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Self-Presentation onWeChat Moments and Ego Identity in Emerging Adults: The Role of Online Positive Feedback and Gender
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作者 Shuqing Wang Xiaorui Zhu +2 位作者 Xin Gao Jialing Deng Xiumei Yan 《International Journal of Mental Health Promotion》 2026年第3期183-204,共22页
Background:Emerging adulthood is a critical period for ego identity exploration and consolidation,and self-presentation on social media constitutes a salient online context for this developmental process.However,limit... Background:Emerging adulthood is a critical period for ego identity exploration and consolidation,and self-presentation on social media constitutes a salient online context for this developmental process.However,limited research has explored the associations between self-presentation on WeChat Moments and ego identity.This study aims to examine these associations,focusing on the mediating role of online positive feedback and the moderating role of gender.Methods:Using a three-wave longitudinal design,this study followed 767 Chinese college students(Mean age=18.96 years)through cluster sampling.Participants completed self-report questionnaires assessing self-presentation on WeChat Moments,online positive feedback,and ego identity status.Data analyses were conducted using mediation modeling and multi-group structural equation modeling.Results:Authentic self-presentation was positively associated with identity achievement and negatively associated with identity diffusion,whereas positive self-presentation was linked to higher levels of identity foreclosure.Online positive feedback played a significant mediating role in the associations between self-presentation strategies and identity statuses,and gender differences were observed in this mediating pathway.For both males and females,authentic self-presentation was associated with higher identity achievement through online positive feedback.However,indirect associations with identity foreclosure and diffusion were observed only among females:authentic self-presentation was linked to lower levels,whereas positive self-presentation was linked to higher levels of foreclosure and diffusion through online positive feedback.No comparable indirect associations were detected among males.Conclusions:Online positive feedback is closely linked to self-presentation strategies and ego identity statuses,with these associations varying by gender. 展开更多
关键词 Self-presentation on WeChat moments ego identity online positive feedback emerging adults
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Complex τ Electric Dipole Moment from GeV-Scale New Physics
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作者 Zhong-Lv Huang Xin-Yu Du +2 位作者 Xiao-Gang He Chia-Wei Liu Zi-Yue Zou 《Chinese Physics Letters》 2026年第3期28-33,共6页
Among the charged leptons,theτelectric dipole moment dτis the least constrained.We show that the Im[d_(τ)]imposes strong constraints on new physics that have yet to be discussed.Motivated in particular by the Super... Among the charged leptons,theτelectric dipole moment dτis the least constrained.We show that the Im[d_(τ)]imposes strong constraints on new physics that have yet to be discussed.Motivated in particular by the Super Tau-Charm Facility(STCF),which will provide a uniquely clean environment for precisionτ-physics,we study the momentum-transfer dependence of d_(τ)(q^(2))and compare the projected sensitivities of STCF and BelleⅡ.Our analysis shows that an axion-like coupling of the τ lepton can induce sizable real and imaginary components of the EDM.The predicted EDM values may approach the present experimental sensitivities,making them accessible to future measurements at Belle II and the STCF. 展开更多
关键词 momentum transfer dependence axion coupling new physics experimental sensitivities super tau charm facility LEPTON charged leptonsthe electric dipole moment gev scale new physics
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Moment Redistribution Effect of the Continuous Glass Fiber Reinforced Polymer-Concrete Composite Slabs Based on Static Loading Experiment 被引量:1
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作者 Zhao-Jun Zhang Wen-Wei Wang +4 位作者 Jing-Shui Zhen Bo-Cheng Li De-Cheng Cai Yang-Yang Du Hui Huang 《Structural Durability & Health Monitoring》 EI 2025年第1期105-123,共19页
