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T-PBFT: An EigenTrust-Based Practical Byzantine Fault Tolerance Consensus Algorithm

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China Communications 2019年第12期16卷 111-123页

作者： Sheng Gao Tianyu Yu jianming zhu Wei Cai School of Information Central University of Finance of EconomicsBeijing 100081China Grain Information Processing and Control Key Laboratory of Ministry of Education Henan University of TechnologyZhengzhou 450001China School of Science and Engineering The Chinese University of Hong KongShenzhen 518172China

Blockchain with these characteristics of decentralized structure, transparent and credible, time-series and immutability, has been considering as a promising technology. Consensus algorithm as one of the core techniques of blockchain directly affects the scalability of blockchain systems. Existing probabilistic finality blockchain consensus algorithms such as PoW, PoS, suffer from power consumptions and low efficiency;while absolute finality blockchain consensus algorithms such as PBFT, HoneyBadgerBFT, could not meet the scalability requirement in a largescale network. In this paper, we propose a novel optimized practical Byzantine fault tolerance consensus algorithm based on EigenTrust model, namely T-PBFT, which is a multi-stage consensus algorithm. It evaluates node trust by the transactions between nodes so that the high quality of nodes in the network will be selected to construct a consensus group. To reduce the probability of view change, we propose to replace a single primary node with a primary group. By group signature and mutual supervision, we can enhance the robustness of the primary group further. Finally, we analyze T-PBFT and compare it with the other Byzantine fault tolerant consensus algorithms. Theoretical analysis shows that our T-PBFT can optimize the Byzantine fault-tolerant rate,reduce the probability of view change and communication complexity.

关键词： blockchain consensus protocol Byzantine fault tolerance trust model

APRS: a privacy-preserving location-aware recommender system based on differentially private histogram

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Science China(Information Sciences) 2017年第11期60卷 297-306页

作者： Sheng GAO Xindi MA jianming zhu Jianfeng MA School of Information Central University of Finance and Economics School of Computer Science and Technology Xidian University School of Cyber Engineering Xidian University

Appendix A Preliminaries In this section,we present some preliminaries that server as the basis of *** convenience,the notations used in this paper are listed in Tabel A1.

关键词： a privacy-preserving location-aware recommender system based on differentially private histogram Si

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RYY++: A Novel Provably Secure Identity-Based Authenticated Key Agreement Protocol

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Chinese Journal of Electronics 2015年第2期24卷 332-337页

作者： LI Yang zhu jianming ZHANG Ning WANG Xiuli ZHANG Yaoqi College of Information Central University of Finance and Economics

Based on revisiting the RYY+Identitybased(ID-Based) key agreement protocol, we find it's vulnerable to Intermediate results leakage(IRL) and Keycompromise impersonation(KCI) attack. A novel protocol called RYY++is proposed to make up for its *** protocol follows the Full dual exponential challenge response(FDCR-1) scheme to ensure the signature change every time, so the master public key of Private key generator(PKG) joined in signature generation can guarantee two parties trust each other. The RYY++protocol is also proven to be secure in the Strengthened extended Canetti–Krawczyk(Se CK) model which provides better support for adversary's query and has an advantage over most existing protocols on security and efficiency.

关键词： Authenticated key agreement ID-based Provable security Se CK model

STRENGTH PROPERTIES OF JOINTED ROCK MASSES BASED ON THE HOMOGENIZATION METHOD

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Acta Mechanica Solida Sinica 2012年第2期25卷 177-185页

作者： Hongtao Zhang jianming zhu Yinghua Liu Bingye Xu Xiaochun Wang Department of Civil Engineering North China University of TechnologyBeijing 100144China Department of Engineering Mechanics Tsinghua UniversityBeijing 100084China

This paper aims to determine the strength properties of jointed rock masses by means of the homogenization method. To reflect the microstructure of jointed rock masses, a representative element volume （REV） is selected. Assuming being rigid and perfectly plastic and utilizing the Mohr-Coulomb yield criterion for rock and joints, an upper bound limit analysis method is proposed based on the homogenization theory. By using the finite element method and Goodman joint element, a nonlinear mathematical programming with equality constraints is formulated, which can be solved by a direct iterative algorithm. Numerical results show the strength of jointed rock masses behaves anisotropy with different joint directions. This method presents an effective tool for the strength analysis of jointed rock masses.

关键词： jointed rock mass homogenization representative element volume (REV) upperbound limit analysis anisotropy

Biomineralization of Se Nanoshpere by Bacillus Licheniformis

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Journal of Earth Science 2015年第2期26卷 246-250页

作者： Yongqiang Yuan jianming zhu Congqiang Liu Shen Yu Lei Lei State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Research Center for Urban Ecological Health and Environmental Safety Institute of Urban EnvironmentChinese Academy of Sciences Insititute of Earth Sciences China University of GeosciencesBeijing

Biological dissimilatory reduction of selenite （SeO3^2-） to elemental selenium （Se^0） is common, but the mineral formation and the biogenic process remain uncertain. In this study, we examined the Se^0 formation during the selenite bioreduction by Bacillus licheniformis SeRB-1 through transmission electron microscope （TEM）, energy-dispersive spectrometry （EDS） and X-ray absorption fine structure （XAFS） techniques. Results showed that the reduction process occurred mostly during the exponential phase and early stationary phase, whilst the elemental selenium was produced in these periods. From the TEM images and polyaerylamide gel eleetropheresis, it is known that the Se^0 granule formation is a biologically-induced type, and the cell envelopes are the main biomineralization positions, and particles may go through a process from nucleation to crystallization, under the control of microbes. In fact, the minerals are spherical nanoparticles, occurring as a microcrystal or amorphous form. It is vital to recognize which kinds of proteins and/or polysaccharides act as a template to direct nanoparticle nucleation and growth？ This should focus for further studies. This study may shed light on the process of formation of Se（0） nanosphere.

