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SIV:A Structural Integrity Verification Approach of Cloud Components with Enhanced Privacy

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Tsinghua Science and Technology 2019年第5期24卷 557-574页

作者： Bo Zhao Peiru Fan Pengyuan Zhao mingtao ni Jinhui Liu School of Cyber Scienee and Engineering. Wuhan University Wuhan 430072 China. School of Computer Science Shaanxi Normal University Xi'an 710062 China

Private data leakage is a threat to current integrity verification schemes of cloud components. To address this issue, this work proposes a privacy-enhancing Structural Integrity Verification (SIV) approach. It is made up of three processes: proof organization, proof transformation, and integrity judgement. By introducing a merkle tree technique, the integrity of a constituent part of a cloud component on a node is represented by a root value. The value is then masked to cipher texts in proof transformation. With the masked proofs, a structural feature is extracted and validated in an integrity judgement by a third-party verification provider. The integrity of the cloud component is visually displayed in the output result matrix. If there are abnormities, the corrupted constituent parts can be located. Integrity is verified through the encrypted masked proofs. All raw proofs containing sensitive information stay on their original nodes, thus m.nimizing the attack surface of the proof data, and eliminating the risk of leaking private data at the source. Although some computations are added, the experimental results show that the time overhead is within acceptable bounds.

关键词： integrity verification cloud components structural feature privacy

Two Improvements on Numerical Simulation of 2-DOF Vortex-Induced Vibration with Low mass Ratio

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China Ocean Engineering 2017年第6期31卷 764-772页

作者： KANG Zhuang ni Wen-chi ZHANG Xu SUN Li-ping Deepwater Engineering Research Center Harbin Engineering University Harbin 150001 China

Till now, there have been lots of researches on numerical simulation of vortex-induced vibration. Acceptable results have been obtained for fixed cylinders with low Reynolds number. However, for responses of 2-DOF vortex-induced vibration with low mass ratio, the accuracy is not satisfactory, especially for the maximum amplitudes. In Jauvtis and Williamson＇s work, the maximum amplitude of the cylinder with low mass ratio m＊=2.6 can reach as large as 1.5D to be called as the ＂super-upper branch＂, but from current literatures, few simulation results can achieve such value, even fail to capture the upper branch. Besides, it is found that the amplitude decays too fast in the lower branch with the RANS-based turbulence model. The reason is likely to be the defects of the turbulence model itself in the prediction of unsteady separated flows as well as the unreasonable setting of the numerical simulation parameters. Aiming at above issues, a modified turbulence model is proposed in this paper, and the effect of the acceleration of flow field on the response of vortex-induced vibration is studied based on OpenFOAm. By analyzing the responses of amplitude, phase and trajectory, frequency and vortex mode, it is proved that the vortex-induced vibration can be predicted accurately with the modified turbulence model under appropriate flow field acceleration.

关键词： 2-DOF vortex-induced vibration numerical simulation modified turbulence model acceleration

Efficient degradation of orange II by Znmn2O4 in a novel photo-chemical catalysis system

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Frontiers of Chemical Science and Engineering 2020年第6期14卷 956-966页

作者： Qingzhuo ni Hao Cheng Jianfeng ma Yong Kong Sridhar Komarneni School of Environmental and Safety Engineering Changzhou UniversityChangzhou 213164China Guangxi Key Laboratory of Green Processing of Sugar Resources College of Biological and Chemical EngineeringGuangxi Science University of and TechnologyLiuzhou 545006China Jiangsu Key Laboratory of Oil-Gas Storage and Transportation Technology Changzhou UniversityChangzhou 213164China Department of Ecosystem Science and management and materials Research Institute The Pennsylvania State UniversityUniversity ParkPA 16802USA

A Znmn2O4 catalyst has been synthesized via a sucrose-aided combustion method and characterized by various analytical *** is composed of numerous nanoparticles(15-110 nm)assembled into a porous structure with a specific surface area(SSA)o f 19.1 m^2.g^-*** catalytic activity has been investigated for the degradation of orange II dye using three different systems,i.e.,the photocatalysis system with visible light,the chemocatalysis system with bisulfite,and the photochemical catalysis system with both visible light and *** last system exhibits the maximum degradation efficiency of 90%,much higher than the photocatalysis system(15%)and the chemocatalysis system(67%).The recycling experiments indicate that the Znmn204 catalyst has high stability and reusability and is thus a green and eximious ***,the potential degradation mechanisms applicable to the three systems are discussed with relevant theoretical analysis and scavenging experiments for *** active species such as mn(III),o2^-,H^+,eaq,So4^- and Ho^-are proposed to be responsible for the excellent degradation results in the photo-chemical catalysis system with the Znmn2o4 catalyst.

