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Frontiers of Structural and Civil Engineering 2024年第4期18卷 568-586页

作者： Fu-wei WU Yuan-qi LI department of Structural Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

The derivation and validation of analytical equations for predicting the tensile initial stiffness of threadfixed one-side bolts(TOBs),connected to enclosed rectangular hollow section(RHS)columns,is presented in this *** unknown stiffness components are considered:the TOBs connection and the enclosed RHS ***,the trapezoidal thread of TOB,as an equivalent cantilevered beam subjected to uniformly distributed loads,is analyzed to determine the associated *** on the findings,the thread-shank serial-parallel stiffness model of TOB connection is *** analysis of the tensile stiffness of the enclosed RHS face due to two bolt forces,the four sidewalls are treated as rotation constraints,thus reducing the problem to a two-dimensional plate *** to the load superposition method,the deflection of the face plate is resolved into three components under various boundary and load *** to the plate deflection theory of Timoshenko,the analytical solutions for the three deflections are derived in terms of the variables of bolt spacing,RHS thickness,height to width ratio,***,the validity of the above stiffness equations is verified by a series of finite element(FE)models of T-stub *** proposed component stiffness equations are an effective supplement to the component-based method.

关键词： initial stiffness component based method thread-fixed one-side bolt rectangular hollow sections analytical equation

Comprehensive Evaluation Method for Traffic Flow Data Quality Based on Grey Correlation Analysis and Particle Swarm Optimization

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 106-128页

作者： wei Ba Baojun Chen qi Li School of Automation and Electrical Engineering Dalian Jiaotong UniversityDalian116028China Faculty of Electronic Information and Electrical Engineering Dalian University of TechnologyDalian116023China

Nowadays,data are more and more used for intelligent modeling and prediction,and the comprehensive evaluation of data quality is getting more and more attention as a necessary means to measure whether the data are usable or ***,the comprehensive evaluation method of data quality mostly contains the subjective factors of the evaluator,so how to comprehensively and objectively evaluate the data has become a bottleneck that needs to be solved in the research of comprehensive evaluation *** order to evaluate the data more comprehensively,objectively and differentially,a novel comprehensive evaluation method based on particle swarm optimization(PSO)and grey correlation analysis(GCA)is presented in this *** first,an improved GCA evaluation model based on the technique for order preference by similarity to an ideal solution(TOPSIS)is ***,an objective function model of maximum difference of the comprehensive evaluation values is built,and the PSO algorithm is used to optimize the weights of the improved GCA evaluation model based on the objective function ***,the performance of the proposed method is investigated through parameter analysis.A performance comparison of traffic flow data is carried out,and the simulation results show that the maximum average difference between the evaluation results and its mean value(MDR)of the proposed comprehensive evaluation method is 33.24%higher than that of TOPSIS-GCA,and 6.86%higher than that of *** proposed method has better differentiation than other methods,which means that it objectively and comprehensively evaluates the data from both the relevance and differentiation of the data,and the results more effectively reflect the differences in data quality,which will provide more effective data support for intelligent modeling,prediction and other applications.

关键词： Data quality comprehensive evaluation particle swarm optimization grey correlation analysis traffic flow data

Long-time Asymptotics for the Reverse Space-time Nonlocal Hirota Equation with decaying Initial Value Problem:without Solitons

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 708-727页

作者： wei-qi PENG Yong CHEN School of Mathematical Sciences East China Normal UniversityShanghai 200241China College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

In this work,we mainly consider the Cauchy problem for the reverse space-time nonlocal Hirota equation with the initial data rapidly decaying in the solitonless *** from the Lax pair,we first construct the basis Riemann-Hilbert problem for the reverse space-time nonlocal Hirota ***,using the approach of deift-Zhou nonlinear steepest descent,the explicit long-time asymptotics for the reverse space-time nonlocal Hirota is *** the reverse space-time nonlocal Hirota equation,since the symmetries of its scattering matrix are different with the local Hirota equation,the v(λ_(i))(i=0,1)would like to be imaginary,which results in theδ_(λi)^(0)contains an increasing t(±Imv(λ_(i)))/2,and then the asymptotic behavior for nonlocal Hirota equation becomes differently.

