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流动人口婚育行为、婚育观念的转变及应对策略

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河北大学学报（哲学社会科学版） 2024年第3期49卷 104-115页

作者：原新丁琪南开大学经济学院天津300071

利用2010—2018年中国流动人口动态监测调查数据,结合2000—2020年历次全国人口普查和人口统计数据,分析中国流动人口婚育行为和婚育观念转变的总体趋势,并探究流动人口婚育观念转变的内在机理。研究发现中国流动人口初婚年龄推迟,婚姻... 详细信息

利用2010—2018年中国流动人口动态监测调查数据,结合2000—2020年历次全国人口普查和人口统计数据,分析中国流动人口婚育行为和婚育观念转变的总体趋势,并探究流动人口婚育观念转变的内在机理。研究发现中国流动人口初婚年龄推迟,婚姻稳定性减弱;初育年龄推迟,生育率水平略有回升;家庭规模缩小,家庭化迁移趋势增强。流动人口婚育观念兼有传统型和现代性的双重特点,城市多元文化交融、社会包容性较高、生活方式转变、经济成本压力、户籍制度壁垒是流动人口婚育观念转变的主要原因。由此提出具体对策建议:深化户籍制度改革,完善流动人口社会保障;完善生育配套支持措施,缓解流动人口经济压力;加强社会意识和教育,塑造新型婚育文化;增加职业技能培训,提高流动人口收入水平。

关键词：流动人口婚育行为婚育观念

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寄生虫抗癌症作用及其机制研究进展

中国血吸虫病防治杂志 2024年第1期36卷 91-97页

作者：张莹舒丁昕戴洋南京医科大学公共卫生学院江苏南京211166 国家卫生健康委员会寄生虫病预防与控制技术重点实验室、江苏省寄生虫与媒介控制技术重点实验室、江苏省医学重点实验室、江苏省血吸虫病防治研究所江苏无锡214064

寄生虫病和癌症均为严重危害人类健康的疾病。近年来研究发现,寄生虫感染与肿瘤间关系密切,多种寄生虫感染及其来源产物能够抑制癌症发生、发展与转移,显示了较好抗癌症潜能。因此,充分解析寄生虫、癌症与宿主间的相互作用,不仅可以为... 详细信息

寄生虫病和癌症均为严重危害人类健康的疾病。近年来研究发现,寄生虫感染与肿瘤间关系密切,多种寄生虫感染及其来源产物能够抑制癌症发生、发展与转移,显示了较好抗癌症潜能。因此,充分解析寄生虫、癌症与宿主间的相互作用,不仅可以为癌症治疗领域研究开拓新的思路,而且可为寄生虫来源抗癌症活性分子筛选奠定基础。本文围绕寄生虫的抗癌症效应及其潜在机制等方面的最新研究进展作一综述。

关键词：寄生虫癌症宿主抗癌作用分子机制

Whittle’s Index Based Sensor Scheduling for Multiprocess Systems Under DoS Attacks

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Journal of Systems Science & Complexity 2024年第1期37卷 329-350页

作者： CAI Zai ding Kemi Shenzhen Key Laboratory of Control Theory and Intelligent Systems Southern University of Science and TechnologyShenzhen 518055China.

In this paper,the authors consider how to design defensive countermeasures against DoS attacks for remote state estimation of multiprocess systems.For each system,a sensor will measure its state and transmits the data packets through an unreliable channel which is vulnerable to be jammed by an attacker.Under limited communication bandwidth,only a subset of sensors are allowed for data transmission,and how to select the optimal one to maximize the accuracy of remote state estimation is the focus of the proposed work.The authors first formulate this problem as a Markov decision process and investigate the existence of optimal policy.Moreover,the authors demonstrate the piecewise monotonicity structure of optimal policy.Given the difficulty of obtaining an optimal policy of large-scale problems,the authors develop a suboptimal heuristic policy based on the aforementioned policy structure and Whittle’s index.Moreover,a closed form of the indices is derived in order to reduce implementation complexity of proposed scheduling policy and numerical examples are provided to illustrate the proposed developed results.

关键词： DoS attacks Kalman filter remote state estimation Whittle’s index.

