is still a challenge for CP-ABE *** new CP-ABE scheme without escrow is proposed,and furthermore the proposed scheme achieves fully security in the standard *** performance and security analysis results indicate that the proposed CP-ABE scheme is extremely appropriate for cloud storage system.

关键词： CP-ABE The escrow problem Fully security In the standard model

A Provably Secure General Construction for Key Exchange Protocols Using Smart Card and Password

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Chinese Journal of Electronics 2017年第2期26卷 271-278页

作者： zhang Gefei FAN Dan zhang yuqing LI Xiaowei National Computer Network Intrusion Protection Center University of Chinese Academy of Sciences State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of Sciences

Key exchange protocols using both smart card and password are widely used nowadays since they provide greater convenience and stronger security than protocols using only a *** of these protocols are often limited to simple network systems,and they may have security *** propose a general construction for key exchange protocols using smart card and password to avoid these *** constructed protocol from the general construction has only one additional communication round than the original public encryption *** construction is proven secure under random oracle model,so it can resist several common types of *** is also adapted well to various *** with related protocols,the proposed key exchange protocol generated from the general construction has better secure properties and good computational efficiency in storage cost and operation time.

关键词： General construction Provable secure Smart card Password Key exchange protocol

New Superconvergent Structures with Optional Superconvergent Points for the Finite Volume Element Method

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Communications in Computational Physics 2023年第5期33卷 1332-1356页

作者： XiangWang yuqing zhang Zhimin zhang School of Mathematics Jilin UniversityChangchun 130012China Department of Mathematics Wayne State UniversityDetroitMI 48202USA

New superconvergent structures are proposed and analyzed for the finite volume element(FVE)method over tensorial meshes in general dimension d(for d≥2);we call these orthogonal superconvergent *** this framework,one has the freedom to choose the superconvergent points of tensorial k-order FVE schemes(for k≥3).This flexibility contrasts with the superconvergent points(such as Gauss points and Lobatto points)for current FE schemes and FVE schemes,which are *** orthogonality condition and the modified M-decomposition(MMD)technique that are developed over tensorial meshes help in the construction of proper superclose functions for the FVE solutions and in ensuring the new superconvergence properties of the FVE *** experiments are provided to validate our theoretical results.

关键词： Superconvergence finite volume orthogonality condition tensorial mesh rectangular mesh

Novel Ship Propulsion System

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Chinese Journal of Mechanical Engineering 2009年第2期22卷 198-206页

作者： JI Yulong SUN yuqing zhang Hongpeng zhang Yindong CHEN Haiquan School of Marine Engineering Dalian Maritime University Dalian 116026 China

As the development tends towards high-speed, large-scale and high-power, power of the ship main engine becomes larger and larger. This make the engine design and cabin arrangement become more and more difficult. Ship maneuverability becomes bad. A new ship propulsion system, integrated hydraulic propulsion （IHP）, is put forward to meet the development of modem ship. Principle of IHP system is discussed. Working condition matching characteristic of IHP ship is studied based on its matching characteristic charts. According to their propulsion principle, dynamic mathematic models of IHP ship and direct propulsion （DP） ship are developed. These two models are verified by test sailing and test stand data. Based on the software Matlab/Simulink, comparison research between IHP ship and DP ship is conducted. The results show that cabin arrangement of IHP ship is very flexible, working condition matching characteristic of IHP ship is good, the ratio of power to weight of IHP ship is larger than DP ship, and maneuverability is excellent. IHP system is suitable for engineering ship, superpower ship and warship, etc.

