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用井下记录为地震与海啸预警系统估计震级

世界地震译丛 2013年第5期44卷 52-63页

作者： A.Eshaghi K.F.Tiampo H.ghofrani G.m.Atkinson 王芙容(译) 不详中国地震台网中心

给出了地震动预测方程（GmPE）估计地震与海啸预警系统震级的新应用。该技术结合了井下强震记录和地面记录，所用的数据均来自基岩强震观测台网（KiK—net）台站。我们分析了由日本地球科学与防灾研究所（NIED）提供的KiK—net台网1998... 详细信息

给出了地震动预测方程（GmPE）估计地震与海啸预警系统震级的新应用。该技术结合了井下强震记录和地面记录，所用的数据均来自基岩强震观测台网（KiK—net）台站。我们分析了由日本地球科学与防灾研究所（NIED）提供的KiK—net台网1998～2010年期间记录的矩震级（m）5．0～8．1地震的强地震动数据。我们使用井下地震仪记录的地震动峰值加速度（PGA）大于10cm／s。的2160个强震动加速度图和地面地震仪记录的地震动峰值加速度大于80cm／s。的890个波形，来推导日本的地震动峰值加速度和地震动峰值速度（PGV）的地震动预测方程。这些地震动预测方程是确定区域震级的基础。我们分别对井下记录和地面记录确定了由地震动峰值加速度值预测的震级（mp。n）和由地震动峰值速度值预测的震级（m诧v）。只要每个事件至少有20个可用记录，mrca和mP、，就与事件的矩震级具有很强的相关性。结果显示由井下数据得到的mPGv在估计的震级中标准偏差最小，是对地震震级的精确早期评估。我们认为，加入强震发生后迅即得到的井下强地震动记录显著提高了地震震级估计的精度，改善了地震和海啸预警系统的性能。

关键词：海啸预警系统井下地震仪强地震动矩震级估计地震动峰值加速度预测方程强震记录

冷轧及退火对310S奥氏体不锈钢的微观结构和组织的影响:基于X射线和电子背散射衍射分析

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Journal of Central South University 2023年第3期30卷 763-785页

作者： R.b.HEIDARI m.ESKANDARI m.YEGANEH Department of materials Engineering Faculty of EngineeringShahid Chamran University of AhvazAhvaz ***Iran

本文研究了热处理对310S奥氏体不锈钢的微观结构和组织的影响。对样品材料进行冷轧,使其厚度分别减少20%、50%和90%,然后在1023、1223和1323 K下退火5、15和30 min。在厚度减少20%后,奥氏体内产生孪晶,且可观察到形变诱发的α’马氏体,... 详细信息

本文研究了热处理对310S奥氏体不锈钢的微观结构和组织的影响。对样品材料进行冷轧,使其厚度分别减少20%、50%和90%,然后在1023、1223和1323 K下退火5、15和30 min。在厚度减少20%后,奥氏体内产生孪晶,且可观察到形变诱发的α’马氏体,孪晶的体积分数大于α’马氏体。当厚度变化由50%增加到90%,α’马氏体的体积分数由11%增加到69%,孪晶被α’马氏体取代。发生形变后奥氏体相主要为brass、Goss和S织构,α’马氏体的主要纹理为R-Cu、R-cube、F和E组份。随着形变量增大,brass织构增加,Goss织构减少。退火过程中,马氏体向奥氏体转变,并发生了再结晶,使Goss和brass再结晶织构的体积分数增加。材料退火后的结构与冷轧后的大致相同。1223 K下退火5 min的马氏体转变速度明显高于1023 K下的。在1023 K下退火5 min,由于马氏体不完全转变和初级再结晶,未能检测到等轴组织。获得超细晶粒组织的最佳退火温度为1023 K,退火时间为15 min。在1173 K和1273 K时出现快速再结晶和晶粒生长。

关键词： 310S不锈钢形变退火电子背散射衍射微观结构组织

Linear Precoder Design for Correlated Rician Fading Channel Under Imperfect CSI

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中国通信:英文版 2023年第9期20卷 160-170页

作者： S.b.m.Priya School of Electrical and Electronics Engineering SASTRA Deemed UniversityThanjavur 613401India

In this paper,we have modeled a linear precoder for indoor multiuser multiple input multiple output(mU-mImO)system with imperfect channel state information(CSI)at transmitter.The Rician channel is presumed to be mutually coupled and spatially,temporarily correlated.The imperfection with CSI is primarily due to the channel estimation error at receiver and feedback delay amidst the receiver and transmitter in CSI transmission.Along with,the insufficient spacing between the antenna at transmitter and receiver persuades mutual coupling(mC)among the array elements.In addition,the mImO channel is presumed to be jointly correlated(Weichselberger correlation model).When we look back on the existing precoder design,it considered spatial correlation alone disregarding joint correlation of antenna array elements.With all above assumption,we have designed a linear precoder which minimizes mean squared error(mSE)subjected to total transmit power constraint for mUmImO system.The simulation results proven that proposed precoder shows substantial enhancement in bit error rate(bER)performance in comparison with the existing technique.The mathematical analysis corroborates the simulation results.

关键词： channel estimation error feedback delay mmSE linear precoder mutual coupling spatial cor-relation Weichselberger correlation model

Effect of periodic heat transfer on the transient thermal behavior of a convective-radiative fully wet porous moving trapezoidal fin

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Applied mathematics and mechanics(English Edition) 2023年第4期44卷 653-668页

作者： b.J.GIREESHA m.L.KEERTHI Department of PG Studies and Research in mathematics Kuvempu UniversityShankaraghatta 577451India

A moving trapezoidal profiled convective-radiative porous longitudinal fin wetted in a single-phase fluid is considered in the current article.The periodic variation in the fin base temperature is taken into account along with the temperature sensitive thermal conductivity and convective heat transfer coefficients.The modeled problem,which is resolved into a non-linear partial differential equation(PDE),is made dimensionless and solved by employing the finite difference method(FDm).The results are displayed through graphs and discussed.The effects of amplitude,frequency of oscillation,wet nature,Peclet number,and other relevant quantities on the distribution of temperature through the fin length and with the dimensionless time are investigated.It is deciphered that the periodic heat transfer gives rise to the wavy nature of the fin thermal profile against time.The analysis is beneficial in the design of fin structures for applications like solar collectors,space/airborne applications,and refrigeration industries.

关键词： convection fully wet porous fin trapezoidal profile moving fin unsteady periodic thermal condition

Quantum correlations and entanglement in coupled optomechanical resonators with photon hopping via Gaussian interferometric power analysis

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Chinese Physics b 2024年第5期33卷 204-211页

作者： Y.Lahlou b.maroufi m.Daoud LPHE-mS Department of PhysicsFaculty of SciencesMohammed V UniversityRabatMorocco LPmS Department of PhysicsFaculty of SciencesIbn Tofail UniversityKénitraMorocco

Quantum correlations that surpass entanglement are of great importance in the realms of quantum information processing and quantum computation.Essentially,for quantum systems prepared in pure states,it is difficult to differentiate between quantum entanglement and quantum correlation.Nonetheless,this indistinguishability is no longer holds for mixed states.To contribute to a better understanding of this differentiation,we have explored a simple model for both generating and measuring these quantum correlations.Our study concerns two macroscopic mechanical resonators placed in separate Fabry–Pérot cavities,coupled through the photon hopping process.this system offers a comprehensively way to investigate and quantify quantum correlations beyond entanglement between these mechanical modes.The key ingredient in analyzing quantum correlation in this system is the global covariance matrix.It forms the basis for computing two essential metrics:the logarithmic negativity(E_(N)^(m))and the Gaussian interferometric power(P_(G)^(m)).These metrics provide the tools to measure the degree of quantum entanglement and quantum correlations,respectively.Our study reveals that the Gaussian interferometric power(P_(G)^(m))proves to be a more suitable metric for characterizing quantum correlations among the mechanical modes in an optomechanical quantum system,particularly in scenarios featuring resilient photon hopping.

关键词： quantum correlations entanglement Gaussian interferometric power logarithmic negativity optomechanics photon hopping

The new wave of p75 neurotrophin receptor targeted therapies

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Neural Regeneration Research 2022年第1期17卷 95-96页

作者： Amanda m.Crooks Rick b.meeker UNC School of medicine University of North CarolinaChapel HillNCUSA(Crooks AM)Department of NeurologyUniversity of North CarolinaChapel HillNCUSA

Neurotrophins have been recognized for decades for their beneficial effects on growth,survival,and maintenance in the central nervous system,all of which suggest potential therapeutic utility.Although understanding and harnessing the activity of neurotrophins has proven difficult,the past several years have seen significant strides in the development of deliverable therapies that modulate neurotrophin activity(Shen et al.,2019;Yang et al.,2020;Xie et al.,2021).These recent studies have primarily focused on the multifunctional p75 neurotrophin receptor(p75NTR)which is upregulated in central nervous system disease and injury,thus offering a unique target for intervention.

