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Friction 2021年第4期9卷 758-773页

作者： Cun-ao FENg De-kun ZHANg Kai CHEN School of Mechatronic Engineering China University of Mining and TechnologyXuzhou 221116China Department of Mechanical Engineering University of British Columbia Vancouver V6T1Z4Canada School of Materials Science and Engineering China University of Mining and Technology Xuzhou 221116China

The mechanism of adhesive friction between viscoelastic materials is a key *** this study,the friction process of the adhesive interface between a friction lining and a wire rope is dynamically observed in real time to analyze the adhesion hysteresis friction intuitively and *** adhesion is determined by the state of motion,while the relative displacement of the wire rope and lining is used to find the magnitude of the adhesive *** hysteresis friction is reflected by the internal deformation of the *** magnitude of the hysteresis friction is determined by the displacement difference(Ax)in the sliding direction of two marked points at different distances from the contact *** results show that the adhesion friction is proportional to the loss modulus and the hysteresis friction is proportional to the ratio of the loss modulus to the square of the storage modulus(E"/(E'^(2))).The frictional vibration first decreases and then increases with the increase in *** K25 lining has the highest adhesion hysteresis friction and minimal frictional *** result provides a simple and intuitive method for research into the friction transmission and vibration of viscoelastic materials.

关键词： adhesion hysteresis friction viscoelasticity frictional vibration dynamic monitoring

Kinetic Model of Fixed Bed reactor with Immobilized Microorganisms for removing low-Concentration SO_2

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Journal of Natural gas Chemistry 2007年第1期16卷 86-91页

作者： Bing Huang YanyanWang Shiling Zhang Yong ao Faculty of Environmental Science ＆ Engincering Kunming University of Science and Technology Kunming 650093 Yunnan China Faculty of Science Kunming University of Science and Technology Kunming 650093 Yunnan China

On the basis of the analysis of the process of treating low concentrations of sulfur dioxide （SO2） gas in a fixed bed reactor, a kinetic model is proposed for this process after taking into consideration the effects of internal diffusion, cell concentration, and production yield of microorganisms but ignoring the effect of external diffusion. The results obtained from the model simulation show that this model can indicate the influence of the process factors, Cin, η μmax, Cx, A, h, Kin, and Q, on the removal of SO2 and that the prediction of the results by this model is also satisfactory. This kinetic model can also provide some very important indications regarding the preparation of immobilized microorganisms, selection and domestication of proper species of microorganisms, as well as the design of bioreactors.

关键词： fixed bed reactor kinetic model immobilized microorganisms removal sulfur dioxide

Toward an understanding of dwell fatigue damage mechanism of bimodal Ti-6Al-4V alloys

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Journal of Materials Science & Technology 2022年第13期108卷 244-255页

作者： l.r.Zeng l.M.lei X.M.luo g.P.Zhang Shenyang National laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Mechanical Engineering Chengdu UniversityChengdu 610106China AECC Shanghai Commercial Aircraft Engine Manufacturing Co. Ltd.Shanghai 201306China

Dwell fatigue effect is a long-standing problem threatening the long-term service reliability for fan blades and fan disks of an aircraft *** understand the basic mechanism of dwell fatigue damage,pure fatigue and 60 s dwell fatigue properties of bimodal Ti-6Al-4V alloys with different volume fractions of the primaryα(α_(p))phase were examined *** results showed that both pure fatigue and dwell fatigue life decreased with increasing the volume fraction of theα_(p)phase and the dwell fatigue life was lower than the pure fatigue *** quasi-in-situ test results and the quantitative characterization of damage behaviors of the local microstructure units defined by theα_(p)-secondaryα(α_(s))combination reveal that theα_(s)phase close to theα_(p)phase with extensively slip activities was gradually damaged under dwell fatigue loading,while that under pure fatigue loading was undamaged,demonstrating that the dwell loading induced the damage of theα_(s)phase,and further reduced the fatigue life.A stress relaxation-based model is proposed to describe the physical mechanism on dwell fatigue damage of the bimodal Ti-6Al-4V alloy,*** elastic deformation of theα_(s)phase caused by the strain incompatibility would be gradually transformed into plastic deformation during the dwell stage,and thus promotes fatigue *** model provides new insights into the microscopic process of stress/strain transfer between the soft and hard microstructure units under dwell fatigue loading.