关键词： ship integrated hydraulic propulsion (IHP) ship propulsion system modeling and simulation working condition matching characteristic

Secure Multi-keyword Search Supporting Dynamic Update and Ranked Retrieval

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China Communications 2016年第10期13卷 209-221页

作者： Jingbo Yan yuqing zhang Xuefeng Liu State Key Laboratory of Integrated Services Networks Xidian University National Computer Network Intrusion Protection Center University of Chinese Academy of Sciences

As cloud computing is becoming prevalent, data owners are motivated to delegate complex data managements to the commercial cloud for economic savings. Sensitive data is usually encrypted before being uploaded to the cloud, which unfortunately makes the frequently-used search function a challenging problem. In this paper, we present a new multi-keyword dynamic search scheme with result ranking to make search over encrypted data more secure and practical. In the scheme, we employ a powerful function-hiding inner product encryption to enhance the security by preventing the leakage of search pattern. For the concern of efficiency, we adopt a tree-based index structure to facilitate the searching process and updating operations. A comprehensive security analysis is provided and experiments over the real world data show that our scheme is efficient.

关键词： secure search ranked search dynamic update cloud computing

XAS:Cross-API scripting attacks in social ecosystems

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Science China(Information Sciences) 2015年第1期58卷 42-55页

作者： zhang yuqing LIU QiXu LUO QiHan WANG XiaLi National Computer Network Intrusion Protection Center University of Chinese Academy of Sciences

With the rapid development of online social networks, various Web application programming interfaces(APIs) on social platforms are released to share profitable social data with all kinds of third-party online services. However, it also brings new risks to social networks once Web APIs are insecurely designed,implemented, and invoked. The focused topic in this paper is security analysis of a new type of cross-site scripting(XSS) which is based on Web APIs in new complicated social ecosystems which consist of social networks,third-party apps, and other online services. In this paper, we refer to Web API-based XSS as cross-API scripting(XAS). For the first time, we take typical XAS attacks in diversified context as cases to demonstrate the new exploiting opportunities and threats in social ecosystems. Also, we design a tool to identify the design and implementation flaws of Web APIs in 11 popular social networks. We discover several security flaws of API via our experiment. According to the results, we conclude causes of XAS flaws in depth. We also examined 143Web-based apps and verified the prevalence of XAS flaws. Finally, we proposed preliminary measures both in social networks and third-party applications to alleviate XAS.

关键词： Web security social network Web APIs cross-API scripting cross-site scripting

Authenticated Quantum Dialogue Without Information Leakage

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Chinese Journal of Electronics 2018年第2期27卷 270-275页

作者： WANG He zhang yuqing WU Gaofei MA Hua The State Key Laboratory of Integrated Services Networks Xidian University National Computer Network Intrusion Protection Center University of Chinese Academy of Sciences School of Mathematics and Statistics Xidian University

A lot of authenticated quantum dialogue protocols are springing up. Many of them have the problem of information leakage, or suffer from Man-In-TheMiddle attack. Some protocols can guarantee security, but have relatively low efficiency. Based on the above situation, we present a novel authenticated quantum dialogue protocol by using Bell states and entanglement *** this protocol, we adopt Einstein-Podolsky-Rosen(EPR)pairs to detect eavesdropping and transmit secret messages. We employ polarized photons to achieve authentication of users’ identity information. Compared with other quantum dialogue schemes with authentication, our protocol has several advantages. The transmitted particles are passed once and do not carry any secret messages. The proposed protocol can overcome the drawback of information leakage and resist against typical attacks. The efficiency is acceptable.

关键词： Quantum dialogue Bell states Authentication Entanglement swapping

Sedimentary microfacies of the H8 member in the Su14 3D seismic test area

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Mining Science and Technology 2011年第2期21卷 233-237页

作者： zhang yuqing Wang Zhizhang Resources and Information Institute China University of Petroleum Beijing 10224g China

The distribution of sedimentary microfacies in the eighth member of the Shihezi formation（the H8 member） in the Sul4 3D seismic test area was investigated.A Support Vector Machine（SVM） model was introduced for the first time as a way of predicting sandstone thickness in the study *** model was constructed by analysis and optimization of measured seismic *** distribution of the sedimentary microfacies in the study area was determined from predicted sandstone thickness and an analysis of sedimentary characteristics of the *** results indicate that sandstone thickness predictions in the study area using an SVM method are *** distribution of the sedimentary microfacies in the study area has been depicted at a fine scale.

关键词： SVM Seismic attribute Sandstone thickness Sedimentary microfacies 3D seismic test area