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Detailed seismic zoning of the East Kazakhstan region in the Republic of Kazakhstan

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Geodesy and Geodynamics 2024年第2期15卷 156-165页

作者： natalya V.Silacheva n.P.Stepanenko o.K.Kurilova A.D.Kudabayeva A.t.Danabayeva Institute of Seismology Ministry of Emergency SituationsAlmaty 050060Kazakhstan

Kazakhstan is currently drafting new construction regulations that comply with the major provisions of the *** regulations are created on the basis of seismic zoning maps of various degrees of detail,developed by our Institute of Seismology using a new methodological approach for *** article is about creating the first normative map of the Detailed Seismic Zoning on a probabilistic foundation for the Republic of Kazakhstan’s East Kazakhstan *** carried out the probabilistic assessment of seismic hazard using a methodology consistent with the main provisions of Eurocode 8and updated compared with that used in developing maps of Kazakhstan’s General Seismic Zoning and seismic microzoning of *** most thorough and current data accessible for the area under consideration were combined with contemporary analytical *** have been done to not only the databases being used but also the way seismic sources were shown,including active faults *** a scale of 1:1000000,precise seismic zoning maps of the East Kazakhstan region were created for two probabilities of exceedance:10%and 2%in 50 years in terms of peak ground accelerations and macroseismic *** obtained seismic hazard distribution is generally consistent with the General Seismic Zoning of Kazakhstan’s previous ***,because active faults were included and a thoroughly revised catalog was used,there are more pronounced zones of increased danger along the fault in the western part of the *** the west of the territory,acceleration values also increased due to a more accurate consideration of seismotectonic *** maps are the basis for developing new state building regulations of the Republic of Kazakhstan.

关键词： Probabilistic seismic hazard assessment Detailed seismic zoning Peak ground acceleration Microseismical intensity

Chebyshev polynomial-based Ritz method for thermal buckling and free vibration behaviors of metal foam beams

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 891-910页

作者： n.D.nGUyEn t.n.nGUyEn Faculty of Civil Engineering Ho Chi Minh City University of Technology and EducationHo Chi Minh City 71309Viet Nam Faculty of Engineering and technology Kien Giang UniversityChau Thanh 92000Viet Nam

this study presents the Chebyshev polynomials-based Ritz method to examine the thermal buckling and free vibration characteristics of metal foam *** analyses include three models for porosity distribution and two scenarios for thermal *** material properties are assessed under two conditions,i.e.,temperature dependence and temperature *** theoretical framework for the beams is based on the higher-order shear deformation theory,which incorporates shear deformations with higher-order *** governing equations are established from the Lagrange equations,and the beam displacement fields are approximated by the Chebyshev *** simulations are performed to evaluate the effects of thermal load,slenderness,boundary condition(BC),and porosity distribution on the buckling and vibration behaviors of metal foam *** findings highlight the significant influence of temperature-dependent(tD)material properties on metal foam beams'buckling and vibration responses.

关键词： Ritz method Chebyshev function buckling vibration metal foam beam higher-order beam theory(HoBt)

Data-Driven Direct Adaptive Risk-Sensitive Control of Stochastic Systems

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Journal of Systems Science & Complexity 2024年第4期37卷 1446-1469页

作者： QIAo nan LI tao School of Mathematical Sciences East China Normal UniversityShanghai 200241China Shanghai Key Laboratory of Pure Mathematics and Mathematical Practice School of Mathematical SciencesEast China Normal UniversityShanghai 200241China

the authors propose a data-driven direct adaptive control law based on the adaptive dynamic programming(ADP) algorithm for continuous-time stochastic linear systems with partially unknown system dynamics and infinite horizon quadratic risk-sensitive *** authors use online data of the system to iteratively solve the generalized algebraic Riccati equation(GARE) and to learn the optimal control law *** the case with measurable system noises,the authors show that the adaptive control law approximates the optimal control law as time goes *** the case with unmeasurable system noises,the authors use the least-square solution calculated only from the measurable data instead of the real solution of the regression equation to iteratively solve the *** authors also study the influences of the intensity of the system noises,the intensity of the exploration noises,the initial iterative matrix,and the sampling period on the convergence of the ADP ***,the authors present two numerical simulation examples to demonstrate the effectiveness of the proposed algorithms.

