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Adhesion Performances Between Two Orthotropic Solids Influenced by Temperature Increment

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Acta Mechanica Solida Sinica 2024年第3期37卷 430-443页

作者： Qing-hui luo Yue-Ting Zhou School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai200092China

The classical adhesive contact models belong to isothermal adhesion theories,where the effect of temperature on adhesion was ***,a number of experimental results indicated that the adhesion behaviors can be significantly affected by *** this paper,the two-dimensional non-slipping anisothermal adhesion behaviors between two orthotropic elastic cylinders are investigated within the framework of the Johnson-Kendall-Roberts *** stated problem is reduced to the coupled singular integral equations by virtue of the Fourier integral transform,which are solved analytically with the analytical function *** closed-form solutions for the stress fields in the presence of thermoelastic effect are *** stable equilibrium state of contact system is determined by virtue of the Griffith energy *** effect of temperature difference on adhesion behaviors between orthotropic solids is *** is found that the difference between the oscillatory and non-oscillatory solutions increases with increasing the degree of anisotropy of orthotropic *** oscillatory solution cannot be well approximated by the non-oscillatory solution for the orthotropic materials with relatively high anisotropy.

关键词： Adhesive contact Non-slipping JKR model Temperature Griffith energy balance

Quench sensitivity of Al-Cu-Mg alloy thick plate

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Rare Metals 2023年第9期42卷 3161-3169页

作者： Yuan Yin Bing-hui luo Zhen-Hai Bai hui-Bo Jing School of Materials Science and Engineering Central South UniversityChangsha410083China

The quench sensitivity of Al-Cu-Mg alloy was investigated at different thicknesses of the thick *** quenching process was simulated via finite element analysis(FEA);time-temperature-property(TTP)curves and time-temperature-transformation(TTT)curves were obtained through hardness test and differential scanning calorimetry(DSC)test;and the microstructural observation was carried out by scanning electron microscopy(SEM)and transmission electron microscopy(TEM).Experimental results exhibit that the quench cooling rate decreases dramatically from the surface to the center of the plate,and the inhomogeneous quenching causes the difference in *** the decrease in quench cooling rate,constituent particles are coarsening gradually;the quantity of T-phase(Al_(20)Cu_(2)Mn_(3))increases and the S-phase(Al_(2)Cu Mg)*** to the precipitation kinetics analysis,the decrease in S-phase is caused by the increase in precipitate activation *** that the center of the plate shows the highest quenching sensitivity,which is consistent with the analysis of time-temperature-property curves and time-temperature-transformation curves.

关键词： Al-Cu-Mg alloy Quench sensitivity Precipitation kinetics Time-temperature-property curves Microstructure

In-situ observations of dendritic fragmentation during directional solidification of Sn-10wt.% Bi alloy

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China Foundry 2019年第4期16卷 262-266页

作者： Ji-hui luo College of Materials Science and Engineering Yangtze Normal University

The stray crystals seriously affect the properties of metals which fabricated by directional solidification(DS). In order to observe the formation of the stray crystals, the growth behavior of Sn-10 wt.%Bi alloy was observed by synchrotron X-ray imaging technique using self-developed directional solidification(DS) apparatus. The experimental results show that Sn–10 wt.%Bi alloy is oriented with the form of dendrites to grow into the liquid phase during the DS process, and dendrites are arranged neatly to form columnar crystal microstructures. It is also found that parts of the dendrite arms begin to crack. These cracked dendrites drift upward to grow up in front of the solid-liquid interface and form stray crystals.

关键词： Sn-Bi alloy syn chrotr on X-ray radiography di recti onal solidification den dritic fragme ntation

Quark jet versus gluon jet: fully-connected neural networks with high-level features

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Science China(Physics,Mechanics & Astronomy) 2019年第9期62卷 49-59页

作者： hui luo Ming-Xing luo Kai Wang Tao Xu GuoHuai Zhu Graduate School of China Academy of Engineering Physics Beijing 100193China Zhejiang Institute of Modem Physics and Department of Physics Zhejiang UniversityHangzhou 310027China Institut fiir Theoretische Physik Universitat Hamburg Luruper Chaussee 149Hamburg D- 22761Germany