This study aimed to investigate the moment redistribution in continuous glass fiber reinforced polymer(GFRP)-concrete composite slabs caused by concrete cracking and steel bar yielding in the negative bending moment z... This study aimed to investigate the moment redistribution in continuous glass fiber reinforced polymer(GFRP)-concrete composite slabs caused by concrete cracking and steel bar yielding in the negative bending moment zone.An experimental bending moment redistribution test was conducted on continuous GFRP-concrete composite slabs,and a calculation method based on the conjugate beam method was proposed.The composite slabs were formed by combining GFRP profiles with a concrete layer and supported on steel beams to create two-span continuous composite slab specimens.Two methods,epoxy resin bonding,and stud connection,were used to connect the composite slabs with the steel beams.The experimental findings showed that the specimen connected with epoxy resin exhibited two moments redistribution phenomena during the loading process:concrete cracking and steel bar yielding at the internal support.In contrast,the composite slab connected with steel beams by studs exhibited only one-moment redistribution phenomenon throughout the loading process.As the concrete at the internal support cracked,the bending moment decreased in the internal support section and increased in the midspan section.When the steel bars yielded,the bending moment further decreased in the internal support section and increased in the mid-span section.Since GFRP profiles do not experience cracking,there was no significant decrease in the bending moment of the mid-span section.All test specimens experienced compressive failure of concrete at the mid-span section.Calculation results showed good agreement between the calculated and experimental values of bending moments in the mid-span section and internal support section.The proposed model can effectively predict the moment redistribution behavior of continuous GFRP-concrete composite slabs. 展开更多
关键词 moment redistribution GFRP-concrete composite slabs bending moment experimental study analysis model
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Moment analysis of bio-inspired stochastic energy harvesters under wind conditions
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作者 WANG Kang-Ning HUANG Dong-Mei HAN Jia-Le 《四川大学学报(自然科学版)》 北大核心 2025年第1期246-256,共11页
To further understand the performance of the energy harvesters under the influence of the wind force and the random excitation,this paper investigates the stochastic response of the bio-inspired energy harvesters subj... To further understand the performance of the energy harvesters under the influence of the wind force and the random excitation,this paper investigates the stochastic response of the bio-inspired energy harvesters subjected to Gaussian white noise and galloping excitation,simulating the flapping pattern of a seagull and its interaction with wind force.The equivalent linearization method is utilized to convert the original nonlinear model into the Itôstochastic differential equation by minimizing the mean squared error.Then,the second-order steady-state moments about the displacement,velocity,and voltage are derived by combining the moment analysis theory.The theoretical results are simulated numerically to analyze the stochastic response performance under different noise intensities,wind speeds,stiffness coefficients,and electromechanical coupling coefficients,time domain analysis is also conducted to study the performance of the harvester with different parameters.The results reveal that the mean square displacement and voltage increase with increasing the noise intensity and wind speed,larger absolute values of stiffness coefficient correspond to smaller mean square displacement and voltage,and larger electromechanical coupling coefficients can enhance the mean square voltage.Finally,the influence of wind speed and electromechanical coupling coefficient on the stationary probability density function(SPDF)is investigated,revealing the existence of a bimodal distribution under varying environmental conditions. 展开更多
关键词 Bio-inspired energy harvesters Gaussian white noise Equivalent linearization method Steadystate moment
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Moments of Friendship
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作者 HU FAN 《ChinAfrica》 2025年第12期33-35,共3页
Beyond business,the CIIE is a vibrant platform where diverse cultures meet,share,and shine The eighth China International Import Expo,held from 5 to 10 November in Shanghai,once again served as a premier stage for exh... Beyond business,the CIIE is a vibrant platform where diverse cultures meet,share,and shine The eighth China International Import Expo,held from 5 to 10 November in Shanghai,once again served as a premier stage for exhibitors from around the world to showcase their distinctive cultures.From food and clothing to a wide array of arts,the more than 900,000 visitors were treated to a rich tapestry of cultural experiences from across the globe. 展开更多
关键词 momentS FRIENDSHIP IMPORT EXPO BUSINESS China BEYOND CIIE
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Moments of Dirichlet L-Functions