关键词： al. therapies p75

User scheduling and power allocation for downlink multi-cell multi-carrier NOmA systems

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Digital Communications and Networks 2023年第1期9卷 252-263页

作者： Abuzar b.m.Adam Xiaoyu Wan Zhengqiang Wang School of Communications and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China

In Non-Orthogonal multiple Access(NOmA),the best way to fully exploit the benefits of the system is the efficient resource allocation.For the NOmA power domain,the allocation of power and spectrum require solving the mixed-integer nonlinear programming NP-hard problem.In this paper,we investigate user scheduling and power allocation in multi-Cell multi-Carrier NOmA(mCmC-NOmA)networks.To achieve that,we consider Weighted Sum Rate maximization(WSRm)and Weighted Sum Energy Efficiency maximization(WSEEm)problems.First,we tackle the problem of user scheduling for fixed power using Fractional Programming(FP),the Lagrange dual method,and the decomposition method.Then,we consider Successive Pseudo-Convex Approximation(SPCA)to deal with the WSRm problem.Finally,for the WSEEm problem,SPCA is utilized to convert the problem into separable scalar problems,which can be parallelly solved.Thus,the Dinkelbach algorithm and constraints relaxation are used to characterize the closed-form solution for power allocation.Extensive simulations have been implemented to show the efficiency of the proposed framework and its superiority over other existing schemes.

关键词： Weighted sum rate Weighted energy efficiency Non-orthogonal multiple access Successive pseudo-convex approximation Fractional programming

Nonlinear elastic constitutive relations of residually stressed composites with stiff curved fibres

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Applied mathematics and mechanics(English Edition) 2022年第10期43卷 1515-1530页

作者： m.H.b.m.Shariff J.merodio R.bustamante Department of mathematics Khalifa University of Science and TechnologyAbu Dhabi127788United Arab Emirates Departamento de matemática Aplicada a las TIC ETS de Ingeniería de Sistemas InformaticosUniversidad Politecnica de MadridMadrid28031Spain Departamento de Ingeniería mecánica Universidad de ChileBeauchef 851Santiago CentroSantiago8370448Chile

mechanical models of residually stressed fibre-reinforced solids,which do not resist bending,have been developed in the literature.However,in some residually stressed fibre-reinforced elastic solids,resistance to fibre bending is significant,and the mechanical behavior of such solids should be investigated.Hence,in this paper,we model the mechanical aspect of residually stressed elastic solids with bending stiffness due to fibre curvature,which up to the authors’knowledge has not been mechanically modeled in the past.The proposed constitutive equation involves a nonsymmetric stress and a couple-stress tensor.Spectral invariants are used in the constitutive equation,where each spectral invariant has an intelligible physical meaning,and hence they are useful in experiment and analysis.A prototype strain energy function is proposed.moreover,we use this prototype to give results for some cylindrical boundary value problems.

关键词： fibre-reinforced solid residual stress bending stiffness spectral invariant second gradient finite elasticity

Performance Enhancement of PV based boost Cascaded Fifteen Level Inverter for AC Loads

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Computer Systems Science & Engineering 2022年第7期42卷 165-181页

作者： m.P.Viswanathan b.Anand Department of Electrical and Electronics Engineering Hindusthan College of Engineering and TechnologyCoimbatore641032India

In this research work,single-stageﬁfteen levels cascaded DC-interface converter(CDDCLC)is proposed for sun arranged photovoltaic technology(PV)applications.The proposed geography is joined with help DC chopper and H-associate inverter to upgrade the power converter to accomplish the diminished harmonic proﬁle.In assessment with the customary inverter structures,the proposed system is used with diminished voltage stress,decreased switch count and DC source tally.The proposed research work with cascaded DC link conver-ter design requires three DC sources for combiningﬁfteen-level AC output.This investigation structure switching technique is phase opposition and disposition pulse width modulation technique(POPD)which results in improved quality of obtained output AC power with 6.73%THD and also determinedly recommended for power converters used in UPS and drive applications since it is extremely affordable.A simulation and prototype model ofﬁfteen-level CDDCLC system is deployed and its performance is analyzed for various operating conditions.

关键词： Cascaded DClinkconverter(CDDCLC) modified phaseopposition and disposition(mPOPDPWm) photovoltaic(PV) DCinterfaceboostconverter