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Effect of multilayer graphene/nano-Fe2O3 composite additions on dry sliding wear behavior of titanium matrix composites

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Journal of Iron and Steel Research International 2020年第9期27卷 1117-1126页

作者： Huang Xie Yun-xue jin Mu-ye Niu ji-heng wang School of Material Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003JiangsuChina National Demonstration Center for Experimental Materials Science and Engineering Education(jiangsu University of Science and Technology) Zhenjiang 212003JiangsuChina

The wear tests of titanium matrix composites(TMCs)at the loads of 50,100,120,and 150 N were carried out with an MMW-1 vertical universal friction and wear tester to study the addition of multilayer graphene(MLG)/nano-Fe2O3 composites(0,0.1,0.2,0.3,0.4,and 0.5 g)on the dry sliding wear behavior of *** presented a marked variation in wear loss as a function of the amount of MLG/Fe2O3 addition,and a significant decrease in the friction coefficient was obtained,reducing this parameter up to 50%.With the rise and fall of wear loss,TMCs underwent a transition from severe wear to mild *** phenomena were attributed to the existence of a protective lubricating film,which prevented the surface from coming in direct contact,and the lubricating film was 15-20μm thick and made up of MLG/Fe2O3(1:2)*** structure was speculated to be similar to a rolling wood.

关键词： Titanium matrix composite Graphene Nanomaterial Lubricating film Wear behavior

Correlation between age of onset and gastrointestinal stenosis in hospitalized patients with Crohn's disease

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World Journal of Clinical Cases 2020年第13期8卷 2769-2777页

作者： Shan-Bing Yang Shu-Wen Du ji-heng wang Department of Gastroenterology the Seventh Medical CenterChinese People’s Liberation Army General HospitalBeijing 100700China

BACKGROUND Patients affected by Crohn's disease(CD)are more likely to develop gastrointestinal stenosis and often undergo surgery during the duration of *** To identify the risk factors for gastrointestinal stenosis in hospitalized CD patients in *** The clinical data of CD patients hospitalized at the Seventh Medical Center,Chinese People's Liberation Army General Hospital from January 2010 to December 2018 were *** with gastrointestinal stenosis were compared to those without gastrointestinal stenosis for clinical *** risk factors for gastrointestinal stenosis were identified using univariate and multivariable logistic regression *** treatments for patients with gastrointestinal stenosis were analyzed,and the characteristics of different treatment methods were *** The incidence of gastrointestinal stenosis was 59.02%in the 122 hospitalized CD *** of onset of more than 40 years(odds ratio[OR]=3.072,95%confidence interval[CI]:1.298-7.272,P=0.009)and duration of disease of more than 5 years(OR=2.101,95%CI:1.002-4.406,P=0.048)were associated with the occurrence of gastrointestinal ***(20.83%)patients did not undergo surgery and received internal medicine and nutrition *** treatments were performed in 72.22%(52)of *** rate of postoperative complications was 15.38%(8 cases),and during a median follow-up period of 46 mo,11.54%(6 cases)underwent reoperation.A total of 29.17%(21 cases)were treated with endoscopic therapy,and during a median follow-up period of 32 mo,76.19%(16 cases)had no surgical event,23.81%(5 cases)failed to avoid surgical treatments,and no serious postoperative complications occurred after endoscopic *** Age of onset of more than 40 years and duration of disease of more than 5 years may be strongly correlated with a higher risk of gastrointestinal stenosis in hospitalized CD *** therapy for gastrointestinal stenosis

关键词： Crohn's disease Gastrointestinal stenosis Age of onset Duration of disease Endoscopy Surgery

Identifying Three New AGNs among Fermi Unidentified Gigaelectronvolt Sources

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Research in Astronomy and Astrophysics 2024年第7期24卷 257-267页

作者： Shun-Hao ji Zhong-Xiang wang Qiang-Meng Huang Ruo-heng Yang Department of Astronomy School of Physics and AstronomyYunnan UniversityKunming 650091China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China