关键词： Riemann-Hilbert problem reverse space-time nonlocal Hirota equation long-time asymptotics nonlinear steepest descent method

Effect of alumina occurrence form on metallurgical properties of hematite and magnetite pellets

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Journal of Iron and Steel Research International 2024年第4期31卷 797-809页

作者： Jian Pan Chen-mei Tang Cong-cong Yang de-qing Zhu Zheng-qi Guo wei-qun Huang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Exploration and development of Geology and Mineral Resources Co. Ltd.Nanchang 330030JiangxiChina

The effect of alumina occurrence form on the metallurgical properties of both hematite and magnetite pellets was investigated at the same Al_(2)O level of 2 wt.%,including reduction index(RI),low-temperature reduction disintegration index(RDI),reduction swelling index(RSI),and high-temperature softening-dripping *** mineralogy of fired pellets was also studied to reveal the influence of alumina occurrence form on the phase composition and *** the results,the alumina occurrence form presents tremendous impacts on the metallurgical perfor-mance of both magnetite and hematite *** of all alumina occurrence forms contributes to inferior reducibility of pellets,especially in the case of gibbsite for magnetite pellets with a RI of 58.4%and kaolinite for hematite pellets with a RI of 56.8%.However,addition of all alumina occurrence forms improves the RDI of magnetite pellets,while there is no significant difference among various alumina occurrence *** contrast,alumina occurrence forms have little influence on the RDI of hematite *** presence of free alumina,gibbsite,and kaolinite tends to improve the RSI of hematite and magnetite pellets,whereas hercynite gives the opposite trend with a RSI of 25.6%.For softening-dripping performance of magnetite pellets,all alumina occurrence forms contribute to narrower softening-melting ***,alumina,gibbsite,and kaolinite give narrower softening-dripping interval,at 229,217,and 88℃,respectively,whereas addition of hercynite results in the largest melting range at 276℃ due to its high melting *** hematite pellets,free alumina,gibbsite,and hercynite tend to enlarge melting range,whereas kaolinite contributes to lower dripping temperature of 1148℃ and narrow softening-dripping interval of 88℃ due to the formation of a greater amount of slag phase at high temperatures.

关键词： Oxidized pellet Magnetite Hematite Alumina occurrence form Metallurgical performance Blast furnace

Intelligent Reflecting Surface Assisted Transmission Optimization Strategies in Wireless Networks

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China Communications 2024年第4期21卷 120-135页

作者： He Xinxin qi Xuan Meng wei Liu wei Yin Changchuan School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

Wireless Power Transfer(WPT)technology can provide real-time power for many terminal devices in Internet of Things(IoT)through millimeterWave(mmWave)to support applications with large capacity and low *** the intelligent reflecting surface(IRS)can be adopted to create effective virtual links to address the mmWave blockage problem,the conventional solutions only adopt IRS in the downlink from the Base Station(BS)to the users to enhance the received signal *** practice,the reflection of IRS is also applicable to the uplink to improve the spectral *** is a challenging to jointly optimize IRS beamforming and system resource allocation for wireless energy acquisition and information *** this paper,we first design a Low-Energy Adaptive Clustering Hierarchy(LEACH)clustering protocol for clustering and data ***,the problem of maximizing the minimum system spectral efficiency is constructed by jointly optimizing the transmit power of sensor devices,the uplink and downlink transmission times,the active beamforming at the BS,and the IRS dynamic *** solve this non-convex optimization problem,we propose an alternating optimization(AO)-based joint solution *** results show that the use of IRS dynamic beamforming can significantly improve the spectral efficiency of the system,and ensure the reliability of equipment communication and the sustainability of energy supply under NLOS link.

