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土体抗剪强度各向异性对边坡滑动模式与稳定性的影响

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江苏大学学报（自然科学版） 2025年第1期46卷 91-97页

作者：张飞胡光华河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210024 河海大学江苏省岩土工程技术工程研究中心江苏南京210024

基于极限分析法中的上限定理,开展了考虑土体抗剪强度各向异性的边坡稳定性研究,通过参数分析研究了土体抗剪强度各向异性对边坡失稳滑动方式与边坡稳定性安全系数的影响规律.结果表明:边坡稳定性安全系数随着抗剪强度各向异性系数减小... 详细信息

基于极限分析法中的上限定理,开展了考虑土体抗剪强度各向异性的边坡稳定性研究,通过参数分析研究了土体抗剪强度各向异性对边坡失稳滑动方式与边坡稳定性安全系数的影响规律.结果表明:边坡稳定性安全系数随着抗剪强度各向异性系数减小而减小,其影响程度随着土体内摩擦角和坡度的减小而增大;对于土体黏聚力较大、内摩擦角较小的缓坡,随着抗剪强度各向异性系数减小,边坡的最危险滑动面会由坡脚深层破坏转变为坡底深层破坏,滑动范围显著增大;基于计算结果绘制了稳定图(stability chart),实现了考虑土体抗剪强度各向异性影响的边坡稳定性安全系数的快速计算与最危险滑动方式的判别.

关键词：边坡抗剪强度各向异性稳定性安全系数极限分析法滑动

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智能机器人在基层慢性病管理中的应用与挑战

中国全科医学 2025年第1期28卷 7-12,19页

作者：张璇张飞李铭麟王佳贺中国医科大学附属盛京医院全科医学科辽宁省沈阳市110000

全球慢性病患病率不断上升,给社会的发展和个人健康带来重大挑战。管理慢性病需要长期治疗和监测,对患者的生活方式提出了一定要求。随着人口老龄化和人们生活方式的改变,慢性病防控正变得越发重要。近年来,随着医疗卫生领域科技创新向... 详细信息

全球慢性病患病率不断上升,给社会的发展和个人健康带来重大挑战。管理慢性病需要长期治疗和监测,对患者的生活方式提出了一定要求。随着人口老龄化和人们生活方式的改变,慢性病防控正变得越发重要。近年来,随着医疗卫生领域科技创新向纵深发展,借助人工智能的智能机器人在医疗领域的应用也逐渐成为国家重要战略方向之一,传统的慢性病管理方法过于依赖医生和患者之间的线下交流,导致医生无法与患者保持长期且有效的沟通和随访,患者病情出现变化时医生可能无法及时发现和监测。此外,传统的慢性病管理方法通常是一种通用化的方法,无法充分考量到每位患者的个体差异。鉴于传统慢性病管理方法的局限性,本文提倡利用智能机器人提供更便捷高效的基层服务。本文认为,通过个性化健康管理方案、辅助医疗诊断、定时提醒服药等功能,使智能机器人能够致力于改善患者生活质量、减轻医疗资源压力,从而推动全球智能化医疗管理的发展。

关键词：智能机器人初级保健慢性病健康管理人工智能健康大数据

Self-assembly of perovskite nanocrystals:From driving forces to applications

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Journal of Energy Chemistry 2024年第1期88卷 561-578,I0013页

作者： Yi Li fei zhang School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China

Self-assembly of metal halide perovskite nanocrystals(NCs)into superlattices can exhibit unique collective properties,which have significant application values in the display,detector,and solar cell *** review discusses the driving forces behind the self-assembly process of perovskite NCs,and the commonly used self-assembly methods and different self-assembly structures are ***,we summarize the collective optoelectronic properties and application areas of perovskite superlattice ***,we conclude with an outlook on the potential issues and future challenges in developing perovskite NCs.

