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A gauge theory for two-band model of Chern insulators and induced topological defects

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Communications in Theoretical Physics 2022年第1期74卷 124-133页

作者： Zhi-Wen chang wei-chang hao Xin Liu Institute of Theoretical Physics Faculty of SciencesBeijing University of TechnologyBeijing 100124China School of Physics Beihang UniversityBeijing 100191China

In this paper a gauge theory is proposed for the two-band model of Chern *** on the so-calle't Hooft monopole model,a U(1)Maxwell electromagnetic sub-field is constructed from an SU(2)gauge field,from which arise two types of topological defects,monopoles and e2 *** focus on the topological number in the Hall conductance σ_(xy)=e^(2)/hC,where C is the Chern *** is discovered that in the monopole case C is indeterminate,while in the meron case C takes different values,due to a varying on-site energy *** a typical example,we apply this method to the square lattice and compute the winding numbers(topological charges)of the defects;the C-evaluations we obtain reproduce the results of the usual ***,based on the gauge theory we propose a new model to obtain the high Chern numbers|C|=2,4.

关键词： Chern insulator Chern number monopole meron

Effect of tubastatin A on NLRP3 inflammasome activation in macrophages under hypoxia/ reoxygenation conditions

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World Journal of Emergency Medicine 2024年第4期15卷 289-296页

作者： hao Li chang Liu Ying Cui Panpan chang wei Chong Department of Emergency Medicine the First Hospital of China Medical UniversityShenyang 110001China Trauma Medicine Center Peking University People's HospitalBeijing 100871China Key Laboratory of Trauma and Neural Regeneration Peking UniversityBeijing 100871China National Center for Trauma Medicine of China Beijing 100871China

BACKGROUND:There are currently no effective drugs to mitigate the ischemia/reperfusion injury caused by fluid resuscitation after hemorrhagic shock(HS).The aim of this study was to explore the potential of the histone deacetylase 6(HDAC6)-specific inhibitor tubastatin A(TubA)to suppress nucleotide-binding oligomerization domain-like receptor protein 3(NLRP3)inflammasome activation in macrophages under hypoxia/reoxygenation(H/R)***:The viability of RAW264.7 cells subjected to H/R after treatment with different concentrations of TubA was assessed using a cell-counting kit-8(CCK8)***,2.5μmol/L TubA was used with RAW264.7 cells under H/R ***264.7 cells were divided into three groups,namely the control,H/R,and TubA *** levels of reactive oxygen species(ROS)in the cells were detected using fluorescence *** protein expression of HDAC6,heat shock protein 90(Hsp90),inducible nitric oxide synthase(iNOS),NLRP3,gasdermin-D(GSDMD),Caspase-1,GSDMD-N,and Caspase-1 p20 was detected by western *** levels of interleukin-1β(IL-1β)and IL-18 in the supernatants were detected using enzyme-linked immunosorbent assay(ELISA).RESULTS:HDAC6,Hsp90,and iNOS expression levels were significantly higher(P<0.01)in the H/R group than in the control group,but lower in the TubA group than in the H/R group(P<0.05).When comparing the H/R group to the control group,ROS levels were significantly higher(P<0.01),but significantly reduced in the TubA group(P<0.05).The H/R group had higher NLRP3,GSDMD,Caspase-1,GSDMD-N,and Caspase-1 p20 expression levels than the control group(P<0.05),however,the TubA group had significantly lower expression levels than the H/R group(P<0.05).IL-1βand IL-18 levels in the supernatants were significantly higher in the H/R group compared to the control group(P<0.01),but significantly lower in the TubA group compared to the H/R group(P<0.01).CONCLUSION:TubA inhibited the expression of HDAC6,Hsp90,and iNOS in macrophages

关键词： Hemorrhagic shock Hypoxia/reoxygenation Macrophage NLRP3 Tubastatin A

MLDA:a multi-level k-degree anonymity scheme on directed social network graphs

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Frontiers of Computer Science 2024年第2期18卷 199-215页

作者： Yuanjing hao Long LI Liang chang Tianlong GU Guangxi Key Laboratory of Trusted Software Guilin University of Electronic TechnologyGuilin 541004China Engineering Research Center of Trustworthy AI(Ministry of Education) Jinan UniversityGuangzhou 510632China