关键词： Dwell effect Fatigue damage Stress relaxation Volume fraction of primaryαphase Quasi-in-situ testing

Soft transmission of 3D video for low power and low complexity scenario

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Digital Communications and Networks 2023年第3期9卷 769-778页

作者： ao li Taihai Yang Wenxin Wu lei luo School of Communications and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China School of Computer Science and Technology East China Normal UniversityShanghai200062China School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu611731China

Thanks to the rapid development of naked-eye 3D and wireless communication technology,3D video related applications on mobile devices have attracted a lot of ***,the time-varying characteristics of the wireless channel is very challenging for conventional source-channel coding based transmission ***,the high complexity of source-channel coding based transmission scheme is undesired for low power mobile *** advanced transmission scheme named Softcast was proposed to achieve efficient transmission performance for 2D image/***,it cannot be directly applied to wireless 3D video transmission with high *** paper proposes a more efficient soft transmission scheme for 3D video with a graceful quality adaptation within a wide range of channel Signal-to-Noise ratio(SNr).The proposed method first extends the linear transform to 4 dimensions with additional view dimension to eliminate the view redundancy,and then metadata optimization and chunk interleaving are designed to further improve the transmission ***,a synthesis distortion based chunk discard strategy is developed to improve the overall 3D video quality under the condition of limited *** experimental results demonstrate that the proposed method significantly improves the 3D video transmission performance over the wireless channel for low power and low complexity scenarios.

关键词： Softcast low power 3D video Wireless

generalized degradation reliability model considering phase transition

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Journal of Systems Engineering and Electronics 2022年第3期33卷 748-758页

作者： ZHANg ao WANg Zhihua WU Qiong lIU Chengrui School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Institute of Spacecraft System Engineering China Academy of Space TechnologyBeijing 100094China Beijing Institute of Control Engineering Beijing 100094China

Aiming to evaluate the reliability of phase-transition degrading systems,a generalized stochastic degradation model with phase transition is constructed,and the corresponding analytical reliability function is formulated under the concept of the first hitting *** phase-varying stochastic property and the phase-varying nonlinearity are considered simultaneously in the proposed *** capture the phase-varying stochastic pro-perty,a Wiener process is adopted to model the non-monotonous degradation phase,while a gamma process is utilized to model the monotonous *** addition,the phase-varying non-linearity is captured by different transformed time scale *** facilitate the practical application of the proposed model,identification of phase model type and estimation of model parameters are discussed,and the initial guesses for parameters optimization are also *** on the constructed model,two simulation studies are carried out to verify the analytical reliability function and analyze the influence of model ***,a practical case study is conducted for illustration.

关键词： degradation phase transition reliability stochastic process nonlinearity

Subjective assessment for an advanced driver assistance system:a case study in China

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Journal of Intelligent and Connected Vehicles 2022年第2期5卷 112-122页

作者： Di ao Jialin li Department of Electromechanical Engineering Faculty of Science and TechnologyUniversity of MacaoMacao SARChina Department of Vehicle Engineering School of Automotive and Transportation EngineeringHefei University of TechnologyHefeiChina

Purpose–This study aims to propose a novel subjective assessment(SA)method for level 2 or level 21 advanced driver assistance system(ADAS)with a customized case study in ***/methodology/approach–The proposed SA method contains six dimensions,including perception,driveability and stability,riding comfort,human–machine interaction,driver workload and trustworthiness and exceptional operating case,*** each dimension subordinates several subsections,which describe the corresponding details under this ***–Based on the proposed SA,a case study in China is *** drivers with different driving experiences are invited to give their subjective ratings for each subsection according to a predefined rating *** rating results show that the ADAS from Tesla outperforms the upcoming electric vehicle in most ***/value–The proposed SA method is beneficial for the original equipment manufacturers developing related technologies in the future.

关键词： level 2 or 21 Advanced driver assistance system Subjective assessment method Six dimensions Case study

Development of an ANN-based building energy model for information-poor buildings using transfer learning

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Building Simulation 2021年第1期14卷 89-101页

作者： ao li Fu Xiao Cheng Fan Maomao Hu Department of Building Services Engineering The Hong Kong Polytechnic UniversityHong KongChina Department of Construction Management and real Estate College of Civil EngineeringShenzhen UniversityShenzhenChina Oxford e-research Centre Department of Engineering Science University of OxfordOxfordUK

Accurate building energy prediction is vital to develop optimal control strategies to enhance building energy efficiency and energy *** recent years,the data-driven approach based on machine learning algorithms has been widely adopted for building energy prediction due to the availability of massive data in building automation systems(BASs),which automatically collect and store real-time building operational *** new buildings and most existing buildings without installing advanced BASs,there is a lack of sufficient data to train data-driven predictive *** learning is a promising method to develop accurate and reliable data-driven building energy prediction models with limited training data by taking advantage of the rich data/knowledge obtained from other *** studies focused on the influences of source building datasets,pre-training data volume,and training data volume on the performance of the transfer learning *** present study aims to develop a transfer learning-based ANN model for one-hour ahead building energy prediction to fill this research *** 400 non-residential buildings’data from the open-source Building genome Project are used to test the proposed *** analysis demonstrates that transfer learning can effectively improve the accuracy of BPNN-based building energy models for information-poor buildings with very limited training *** most influential building features which influence the effectiveness of transfer learning are found to be building usage and *** research outcomes can provide guidance for implementation of transfer learning,especially in selecting appropriate source buildings and datasets for developing accurate building energy prediction models.