关键词： Self-assembly Metal halide perovskite Nanocrystals Driving forces

考虑场地效应的多点地震动作用下边坡永久位移分析

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岩土工程学报 2025年第1期47卷 65-75页

作者：宋健潘驭航陆朱汐姬建张飞高玉峰河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210024 河海大学土木与交通学院江苏南京210024

地震动引起的边坡土层非线性动力响应可能导致坡体不同位置的地震动加速度时程不一致,从而对整个滑动体的极限平衡状态及之后的地震累积永久位移产生影响。为了研究场地效应对边坡地震永久位移的影响,基于极限平衡条分法,通过对不同土... 详细信息

地震动引起的边坡土层非线性动力响应可能导致坡体不同位置的地震动加速度时程不一致,从而对整个滑动体的极限平衡状态及之后的地震累积永久位移产生影响。为了研究场地效应对边坡地震永久位移的影响,基于极限平衡条分法,通过对不同土条赋予不同的水平和竖向地震动时程,推导出一种考虑场地效应的圆弧和任意形状滑面的多点地震作用下边坡永久位移分析方法。通过与有限差分软件FLAC的数值模拟结果进行对比,验证了该方法能够合理考虑地震动的场地效应。通过研究不同分布形式的多点地震动及竖向地震动对边坡永久位移的影响,结果表明:场地效应引起的水平地震动放大以及多点地震动不同分布模式会导致整个滑体平均地震惯性力作用位置发生改变,从而影响地震作用下滑动体沿滑面的永久变形量,竖向地震动对边坡地震位移影响较小。将方法应用于Lexington土石坝震后变形案例分析,计算得到的坝坡地震永久位移与实际震后观测值相吻合,证明了考虑场地效应的重要性及本文方法的合理性。

关键词：地震边坡稳定性场地效应永久位移极限平衡条分法多点地震动

Forecast for weighing neutrinos in cosmology with SKA

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Science China(Physics,Mechanics & Astronomy) 2020年第8期63卷 53-60页

作者： Jing-fei zhang Bo Wang Xin zhang Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Ministry of Education’s Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern UniversityShenyang 110819China Center for High Energy Physics Peking UniversityBeijing 100080China

We investigate what role the SKA neutral hydrogen(HI)intensity mapping(IM)and galaxy sky surveys will play in weighing neutrinos in *** use the simulated data of the baryon acoustic oscillation(BAO)measurements from the HI surveys based on SKA1(IM)and SKA2(galaxy)to do the *** the current observations,we use the Planck 2015 cosmic microwave background(CMB)anisotropies observation,the optical BAO measurements,the type Ia supernovae(SN)observation(Pantheon compilation),and the latest H0 *** consider three mass ordering cases for massive neutrinos,i.e.,the normal hierarchy(NH),inverted hierarchy(IH),and degenerate hierarchy(DH)*** is found that the SKA observation can significantly improve the constraints on?m and *** to the current observation,the SKA1 data can improve the constraints on?m by about 33%,and on H0 by about 36%;the SKA2 data can improve the constraints on?m by about 58%,and on H0 by about 66%.It is also found that the SKA observation can only slightly improve the constraints on∑mν.Compared to the current observation,the SKA1 data can improve the constraints on∑mνby about 4%,3%,and 10%,for the NH,IH,and DH cases,respectively;the SKA2 data can improve the constraints on∑mνby about 7%,7%,and 16%,for the NH,IH,and DH cases,respectively.

关键词： 21 cm observation intensity mapping survey Square Kilometre Array baryon acoustic oscillations neutrino mass

Global Well-posedness for gKdV-3 in Sobolev Spaces of Negative Index

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Acta Mathematica Sinica,English Series 2008年第5期24卷 857-866页

作者： Zhi fei zhang School of Mathematical Science Peking University Beijing 100871 P. R. China

The initial value problem for the generalized Korteweg-deVries equation of order three on the line is shown to be globally well posed for rough data. Our proof is based on the multilinear estimate and the I-method int... 详细信息

关键词： KdV equation Global well posedness I-method Multilinear estimate

Searching for sterile neutrinos in dynamical dark energy cosmologies

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Science China(Physics,Mechanics & Astronomy) 2018年第5期61卷 10-19页

作者： Lu Feng Jing-fei zhang Xin zhang Department of Physics College of Sciences Northeastern University Center for High Energy Physics Peking University

We investigate how the dark energy properties change the cosmological limits on sterile neutrino parameters by using recent cosmological observations. We consider the simplest dynamical dark energy models, the wCDM model and the holographic dark energy（HDE） model, to make an analysis. The cosmological observations used in this work include the Planck 2015 CMB temperature and polarization data, the baryon acoustic oscillation data, the type Ia supernova data, the Hubble constant direct measurement data, and the Planck CMB lensing data. We find that, mν,sterileff〈 0.2675 eV and Neff〈 3.5718 for ΛCDM cosmology, mν,sterileff〈 0.5313 eV and Neff〈 3.5008 for wCDM cosmology, and mν,sterileff〈 0.1989 eV and Neff〈 3.6701 for HDE cosmology, from the constraints of the combination of these data. Thus, without the addition of measurements of growth of structure, only upper limits on both mν,sterileff and Neff can be derived, indicating that no evidence of the existence of a sterile neutrino species with e V-scale mass is found in this analysis. Moreover, compared to the ΛCDM model, in the wCDM model the limit on mν,sterileff becomes much looser, but in the HDE model the limit becomes much tighter. Therefore, the dark energy properties could significantly influence the constraint limits of sterile neutrino parameters.

关键词： sterile neutrino dynamical dark energy cosmological observations

Elliptical encirclement control capable of reinforcing performances for UAVs around a dynamic target

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Defence Technology（防务技术） 2024年第2期32卷 104-119页

作者： fei zhang Xingling Shao Yi Xia Wendong zhang National Key Laboratory for Electronic Measurement Technology School of Instrument and ElectronicsNorth University of ChinaTaiyuan030051China

Most researches associated with target encircling control are focused on moving along a circular orbit under an ideal environment free from external ***,elliptical encirclement with a time-varying observation radius,may permit a more flexible and high-efficacy enclosing solution,whilst the non-orthogonal property between axial and tangential speed components,non-ignorable environmental perturbations,and strict assignment requirements empower elliptical encircling control to be more challenging,and the relevant investigations are still *** this line,an appointed-time elliptical encircling control rule capable of reinforcing circumnavigation performances is developed to enable Unmanned Aerial Vehicles(UAVs)to move along a specified elliptical path within a predetermined reaching *** remarkable merits of the designed strategy are that the relative distance controlling error can be guaranteed to evolve within specified regions with a designer-specified convergence ***,wind perturbations can be online counteracted based on an unknown system dynamics estimator(USDE)with only one regulating parameter and high computational *** tool demonstrates that all involved error variables are ultimately limited,and simulations are implemented to confirm the usability of the suggested control algorithm.

关键词： Elliptical encirclement Reinforced performances Wind perturbations UAVs

Impacts of dark energy on constraining neutrino mass after Planck 2018

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Communications in Theoretical Physics 2020年第12期72卷 163-170页

作者： Ming zhang Jing-fei zhang Xin zhang Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Key Laboratory of Data Analytics and Optimization for Smart Industry(Northeastern University) Ministry of EducationShenyang 110819China Center for Gravitation and Cosmology Yangzhou UniversityYangzhou 225009China

Considering the mass splittings of three active neutrinos,we investigate how the properties of dark energy affect the cosmological constraints on the total neutrino mass∑mv using the latest cosmological *** this paper,several typical dark energy models,including ACDM,wCDM,CPL,and HDE models,are *** the analysis,we also consider the effects from the neutrino mass hierarchies,*** degenerate hierarchy(DH),the normal hierarchy(NH),and the inverted hierarchy(IH).We employ the current cosmological observations to do the analysis,including the Planck 2018 temperature and polarization power spectra,the baryon acoustic oscillations(BAO),the type Ia supernovae(SNe),and the Hubble constant H0 *** the ACDM+∑mv model,we obtain the upper limits of the neutrino mass∑mv<0.123 eV(DH),∑mv<0.156 eV(NH),and∑mv<0.185 eV(IH)at the 95%C.L.,using the Planck+BAO+SNe data *** the wCDM+∑mv model and the CPL+∑mv model,larger upper limits of∑mv are obtained compared to those of the ACDM+∑mv *** most stringent constraint on the neutrino mass,∑mv<0.080 eV(DH),is derived in the HDE+∑mv *** addition,we find that the inclusion of the local measurement of the Hubble constant in the data combination leads to tighter constraints on the total neutrino mass in all these dark energy models.

关键词： neutrino mass mass hierarchies of neutrinos dark energy cosmological constraints Planck 2018