With the emergence of network-centric data,social network graph publishing is conducive to data analysts to mine the value of social networks,analyze the social behavior of individuals or groups,implement personalized recommendations,and so ***,published social network graphs are often subject to re-identification attacks from adversaries,which results in the leakage of users’***-anonymity technology is widely used in the field of graph publishing,which is quite effective to resist re-identification ***,the current researches still exist some issues to be solved:the protection of directed graphs is less concerned than that of undirected graphs;the protection of graph structure is often ignored while achieving the protection of nodes’identities;the same protection is performed for different users,which doesn’t meet the different privacy requirements of ***,to address the above issues,a multi-level-degree anonymity(MLDA)scheme on directed social network graphs is proposed in this ***,node sets with different importance are divided by the firefly algorithm and constrained connectedness upper approximation,and they are performed different-degree anonymity protection to meet the different privacy requirements of ***,a new graph anonymity method is proposed,which achieves the addition and removal of edges with the help of fake *** addition,to improve the utility of the anonymized graph,a new edge cost criterion is proposed,which is used to select the most appropriate edge to be ***,to protect the community structure of the original graph as much as possible,fake nodes contained in a same community are merged prior to fake nodes contained in different *** results on real datasets show that the newly proposed MLDA scheme is effective to balance the privacy and utility of the anonymized graph.

关键词： directed social network graph graph publishing k-degree anonymity community structure graph utility

Optimization of Hydrocracking Process for Enhanced BTX Production from Coal Tar-Derived Hydrorefined Products

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 139-151页

作者： Wu hao wei Hongyuan School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China

Hydroconversion of coal tar to produce aromatic hydrocarbons(BTX)represents a crucial strategy for the highvalue hierarchical utilization of *** study focused on the hydrocracking of hydrorefined products derived from coal tar to enhance the production of benzene,toluene,and xylene(BTX).Various reaction conditions,including reaction temperature,hydrogen pressure,space velocity,and hydrogen-to-oil volume ratio,were systematically explored to optimize BTX yields while also considering the process’s economic *** results indicate that increasing the reaction temperature from 360℃ to 390℃ significantly favors the production of BTX,with yields increasing from 21.42%to 41.14%.Similarly,an increase in hydrogen pressure from 4 MPa to 6 MPa boosts BTX production,with yields rising from 36.31%to 41.14%.Reducing the space velocity from 2 h^(-1) to 0.5 h^(-1) also favors the BTX production process,with yields increasing from 37.96%to 45.13%.Furthermore,raising the hydrogen-to-oil volume ratio from 750 to 1500 improves BTX yields from 41.61%to 45.44%.Through economic analysis,the optimal conditions for BTX production were identified as a reaction temperature of 390℃,hydrogen pressure of 5-6 MPa,space velocity of 1 h^(-1),and hydrogen-to-oil volume ratio of 1000,achieving a BTX yield of 43.73%.This investigation highlights the importance of a holistic evaluation of hydrocracking conditions to optimize BTX ***,the findings offer valuable insights for the design and operation of industrial hydrocracking processes aimed at efficiently converting coal tar-derived hydrorefined feedstock into BTX.

关键词： coal tar hydrocracking BTX process optimization economic assessment

Customer Joining Behavior and Regulation Strategy in Visible Multi-Server Queues with Synchronous Vacations of Partial Servers

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Journal of Systems Science & Complexity 2024年第3期37卷 1209-1232页

作者： SUN wei WANG hao XIE Xumeng LI Shiyong School of Economics and Management Yanshan UniversityQinhuangdao 066004China

This paper studies customer joining behavior and system regulation strategy in nonexhaustive visible M/M/m queues with synchronous vacations of a part of the *** this part of the servers are idle,they take multiple vacations simultaneously(vacation period).Until there are customers waiting in the queue,they are reactivated and all servers are busy or idle(busy period).The authors call this part of the servers as“partial servers”.In view of the fully visible queue and the almost visible queue,the authors obtain customers’equilibrium joining threshold strategies and their socially optimal joining threshold strategies,respectively,and observe that customer joining behavior in equilibrium generally makes the system overcrowded,which makes the equilibrium social welfare lower than the optimal social *** regulation,interestingly,for optimizing social welfare,the system manager hopes not only customers arriving in vacation period pay attention to the number of partial servers,but also customers arriving in busy period should care about it rather than ***,arranging more servers for vacation does not necessarily lead to the decrease of social welfare on condition that the number of partial servers is close to *** for the information advantage of the fully visible case,it is not obvious for increasing social welfare and even unfavorable to servers’profit unless the number of partial servers is big ***,given the different composition of social welfare,there exists the optimal number of partial servers and the optimal arrival rate of customers for maximizing social welfare.

关键词： Customer behavior non-exhaustive service partial servers regulation strategy synchronous vacations visible queue

Asymmetric time-varying integral barrier Lyapunov function based adaptive optimal control for nonlinear systems with dynamic state constraints

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Frontiers of Information Technology & Electronic Engineering 2024年第6期25卷 887-902页

作者： Yan wei Mingshuang hao Xinyi YU Linlin OU College of Information Engineering Zhejiang University of TechnologyHangzhou 310023China

This paper investigates the issue of adaptive optimal tracking control for nonlinear systems with dynamic state *** asymmetric time-varying integral barrier Lyapunov function(ATIBLF)based integral reinforcement learning(IRL)control algorithm with an actor–critic structure is first *** ATIBLF items are appropriately arranged in every step of the optimized backstepping control design to ensure that the dynamic full-state constraints are never ***,optimal virtual/actual control in every backstepping subsystem is decomposed with ATIBLF items and also with an adaptive optimized ***,neural networks are used to approximate the gradient value *** to the Lyapunov stability theorem,the boundedness of all signals of the closed-loop system is proved,and the proposed control scheme ensures that the system states are within predefined compact ***,the effectiveness of the proposed control approach is validated by simulations.