Constraint on the focal mechanism of the 2011 Tohoku earthquake from the radial modes

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Geodesy and Geodynamics 2024年第1期15卷 27-32页

作者： Weikun Chen Hao ding School of Geodesy and Geomatics Hubei LuoJia LaboratoryWuhan UniversityWuhan 430079China

Different from other normal modes of the Earth’s free oscillation that depend on all the six components(M_(rr),M_(tt),M_(pp),M_(rt),M_(rp),and M_(tp))of the centroid moment tensor,the amplitudes of the radial modes depend on the M_(rr)component(e.g.,scalar moment(M_(0)),dip(δ),and slip(λ))and hypocenter depth of the focal mechanism,and hence can be easily used to constrain these parameters of the focal mechanism.In this study,we use the superconducting gravimeter(SG)records after the 2011 Tohoku earthquake to analyze the radial modes_(0)S_(0)and_(1)S_(0).Based on the solutions of the focal mechanism provided by the GCMT and USGS,we can obtain the theoretical amplitudes of these two radial modes.Comparing the theoretical amplitudes with the observation amplitudes,it is found that there are obvious differences between the former and the latter,which means that the GCMT and USGS focal mechanisms cannot well represent the real focal mechanism of the 2011 event.Taking the GCMT solution as a reference and changing the depth and the three parameters of the M_(rr)moment,the scalar moment(M_(0))and the dip(δ)have significant influences,but the effects of the slip(λ)and the depth are minor.After comparisons,we provide a new constraint(M_(0)=5.8±0.09×10^(22)N·m,δ=10.1±0.08°,λ=88°,and depth=20 km)for the focal mechanism of the 2011 event.In addition,we further determine the center frequency(1.631567±2.6e^(-6)mHz)and quality factor(2046.4±50.1)of the_(1)S_(0)mode.

关键词： Focal mechanism Radial modes Gravity observation

Catalysis by subsurface metal atoms in Al(001) through electron transfer

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National Science Review 2024年第4期11卷 12-13页

作者： Bo Sun ding Ma Beijing National Laboratory for Molecular Science New Cornerstone Science Laboratory College of Chemistry and Molecular Engineering Peking University

Heterogeneous catalysis plays a crucial role in the chemical industry, which has evolved from the investigation of chemisorption to an electronic structure[1]. Diverse strategies, such as alloying,doping, and confining, have been applied to enhance the catalytic properties of active sites through electronic modulation. The electron transfer between active sites and substrates profoundly influences catalytic activity [2].

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A vertical track nonlinear energy sink

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 931-946页

作者： Meng LI Hu ding Shanghai Key Laboratory of Mechanics in Energy Engineering School of Mechanics and Engineering ScienceShanghai Frontier Science Center of MechanoinformaticsShanghai UniversityShanghai 200444China

Eliminating the effects of gravity and designing nonlinear energy sinks(NESs)that suppress vibration in the vertical direction is a challenging task with numerous damping requirements.In this paper,the dynamic design of a vertical track nonlinear energy sink(VTNES)with zero linear stiffness in the vertical direction is proposed and realized for the first time.The motion differential equations of the VTNES coupled with a linear oscillator(LO)are established.With the strong nonlinearity considered of the VTNES,the steady-state response of the system is analyzed with the harmonic balance method(HBM),and the accuracy of the HBM is verified numerically.On this basis,the VTNES prototype is manufactured,and its nonlinear stiffness is identified.The damping effect and dynamic characteristics of the VTNES are studied theoretically and experimentally.The results show that the VTNES has better damping effects when strong modulation responses(SMRs)occur.Moreover,even for small-amplitude vibration,the VTNES also has a good vibration suppression effect.To sum up,in order to suppress the vertical vibration,an NES is designed and developed,which can suppress the vertical vibration within certain ranges of the resonance frequency and the vibration intensity.

关键词： track nonlinear energy sink(TNES) vertical direction gravity nonlinear stiffness harmonic balance method(HBM) vibration control

Deep structure of the Southeast Asian curved subduction system and its dynamic process

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Journal of Oceanology and Limnology 2024年第3期42卷 701-704页

作者： Weiwei ding Key Laboratory of Submarine Geoscience&Second Institute of Oceanography Ministry of Natural ResourcesHangzhou 310012China School of Oceanography Shanghai Jiao Tong UniversityShanghai 200030China

The deep structure,material circulation,and dynamic processes in the Southeast Asia have long been an elusive scientific puzzle due to the lack of systematic scientific observations and recognized theoretical models.Based on the deep seismic tomography using long-period natural earthquake data,in this study,the deep structure and material circulation of the curved subduction system in Southeast Asia was studied,and the dynamic processes since 100 million years ago was reconstructed.It is pointed out that challenges still exist in the precise reconstruction of deep mantle structures of the study area,the influence of multi-stage subduction on deep material exchange and shallow magma activity,as well as the spatiotemporal evolution and coupling mechanism of multi-plate convergence.Future work should focus on high-resolution land-sea joint 3-D seismic tomography imaging of the curved subduction system in the Southeast Asia,combined with geochemical analysis and geodynamic modelling works.