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作者 HUANG Bing-rong HUANG Jun-hao 《Chinese Quarterly Journal of Mathematics》 2025年第4期360-371,共12页
In this paper, we establish asymptotic formulas for a cubic moment of Dirichlet L-functions restricted to a coset, as well as for a mixed moment of Dirichlet L-functions and twists of GL(2) L-functions along a coset. ... In this paper, we establish asymptotic formulas for a cubic moment of Dirichlet L-functions restricted to a coset, as well as for a mixed moment of Dirichlet L-functions and twists of GL(2) L-functions along a coset. Our main tool is a power-saving estimate of bilinear forms of hyper-Kloosterman sums due to Kowalski–Michel–Sawin. 展开更多
关键词 moment TWIST Dirichlet L-functions COSET
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Short-Term Spillover Effects in High-order Moments of Stocks, Foreign Currency Exchange and Bitcoin with Intraday Data
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作者 Xinying He 《Proceedings of Business and Economic Studies》 2025年第3期172-181,共10页
This paper employs Granger causality analysis and the generalized impulse response function(GIRF)to study the higher-order moment spillover effects among Bitcoin,stock markets,and foreign exchange markets in the U.S.U... This paper employs Granger causality analysis and the generalized impulse response function(GIRF)to study the higher-order moment spillover effects among Bitcoin,stock markets,and foreign exchange markets in the U.S.Using intraday high-frequency data,the research focuses on the interactions across higher-order moments,including volatility,jumps,skewness,and kurtosis.The results reveal significant bidirectional spillover effects between Bitcoin and traditional financial assets,particularly in terms of volatility and jump behavior,indicating that the cryptocurrency market has become a crucial component of global financial risk transmission.This study provides new theoretical perspectives and policy recommendations for global asset allocation,market regulation,and risk management,underscoring the importance of proactive management measures in addressing the complex risk interactions between cryptocurrencies and traditional financial markets. 展开更多
关键词 Higher-order moments Intraday data Spillover effects Bitcoin Risk management
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Moment tensor inversion of mining-induced seismic events and forward modeling of critical fault slip to prevent rockbursts
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作者 Jiefang Song Caiping Lu +4 位作者 Arno Zang Derek Elsworth Xiufeng Zhang Qingxin Qi Chunhui Song 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第5期2987-3000,共14页
In this study,we employed Bayesian inversion coupled with the summation-by-parts and simultaneousapproximation-term(SBP-SAT)forward simulation method to elucidate the mechanisms behind mininginduced seismic events cau... In this study,we employed Bayesian inversion coupled with the summation-by-parts and simultaneousapproximation-term(SBP-SAT)forward simulation method to elucidate the mechanisms behind mininginduced seismic events caused by fault slip and their potential effects on rockbursts.Through Bayesian inversion,it is determined that the sources near fault FQ14 have a significant shear component.Additionally,we analyzed the stress and displacement fields of high-energy events,along with the hypocenter distribution of aftershocks,which aided in identifying the slip direction of the critically stressed fault FQ14.We also performed forward modeling to capture the complex dynamics of fault slip under varying friction laws and shear fracture modes.The selection of specific friction laws for fault slip models was based on their ability to accurately replicate observed slip behavior under various external loading conditions,thereby enhancing the applicability of our findings.Our results suggest that the slip behavior of fault FQ14 can be effectively understood by comparing different scenarios. 展开更多
关键词 ROCKBURST Fault slip moment tensor inversion Friction law
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Characters:A Bond Connecting Cultures——China Tour:Anyang Moments Themed Event Held in Yinxu Museum
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《International Understanding》 2025年第3期47-52,共6页
On the morning of 13th September,the themed event Characters:A Bond Connecting Cultures--China Tour:Anyang Moments was held at Yinxu Museum(Museum of the Ruins of the Shang Dynasty).The event was co-hosted by the Chin... On the morning of 13th September,the themed event Characters:A Bond Connecting Cultures--China Tour:Anyang Moments was held at Yinxu Museum(Museum of the Ruins of the Shang Dynasty).The event was co-hosted by the China NGO Network for International Exchanges(CNIE)and Anyang Municipal People's Government. 展开更多
关键词 China ngo network International exchanges CNIEN Shang dynasty Anyang moments China tour Yinxu museum
