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The Proportional Mean Residual Life Regression Model with Cure Fraction and Auxiliary Covariate

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Acta Mathematicae Applicatae Sinica 2022年第2期38卷 312-323页

作者： shao-jia JIN yan-yan LIU Guang-cai MAO ming-yu SHAN School of Mathematics and Statistics Wuhan UniversityWuhan 430072China School of Mathematics and Statistics Central China Normal UniversityWuhan 430079China

As biological studies become more expensive to conduct,it is a frequently encountered question that how to take advantage of the available auxiliary covariate information when the exposure variable is not *** this paper,we propose an induced cure rate mean residual life time regression model to accommodate the survival data with cure fraction and auxiliary covariate,in which the exposure variable is only assessed in a validation set,but a corresponding continuous auxiliary covariate is ascertained for all subjects in the study *** studies elucidate the practical performance of the proposed method under finite *** an illustration,we apply the proposed method to a heart disease data from the Study of Left Ventricular Dysfunction.

关键词： auxiliary covariate Kernel smoothing logistic regression mean residual life mixture cure model

Impact Analysis of Solar Irradiance Change on Precision Orbit Determination of Navigation Satellites

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第6期36卷 889-901页

作者： ZHANG yan WANG Xiaoya XI Kewei shao Fan Astro-Geodynamics Research Center Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China Shanghai Key Laboratory of Space Navigation and Positioning Techniques Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030P.R.China

Solar radiation pressure is the main driving force and error source for precision orbit determination of navigation *** is proportional to the solar irradiance,which is the"sun constant".In regular calculation,the"solar constant"is regard as a ***,due to the existence of sunspots,flares,etc.,the solar constant is not fixed,the change in the year is about 1%.To investigate the variation of solar irradiance,we use interpolation and average segment modeling of total solar irradiance data of SORCE,establishing variance solar radiation pressure(VARSRP)model and average solar radiation pressure(AVESRP)model based on the built solar pressure model(SRPM)(constant model).According to observation data of global positioning system(GPS)and Beidou system(BDS)in 2015 and comparing the solar pressure acceleration of VARSRP,AVESRP and SRPM,the magnitude of change can reach 10-10 m/s^*** addition,according to the satellite precise orbit determination,for GPS satellites,the results of VARSRP and AVESRP are slightly smaller than those of the SRPM model,and the improvement is between 0.1 to 0.5 *** geosynchronous orbit(GEO)satellites of BDS,The AVESRP and VARSRP have an improvement of 3.5 mm and 4.0 mm,respectively,based on overlapping arc,and SLR check results show the AVESRP model and the VARSRP model is improved by 2.3 mm and 3.5 mm,***,the change of inclined geosynchronous orbit(IGSO)satellites and medium earth orbit(MEO)satellites is relatively small,and the improvement is smaller than 0.5 mm.

关键词： solar pressure acceleration total solar irradiance precise orbit determination global positioning system(GPS) Beidou system(BDS)

Modeling ε Eri and Asteroseismic Tests of Element Diffusion

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Chinese Journal of Astronomy and Astrophysics 2008年第5期8卷 591-602页

作者： Ning Gai shao-Lan Bi yan-Ke Tang National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China Department of Astronomy Beijing Normal University Beijing 100875 China Graduate School of Chinese Academy of Sciences Beijing 100049 China

Taking into account the helium and metal diffusion, we explore the possible evolutionary status with a seismic analysis, of the MOST （Microvariability and Oscillations of STars） target： the star e Eri. We adopt different input parameters to construct models to fit the available observational constraints in, e.g., Teff, L, R and [Fe/H]. From the computation we obtain the average large spacings of e Eri to be about 194 ± 1μHz. The age of the diffused models was found to be about 1 Gyr, which is younger than the age determined previously by models without diffusion. We found that the effect of pure helium diffusion on the internal structure of the young low-mass star is slight, but that of metal diffusion is obvious. The metal diffusion leads the models to have much higher temperature in the radiative interior, and, correspondingly a higher sound speed there, hence a larger frequency and spacings.

关键词： stars evolution - stars interiors -stars individual ∈ Eridani

SN 1054: A pulsar-powered supernova?

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Research in Astronomy and Astrophysics 2015年第11期15卷 1823-1831页

作者： shao-Ze Li Yun-Wei Yu yan Huang Institute of Astrophysics Central China Normal University

The famous ancient supernova SN 1054 could have been too bright to be explained in the “standard” radioactive-powered supernova scenario. As an alternative attempt, we demonstrate that the spin-down of the newly born Crab pulsar could provide a sufficient energy supply to make SN 1054 visible at daytime for 23 days and at night for 653 days, where a one-zone semi-analytical model is employed. Our results indicate that SN 1054 could be a “normal” cousin of magnetar-powered superluminous supernovae. Therefore, SN 1054-like supernovae could be a probe to uncover the properties of newly born neutron stars, which provide initial conditions for studies on neutron star evolutions.