关键词： Znmn2O4 photo-chemical catalysis bisulfite dye degradation

Semi-Homogenous Generalization： Improving Homogenous Generalization for Privacy Preservation in Cloud Computing

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Journal of Computer Science & Technology 2016年第6期31卷 1124-1135页

作者： Xian-mang He Xiaoyang SeanWang Dong Li Yan-ni Hao School of Information Science and Engineering Ningbo University Ningbo 315211 China School of Computer Science Fudan University Shanghai 200433 China Information Center National Natural Science Foundation of China Beijing 100085 China

Data security is one of the leading concerns and primary challenges for cloud computing. This issue is getting more and more serious with the development of cloud computing. However, the existing privacy-preserving data sharing techniques either fail to prevent the leakage of privacy or incur huge amounts of information loss. In this paper, we propose a novel technique, termed as linking-based anonymity model, which achieves K-anonymity with quasi-identifiers groups （QI-groups） having a size less than K. In the meanwhile, a semi-homogenous generalization is introduced to be against the attack incurred by homogenous generalization. To implement linking-based anonymization model, we propose a simple yet efficient heuristic local recoding method. Extensive experiments on real datasets are also conducted to show that the utility has been significantly improved by our approach compared with the state-of-the-art methods.

关键词： privacy preservation cloud computing linking-based anonymization semi-homogenous homogenous generalization

Recovery of iron from copper slag by deep reduction and magnetic beneficiation

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International Journal of minerals,metallurgy and materials 2013年第11期20卷 1035-1041页

作者： Ke-qing Li Shuo Ping Hong-yu Wang Wen ni Key Laboratory of the m.nistry of Education of China for High-Efcient m.ning and Safety of metal mines University of Science and Technology Beijing School of Civil and Environmental Engineering University of Science and Technology Beijing

Aiming at recovering iron from high-iron-content copper slag, this article introduced a combination technol- ogy of deep reduction and magnetic beneficiation, investigated the iron recovery efficiency and optimized the technical conditions. When coke powder with 86wt% fixed carbon was used as a reductant, iron was successfully extracted from the copper slag. Under the optimized condition of the coke powder content of 14wt%, the calcium-to-silicon mass ratio （Ca/Si） of 0.2, the roasting temperature of 1300℃, the roasting time of 3 h, the grinding time of 20 min, and the magnetic field intensity of 61 kA-m-1, the iron recovery rate of the copper slag can reach 91.82%, and the extracted iron powder has an iron grade of 96.21%. With the characteristics of high iron grade and low impurity content, the extracted iron powder can be used as high-quality raw materials of weathering steel.

关键词： copper slag waste utilization ore reduction magnetic separation beneficiation

There is life after coking for Ir nanocatalyst superlattices

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Nano Research 2022年第8期15卷 6969-6976页

作者： Antonio J.martínez-Galera Haojie Guo mariano D.Jiménez-Sánchez Stefano Franchi Kevin C.prince José m.Gómez-Rodríguez Departamento de Física de la materia Condensada Universidad Autónoma de MadridMadrid E-28049Spain Instituto nicolás Cabrera Universidad Autónoma de MadridMadrid E-28049Spain Elettra-Sincrotrone Trieste S.C.p.A. in Area Science ParkBasovizza(Trieste)34149Italy Condensed matter Physics Center(IFImAC) Universidad Autónoma de MadridMadrid E-28049Spain

Achieving superior performance of nanoparticle systems is one of the biggest challenges in *** major phenomena,occurring during the reactions,hinder the development of the full potential of nanoparticle catalysts:sintering and contamination with carbon containing species,sometimes called ***,we demonstrate that Ir nanocrystals,arranged into periodic networks on hexagonal boron nitride(h-BN)supports,can be restored without sintering after contamination by persistent *** restoration yields the complete removal of carbon from the nanocrystals,which keep their crystalline structure,allowing operation without *** findings,together with the possibility of fine tuning the nanocrystals size,confer this nanoparticle system a great potential as a testbed to extract key information about catalysis-mediated oxidation *** the case of the CO oxidation by O2,reaction of interest in environmental science and green energy production,the existence of chemical processes not observed before in other nanoparticle systems is demonstrated.