We report our identification of three gigaelectronvoltγ-ray sources,4FGL J0502.6+0036,4FGL J1055.9+6507,and 4FGL J1708.2+5519,as Active Galactic Nuclei(AGNs).They are listed in the latest Fermi-Large Area Telescope source catalog as unidentified *** find that the sources all showedγ-ray flux variations in recent *** different survey catalogs,we are able to find a radio source within the error circle of each source's *** analysis of optical sources in the fields allows us to determine the optical counterparts,which showed similar variation patterns to those seen inγ-*** optical counterparts have reported redshifts of 0.6,1.5,and 2.3,respectively,estimated from photometric *** addition,we also obtain an X-ray spectrum of 4FGL J0502.6+0036 and a flux upper limit on the X-ray emission of 4FGL J1055.9+6507 by analyzing the archival *** broadband spectral energy distributions of the three sources from radio toγ-rays are *** mainly theγ-ray properties of the three sources with those of different sub-classes of AGNs,we tentatively identify them as *** optical spectroscopy is highly warranted for obtaining their spectral features and thus verifying the identification.

关键词： gamma-rays galaxies-(galaxies)BL Lacertae objects general-(galaxies)quasars general

维普期刊数据库

Value iteration algorithm for continuous-time linear quadratic stochastic optimal control problems

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Science China(Information Sciences) 2024年第2期67卷 170-180页

作者： Guangchen wang heng ZHANG School of Control Science and Engineering Shandong University

In this study, we investigate a continuous-time infinite-horizon linear quadratic stochastic optimal control problem with multiplicative noise in control and state variables. Using the techniques of stochastic stability, exact observability, and stochastic approximation, a value iteration algorithm is developed to solve the corresponding generalized algebraic Riccati equation. Unlike the existing policy iteration algorithm, this algorithm does not rely on an initial stabilizing control. Further, this algorithm can also be used to compute policy evaluation steps that arise in the policy iteration algorithm. Herein, a simulation example is provided to validate the obtained results.

关键词： stochastic systems optimal control linear quadratic stochastic problem generalized algebraic Riccati equation value iteration algorithm

An attention graph stacked autoencoder for anomaly detection of electro-mechanical actuator using spatio-temporal multivariate signals

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Chinese Journal of Aeronautics 2024年第9期37卷 506-520页

作者： jianyu wang heng ZHANG Qiang MIAO College of Electrical Engineering Sichuan UniversityChengdu 610065China

Health monitoring of electro-mechanical actuator(EMA)is critical to ensure the security of *** is difficult or even impossible to collect enough labeled failure or degradation data from actual *** autoencoder based on reconstruction loss is a popular model that can carry out anomaly detection with only consideration of normal training data,while it fails to capture spatio-temporal information from multivariate time series signals of multiple monitoring *** mine the spatio-temporal information from multivariate time series signals,this paper proposes an attention graph stacked autoencoder for EMA anomaly ***,attention graph con-volution is introduced into autoencoder to convolve temporal information from neighbor features to current features based on different weight ***,stacked autoencoder is applied to mine spatial information from those new aggregated temporal ***,based on the bench-mark reconstruction loss of normal training data,different health thresholds calculated by several statistic indicators can carry out anomaly detection for new testing *** comparison with tra-ditional stacked autoencoder,the proposed model could obtain higher fault detection rate and lower false alarm rate in EMA anomaly detection experiment.

关键词： Anomaly detection Spatio-temporal informa-tion Multivariate time series signals Attention graph convolution Stacked autoencoder

Light People: Professor Fanglin Bao and his cover story

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Light(Science & Applications) 2024年第6期13卷 1015-1020页

作者： ji wang School of Science Westlake UniversityHangzhouZhejiangPR China

Qu Yuan,a renowned ancient Chinese poet,once pondered in his work Heavenly Inquiry:“If the sun’s light is absent,from where does the radiance of the Hero Flower emanate?”The ability to see clearly in the darkest of nights has long been a sought-after magical power by *** holds not only immense technological significance for computer vision and remote sensing but also profound implications for transcending the dichotomy between day and night in our daily *** Fanglin Bao from Westlake University has made significant breakthroughs in this field,bringing us closer to a world where we can transform night into *** groundbreaking research on Heat-Assisted Detection and Ranging(HADAR)and night vision was featured as the cover story in Nature on July 26,2023.

