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Generalized Empirical likelihood Inference in Semiparametric Regression Model for Longitudinal Data

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Acta Mathematica Sinica,English Series 2008年第12期24卷 2029-2040页

作者： gao rong li Ping TIAN liu Gen XUE College of Applied Sciences Beijing University of Technology Beijing 100022 P. R. China School of Finance and Statistics East China Normal University Shanghai 200241 P. R. China Department of Mathematics Xuchang University Xuchang 461000 P. R. China

In this paper, we consider the semiparametric regression model for longitudinal data. Due to the correlation within groups, a generalized empirical log-likelihood ratio statistic for the unknown parameters in the model is suggested by introducing the working covariance matrix. It is proved that the proposed statistic is asymptotically standard chi-squared under some suitable conditions, and hence it can be used to construct the confidence regions of the parameters. A simulation study is conducted to compare the proposed method with the generalized least squares method in terms of coverage accuracy and average lengths of the confidence intervals.

关键词： longitudinal data semiparametric regression model empirical likelihood confidence region

Efficient Statistical Inference for Partially Nonlinear Errors-in-Variables Models

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Acta Mathematica Sinica,English Series 2014年第9期30卷 1606-1620页

作者： San Ying FENG gao rong li Jun Hua ZHANG College of Applied Sciences Beijing University of Technology College of Mechanical Engineering Beijing Information Science and Technology University

In this paper, we consider the partially nonlinear errors-in-variables models when the non- parametric component is measured with additive error. The profile nonlinear least squares estimator of unknown parameter and the estimator of nonparametric component are constructed, and their asymptotic properties are derived under general assumptions. Finite sample performances of the proposed statistical inference procedures are illustrated by Monte Carlo simulation studies.

关键词： Partially nonlinear errors-in-variables model measurement error ordinary smooth profile nonlinear least squares asymptotic property

Variable Selection for Fixed Effects Varying Coefficient Models

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Acta Mathematica Sinica,English Series 2015年第1期31卷 91-110页

作者： gao rong li Heng liAN Peng LAI Heng PENG Beijing Center for Scientific and Engineering Computing College of Applied SciencesBeijing University of Technology School of Mathematics and Statistics The University of New South Wales School of Mathematics & Statistics Nanjing University of Information Science & Technology Department of Mathematics Hong Kong Baptist University

We consider the problem of variable selection for the fixed effects varying coefficient models. A variable selection procedure is developed using basis function approximations and group nonconcave penalized functions, and the fixed effects are removed using the proper weight matrices. The proposed procedure simultaneously removes the fixed individual effects, selects the significant variables and estimates the nonzero coefficient functions. With appropriate selection of the tuning parameters, an asymptotic theory for the resulting estimates is established under suitable conditions. Simulation studies are carried out to assess the performance of our proposed method, and a real data set is analyzed for further illustration.

关键词： Varying coefficient model fixed effect variable selection basis function

Symmetrical Independence Tests for Two Random Vectors with Arbitrary Dimensional Graphs

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Acta Mathematica Sinica,English Series 2022年第4期38卷 662-682页

作者： Jia Min liU gao rong li Jian Qiang ZHANG Wang li XU Center for Applied Statistics Renmin University of ChinaBeijing 100872P.R.China School of Statistics Beijing Normal UniversityBeijing 100875P.R.China

Test of independence between random vectors X and Y is an essential task in statistical *** type of testing methods is based on the minimal spanning tree of variables X and *** main idea is to generate the minimal spanning tree for one random vector X,and for each edges in minimal spanning tree,the corresponding rank number can be calculated based on another random vector *** resulting test statistics are constructed by these rank ***,the existed statistics are not symmetrical tests about the random vectors X and Y such that the power performance from minimal spanning tree of X is not the same as that from minimal spanning tree of *** addition,the conclusion from minimal spanning tree of X might conflict with that from minimal spanning tree of *** order to solve these problems,we propose several symmetrical independence tests for X and *** exact distributions of test statistics are investigated when the sample size is ***,we study the asymptotic properties of the statistics.A permutation method is introduced for getting critical values of the *** with the existing methods,our proposed methods are more efficient demonstrated by numerical analysis.

关键词： Exact distribution minimal spanning tree asymptotic distribution symmetrical independence test

A Tibetan Countryside Doctor—Lhamo

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Women of China 1997年第11期 46-47页

作者： gao li A rong

STARTING from the town of Ngapa County ill Ganzi Tibetan Autonomous Prefecture in Sichuan Province, following a rugged, winding country road, against the current of the Dajin River, we drove for about an hour covering 29 kilometers to reach Serdru Village of Pade Township, rongdar County. We met Tibetan doctor Lhamo wearing a bright national costume at the sanitation and medical station of Serdru Village. She is just over

关键词： A Tibetan Countryside Doctor Lhamo

Immune Responses of Chicken Immunizedwith Marek's Disease Vaccines

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Journal of Northeast Agricultural University(English Edition) 1996年第1期3卷 29-37页

作者： liu Zhonggui, gao rong,li Qingzhang,liu Yun, Zheng Shimin,Yan liping(Northeast Agricultural University,Harbin,150030 PR China) Northeast Agricultural University Harbin 150030 PR China

