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A Hybrid Entropy and Blockchain Approach for Network Security Defense in SDN-Based IIoT

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Chinese Journal of Electronics 2023年第3期32卷 531-541页

作者： SU jian jiang Mengnan School of Computer Science Nanjing University of Information Science and Technology

In the industrial Internet of things(IIoT), various applications generate a large number of interactions and are vulnerable to various attacks, which are difficult to be monitored in a sophisticated way by traditional network architectures. Therefore, deploying software-defined network(SDN) in IIoT is essential to defend against various attacks. However, SDN has a drawback: there is a security problem of distributed denial-ofservice(DDoS) attacks at the control layer. This paper proposes an effective solution: DDoS detection within the domain using tri-entropy in information theory. The detected attacks are then uploaded to a smart contract in the blockchain, so that the attacks can be quickly cut off even if the same attack occurs in different domains. Experimental validation was conducted under different attack strengths and multiple identical attacks, and the results show that the method has better detection ability under different attack strengths and can quickly block the same attacks.

关键词： Smart contracts Network security Network architecture Denial-of-service attack Entropy Blockchains Software defined networking

Speech Magnitude Spectrum Reconstruction from MFCCs Using Deep Neural Network

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Chinese Journal of Electronics 2018年第2期27卷 393-398页

作者： jiang wenbin LIU Peilin wen Fei Department of Electronic Engineering Shanghai Jiao Tong University Air Control and Navigation Institution Air Force Engineering University

This work proposes a Deep neural network(DNN) based method for reconstructing speech magnitude spectrum from Mel-frequency cepstral coefficients(MFCCs). We train a DNN using MFCC vectors as input and the corresponding speech magnitude spectrum as desired output. Exploiting the strong inference power of DNN, the proposed method has the capability to accurately estimate the speech magnitude spectrum even from truncated MFCC vectors. Experiments on TIMIT corpus demonstrate that the proposed method achieves significantly better performance compared with traditional methods.

关键词： Deep neural network(DNN) Mel-frequency cepstral coefficients(MFCCs) Spectrum reconstruction Speech reconstruction

Carbon nanofibers embedded with Fe-Co alloy nanoparticles via electrospinning as lightweight high-performance electromagnetic wave absorbers

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Rare Metals 2024年第6期43卷 2769-2783页

作者： wen-Jun Cai jian-Guo jiang Zi-Dong Zhang Zi-Xuan Liu Lu-JieZhang Zhen-Kun Long Ke Bi Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJinan 250061China School of Materials Science and Engineering Shandong UniversityJinan 250061China Energy Institute Qilu University of Technology(Shandong Academy of Sciences)Jinan 250014China State Key Laboratory of Information Photonics and Optical Communications School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China

As a lot of electromagnetic pollution and interference issues have emerged,to overcome electromagnetic interference,prevent electromagnetic hazards,and develop new high-performance electromagnetic wave(EMW)absorbers have become a significant task in the field of materials *** this paper,a three-dimensional(3D)carbon nanofibers network with core-shell structure,embedded with varied molar ratios of iron and cobalt(4:0,3:1,2:2,1:3,0:4),was effectively synthesized(Fe/Co@C-CNFs)via *** phase,microstructure,magnetic and EMW absorption properties were *** is discovered that Fe/Co@C-CNFs doped with iron:cobalt=1:1 have excellent EMW absorption *** the matching thickness is 1.08 mm,the minimum reflection loss(RL)value is-18.66 dB,while the maximum effective absorption bandwidth(EAB)reaches 4.2 GHz(13.9-18 GHz)at a thickness of 1.22 *** is owing to the absorbers'superior impedance matching and multiple reflections as well as the conductivity,dielectric,and magnetic losses of carbon nanofibers embedded with Fe-Co alloy *** addition,the radar cross section(RCS)of the absorbers has been calculated by CST Studio Suite,showing that the absorbing coating can effectively reduce the RCS at various angles,especially for Fe/Co@C-CNFs doped with iron:cobalt=1:*** findings not only provide new insights for the preparation of light-weight and high-performance electromagnetic wave absorbers,but also contribute to energy storage and conversion.