关键词： bringing breakthrough holds

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Science China Mathematics 2024年第2期67卷 405-430页

作者： Junzhuo Gao Lei wang heng Lian School of Statistics and Data Science&LPMC Nankai UniversityTianjin 300071China Department of Mathematics City University of Hong KongHong KongChina

In this paper, we consider the unified optimal subsampling estimation and inference on the lowdimensional parameter of main interest in the presence of the nuisance parameter for low/high-dimensionalgeneralized linear models (GLMs) with massive data. We first present a general subsampling decorrelated scorefunction to reduce the influence of the less accurate nuisance parameter estimation with the slow convergencerate. The consistency and asymptotic normality of the resultant subsample estimator from a general decorrelatedscore subsampling algorithm are established, and two optimal subsampling probabilities are derived under theA- and L-optimality criteria to downsize the data volume and reduce the computational burden. The proposedoptimal subsampling probabilities provably improve the asymptotic efficiency of the subsampling schemes in thelow-dimensional GLMs and perform better than the uniform subsampling scheme in the high-dimensional GLMs.A two-step algorithm is further proposed to implement, and the asymptotic properties of the correspondingestimators are also given. Simulations show satisfactory performance of the proposed estimators, and twoapplications to census income and Fashion-MNIST datasets also demonstrate its practical applicability.

关键词： A-optimality decorrelated score subsampling high-dimensional inference L-optimality massive data

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Resilience-oriented Transmission Expansion Planning with Optimal Transmission Switching Under Typhoon Weather

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 129-138页

作者： Yang Yuan heng Zhang Haozhong Cheng Zheng wang Key Laboratory of Control of Power Transmission and Conversion Ministry of EducationElectrical Engineering DepartmentShanghai Jiao Tong UniversityShanghaiChina State Grid East China Branch ShanghaiChina

This paper presents resilience-oriented transmission expansion planning(RTEP)with optimal transmission switching(OTS)model under typhoon *** proposed model carefully considers the uncertainty of component vulnerability by constructing a typhoon-related box uncertainty set where component failure rate varies within a range closely related with typhoon ***,a min-max-min model is developed to enhance transmission network resilience,where the upper level minimizes transmission lines investment,the middle level searches for the probability distribution of failure status leading to max worst-case expected load-shedding(WCEL)under typhoon,and the lower level optimizes WCEL by economic dispatch(ED)and OTS.A nested decomposition algorithm based on benders decomposition is developed to solve the *** studies of modified IEEE 30-bus and 261-bus system of a Chinese region illustrate that:a)the proposed RTEP method can enhance resilience of transmission network with less investment than widely used RTEP method based on attacker and defender(DAD)model,b)the influence of OTS on RTEP is closely related with contingency severity and system scale and c)the RTEP model can be efficiently solved even in a large-scale system.

关键词： Decomposition algorithm optimal transmission switching resilience transmission expansion planning uncertainty vulnerability

Immunomodulation of Proton-activated G Protein-coupled Receptors in Inflammation

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Current Medical Science 2024年第3期44卷 475-484页

作者： Min-shan LI Xiang-hong wang heng wang Department of Otolaryngology-Head and Neck Surgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Institute of Allergy and Clinical Immunology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Hubei Clinical Research Center for Nasal Inflammatory Diseases Wuhan430030China

Proton-activated G protein-coupled receptors(GPCRs),initially discovered by Ludwig in 2003,are widely distributed in various *** receptors have been found to modulate the immune system in several inflammatory diseases,including inflammatory bowel disease,atopic dermatitis,and ***-activated GPCRs belong to the G protein-coupled receptor family and can detect alternations in extracellular *** detection triggers downstream signaling pathways within the cells,ultimately influencing the function of immune *** this review,we specifically focused on investigating the immune response of proton-activated GPCRs under inflammatory conditions.

关键词： proton-activated G protein-coupled receptors inflammation immunomodulation disease