The experiment was conducted to study the dynamic changes of immune responses of chicks immunized with March's disease(MD)trivalent vaccine and turkey herpesvirus(HVT)at one day *** were found that after immunization of chicks with MD vaccines,the intcrlcukinc-2(IL-2)inductive activity and IL-2 receptor expression of T cells from thymus and spleen significantly increased,suggesting that the immunoregulativc function was markedly enhanced in the immune organs;the number of antibody-producing cells,the number and proliferative function of T cells rose markedly in Bursa Fabricius,spleen and thymus,indicating that the cellular and humoral immune responses were elevated remarkablly in the central and peripheral immune organs;the number of T and antibody-producing cells as well as the content of IgG,IgA and IgM obviously mounted in cecal tonsil, Harder tan gland mucosal lymphoid tissues of bronchus along with tears,trachea washings, bile and intestinal fluids,demonstrating that the local and mucosal immunity was raised in the respiratory and digestive tract;the levels of immune responses mentioned above in the trivalent vaccine-immuniaed chicks were apparently higher than those of HVT-immunized birds.

关键词： Marek's vaccination chick immune responses

Genetic Diversity of Recurrent Selection Populations with Ms2 Gene Assessed by Gliadins in Common Wheat (Triticum aestivum L.)

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Agricultural Sciences in China 2010年第5期9卷 615-625页

作者： JIANG Hui, gao Qing-rong, li Luo-jiang, KONG ling-rang, ZHANG Wei-dong, WU Shi-wen and YANG Ya-li State Key Laboratory of Crop Biology, Department of Agronomy, Shandong Agricultural University, Tai’an 271018, P.R.China [a] State Key Laboratory of Crop Biology Department of Agronomy Shandong Agricultural University Tai'an 271018 P.R.China

The male-sterile lines with Ms2 gene were highly evaluated in recurrent selection in wheat （Triticum aestivum L.）. Three populations C6 （population after six cycles of selection）, C7 （population after seven cycles of selection）, and C8 （population after eight cycles of selection） were constructed through recurrent selection with 12 parental materials （P）. Acid polyacrymide gel electrophoresis （A-PAGE） analysis was used to identify gliadin patterns and evaluate the genetic diversity in 12 parents and three populations. A total of 63 bands were identified, of which 17 polymorphic bands and 7 unique bands were present in populations and seven polymorphic bands and four unique bands were present in parents. The number of polymorphic and unique bands decreased gradually from C6 to C8, especially for to- and y-gliadins. The genetic distances in C6, C7, and C8 were calculated. The distributions of genetic distance were different in three recurrent selection populations. From C6 to C8, the genetic distance was 0.2687, 0.2652 and 0.1987, respectively. Statistically significant differences were detected between C7 and C8 with the T value of 37.9718. The result of cluster analysis based on genetic similarity matrix of three populations fitted well to those of principle coordinates analysis （PCoA）. Compared with 12 parents, almost all individuals of three populations are new genotypes. Most of the individuals from C6 and C7 could be divided into two groups, while most individuals of C8 were in one cluster. In conclusion, the results indicated that the genetic diversity was decreased severely according to the information revealed by A-PAGE, although some variations could be created in the recurrent selection. It was necessary to introduce diverse germplasm based on the genetic database of recurrent population to maintain and improve the breeding efficiency in the further program.

关键词： genetic diversity recurrent selection gliadins Ms2 gene Triticum aestivum L

Bulging Performance and Quality Control of Aluminum Alloy Tailor-welded Overlapping Sheets Based on Interface Friction

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 258-264页

作者： gao Tiejun gao Bowen li Weijie ZHANG Jiabin College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China Shenyang Aerospace Xinguang Group Co.L td. Shenyang 110043China

In order to solve the problem of poor formability caused by different materials and properties in the process of tailor-welded sheets forming,a forming method was proposed to change the stress state of tailor-welded sheets by covering the tailor-welded sheets with better plastic properties overlapping *** the same time,the interface friction effect between the overlapping and tailor-welded sheets was utilized to control the stress magnitude and further improve the formability and quality of the tailor-welded *** this work,the bulging process of the tailor-welded overlapping sheets was taken as the research *** alloy tailor-welded overlapping sheets bulging specimens were studied by a combination of finite element analysis and experimental *** results show that the appropriate use of interface friction between tailor-welded and overlapping sheets can improve the formability of tailor-welded sheets and control the flow of weld seam to improve the forming *** increasing the interface friction coefficient on the side of tailor-welded sheets with higher strength and decreasing that on the side of tailor-welded sheets with lower strength,the deformation of the tailor-welded sheets are more uniform,the offset of the weld seam is minimal,the limit bulging height is maximal,and the forming quality is optimal.

关键词： tailor-welded sheets overlapping sheet bulging interface friction weld seam stress

Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 192-201页

作者： Shuai li Zhen Ma Jin-Hua gao School of Science Hebei University of Science and Technology School of Electronics and Information Zhengzhou University of Light Industry School of Physics and Wuhan National High Magnetic Field Center Huazhong University of Science and Technology

We theoretically investigate the spin resolved Friedel oscillation （FO） and quasiparticle interference （QPI） in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r-2in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as *** spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment (***ález-Herrero et al.,Science 352,437 （2016）).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states （FT-LDOS）.Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity