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Projection-based Consistent Test for Linear Regression Model with Missing Response and Covariates

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Acta Mathematicae Applicatae Sinica 2020年第4期36卷 917-935页

作者： Su-jin ZHENG Si-yu GAO zhi-hua sun China Institute for Actuarial Science/School of Insurance Central University of Finance and EconomicsBeijing 100081China School of Mat hematic Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Big Data Mining and Knowledge Management of Chinese Academy of Sciences Beijing 100049China

In recent years,there has been a large amount of literature on missing *** of them focus on situations where there is only missingness in response or *** this paper,we consider the adequacy check for the linear regression model with the response and covariates missing *** apply model adjustment and inverse probability weighting methods to deal with the missingness of response and covariate,*** order to avoid the curse of dimension,we propose an empirical process test with the linear indicator weighting *** asymptotic properties of the proposed test under the null,local and global alternative hypothe tical models are rigorously investigated.A consisten t wild boot strap method is developed to approximate the critical ***,simulation studies and real data analysis are performed to show that the proposed method performed well.

关键词： consistency linear indicator weighting function empirical process missing response and covariates projection

Variable Selection of Generalized Regression Models Based on Maximum Rank Correlation

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Acta Mathematicae Applicatae Sinica 2014年第3期30卷 833-844页

作者： Peng-jie DAI Qing-zhao ZHANG zhi-hua sun School of Business Renmin University of China Department of Mathematics University of Chinese Academy of Sciences

In this paper, we investigate the variable selection problem of the generalized regression models. To estimate the regression parameter, a procedure combining the rank correlation method and the adaptive lasso technique is developed, which is proved to have oracle properties. A modified IMO （iterative marginal optimization） algorithm which directly aims to maximize the penalized rank correlation function is proposed. The effects of the estimating procedure are illustrated by simulation studies.

关键词： maximum rank correlation estimation adaptive LASSO oracle properties generalized regression models.

Semiparametric Analysis of Longitudinal Data with Informative Observation Times

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Acta Mathematicae Applicatae Sinica 2011年第1期27卷 29-42页

作者： Liu-quan sun Xiao-yun Mu zhi-hua sun Xing-wei Tong Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China School of mathematical Sciences Beijing Normal University Beijing 100875 China

In many longitudinal studies, observation times as well as censoring times may be correlated with longitudinal responses. This paper considers a multiplicative random effects model for the longitudinal response where these correlations may exist and a joint modeling approach is proposed via a shared latent variable. For inference about regression parameters, estimating equation approaches are developed and asymptotic properties of the proposed estimators are established. The finite sample behavior of the methods is examined through simulation studies and an application to a data set from a bladder cancer study is provided for illustration.

关键词： Estimating equations Informative observation times Joint modeling Latent variables,Longitudinal data

A new sesquiterpene from Caragana intermediia

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Chinese Chemical Letters 2007年第11期18卷 1379-1382页

作者： zhi hua sun Chang Qi Hu Jin Yi Wang School of Pharmacy Fudan University Shanghai 200032 China College of Science Northwest A＆F University Yangling 712100 China

A new alloaromadendrane-type sesquiterpene, （-）-alloaromadendrane-3β,9β-diol （1）, has been isolated from the aerial part of Caragana intermediia. The structure of （-）-alloaromadendrane-3β,9β-diol （1） was established by spectroscopic methods, including X-ray analysis that provided its relative stereochemistry. Bioassay showed that （-）-alloaromadendrane-3β,9β-diol （1） possesses anti-pyricularia oryzae P-2b activity with MIC value of 10 μg/m-L.

关键词： Caragana intermediia Leguminosae Sesquitetpene (-)-Alloaromadendrane-3β,9β-diol

Quasi-likelihood estimation of average treatment effects based on model information

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Science China Mathematics 2007年第1期50卷 1-12页

作者： zhi-hua sun Academy of Mathematics and Systems Science, Chinese Academy of Science, Beijing 100080, China Academy of Mathematics and Systems Science Chinese Academy of Science Beijing China

In this paper, the estimation of average treatment effects is considered when we have the model information of the conditional mean and conditional variance for the responses given the covariates. The quasi-likelihood method adapted to treatment effects data is developed to estimate the parameters in the conditional mean and conditional variance models. Based on the model information, we define three estimators by imputation, regression and inverse probability weighted methods. All the estimators are shown asymptotically normal. Our simulation results show that by using the model information, the substantial efficiency gains are obtained which are comparable with the existing estimators.