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Secure and Invisible Dual Watermarking for Digital Content Based on Optimized Octonion Moments and Chaotic Metaheuristics
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作者 Ahmed El Maloufy Mohamed Amine Tahiri +2 位作者 Ahmed Bencherqui Hicham Karmouni Mhamed Sayyouri 《Computers, Materials & Continua》 2025年第12期5789-5822,共34页
In the current digital context,safeguarding copyright is a major issue,particularly for architectural drawings produced by students.These works are frequently the result of innovative academic thinking combining creat... In the current digital context,safeguarding copyright is a major issue,particularly for architectural drawings produced by students.These works are frequently the result of innovative academic thinking combining creativity and technical precision.They are particularly vulnerable to the risk of illegal reproduction when disseminated in digital format.This research suggests,for the first time,an innovative approach to copyright protection by embedding a double digital watermark to address this challenge.The solution relies on a synergistic fusion of several sophisticated methods:Krawtchouk Optimized Octonion Moments(OKOM),Quaternion Singular Value Decomposition(QSVD),and Discrete Waveform Transform(DWT).To improve watermark embedding,the biologically inspired algorithm Chaos-White Shark Optimization(CWSO)is used,which allows dynamically adapting essential parameters such as the scaling factor of the insertion.Thus,two watermarks are inserted at the same time:an institutional logo and a student image,encoded in the main image(the architectural plan)through octonionic projections.This allows minimizing the amount of data to be integrated while increasing resistance.The suggested approach guarantees a perfect balance between the discreetness of the watermark(validated by PSNR indices>47 dB and SSIM>0.99)and its resistance to different attacks(JPEG compression,noise,rotation,resizing,filtering,etc.),as proven by the normalized correlation values(NC>0.9)obtained following the extraction.Therefore,this method represents a notable progress for securing academic works in architecture,providing an effective,discreet and reversible digital protection,which does not harm the visual appearance of the original works. 展开更多
关键词 Double digital watermarks krawtchouk moments chaos-white shark OPTIMIZATION
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Determination of radiated energy and energy-moment ratio for the 2025 Dingri,Xizang M6.8 earthquake
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作者 Yixiao Zhang Ruifeng Liu +1 位作者 Zibo Wang Zan Li 《Earthquake Science》 2025年第6期564-574,共11页
Radiated seismic energy is a quantitative characteristic of an earthquake that depends not only on the initial and final stresses,but also on the rupture history,and reflects the dynamic characteristics of the source.... Radiated seismic energy is a quantitative characteristic of an earthquake that depends not only on the initial and final stresses,but also on the rupture history,and reflects the dynamic characteristics of the source.The seismic wave energy radiated per unit of seismic moment,or energy-moment ratio,represents the balance between the stress drop,source rupture velocity,and variation in the shear wave velocity.Earthquakes with a high energy-moment ratio thus release strain energy more rapidly.The accurate and rapid determination of radiated seismic energy and the energy-moment ratio play an important role in seismic hazard assessment,quantitative earthquake research,and engineering seismology research.In this study,waveform data from the Global Seismographic Network were used to measure the dynamic source parameters of an earthquake that occurred on January 7,2025,in Dingri,Xizang,with the radiated energy,energy-moment ratio,slowness parameter,and apparent stress investigated.Static source parameters such as the seismic moment and moment magnitude were also determined.The main results were as follows:(1)the radiated energy of the earthquake was 9.73×10^(14)J,corresponding to an energy magnitude ME of 7.1,with a source rupture time of 24 s;(2)the focal mechanism was normal faulting,with the seismic moment of 4.98×10^(19)N·m corresponding to a moment magnitude MW of 7.1.Nodal plane I was focused at 191°/32°/-67°while planeⅡwas at 344°/60°/-104°,and the centroid depth was 12.3 km;(3)the energy-moment ratio of the earthquake was 1.95×10^(-5),the slowness parameter was-4.71,and the apparent stress was 0.59 MPa.The energy-moment ratio was thus higher than the average for normal fault earthquakes on the Chinese mainland.In conclusion,the results indicated that the 2025 earthquake was a normal fault earthquake with relatively high energy release efficiency and significant potential for damage to local buildings and the infrastructure,as verified by the severe damage to ground structures and significant casualties nearby. 展开更多