关键词： building energy prediction data-driven approach transfer learning neural network information poor buildings

relation reconstructive Binarization of word embeddings

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Frontiers of Computer Science 2022年第2期16卷 47-54页

作者： Feiyang PAN Shuokai lI Xiang ao Qing HE Key lab of Intelligent Information Processing of Chinese Academy of Sciences(CAS) Institute of Computing TechnologyCASBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Word-embedding acts as one of the backbones of modern natural language processing(NlP).recently,with the need for deploying NlP models to low-resource devices,there has been a surge of interest to compress word embeddings into hash codes or binary vectors so as to save the storage and memory ***,existing work learns to encode an embedding into a compressed representation from which the original embedding can be *** these methods aim to preserve most information of every individual word,they often fail to retain the relation between words,thus can yield large loss on certain *** this end,this paper presents relation reconstructive Binarization(r2B)to transform word embeddings into binary codes that can preserve the relation between *** its heart,r2B trains an auto-encoder to generate binary codes that allow reconstructing the wordby-word relations in the original embedding *** showed that our method achieved significant improvements over previous methods on a number of tasks along with a space-saving of up to 98.4%.Specifically,our method reached even better results on word similarity evaluation than the uncompressed pre-trained embeddings,and was significantly better than previous compression methods that do not consider word relations.

关键词： embedding compression variational auto-encoder binary word embedding

Prediction on CO2 uptake of recycled aggregate concrete

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Frontiers of Structural and Civil Engineering 2020年第3期14卷 746-759页

作者： Kaiwen HUANg ao lI Bing XIA Tao DINg Department of Structural Engineeving College of Civil EngineeringTongji UniversityShanghai 200092China Shanghai International Airport Company limited Shanghai 200152China

Carbonation of concrete is a process which absorbs carbon dioxide (CO2). recycled aggregate concrete(rAC) may own greater potential in CO2 uptake due to the faster carbonation rate than natural aggregate concrete (NAC).A quantitative model was employed to predict the CO2 uptake of rAC in this study. The carbonation of rAC and thespecific surface area of recycled coarse aggregates (rCAs) were tested to verify accuracy of the quantitative model. Basedon the verified model, results show that the CO2 uptake capacity increases with the increase of rCA replacementpercentage. The CO2 uptake amount of 1 m^3 C30 rAC within 50 years is 10.6, 13.8, 17.2, and 22.4 kg when the rCAreplacement percentage is 30%, 50%, 70%, and 100%, respectively. The CO2 uptake by rCAs is remarkable and reaches35.8%- 64.3% of the total CO2 uptake by rAC when the rCA storage time being 30 days. Considering the fact that theamount of old hardened cement paste in rCAs is limited, there is an upper limit for the CO2 uptake of rCAs.

关键词： rAC CO2 uptake carbonation specific surface area rCA

Crystal structure of E. coli arginyl-trNA synthetase and ligand binding studies revealed key residues in arginine recognition

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Protein & Cell 2014年第2期5卷 151-159页

作者： Kelei Bi Yueting Zheng Feng g"ao Jianshu Dong Jiangyun Wang Yi Wang Weimin gong laboratory of Non-coding rNA Institute of Biophysics Chinese Academy of Sciences

The arginyl-trNA synthetase(ArgrS) catalyzes the esterification reaction between l-arginine and its cognate trNAArg. Previously reported structures of ArgrS shed considerable light on the trNA recognition mechanism, while the aspect of amino acid binding in ArgrS remains largely unexplored. Here we report the first crystal structure of E. coli ArgrS(eArgrS) complexed with l-arginine, and a series of mutational studies using isothermal titration calorimetry(ITC). Combined with previously reported work on ArgrS, our results elucidated the structural and functional roles of a series of important residues in the active site, which furthered our understanding of this unique enzyme.

关键词： arginyl-trNA synthetase amino acyl-trNA synthetase isothermal titration calorimetry site-directed mutation X-ray crystal structure E. coli