关键词： Adaptive dynamic programming direct adaptive control generalized algebraic Riccati equation risk-sensitive control

An indicator model for assessing community resilience to the CoVID-19 pandemic and its validation: A case study in Hong Kong

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Journal of Safety Science and Resilience 2024年第2期5卷 222-234页

作者： nan Liao Muhammad nawaz Departnent of Geography Faculty Art and Social SciencesSingapore 65166666Singapore

the CoVID-19 outbreak had a significant negative impact on the world,and the fifth wave of CoVID-19 in Hong Kong brought a considerable shock to Chinese *** is a growing call for more resilient ***,empirical evidence and validation of modeling studies of resilience indicators for urban community responses to the CoVID-19 pandemic still need to be *** this study,a resilience assessment indicator model comprising 4 subsystems,7 indicators,and 12 variables was developed to assess the resilience of Hong Kong communities in response to CoVID-19(i.e.,Resilience Index).Furthermore,this study utilized regression models such as geographically weighted regression(GWR)and multiscale GWR(MGWR)to validate the resilience model proposed in this study at the model and variable *** the regression model,the Resilience Index and the individual variables in the resilience model are explanatory variables,and the outcomes of the CoVID-19 pandemic(confirmed cases,confirmation rate,discharged cases,discharge rate)are dependent *** results showed that:(i)the resilience of Hong Kong communities to the CovID-19 pandemic was not strong in general and showed some clustered spatial distribution characteristics;(i)the validation results at the model level showed that the Resilience Index did not explain the consequences of the CovID-19 pandemic to a high degree;(ii)the validation results at the variable level showed that the MGWR model was the best at identifying the relationships between explanatory variables and the dependent variable;and(iv)compared with the model-level assessment results,the variable-level assessment explained the consequences of the CovID-19 pandemic better than the model level assessment *** above analysis and the spatial distribution maps of the resilience variables can provide empirically based and targeted insights for policymakers.

关键词： Resilience Community resilience CoVID-19pandemic Resilience assessment indicator model Resilience model validation MGWR

Envisioning Water-Resilient Cities through the Lens of Blue-Green-Grey Solutions

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Engineering 2024年第5期36卷 1-2页

作者： nan-Qi Ren Glen Daigger School of Civil and Environmental Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China State Key Laboratory of Urban Water Resource and Environment Harbin Institute of TechnologyHarbin 150090China Department of Civil and Environmental Engineering University of MichiganAnn ArborMI 48109USA

Cities are dynamic systems,and the urban water systems within them can be evolved to provide water services to both humans and the environment while also enhancing the broader urban *** is done by embracing innovation and technological advancement while focusing on increased service to the human population and the local and broader *** the contemporary era,characterized by the rise of low-carbon and intelligent technologies,the swift pace of socioeconomic expansion highlights the critical need to address issues of urban water security and environmental *** escalating resource and environmental constraints,adopting holistic blue-green-grey strategies becomes imperative for the sustainable governance of urban water *** integrated approach is needed to navigate the intricate challenges of urban water dynamics while fostering enhanced ecological performance and resilience.

关键词： services urban advancement

Distinct Electrical and Mechanical Responses of a Cu-10Fe Composite Prepared by Hot-Pressed Sintering and Post treatment

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 255-265页

作者： X.y.yue S.y.Peng X.Zhang C.n.He y.Z.tian Key Laboratory for Anisotropy and texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China School of Materials Science and Engineering and tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin300350China Research Centre for Metallic Wires Northeastern UniversityShenyang110819China

A Cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution *** hot-pressed sintered and solution treated materials were rolled and *** precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron *** contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the Cu-10wt%Fe *** Cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained excellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%IACS and softening temperature of 838 *** for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were *** findings provide a theoretical basis for designing high-performance Cu-based in-situ composites by post treatment.