关键词 radiated seismic energy energy magnitude seismic moment energy-moment ratio apparent stress
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Study of a Moment Suspension Mechanism for Off-Road Operation of a Multi-Terrain Mobile Robot
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作者 Buyun Wang Menglong Jiang +4 位作者 Bing Zhao Wen Peng Yi Liang Jun Cheng Hanchun Hu 《Chinese Journal of Mechanical Engineering》 2025年第5期627-649,共23页
To effectively improve the adaptability and traversal abilities of a multi-terrain mobile robot under the dynamic excitation of multiple roads,we explore the mobile robot’s vibration and joint driving output stall ca... To effectively improve the adaptability and traversal abilities of a multi-terrain mobile robot under the dynamic excitation of multiple roads,we explore the mobile robot’s vibration and joint driving output stall caused by the dynamic excitation of the road spectrum function and analyze techniques for reducing the vibration and enhancing the driving moment of a four-wheel differential-speed mobile robot.A double-wishbone vibration reduction suspension and a moment compensator were designed for a multi-terrain mobile robot by theoretically describing its suspensionwheel-road dynamics.Also,the mobile robot’s road adaptability and traversal abilities were mathematically characterized under dynamic excitation.Co-simulation in ADAMS-MATLAB/Simulink is performed such as the harsh condition of in situ rotation and outdoor experimental schemes are implemented in which the experimental data are analyzed.The experimental result verifies the correctness of the theoretical analysis,as well as the effectiveness of the vibration reduction suspension and the moment compensator.The compatibility of the mobile robot’s driving mechanisms with road traversal abilities has been improved under various terrain conditions in complex field operation scenarios. 展开更多
关键词 Multi-terrain mobile robot Road passability Suspension mechanism moment compensator
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Asymmetric fission of^(180)Hg and the role of hexadecapole moment
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作者 Yang Su Yong-Jing Chen +3 位作者 Ze-Yu Li Li-Le Liu Guo-Xiang Dong Xiao-Bao Wang 《Nuclear Science and Techniques》 2025年第12期264-272,共9页
In this study,the fission properties of^(180)Hg were investigated based on Skyrme density functional theory.The impact of the high-order hexadecapole moment(q_(40))was observed at large deformations.With the q_(40)con... In this study,the fission properties of^(180)Hg were investigated based on Skyrme density functional theory.The impact of the high-order hexadecapole moment(q_(40))was observed at large deformations.With the q_(40)constraint,smooth and continuous potential energy surfaces could be obtained.In particular,the hexadecapole moment constraint is essential for obtaining appropriate scission configurations.The static fission path based on the PES supports the asymmetric fission of^(180)Hg.The asymmetric distribution of the fission yields of^(180)Hg was reproduced by the time-dependent generator coordinate method and agreed well with the experimental data. 展开更多
关键词 Nuclear fission Density functional theory Hexadecapole moment Potential energy surface Mass distribution
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Stabilizing Agricultural Robots Against Intense Rollovers With Control Moment Gyro
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作者 Long‐Long Wang Zhi‐Zhu He Zhen Li 《SmartSys》 2025年第2期1-13,共13页
Rollover accidents involving agricultural wheeled robots,accompanied by severe mechanical impacts,pose serious threats to operational safety and reduce functional efficiency.To address this issue,an active rollover pr... Rollover accidents involving agricultural wheeled robots,accompanied by severe mechanical impacts,pose serious threats to operational safety and reduce functional efficiency.To address this issue,an active rollover prevention strategy is proposed,utilizing a single‐gimbal control moment gyro(SGCMG),to stabilize typical agricultural robots and prevent potential rollovers.To match the free oscillation of the pivot front axle,a novel recovery torque model of the coupled robot‐SGCMG system is established,in which two patterns are introduced to refine the rollover process with uncertain parameters.Additionally,a lateral stability index is adopted and analyzed to assess the hazard level of potential rollovers.Aimed at handling uncertain parameters and hazard levels,an adaptive backstepping control strategy is developed for real‐time anti‐rollover implementation.Within this strategy,control gains are adaptively tuned based on theoretical derivations,thereby suppressing rollover tendency while minimizing tuning effort.For verification,a scaled experimental platform,designed according to similarity theory,is constructed to ensure safety of personnel and equipment.Experimental results show that the proposed method can precisely regulate the output torque of the gyro,rapidly and effectively mitigating the risk of imminent rollover.This method provides a promising solution for wheeled robot stability and a theoretical basis for advanced safety control in agricultural robotics. 展开更多