关键词： curved subduction system deep structure material recycling dynamic process Southeast Asia

国家电子商务示范城市建设如何缩小城乡收入差距?——基于全国258个地级市的证据

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软科学 2024年第3期38卷 70-76,84页

作者：张志新丁鑫刘晓合山东理工大学经济学院山东淄博255022

基于国家电子商务示范城市建设的准自然实验,使用2010—2020年258个地级市面板数据和阿里淘宝村数据,构建多期DID、PSM-DID等模型,实证检验了国家电子商务示范城市建设对城乡收入差距的影响。结果表明:示范城市建设对农村和城市人均可... 详细信息

基于国家电子商务示范城市建设的准自然实验,使用2010—2020年258个地级市面板数据和阿里淘宝村数据,构建多期DID、PSM-DID等模型,实证检验了国家电子商务示范城市建设对城乡收入差距的影响。结果表明:示范城市建设对农村和城市人均可支配收入分别提升15.1%和8.7%,有效缩小了城乡收入差距。机制分析发现:示范城市建设通过促进农村电商发展和带动中低技能就业缩小城乡收入差距。异质性分析得出:示范城市缩小城乡收入差距的作用主要体现在中小城市和南方城市,对大城市和北方城市作用效果不明显。鉴于此,建议在加强已有示范城市建设的基础上,增加中小城市试点,实现试点工作下沉到区县;北方城市要借鉴南方城市电商模式,完善农村地区配套设施,打造农村电商特色;组织公益性就业技能培训,提升农户就业水平。

关键词：电子商务示范城市城乡收入差距多期DID

Improving constraint on Ωfrom SDSS using marked correlation functions

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Science China(Physics,Mechanics & Astronomy) 2024年

作者： Limin Lai Jiacheng ding Xiaolin Luo Yizhao Yang Zihan Wang Keshi Liu Guanfu Liu xin Wang Yi Zheng Zhaoyu Li Le Zhang Xiaodong Li School of Physics and Astronomy Sun Yat-sen University Zhuhai Campus Department of Astronomy Shanghai Jiao Tong University Department of Astronomy Tsinghua University CSST Science Center for the Guangdong-Hong Kong-Macao Greater Bay Area SYSU Peng Cheng Laboratory

Large-scale structure （LSS） surveys will increasingly provide stringent constraints on our cosmological models.Recently,the density-marked correlation function （MCF） has been introduced,offering an easily computable density-correlation statistic.Simulations have demonstrated that MCFs offer additional,independent constraints on cosmological models beyond the standard two-point correlation （2PCF）.In this study,we apply MCFs for the first time to SDSS CMASS data,aiming to investigate the statistical information regarding clustering and anisotropy properties in the Universe and assess the performance of various weighting schemes in MCFs,and finally obtain constraints on Ωm.Upon analyzing the CMASS data,we observe that,by combining different weights （α=[-0.2,0,0.2,0.6]）,the MCFs provide a tight and independent constraint on the cosmological parameter Ωm,yielding Ωm=0.293±0.006 at the 1σlevel,which represents a significant reduction in the statistical error by a factor of 3.4compared to that from 2PCF.Our constraint is consistent with recent findings from the small-scale clustering of BOSS galaxies(Zhai et al.Astronphys.J.948,99 （2023）) within the 1σlevel.However,we also find that our estimate is lower than the Planck measurements by about 2.6σ,indicating the potential presence of new physics beyond the standard cosmological model if all the systematics are fully corrected.The method outlined in this study can be extended to other surveys and datasets,allowing for the constraint of other cosmological parameters.Additionally,it serves as a valuable tool for forthcoming emulator analysis on the Chinese Space Station Telescope （CSST）.

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