关键词： Cu-Fe composite Hot-pressed sintering thermal stability Strength Electrical conductivity

Supposition of graphene stacks to estimate the contact resistance and conductivity of nanocomposites

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 663-676页

作者： y.ZARE M.t.MUnIR G.J.WEnG K.y.RHEE Biomaterials and tissue Engineering Research Group Department of Interdisciplinary TechnologiesBreast Cancer Research CenterMotamed Cancer InstituteTehran ***Iran College of Engineering and technology American University of the Middle EastEgaila 54200Kuwait Department of Mechanical and Aerospace Engineering Rutgers UniversityNew BrunswickNJ 08903U.S.A. Department of Mechanical Engineering(BK21 Four) College of EngineeringKyung Hee UniversityYongin 446701Republic of Korea

In this study,the effects of stacked nanosheets and the surrounding interphase zone on the resistance of the contact region between nanosheets and the tunneling conductivity of samples are evaluated with developed equations superior to those previously *** contact resistance and nanocomposite conductivity are modeled by several influencing factors,including stack properties,interphase depth,tunneling size,and contact *** developed model's accuracy is verified through numerous experimental *** further validate the models and establish correlations between parameters,the effects of all the variables on contact resistance and nanocomposite conductivity are ***,the contact resistance is primarily dependent on the polymer tunnel resistivity,contact area,and tunneling *** dimensions of the graphene nanosheets significantly influence the conductivity,which ranges from 0 S/m to90 S/*** increased number of nanosheets in stacks and a larger gap between them enhance the nanocomposite's ***,the thicker interphase and smaller tunneling size can lead to higher sample conductivity due to their optimistic effects on the percolation threshold and network efficacy.

关键词： graphene polymer composite stacked nanosheet tunneling conductivity contact resistance interphase

Bending results of graphene origami reinforced doubly curved shell

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Defence technology（防务技术） 2024年第5期35卷 198-210页

作者： nan yang yunhe Zou Mohammad Arefi School of Architecture and Civil Engineering Qiqihar UniversityQiqihar 161006HeilongjiangChina School of Mechanical Engineering Inner Mongolia University of TechnologyHohhot 010051Inner MongoliaChina Inner Mongolia Key Laboratory of Special Service Intelligent Robotics Hohhot 010051Inner MongoliaChina Faculty of Mechanical Engineering Department of Solid MechanicsUniversity of KashanKashan87317-51167Iran

the present work investigates higher order stress,strain and deformation analyses of a shear deformable doubly curved shell manufactures by a Copper(Cu)core reinforced with graphene origami auxetic metamaterial subjected to mechanical and thermal *** effective material properties of the graphene origami auxetic reinforced Cu matrix are developed using micromechanical models cooperate both material properties of graphene and Cu in terms of temperature,volume fraction and folding *** principle of virtual work is used to derive governing equations with accounting thermal *** numerical results are analytically obtained using navier's technique to investigate impact of significant parameters such as thermal loading,graphene amount,folding degree and directional coordinate on the stress,strain and deformation responses of the *** graphene origami materials may be used in aerospace vehicles and structures and defence technology because of their low weight and high stiffness.A verification study is presented for approving the formulation,solution methodology and numerical results.

关键词： Graphene origami Copper matrix Doubly curved Shear deformable Auxetic metamaterial

Spin-orbit interaction induced Casimir-Lifshitz torque between two-dimensional electron gases

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 134-142页

作者： Jia-nan Rong Liang Chen Kai Chang State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China School of Mathematics and Physics North China Electric Power UniversityBeijing 102206China School of Physics Zhejiang UniversityHangzhou 310027China College of Materials Science and opto-electronic technology University of Chinese Academy of SciencesBeijing 100049China

We investigate theoretically the Casimir interaction between two parallel two-dimensional electron gases(2DEGs)with Rashba and Dresselhaus spin-orbit interactions(SoIs),based on the quantum field *** derive an analytical expression for the polarization tensor and obtain the solution to the motion equation of the electromagnetic(EM)*** calculate the CasimirLifshitz torque(CLt)between two parallel 2DEGs with Rashba and Dresselhaus SoIs,which can be tuned by changing the relative strength between two *** anisotropic Casimir energy between 2DEGs caused by the interplay between the SoIs of 2DEGs offers a new origin of CLt and a new type of optoelectronic device.

关键词： Casimir torque two-dimensional electron gas spin-orbit interaction

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