关键词： intelligent reflecting surface(IRS) joint optimization millimeter wave wireless information transmission(WIT) wireless power transfer(WPT)

Enhancement of comprehensive properties of Nb-Si based in-situ composites by Ho rare earth doping

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Rare Metals 2024年第9期43卷 4508-4520页

作者： wei wei qi Wang Rui-Run Chen Chao-Wen Zheng Yan-qing Su National Key Laboratory for Precision Hot Processing of Metals School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China

This study examines the microstructure,mechanical properties(with a focus on room-temperature toughness),and oxidation resistance of Ho-doped NbDSi based in-situ *** base alloy consists of the coarse primary Nb_(5)Si_(3)phase and the Nb_(5)Si_(3)+Nbss(Nb solid solution)eutectic *** doping influences the solidification *** the Ho doping is higher than0.2 at%,the alloys transform into eutectic *** can be solid-solved in trace amounts in the Nbss ***,most of Ho forms a stable Ho oxide phase,which alleviates oxygen contamination problem to some ***,the interface separation between Ho oxide and other phases reduces the plastic deformation ***,with 0.4 at%Ho doping,the K_(Q)value is18.03 MPa·m^(1/2),which is 31.1%higher than that of the base *** strength of the Ho-doped alloys does not deteriorate with an increase in ***,the large network-like Ho_(2)O_(3)in the 0.8Ho alloy causes a decrease in toughness and *** addition,the Ho oxide phase effectively blocks the inward oxygen *** 0.8 at%Ho doping,the oxidation mass gain per unit area is 10.16 mg·cm^(2),which is 39.7%lower than that of the base alloy.

关键词： Nb-Si based composites Rare earth elements Ho Microstructure Properties

High-Order Two-Scale Asymptotic Paradigm for the Elastodynamic Homogenization of Periodic Composites

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Acta Mechanica Solida Sinica 2024年第1期37卷 124-138页

作者： wei-Zhi Luo Mu He Liang Xia qi-Chang He State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China Laboratoire Modélisation et Simulation Multi-Echelle MSME UMR 8208 CNRSUniversite Gustave Eiffel77454 Marne-la-ValléeFrance

The classical two-scale asymptotic paradigm provides macroscopic and microscopic analyses for the elastodynamic homogenization of periodic composites based on the spatial or/and temporal variable,which offers an approximate framework for the asymptotic homogenization analysis of the motion ***,in this framework,the growing complexity of the homogenization formulation gradually becomes an obstacle as the asymptotic order *** such a context,a compact,fast,and accurate asymptotic paradigm is *** work reviews the high-order spatial two-scale asymptotic paradigm with the effective displacement field representation and optimizes the implementation by symmetrizing the tensor to be ***,the modified implementation gets rid of the excessive memory consumption required for computing the high-order tensor,which is demonstrated by representative one-and two-dimensional *** numerical results show that(1)the contrast of the material parameters between media in composites directly affects the convergence rate of the asymptotic results for the homogenization of periodic composites,(2)the convergence error of the asymptotic results mainly comes from the truncation error of the modified asymptotic homogenized motion equation,and(3)the excessive norm of the normalized wavenumber vector in the two-dimensional inclusion case may lead to a non-convergence of the asymptotic results.

关键词： Composites Homogenization Asymptotic analysis Dynamics Dispersion

Emergency management capacity assessment for urban rail transit-an example of Beijing Metro Line 13

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Transportation Safety and Environment 2024年第1期6卷 109-115页

作者： Jiao Liu Yun qi wei Wang School of Emergency Management and Safety Engineering China University of Mining&Technology(Beijing)Beijing 100083China China Safety Science Journal Editorial department China Occupational Safety and Health AssociationBeijing 100011China College of mechanical engineering and automation Liaoning University of TechnologyJinzhou 121001LiaoningChina

In order to improve the emergency management capability of urban rail transit system and reduce accidents during metro operation,an emergency management capability evaluation method combining analytic hierarchy process(AHP)and technique for order preference by similarity to ideal solution(TOPSIS)is *** on the Prevention Preparation Response Recovery(PPRR)model,factors influencing the emergency management capability of the urban rail transit system are summarized from the perspective of‘human,machine,environment and management’.Then,an emergency management capability evaluation index system containing of 20 secondary indicators is constructed in four stages:emergency prevention,emergency preparation,emergency response and emergency *** weights of indicators are calculated using the AHP method,and the closeness of each indicator to the optimal solution is analysed with the TOPSIS ***,take the Beijing Metro Line 13 as an example to investigate the level of emergency management capability of urban rail *** results show that the emergency management capability of Beijing’s urban rail transit system is‘well’,among which hazard prevention measures(0.31)and emergency response team(0.34)have a greater weight on the emergency management capability of rail *** model can more accurately assess the emergency management capability of urban rail transit and provide a basis for emergency management.