关键词 adaptive backstepping control agricultural robots control moment gyroscope robot rollover robot safety
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Magnetic Tracking System with Capability of Automatic Magnetic Moment Measurement
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作者 TIAN Siyu GAO Jinyang +2 位作者 HUANG Peng MA Xinyu MA Ziyu 《Journal of Shanghai Jiaotong university(Science)》 2025年第4期646-657,共12页
Magnetic tracking technologies have a promising application in detecting the real-time position andattitude of a capsule endoscope.However,most of them need to measure the magnetic moment of a permanentmagnet(PM)embed... Magnetic tracking technologies have a promising application in detecting the real-time position andattitude of a capsule endoscope.However,most of them need to measure the magnetic moment of a permanentmagnet(PM)embedded in the capsule accurately in advance,which can cause inconvenience to practical application.To solve this problem,this paper proposes a magnetic tracking system with the capability of measuring themagnetic moment of the PM automatically.The system is constructed based on a 4×4 magnetic sensor array,whose sensing data is analyzed to determine the magnetic moment by referring to a magnetic dipole model.Withthe determined magnetic moment,a method of fusing the linear calculation and Levenberg-Marquardt algorithmsis proposed to determine the 3D position and 2D attitude of the PM.The experiments verified that the proposedsystem can achieve localization errors of 0.48 mm,0.42 mm,and 0.83 mm and orientation errors of 0.66◦,0.64◦,and 0.87◦for a PM(∅10 mm×10 mm)at vertical heights of 5 cm,10 cm,and 15 cm from the magnetic sensorarray,respectively. 展开更多
关键词 permanent magnet magnetic moment measurement optimized Levenberg-Marquardt algorithm MAG3110 magnetic sensor tracking system
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Isogeometric Collocation Method for Random Field Discretization Based on Adaptive Moment Abscissae
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作者 Zhenyu Liu Deshang Peng +3 位作者 Minglong Yang Jin Cheng Chan Qiu Jianrong Tan 《Chinese Journal of Mechanical Engineering》 2025年第6期272-286,共15页
The discretization of random fields is the first and most important step in the stochastic analysis of engineering structures with spatially dependent random parameters.The essential step of discretization is solving ... The discretization of random fields is the first and most important step in the stochastic analysis of engineering structures with spatially dependent random parameters.The essential step of discretization is solving the Fredholm integral equation to obtain the eigenvalues and eigenfunctions of the covariance functions of the random fields.The collocation method,which has fewer integral operations,is more efficient in accomplishing the task than the timeconsuming Galerkin method,and it is more suitable for engineering applications with complex geometries and a large number of elements.With the help of isogeometric analysis that preserves accurate geometry in analysis,the isogeometric collocation method can efficiently achieve the results with sufficient accuracy.An adaptive moment abscissa is proposed to calculate the coordinates of the collocation points to further improve the accuracy of the collocation method.The adaptive moment abscissae led to more accurate results than the classical Greville abscissae when using the moment parameter optimized with intelligent algorithms.Numerical and engineering examples illustrate the advantages of the proposed isogeometric collocation method based on the adaptive moment abscissae over existing methods in terms of accuracy and efficiency. 展开更多
关键词 Random Random discretization Isogeometric collocation method Isogeometric Galerkin method Greville abscissae Adaptive moment abscissae
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Complete q-Order Moment Convergence of Moving Average Processes Generated by Negatively Dependent Random Variables under Sub-Linear Expectations
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作者 Mingzhou XU 《Journal of Mathematical Research with Applications》 2025年第3期395-410,共16页