关键词： Electromagnetic wave(EMW)absorbers Fe/Co@C-CNFs Core-shell structure EMW absorbing mechanism Radar cross section(RCS)

Effects of interfacial wettability on arc erosion behavior of Zn_(2)SnO_(4)/Cu electrical contacts

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Journal of Materials Science & Technology 2022年第14期109卷 64-75页

作者： Wei-jian Li Zi-Yao Chen Hao jiang Xiao-Han Sui Cong-Fei Zhao Liang Zhen wen-Zhu Shao School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China College of Nuclear Equipment and Nuclear Engineering Yantai UniversityYantai 264005China National Key Laboratory of Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China

Interface wettability is a vital role in directly impacting the electrical contact characteristics of oxides/Cubased composites under arc *** its influence mechanism,especially at atomic/electronic scales,is significant but challenging for the rational design of oxides/Cu ***,we designed Zn_(2)SnO_(4)/Cu electrical contacts aiming to solve the poor wettability of SnO_(2)/Cu *** was found that Zn_(2)SnO_(4)could remarkably improve the arc resistance of Cu-based electrical contacts,which was benefited by the excellent interface wettability of Zn_(2)SnO_(4)/*** characterization of eroded surface indicated that Zn_(2)SnO_(4)particles distributed uniformly on the contact surface,leading to stable electrical contact ***,SnO_(2)considerably deteriorated the arc resistance of SnO_(2)/Cu composite by agglomerating on the *** effect mechanism of wettability on arc resistance was investigated through density function theory(DFT)*** revealed that strong polar covalent bonds across the Zn_(2)SnO_(4)/Cu interface contributed to improving the interfacial adhesion strength/wettability and thus significantly enhanced the arc *** binary SnO_(2)/Cu interface,ionic bonds resulted in weak interface adhesion,giving rise to deterioration of electrical contact *** work discloses the bonding mechanism of oxide/Cu interfaces and paves an avenue for the rational design of ternary oxide/Cu-based electrical contact materials.

关键词： Zn_(2)SnO_(4)/Cu electrical contacts Arc erosion Wettability DFT calculations Electronic structure

Integrated classification method of tight sandstone reservoir based on principal component analysise simulated annealing genetic algorithmefuzzy cluster means

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Petroleum Science 2023年第5期20卷 2747-2758页

作者： Bo-Han Wu Ran-Hong Xie Li-Zhi Xiao jiang-Feng Guo Guo-wen Jin jian-Wei Fu National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

In this research,an integrated classification method based on principal component analysis-simulated annealing genetic algorithm-fuzzy cluster means(PCA-SAGA-FCM)was proposed for the unsupervised classification of tight sandstone reservoirs which lack the prior information and core experiments.A variety of evaluation parameters were selected,including lithology characteristic parameters,poro-permeability quality characteristic parameters,engineering quality characteristic parameters,and pore structure characteristic *** PCA was used to reduce the dimension of the evaluation pa-rameters,and the low-dimensional data was used as *** unsupervised reservoir classification of tight sandstone reservoir was carried out by the SAGA-FCM,the characteristics of reservoir at different categories were analyzed and compared with the lithological *** analysis results of numerical simulation and actual logging data show that:1)compared with FCM algorithm,SAGA-FCM has stronger stability and higher accuracy;2)the proposed method can cluster the reservoir flexibly and effectively according to the degree of membership;3)the results of reservoir integrated classification match well with the lithologic profle,which demonstrates the reliability of the classification method.

关键词： Tight sandstone Integrated reservoir classification Principal component analysis Simulated annealing genetic algorithm Fuzzy cluster means

Health Education in the Healthy China Initiative 2019−2030

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China CDC weekly 2021年第4期3卷 78-80页

作者： Zhuojun jiang wen jiang Media Integration and Mass Communication Department China Population Communication CenterBeijingChina

As the first of 15 Healthy China initiatives,the Health Education Initiative has the crucially important goal of improving citizens’health *** are two key activities in the initiative for improving health *** first is to establish a mechanism for dissemination of health sciences knowledge through development of national and provincial databases of health sciences expertise and a national resource of accessible health *** second is to establish a health education and health promotion performance evaluation mechanism for medical institutions and medical *** this paper,we analyzed the content and strategies of these two health educational activities.