关键词： urban rail transit emergency management capability analytic hierarchy process(AHP) technique for order preference by similarity to ideal solution(TOPSIS) prevention preparation response recovery(PPRR)model

Wettability and corrosion behavior between alkaline slag from sodium smelting of vanadium-titanium magnetite and refractory substrates

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Journal of Iron and Steel Research International 2024年第6期31卷 1399-1410页

作者： Fei Zhao Zhi-wei Bian Hong-xin Zhao de-sheng Chen Zhang-fu Yuan Yu-lan Zhen Li-na Wang Tao qi Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China National Engineering Research Center of Green Recycling for Strategic Metal Resources Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Hebei Zhongke Tongchuang Vanadium&Titanium Technology Co. Ltd.Hengshui 053000HeheiChina

The sodium smelting of vanadium-titanium magnetite can achieve the comprehensive utilization of Fe,V,and ***,the generation of alkaline slag during this process may cause damage to refractory *** wettability and corrosion behavior of alkaline slag on three types of refractory(MgO-C,SiC,and high alumina refractory)substrates were investigated at temperatures up to 1200℃.The effects of duration on the wettability of molten slag on SiC substrates were also *** showed that the high alumina refractory exhibited better wettability with the molten slag than the others,and thus,it is easier to be *** results of scanning electron microscopy coupled with energy dispersive spectroscopy showed that MgO-C and high alumina refractory substrates were severely *** was a visible and regular interfacial reaction layer between the slag and SiC refractory substrate,which was produced by the redox reaction between the metal oxides in the slag and the SiC refractory *** the increase in holding time,the interface layer expands and silico-ferrite phases are generated at the *** redox reaction between Fe_(2)O_(3) and SiC substrate is the main reason for the *** comparing the differences in wettability and corrosion behavior between the alkaline slag from sodium smelting of vanadium-titanium magnetite and MgO-C,SiC and high alumina refractories,it is concluded that SiC refractory has good corrosion resistance to the *** oxides in the slag accelerate the oxidation rate of SiC refractory.

关键词： Wettability Corrosion Alkaline slag-Contact angle Vanadium-titanium magnetite Refractory

Research progress of tumor-associated macrophages in immune checkpoint inhibitor tolerance in colorectal cancer

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World Journal of Gastrointestinal Oncology 2024年第10期16卷 4064-4079页

作者： qi Fan Zheng-wei Fu Ming Xu Feng Lv Jia-Song Shi qi-qi Zeng de-Hai Xiong Intestinal Center Chongqing University Three Gorges HospitalChongqing 404000China department of Gastroenterology Nanjing Drum Tower HospitalThe Affiliated Hospital of Nanjing University Medical SchoolNanjing 210008Jiangsu ProvinceChina

The relevant mechanism of tumor-associated macrophages(TAMs)in the treatment of colorectal cancer patients with immune checkpoint inhibitors(ICIs)is discussed,and the application prospects of TAMs in reversing the treatment tolerance of ICIs are discussed to provide a reference for related *** a class of drugs widely used in clinical tumor immunotherapy,ICIs can act on regulatory molecules on cells that play an inhibitory role-immune checkpoints-and kill tumors in the form of an immune response by activating a variety of immune cells in the immune *** sensitivity of patients with different types of colorectal cancer to ICI treatment varies *** phenotype and function of TAMs in the colorectal cancer microenvironment are closely related to the efficacy of *** can regulate the phenotypic function of TAMs,and TAMs can also affect the tolerance of colorectal cancer to ICI *** play an important role in ICI resistance,and making full use of this target as a therapeutic strategy is expected to improve the immunotherapy efficacy and prognosis of patients with colorectal cancer.

关键词： Colorectal cancer Immune checkpoint inhibitor resistance Tumor microenvironment Tumor-associated macrophages Review