关键词： scenario powered neutron gamma bright ancient luminosity attempt radioactive stars

Atmospheric-pressure pulsed discharges and plasmas:mechanism,characteristics and applications

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High Voltage 2018年第1期3卷 14-20页

作者： Tao shao Ruixue Wang Cheng Zhang Ping yan Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190People's Republic of China Key Laboratory of Power Electronics and Electric Drive Chinese Academy of SciencesBeijing 100190People's Republic of China

Pulsed discharge plasma and its application is one of the promising directions in civilian areas of pulsed power *** order to promote the research and development of the theory and application technology for pulsed discharge plasma,in this paper,recent progress on the mechanism of nanosecond-pulse gas discharge and the characteristics and applications of typical pulsed plasma at the Institute of Electrical Engineering,Chinese Academy of Sciences is ***,progress on mechanism of nanosecond-pulse discharge based on runaway electrons and measurement technology of runaway electrons is ***,the characteristics of three typical discharges,including direct-driven pulsed discharge,pulsed dielectric barrier discharge and pulsed plasma jet,are ***,typical plasma applications of pulsed plasma on surface modification and methane conversion are presented.

关键词： mechanism pulsed directions

Accessibility and Homology Bounded Strong Unstable Foliation for Anosov Diffeomorphisms on 3-torus

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Acta Mathematica Sinica,English Series 2017年第1期33卷 71-76页

作者： yan REN shao Bo GAN Peng Fei ZHANG School of Mathematical Sciences Peking University Department of Mathematics and Statistics Universityof Massachusetts

We give three equivalent conditions for non-accessibility of an Anosov diffeomorphism on the 3-torus with a partially hyperbolic splitting. Since accessibility is an open property, this gives a negative answer to Hammerlindl＇s question about homology boundedness of strong unstable foliation. Keywords Partially hyperbolic, accessible, homology bounded

关键词： Partially hyperbolic accessible homology bounded

Formation mechanism and control methods of acicular ferrite in HSLA steels:A review

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Journal of Materials Science & Technology 2018年第5期34卷 737-744页

作者： Yi shao Chenxi Liu Zesheng yan Huijun Li Yongchang Liu State Key Lab of Hydraulic Engineering Simulation and Safety School of Materials Science and EngineeringTianjin University

High strength low alloy（HSLA） steels have been widely used in pipelines,power plant components,civil structures and so on,due to their outstanding mechanical properties as high strength and toughness,and excellent ***-phase microstructures containing acicular ferrite or acicular ferrite dominated phase have been proved to possess good comprehensive properties in HSLA *** paper mainly focuses on the formation mechanisms and control methods of acicular ferrite in HSLA *** of austenitizing conditions,continuous cooling rate,and isothermal quenching time and temperature on acicular ferrite transformation was ***,the modified process to control the formation of multi-phase microstructures containing acicular ferrite,as intercritical heat treatments,step quenching treatments and thermo-mechanical controlled processing,was *** favorable combination of mechanical properties can be achieved by these modified treatments.

关键词： HSLA steels Acicular ferrite Microstructure Mechanical properties Intercritical heat treatment Step quenching Thermo-mechanical controlled processing

Electronic shell study of prolate Lin(n=15–17)clusters:Magnetic superatomic molecules

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Chinese Physics B 2020年第12期29卷 361-366页

作者： Lijuan yan Jianmei shao Yongqiang Li College of Electronics&Information Engineering Guangdong Ocean UniversityZhanjiang 524088China

The non-spherical lowest-lying Lin(n=15–17)isomers were found with high symmetric compact structures,of which the stability was not rationalized in a previous report(***.1199444(2003)).Based on the newly proposed super-valence bond model,the three prolate lithium clusters can be viewed as magnetic superatomic molecules,which are composed by sharing valence electron pairs and nuclei between two superatom units,namely,Li10 or Li11,and thus their stability can be given a good *** orbital and chemical bonding analysis clearly reveal that the Lin(n=15–17)clusters with prolate shapes are magnetic superatomic *** work may aid in the developments of the cluster-assembled materials or superatom-bonds.

关键词： jellium model geometry and electronic shells magnetic properties stability electron delocalization

Unconventional superfluidity of superconductivity on Penrose lattice

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Science China(Physics,Mechanics & Astronomy) 2023年第9期66卷 8-14页

作者： Yu-Bo Liu Zhi-yan shao Ye Cao Fan yang School of Physics Beijing Institute of TechnologyBeijing 100081China

Using the attractive Hubbard model as an example,we theoretically investigate the gap function,superfluid density,and superconductivity(SC)transition temperature on the semiperiodic Penrose ***,we clarify that the gap function,density of states,and superfluid density positively correlate to the extended degree of single-particle states around the Fermi ***,we confirm that the paramagnetic component of the superfluid density does not decay to zero in the thermodynamic limit,which is completely diferent from periodic *** of the scaling,the diference between diamagnetic and paramagnetic currents remains stable,consistent with recent experimental results showing that although the superfluid density is lower than that of a periodic system,the system has bulk ***,we find that the superfluid density and SC transition temperature can be boosted with the increase in disorder strength,which should be general to quasicrystal but unusual to periodic systems,reflecting the interplay between the underlying geometry and disorder.

关键词： quasicrystals superfluid density extended degree