关键词： average treatment effects inverse probability weighted quasi-likelihood unconfounded assignment treatment model information 62G18

Investigation on Third-Order Optical Nonlinearities of Two Organometallic Dmit2- Complexes Using Z-Scan Technique

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Natural Science 2009年第2期1卷 136-141页

作者： He-Liang Fan Quan Ren Xin-Qiang Wang Ting-Bin Li Jing sun Guang-Hui Zhang Dong Xu Gang Yu zhi-hua sun 不详

The third-order nonlinear optical properties of two dmit organometallic complexes, [(CH3)4N] [Au(C3S5)2] (MeAu) and [(CH3)4N][Ni(C3S5)2] (Me Ni) in acetone solutions, were characterized us- ing a short pulse Z-scan technique at 1064 nm wavelength. Self-defocusing effects were found in both samples and stronger saturable absorp-tion was observed in MeNi solution comparing with that of MeAu. The origins were analyzed for the differences between the results. Two figures of merit W and T were also calculated to evalu-ate the suitability of two materials for all-optical integrated devices. The results of W=22.84 and T≈0 of MeAu make it an excellent candidate for the all-optical applications.

关键词： Z-scan Technique Third-order Nonlinearity Metal-dmit Complexes Figure of Merit.

Preparation of graphene and TiO2 layer by layer composite with highly photocatalytic efficiency

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Progress in Natural Science:Materials International 2011年第6期21卷 467-471页

作者： Yu-peng ZHANG~1,Jun-jie XU~1,zhi-hua sun~1,Chen-zhe LI~1,Chun-xu PAN~(1,2) 1.Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education, School of Physics and Technology,Wuhan University,Wuhan 430072,China 2.Center for Electron Microscopy,Wuhan University,Wuhan 430072,China Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education School of Physics and Technology Wuhan University Wuhan 430072 China Center for Electron Microscopy Wuhan University Wuhan 430072 China

A process for fabricating graphene and TiO2layer by layer composite was introduced to improve the photocatalytic activity by controlling the layers,thickness and the mass ratio between graphene and *** graphene oxide（GO） was synthesized from natural graphite powder by the modified Hummers ***-area uniform GO and TiO2thin films were made by a spin-coating process in *** exposure of the TiO2/GO multilayer film to UV light irradiation which allows the reduction of GO to graphene,a novel photocatalytic structure as graphene and TiO2layer by layer composite was *** cross-sectional SEM image showed that a clear layer by layer microstructure with a single layer thickness of graphene or TiO2was in the range of about 50 *** total thickness of the film was around 5μm which was varied according to the layer number of spin coating *** spectra revealed that significant structural changes occurred through UV light *** for methylene blue（MB） exhibited that the layer by layer composite is of higher photocatalytic activity than the pure TiO2layer.

关键词： graphene TiO2 photocatalysis layer by layer composite

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河北省服务业竞争力实证研究

特区经济 2011年第7期 74-76页

作者：赖志花孙晓彤王必锋石家庄经济学院河北石家庄050031 石家庄铁路职业技术学院河北石家庄050041

本论文从产业竞争实力、产业竞争潜力、产业竞争能力和环境四方面构建服务业竞争力指标体系,采用因子分析方法分析河北省服务业竞争力影响因素,并在此基础上提出相对应的对策与建议。

关键词：服务业河北省产业竞争力

Low‑Temperature Oxidation Induced Phase Evolution with Gradient Magnetic Heterointerfaces for Superior Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 191-204页

作者： Zizhuang He Lingzi Shi Ran sun Lianfei Ding Mukun He Jiaming Li hua Guo Tiande Gao Panbo Liu School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710129People’s Republic of China School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072People’s Republic of China

Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significant challenging in regulating local phase ***,accordion-shaped Co/Co_(3)O_(4)@N-doped carbon nanosheets(Co/Co_(3)O_(4)@NC)with gradient magnetic heterointerfaces have been fabricated via the cooperative high-temperature carbonization and lowtemperature oxidation *** results indicate that the surface epitaxial growth of crystal Co_(3)O_(4) domains on local Co nanoparticles realizes the adjustment of magnetic-heteroatomic components,which are beneficial for optimizing impedance matching and interfacial ***,gradient magnetic heterointerfaces simultaneously realize magnetic coupling,and long-range magnetic ***,the synthesized Co/Co_(3)O_(4)@NC absorbents display the strong electromagnetic wave attenuation capability of−53.5 dB at a thickness of 3.0 mm with an effective absorption bandwidth of 5.36 GHz,both are superior to those of single magnetic domains embedded in carbon *** design concept provides us an inspiration in optimizing interfacial polarization,regulating magnetic coupling and promoting electromagnetic wave absorption.

关键词： Magnetic heterointerfaces Phase evolution Interfacial polarization Magnetic coupling Electromagnetic wave absorption