关键词： promotion education knowledge

Global interpolating meshless shape function based on generalized moving least-square for structural dynamic analysis

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Applied Mathematics and Mechanics(English Edition) 2016年第9期37卷 1153-1176页

作者： Dan XIE Kailin jian Weibin wen College of Aerospace Engineering Chongqing University State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing University College of Engineering Peking University

A global interpolating meshless shape function based on the generalized moving least-square （GMLS） is formulated by the transformation technique. Both the shape function and its derivatives meet the Kronecker delta function property. With the interpolating GMLS （IGMLS） shape function, an improved element-free Galerkin （EFG） method is proposed for the structural dynamic analysis. Compared with the conven- tional EFG method, the obvious advantage of the proposed method is that the essential boundary conditions including both displacements and derivatives can be imposed by the straightforward way. Meanwhile, it can greatly improve the ill-condition feature of the standard GMLS approximation, and provide good accuracy at low cost. The dynamic analyses of the Euler beam and Kirchhoff plate are performed to demonstrate the feasi- bility and effectiveness of the improved method. The comparison between the numerical results of the conventional method and the improved method shows that the proposed method has better stability, higher accuracy, and less time consumption.

关键词： structural dynamics meshless method element-free Galerkin (EFG)method generalized moving least-square (GMLS)

Distribution of reformed coke oven gas in a shaft furnace

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Journal of Iron and Steel Research International 2020年第12期27卷 1382-1390页

作者： Xin jiang Jia-xin Yu Lin Wang Dong-wen Xiang Qiang-jian Gao Hai-yan Zheng Feng-man Shen School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina Department of Mechanical Engineering Shenyang Institute of EngineeringShenyang 110136LiaoningChina

In recent years, the reformed coke oven gas (COG) was proposed to be used as reducing gas in a shaft furnace. A mathematical model of gas flow based on the reformed COG was built. The effects of the pressure ratio of reducing gas to cooling gas (k) on the gas distribution in the shaft furnace were investigated. The calculation results show that k is an important operation parameter, which can obviously affect the gas distribution in the shaft furnace. The value of k should be compromised. Both too big and too small k values are not appropriate, and the most reasonable value for k is 1:*** this condition, the utilization coefficient of reducing gas, the utilization coefficient of cooling gas and the coefficient of upward gas are 0.94, 0.92 and 1.03, respectively. Based on the validation of physical experiments, the calculated values of the model agreed well with the physical experimental data. Thus, the established model can properly describe the reformed COG distribution in an actual shaft furnace.

关键词： Direct reduction Shaft furnace Coke oven gas Gas distribution Pressure ratio Reducing gas Cooling gas

Study on pyrolysis and gasification of wood in MSW

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Journal of Environmental Sciences 2006年第2期18卷 407-415页

作者： NI Ming-jiang XIAO Gang CHI Yong YAN jian-hua MIAO Qi ZHU wen-li CEN Ke-fa Institute for Thermal Power Engineering State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

In order to develop municipal solid waste（MSW） pyrolysis/gasification and melting technology with low emission and high efficiency, it was planed that all the main components in MSW and some typical kinds of MSW were pyrolyzed/gasified to propose an expert system for raw MSW. In this paper, wood, which was a prevalent component in MSW, was pyrolyzed and gasified in fluidized-bed reactors at different apparent excess air ratios （EARs）, temperatures and fluidizing velocities. For pyrolysis, with tem- perature increasing from 400℃ to 700℃, the yield of pyrolysis char decreased while that of pyrolysis gas increased （in this paper respectively from 28% to 20% and from 10% to 35%）, and when temperature was 500℃, the yield of pyrolysis tar reached the highest, up to 38% in this paper. It was the optimum for gasification when temperature was 600℃ and apparent EAR was 0.4. Under the experimental conditions of this paper, gasification efficiency achieved 73%, lower heat value（LHV） reached 5800 kJ/（Nm^3） and yield of syngas was 2.01 Nm^3/kg. Lower fluidizing velocity was useful to upgrade gasification efficiency and LHV of syngas for wood gasification. Based on the results, the reactive courses and mechanism were analyzed respectively for wood pyrolysis and gasification.

关键词： wood pyrolysis gasification municipal solid waste(MSW)