关键词： State constraints Asymmetric time-varying integral barrier Lyapunov function(ATIBLF) Adaptive optimal control Nonlinear systems

Advancements in machine learning for material design and process optimization in the field of additive manufacturing

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China Foundry 2024年第2期21卷 101-115页

作者： hao-ran Zhou hao Yang Huai-qian Li Ying-chun Ma Sen Yu Jian shi Jing-chang Cheng Peng Gao Bo Yu Zhi-quan Miao Yan-peng wei National Key Laboratory of Advanced Casting Technologies Shenyang Research Institute of Foundry Co.Ltd.CAMShenyang 110022China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Space Physics Beijing 100076China School of Materials Science and Engineering Nanyang Technological University639798Singapore

Additive manufacturing technology is highly regarded due to its advantages,such as high precision and the ability to address complex geometric ***,the development of additive manufacturing process is constrained by issues like unclear fundamental principles,complex experimental cycles,and high *** learning,as a novel artificial intelligence technology,has the potential to deeply engage in the development of additive manufacturing process,assisting engineers in learning and developing new *** paper provides a comprehensive overview of the research and applications of machine learning in the field of additive manufacturing,particularly in model design and process ***,it introduces the background and significance of machine learning-assisted design in additive manufacturing *** then further delves into the application of machine learning in additive manufacturing,focusing on model design and process ***,it concludes by summarizing and forecasting the development trends of machine learning technology in the field of additive manufacturing.

关键词： additive manufacturing machine learning material design process optimization intersection of disciplines embedded machine learning

A new strain-based pentagonal membrane finite element for solid mechanics problems

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Theoretical & Applied Mechanics Letters 2024年第3期14卷 211-216页

作者： wei hao Koh Logah Perumal CheeKuang Kok Faculty of Engineering and Technology Multimedia UniversityMelaka 75450Malaysia

Polygonal finite elements remain an attractive option in finite element analysis due to their flexibility in modelingarbitrary shapes compared to *** this study,a pentagonal membrane element was developed with thestrain approach for the first *** element possesses invariance,and the equilibrium constraint was appliedto the assumed strain field using corrective *** by the advancing front technique,a pentagonalmesh was generated,and the mesh quality was enhanced with Laplacian *** performance of thedeveloped pentagonal element was assessed in a few numerical tests,and the results revealed its suitability inmodeling the bending of ***,the numerical results are enhanced when pentagonal elements are usedin mesh transitions along boundaries to smoothen curved edges and capture distributed loads.

关键词： Strain-based pentagonal element Corrective coefficients EquilibriumLaplacian smoothing Pentagonal mesh Mesh transition

A comparative investigation on wear behaviors of physical and chemical vapor deposited bronze coatings for hydraulic piston pump

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Chinese Journal of Aeronautics 2024年第3期37卷 391-403页

作者： wei hao Andrews LARBI Hongkang DONG Dongyun WANG Shenghu LI Zhejiang Provincial Key Laboratory of Urban Rail Transit Intelligent Operation and Maintenance Technology and Equipment Zhejiang Normal UniversityJinhua 321004China College of Engineering Zhejiang Normal UniversityJinhua 321004China Hangzhou Lilong Hydraulic Co. LtdHangzhou 311200China

The cylinder block/valve plate interface is one of the most critical frictional interfaces of the swashplate-type axial piston ***,the poor lubrication interface caused rapid wear and high friction loss in an elastohydrodynamic lubrication system,decreasing the pump *** resistant bronze coatings were fabricated on 38CrMoAl substrate by Physical Vapor Deposition(PVD)and Chemical Vapor Deposition(CVD),***-on-disc wear tests were performed to comparatively investigate the wear behaviors of the coatings and bulk ductile iron *** can be found that the PVD-bronze coating exhibited better wear resistance than the other two *** enhanced wear resistance was attributed to the unique composite microstructure and desired mechanical strength,which could resist to mechanical shear and spallation,decreasing friction *** appropriate hardness of(1.33±0.07)GPa could be beneficial for enhancing its wear *** PVD-bronze coating possessed a much lower and stable coefficient of friction(about 0.1)and wear rate(about 6000μm3.N-1.m-1)under the loading forces of about 100 N after 20 *** wear mechanism was the abrasive wear.

关键词： Aircraft hydraulic pump Bronze Coatings Wear resistance Mechanisms