Assume that{a_(i),−∞<i<∞}is an absolutely summable sequence of real numbers.We establish the complete q-order moment convergence for the partial sums of moving average processes{X_(n)=Σ_(i=−∞)^(∞)a_(i)Y_(i+... Assume that{a_(i),−∞<i<∞}is an absolutely summable sequence of real numbers.We establish the complete q-order moment convergence for the partial sums of moving average processes{X_(n)=Σ_(i=−∞)^(∞)a_(i)Y_(i+n),n≥1}under some proper conditions,where{Yi,-∞<i<∞}is a doubly infinite sequence of negatively dependent random variables under sub-linear expectations.These results extend and complement the relevant results in probability space. 展开更多
关键词 moving average processes negatively dependent random variables complete moment convergence sub-linear expectations
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Experimental Study on Shear Mechanical Properties of Light Composite Bridge in Bending Moment Zone
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作者 Han Zhang Shuwen Deng 《Journal of Architectural Research and Development》 2025年第5期8-13,共6页
This study conducted shear resistance tests on steel-UHPC composite beams,focusing on structural stiffness changes during the test process,strain analysis of UHPC panels,internal reinforcement bars,steel structures,an... This study conducted shear resistance tests on steel-UHPC composite beams,focusing on structural stiffness changes during the test process,strain analysis of UHPC panels,internal reinforcement bars,steel structures,and shear connectors,as well as the failure processes and modes of UHPC panels and the structure.Through theoretical analysis,the contribution of UHPC panels to the overall vertical shear resistance capability was clarified.A shear load-bearing capacity calculation method was established,thereby considering the combined beam shear bearing capacity calculation formula of the UHPC panel and the steel beam web. 展开更多
关键词 Steel-UHPC composite beam Positive moment zone Shear resistance test Bridge design theory and calculation method
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T-S Fuzzy Based Model Predictive Control Method for the Direct Yaw Moment Control System Design
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作者 Faan Wang Xinqi Liu +3 位作者 Guodong Yin Liwei Xu Jinhao Liang Yanbo Lu 《Chinese Journal of Mechanical Engineering》 2025年第5期379-389,共11页
Distributed drive electric vehicles(DDEVs)endow the ability to improve vehicle stability performance through direct yaw-moment control(DYC).However,the nonlinear characteristics pose a great challenge to vehicle dynam... Distributed drive electric vehicles(DDEVs)endow the ability to improve vehicle stability performance through direct yaw-moment control(DYC).However,the nonlinear characteristics pose a great challenge to vehicle dynamics control.For this purpose,this paper studies the DYC through the Takagi-Sugeno(T-S)fuzzy-based model predictive control to deal with the nonlinear challenge.First,a T-S fuzzy-based vehicle dynamics model is established to describe the time-varying tire cornering stiffness and vehicle speeds,and thus the uncertain parameters can be represented by the norm-bounded uncertainties.Then,a robust model predictive control(MPC)is developed to guarantee vehicle handling stability.A feasible solution can be obtained through a set of linear matrix inequalities(LMIs).Finally,the tests are conducted by the Carsim/Simulink joint platform to verify the proposed method.The comparative results show that the proposed strategy can effectively guarantee the vehicle’s lateral stability while handling the nonlinear challenge. 展开更多
关键词 Distributed drive electric vehicles Direct yaw moment control Lateral stability Robust model predictive control
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煤岩张剪裂隙震源机制及应力反演方法
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作者 王恩元 张力 +2 位作者 王笑然 刘晓斐 李楠 《煤炭学报》 北大核心 2026年第1期293-313,共21页
精准监测与定量反演煤岩裂隙形态及应力场分布特征,是揭示冲击地压演化过程及致灾机理的科学基础,更是解决深地工程动力灾变演化问题的重要手段。以位移不连续理论为基础建立不同破裂类型的裂隙震源模型,通过修正Bott假设,提出适用于张... 精准监测与定量反演煤岩裂隙形态及应力场分布特征,是揭示冲击地压演化过程及致灾机理的科学基础,更是解决深地工程动力灾变演化问题的重要手段。以位移不连续理论为基础建立不同破裂类型的裂隙震源模型,通过修正Bott假设,提出适用于张剪裂隙类型的应力反演模型,并融合格里菲斯与摩尔-库仑准则构建复合破裂判据,实现真实裂隙面的有效识别,并以震源机制参数及应力场参数的最优适配为目标,进一步提出裂隙震源与应力联合迭代反演方法,并开展了实验室尺度的煤岩破坏监测反演的实践应用。结果表明:偏移角α可有效区分张拉、剪切及压缩等破坏类型,提出基于张剪复合失效准则的裂隙面与应力迭代求解方法,有效选取真实裂隙面提高应力反演精度,建立裂隙震源与应力的联合交替迭代模型,可有效减少理论滑移方向与真实滑移方向的偏差。在煤岩三点弯曲试验过程中,偏移角α主要处于0°~20°,表明破裂微裂纹主要为张剪复合类型,利用应力反演模型求得最大主应力σ_(1)为拉应力,中间主应力σ_(2)和最小主应力σ_(3)为压应力,应力形状比平均值为0.87,表明σ_(1)占主导作用,σ_(2)和σ_(3)几乎相等,符合三点弯曲试样的受力状态,应力分布影响了试样裂纹运动方向主要为沿X轴方向的张拉分离,并促进了裂纹取向为沿Y轴方向的发育扩展。另外,应力旋转作用导致裂纹面取向在Y轴方向的分量被减小,裂纹运动方向与X轴方向的夹角增大,而这一改变随着应力旋转角度的增大得到加强。利用裂隙震源与应力联合迭代反演方法对应力反演过程进行优化,理论滑移方向与真实滑移方向之间的平均滑移偏差角依次降低了33.91%、79.86%和94.12%。将提出的张剪震源应力反演方法与VAVRYČUK方法进行对比,应力的形状比噪声误差率最大降低了6.49%,三向应力反演精度平均提升了15%~40%,研究成果可为煤岩体动力灾变演化研究提供一种科学方法,为深地工程冲击地压孕育机制解析与灾害预警提供新的理论支撑。 展开更多
关键词 矩张量 震源机制 联合迭代反演 应力分布 应力旋转
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