Jet identification is one of the fields in high energy physics that machine learning has begun to make an impact. More often than not, convolutional neural networks are used to classify jet images with the benefit that essentially no physics input is *** by a recent work by Datta and Larkoski, we study the classification of quark/gluon-initiated jets based on fully-connected neural networks(FNNs), where expert-designed physical variables are taken as input. FNNs are applied in two ways: trained separately on various narrow jet transverse momentum pTJbins;trained on a wide region of pTJ∈[200, 1000] GeV. We find their performances are almost the same. The performance is better when the pTJis larger. Jet discrimination with FNN is studied on both particle and detector level data. The results based on particle level data are comparable with those from deep convolutional neural networks, while the significance improvement characteristic(SIC) from detector level data would at most decrease by 15%.We also test the performance of FNNs with the full set or subsets of jet observables as input features. The FNN with one subset consisting of fourteen observables shows nearly no degradation of performance. This indicates that these fourteen expert-designed observables could have captured the most necessary information for separating quark and gluon jets.

关键词： standard model simulation quark-gluon jets machine learning

Aircraft engine fault detection based on grouped convolutional denoising autoencoders

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Chinese Journal of Aeronautics 2019年第2期32卷 296-307页

作者： Xuyun FU hui luo Shisheng ZHONG Lin LIN Department of Mechanical Engineering Harbin Institute of Technology at Weihai School of Mechatronics Engineering Harbin Institute of Technology

Many existing aircraft engine fault detection methods are highly dependent on performance deviation data that are provided by the original equipment manufacturer. To improve the independent engine fault detection ability, Aircraft Communications Addressing and Reporting System(ACARS) data can be used. However, owing to the characteristics of high dimension, complex correlations between parameters, and large noise content, it is difficult for existing methods to detect faults effectively by using ACARS data. To solve this problem, a novel engine fault detection method based on original ACARS data is proposed. First, inspired by computer vision methods, all variables were divided into separated groups according to their correlations. Then, an improved convolutional denoising autoencoder was used to extract the features of each group. Finally, all of the extracted features were fused to form feature vectors. Thereby, fault samples could be identified based on these feature vectors. Experiments were conducted to validate the effectiveness and efficiency of our method and other competing methods by considering real ACARS data as the data source. The results reveal the good performance of our method with regard to comprehensive fault detection and robustness. Additionally, the computational and time costs of our method are shown to be relatively low.

关键词： Aircraft engines Anomaly detection Convolutional Neural Network(CNN) Denoising autoencoder Engine health management Fault detection

A Privacy-Preserving Federated Learning Algorithm for Intelligent Inspection in Pumped Storage Power Station

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China Communications 2023年第12期20卷 182-195页

作者： Yue Zong Yuanlin luo YuechaoWu Wenjian Hu hui luo Yao Yu Power China Huadong Engineering Corporation Limited HangzhouZhejiang 311122China School of Computer Science and Engineering Northeastern UniversityShenyangLiaoning 110819China

As a distributed machine learning architecture,Federated Learning(FL)can train a global model by exchanging users’model parameters without their local ***,with the evolution of eavesdropping techniques,attackers can infer information related to users’local data with the intercepted model parameters,resulting in privacy leakage and hindering the application of FL in smart *** meet the privacy protection needs of the intelligent inspection task in pumped storage power stations,in this paper we propose a novel privacy-preserving FL algorithm based on multi-key Fully Homomorphic Encryption(FHE),called ***,to reduce communication costs caused by deploying the FHE algorithm,we propose a self-adaptive threshold-based model parameter compression(SATMPC)*** can reduce the amount of encrypted data with an adaptive thresholds-enabled user selection mechanism that only enables eligible devices to communicate with the FL ***,to protect model parameter privacy during transmission,we develop a secret sharing-based multi-key RNS-CKKS(SSMR)method that encrypts the device’s uploaded parameter increments and supports decryption in device dropout *** analyses and simulation results show that our algorithm can prevent four typical threat models and outperforms the state-of-the-art in communication costs with guaranteed accuracy.