关键词： biomineralization genesis selenite reduction selenium nanosphere.

Investigation of high extraction efficiency flip-chip GaN-based light-emitting diodes

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Science in China(Series F) 2009年第8期52卷 1476-1482页

作者： DA XiaoLi SHEN GuangDi XU Chen ZOU DeShu zhu YanXu ZHANG jianming Institute of Electronic Information and Control Engineering Beijing Optoelectronic Technology Lab Beijing University of TechnologyBeijing 100124 China

In order to obtain higher light output power, the flip-chip structure is used. We studied the ratio of the light of GaN sides before and after fabricating metal reflector on p-GaN. The SiO2/SiNx dielectric film reflectors were deposited through plasma enhance chemical vapor deposition following the fabrication of metal reflector, and then the dielectric film reflectors on the electrodes were etched in order to expose the electrodes to the air. It is found that comparing with the flip-chip GaN-LED without dielectric film reflectors, light output power can be increased by as high as 10.2% after the deposition of 2 pairs of SiO2/SiNx dielectric film reflectors on GaN-LEDs, which cover the sidewalls and the areas without the metal reflector. This result indicates that the high reflector formed by multi-layer dielectric films is useful to enhance the light output power of GaN-based LED, which reflects light from step sidewalls and p-GaN without metal reflector to internal, and then light emits from the surface.

关键词： GaN light emitting diodes SiO2/SiN=dielectric film reflectors plasma enhanced chemical vapor deposition

Dynamic Intelligent Supply-Demand Adaptation Model Towards Intelligent Cloud Manufacturing

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Computers, Materials & Continua 2022年第8期72卷 2825-2843页

作者： Yanfei Sun Feng Qiao Wei Wang Bin Xu jianming zhu Romany Fouad Mansour Jin Qi School of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing210003China College of Automation&College of Artificial Intelligence Nanjing University of Posts and TelecommunicationsNanjing210003China Department of Mathematics Faculty of ScienceNew Valley UniversityEl-Karaga72511Egypt

As a new mode and means of smart manufacturing,smart cloud manufacturing(SCM)faces great challenges in massive supply and demand,dynamic resource collaboration and intelligent *** address the problem,this paper proposes an SCM-oriented dynamic supply-demand(SD)intelligent adaptation model for massive manufacturing *** this model,a collaborative network model is established based on the properties of both the supply-demand and their relationships;in addition,an algorithm based on deep graph clustering(DGC)and aligned sampling(AS)is used to divide and conquer the large adaptation domain to solve the problem of the slow computational speed caused by the high complexity of spatiotemporal search in the collaborative network *** the same time,an intelligent supply-demand adaptation method driven by the quality of service(QoS)is established,in which the experiences of adaptation are shared among adaptation subdomains through deep reinforcement learning(DRL)powered by a transfer mechanism to improve the poor adaptation results caused by dynamic *** results show that the model and the solution proposed in this paper can performcollaborative and intelligent supply-demand adaptation for themassive and dynamic resources in SCM through autonomous learning and can effectively performglobal supply-demand matching and optimal resource allocation.

关键词： Smart Cloud Manufacturing supply and demand sides dynamic adaptation Deep Graph Clustering transfer learning reinforcement learning

Ordering of Unicyclic Graphs with Perfect Matchings by Minimal Matching Energies

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Open Journal of Discrete Mathematics 2019年第1期9卷 17-32页

作者： jianming zhu Department of Applied Mathematics Shanghai University of International Business and Economics Shanghai China

In 2012, Gutman and Wagner proposed the concept of the matching energy of a graph and pointed out that its chemical applications can go back to the 1970s. The matching energy of a graph is defined as the sum of the absolute values of the zeros of its matching polynomial. Let u and v be the non-isolated vertices of the graphs G and H with the same order, respectively. Let wi?be a non-isolated vertex of graph Gi?where i=1, 2, …, k. We use Gu(k)?(respectively, Hv(k)) to denote the graph which is the coalescence of G (respectively, H) and G1, G2,…, Gk?by identifying the vertices u (respectively, v) and w1, w2,…, wk. In this paper, we first present a new technique of directly comparing the matching energies of Gu(k)?and Hv(k), which can tackle some quasi-order incomparable problems. As the applications of the technique, then we can determine the unicyclic graphs with perfect matchings of order 2n with the first to the ninth smallest matching energies for all n≥211.

关键词： Matching Energy Unicyclic Graph Perfect Matching

Non-linear Integer Programming Model and Algorithms for Connected p-facility Location Problem

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Journal of Systems Science and Information 2014年第5期2卷 451-460页

作者： jianming zhu College of Engineering and Information Technology University of Chinese Academy of Sciences

In this paper, a new location analysis method is presented. Given a connected graph G =(V, E) with nonnegative edge cost ce for each edge e ∈ E, dij is the cost of the shortest path between vertices i and j in the graph. The Connected p-facility Location Problem(Cp LP) is to choose p vertices from V so as to minimize the total cost of shortest path of pair-wise of these p *** problem is proved to be NP-hard and non-linear integer programming is formulated. Then, two algorithms are designed for solving the Cp LP. One is a heuristic algorithm based on classical maximum clique approach, while the second one is genetic algorithm. Finally, computational results show the comparison between these two algorithms.

关键词： connected location maximum clique heuristic algorithm genetic algorithm