关键词： catalysis coke nanoparticles scanning tunneling microscopy(STm) X-ray photoemission spectroscopy(XPS)

Translating Surfaces of the Non-parametric mean Curvature Flow in Lorentz m.nifold m^(2)×R^(*)

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Chinese Annals of mathematics,Series B 2021年第2期42卷 297-310页

作者： Li CHEN Dan-Dan HU Jing mAO ni XIANG Faculty of mathematics and Statistics Key Laboratory of Applied Mathematics of Hubei ProvinceHubei UniversityWuhan 430062China

In this paper, for the Lorentz m.nifold m^(2)× R with m^(2) a 2-dimensional complete surface with nonnegative Gaussian curvature, the authors investigate its spacelike graphs over compact, strictly convex domains in m^(2), which are evolving by the nonparametric mean curvature flow with prescribed contact angle boundary condition, and show that solutions converge to ones moving only by translation.

关键词： Translating surfaces mean curvature flow Lorentz m.nifolds

Thermal conductivity prediction of mgAl2O4:a non-equilibrium molecular dynamics calculation

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Journal of Iron and Steel Research International 2020年第5期27卷 500-505页

作者： Cheng-ming ni Hua-wei Fan Xu-dong Wang man Yao School of materials Science and Engineering Dalian University of TechnologyDalian 116000LiaoningChina

magnesium aluminate spinel(mgAl2O4)is widely used in steel metallurgy *** conductivity at high temperature signifcantly infuences the cooling process of blast furnace and the heat preservation of steel *** efect of external(temperature)and internal(antisite defect and grain boundary)factors on the thermal conductivity of mgAl2O4 was studied with non-equilibrium molecular *** main factors afecting the thermal conductivity of mgAl2O4 were *** the temperature range of 100-2000 K,the results showed that the thermal conductivity of mgAl2O4 changed from 11.54 to 4.95 W/(m K)with the increase in temperature and was relatively stable at the temperature above 1000 *** thermal conductivity of mgAl2O4 declined frst and then rose with the increase in the antisite defects,and the m.nimum value was 6.95 W/(m K)at the inversion parameter i=*** addition,grain boundaries reduced the thermal conductivity of mgAl2O4 by 20%-30%at temperature below 1000 K comparing with the non-grain boundary *** grain boundary rotation angle at temperature above 1000 K had less efect on the thermal conductivity than that below 1000 *** simulation scheme for thermal conductivity of mgAl2O4 can also be applied to the study of other nonmetallic ceramics.

关键词： Non-equilibrium molecular dynamics Thermal conductivity magnesium aluminate spinel Antisite defect Grain boundary

Uncertainty propagation analysis by an extended sparse grid technique

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Frontiers of mechanical Engineering 2019年第1期14卷 33-46页

作者： X.Y.JIA C.JIANG C.m.FU B.Y.ni C.S.WANG m.H.PING State Key Laboratory of Advanced Design and manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China Key Laboratory of Electronic Equipment Structure Design ofm.nistry of Education School of Electro-Mechanical EngineeringXidian UniversityXi'an 710071China

In this paper,an uncertainty propagation analysis method is developed based on an extended sparse grid technique and maximum entropy principle,aiming at improving the solving accuracy of the high-order moments and hence the fitting accuracy of the probability density function(PDF)of the system *** proposed method incorporates the extended Gauss integration into the uncertainty propagation ***,assisted by the Rosenblatt transformation,the various types of extended integration points are transformed into the extended Gauss-Hermite integration points,which makes the method suitable for any type of continuous ***,within the sparse grid numerical integration framework,the statistical moments of the system response are obtained based on the transformed ***,based on the maximum entropy principle,the obtained first four-order statistical moments are used to fit the PDF of the system ***,three numerical examples are investigated to demonstrate the effectiveness of the proposed method,which includes two mathematical problems with explicit expressions and an engineering application with a black-box model.

关键词： uncertainty propagation analysis extended sparse grid maximum entropy principle extended Gauss integration Rosenblatt transformation high-order moments analysis