关键词： federated learning(FL) fully homomorphic encryption(FHE) intelligent inspection multikey RNS-CKKS parameter compression

Possibility of using strain F9(Serratia marcescens) as a bio-collector for hematite flotation

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International Journal of Minerals,Metallurgy and Materials 2014年第3期21卷 210-215页

作者： hui-fen Yang Tian Li Yan-hong Chang hui luo Qiong-yao Tang Civil and Environmental Engineering School University of Science and Technology Beijing State Key Laboratory for High-Efficiency Mining and Safety of Metal Mines Ministry of Education

In this study, we characterized strain F9 and evaluated the interaction between strain F9 and hematite by scanning electron microscopy（SEM）, Fourier transform infrared spectrophotometry（FTIR）, zeta potential, flotation, and other methods. The results showed that strain F9 belongs to Serratia marcescens. This brevibacterium had CH2, CH3, and hydroxyl groups on its cell wall, which imparted a strong hydrophobic and negative charge. Adsorption of strain F9 reduced the zeta potential of the hematite surface and increased the hydrophobicity of the hematite surface, thereby generating hydrophobic hematite agglomerates. At least four groups on strain F9 interacted with the hematite surface, which contributed to chemical interactions of carboxylic groups and hydrophobic association among hydrophobic hematite particles. The possible use of strain F9 as a bio-collector for hematite flotation was proved.

关键词： microorganisms Serratia marcescens flotation hydrophobicity hematite

Microstructure evolution and precipitation behavior of Al-Mg-Si alloy during initial aging

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China Foundry 2023年第1期20卷 57-62页

作者： Ya-ya Zheng Bing-hui luo Wei Xie Wang Li Department of Materials Engineering Hunan University of HumanitiesScience and TechnologyLoudi 417000HunanChina College of Materials Science and Engineering Central South UniversityChangsha 410083China Key Laboratory of Safety Design and Reliability Technology for Engineering Vehicle Changsha University of Science&TechnologyChangsha 410114China

The microstructure evolution and precipitation behavior of Al-Mg-Si alloy during initial aging were studied using hardness testing, conductivity testing, differential scanning calorimetry(DSC), and high resolution transmission electron microscopy(HRTEM). The results show that the precipitation sequence of the Al-Mg-Si alloy during initial aging can be represented as: supersaturated solid solution → spherical Mg/Si clusters → needle-like Guinier Preston(GP) zone → β″. Clusters are completely coherent with the Al matrix. The GP zone with relatively complete independent lattice parameters that differ slightly from the Al matrix parameters, is oriented along the direction of Aland lying on {111}Alplane. The strength of the Al-Mg-Si alloy is greatly enhanced by the threedimensional strain field that exists between the β″ phase and the two {200}Alplanes. After aging at 170 ℃ for 6 h, the hardness reaches the peak of 127 HV and remains for a long time. At this stage, the electrical conductivity keeps relatively stable due to the formation of coherent precipitates(Mg/Si clusters/GP zones) and the reduction in solute atom concentration in the Al matrix. The severe coarsening and decreased number density of the β″ phase during the over-aging stage result in a significant decrease in the hardness.

关键词： Al-Mg-Si alloy precipitation behavior strengthening mechanism strain field β″

Chinese herbal medicine for subacute thyroiditis:a systematic review of randomized controlled trials

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Journal of Traditional Chinese Medicine 2014年第3期34卷 243-253页

作者： hui luo Meng Lü Xiaohua Pei Zhongyuan Xia Institute for Tibetan Medicine ChinaTibetology ResearchCenter Sino-Japanese Friendship Clinical School of Medicine Beijing University of Chinese Medicine Department of Surgery Third Affiliated Hospital Beijing University of Chinese Medicine Department of Surgery of Traditional Chinese Medicine China-Japan Friendship Hospital

OBJECTIVE:To evaluate the effectiveness and safety of Chinese herbal medicine(CHM) in the ***: Randomized controlled trials found in PubMed, Cochrane Library, and three Chinese databases were selected. RevMan 5.2 software was used to analyze the data with relative risk or mean difference, expressed with 95% of confidence interval. The quality of trials was assessed and gradedthe quality of evidence with GRADE profiler ***: Twenty one studies were included. CHM was superior to Western Medicine(include prednisone and NSAIDs) in abating fever, relieving thyroid pain, recovering blood sedimentation, improving thyroid function, and preventing hypothyroidism(P0.05) were found in recovering blood sedimentation and improving thyroid function. The incidence of adverse reactions in treatment group was lower than that in control group(relative risk was 0.12 and 95% confidence interval was 0.03-0.51). The methodological quality of trials is generally poor with a high risk of ***: CHM(particularly CHM combined withWestern Medicine) used to treat subacute thyroiditis may improve clinical symptoms and signs,reduce relapse rate, and alleviate the side effects of hormones. Due to poor methodological quality of included trials, further more high-quality studies are warranted to confirm the effectiveness and safety of CHM.

关键词： Drugs, Chinese herbal Thyroiditis, sub-acute Randomized controlled trial Review, system-atic