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Empirical likelihood for right censored data with covariables

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Science China Mathematics 2014年第6期57卷 1275-1286页

作者： he shuyuan LIANG Wei School of Mathematical Sciences Capital Normal University School of Mathematical Sciences Xiamen University

For complete observation and p-dimensional parameter θ defined by an estimation equation, empirical likelihood method of construction of confidence region is based on the asymptotic χp2 distribution of -2 log（EL ratio）. For right censored lifetime data with covariables, however, it is shown in literature that -2 log（EL ratio） converges weakly to a scaled χp2 distribution, where the scale parameter is a function of unknown asymptotic covariance matrix. The construction of confidence region requires estimation of this scale parameter. In this paper, by using influence functions in the estimating equation, we show that -2 log（EL ratio） converges weakly to a standard χp2 distribution and hence eliminates the procedure of estimating the scale parameter.

关键词： empirical likelihood linear regression right censoring

UNIFORM　CONVERGENCY　FOR　WEIGHTED　PERIODOGRAM　OF　STATIONARY　LINEAR　RANDOM　FIELDS

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Chinese Annals of Mathematics,Series B 1995年第3期16卷 331-340页

作者： he shuyuan(Department of Probability and Statistics, Beijing University, Beijing 100871, China.) BEIJING UNIV DEPT PROBABIL & STATBEIJING 100871PEOPLES R CHINA

Let {Xn; n ∈ N2} be a two dimensionally indexed linear stationary random field generated by a 1/4 martingale difference white noise. The logarithm uniform convergency resulte for the weighted periodogram of is proved.

关键词： Periodogram Random field Martingale difference Log-convergency.

The LIL Convergence for Stationary Linear Random Field

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Acta Mathematica Sinica,English Series 1996年第4期12卷 385-397页

作者： he shuyuan Department of Probability and Statistics Peking University Beijing, 100871 China Department of Probability and Statistics Peking University Beijing China

Let Y={Y_n;n∈N^2} be a stationary linear random field generated by a two- dimensional martingale difference. Where N^2 denotes the two dimensional integer lattice. The main purpose of this paper is to obtain the LIL ... 详细信息

关键词： Stationary linear random field 1/4 Martingale difference LIL convergency.

Theory of optimal blocking for fractional factorial split-plot designs

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Science China Mathematics 2005年第5期48卷 649-656页

作者： Al Mingyao & he shuyuan Key Laborartory of Pure and Applied Mathematics, School of Mathematical Sciences, Peking University, Beijing 100871, China 1. Key Laborartory of Pure and Applied Mathematics School of Mathematical Sciences Peking University 100871 Beijing China

The issue of optimal blocking for fractional factorial split-plot (FFSP) designs is considered under the two criteria of minimum aberration and maximum estimation capacity. The criteria of minimum secondary aberration (MSA) and maximum secondary estimation capacity (MSEC) are developed for discriminating among rival nonisomorphic blcoked FFSP designs. A general rule for identifying MSA or MSEC blocked FFSP designs through their blocked consulting designs is established.

关键词： blocking consulting design estimation capacity minimum secondary aberration fractional factorial split-plot design.

CONVERGENCY OF The MAXIMUM OF PERIODOGRAM

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Systems Science and Mathematical Sciences 1995年第3期8卷 260-269页

作者： he shuyuan(Department of Probability and Statistics, Peking University, Beijing 100871,China) 北京大学概率统计系北京

ＣＯＮＶＥＲＧＥＮＣＹＯＦＴＨＥＭＡＸＩＭＵＭＯＦＰＥＲＩＯＤＯＧＲＡＭ￥ＨＥＳｈｕｙｕａｎ（ＤｅｐａｒｔｍｅｎｔｏｆＰｒｏｂａｂｉｌｉｔｙａｎｄＳｔａｔｉｓｔｉｃｓ，ＰｅｋｉｎｇＵｎｉｖｅｒｓｉｔｙ，Ｂｅｉｊｉｎｇ... 详细信息

ＣＯＮＶＥＲＧＥＮＣＹＯＦＴＨＥＭＡＸＩＭＵＭＯＦＰＥＲＩＯＤＯＧＲＡＭ￥ＨＥＳｈｕｙｕａｎ（ＤｅｐａｒｔｍｅｎｔｏｆＰｒｏｂａｂｉｌｉｔｙａｎｄＳｔａｔｉｓｔｉｃｓ，ＰｅｋｉｎｇＵｎｉｖｅｒｓｉｔｙ，Ｂｅｉｊｉｎｇ１００８７１，Ｃｈｉｎａ）Ａｂｓｔ...

关键词： Stationary sequence periodogram trigonometric polynomial strong convergence.

heAVY RANDOM CENSORING LIMIT TheOREMS

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Systems Science and Mathematical Sciences 1999年第3期12卷 246-250页

作者： he shuyuan(Department of Probability and Statistics, Peking University, Beijing 100871, China) 北京大学概率统计系北京 100871

In this paper, we present some limit distribution theorems for Kaplan-Meierestimator in a randomly heavy censoring model.

关键词： Point process vague topology right censoring

Hierarchical Self-Assembly Promoted Circularly Polarized Luminescence Enhancement and Handedness Inversion of Metal–Organic helicate

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CCS Chemistry 2024年第9期6卷 2198-2209页

作者： shuyuan Zheng Guofeng Liu School of Chemical Science and Engineering Advanced Research InstituteTongji UniversityShanghai 200092

In-depth studies of hierarchical self-assembly with chirality inversion and asymmetry amplification are indispensable for understanding the chiral transfer rule in assembly systems and construction of circularly polarized luminescence(CPL)active ***,a coordination-driven primary assembly of pyrene-based chiral ligand and Zn(OTf)2 was employed for the construction of homochiral metal–organic helicate with a triple helix structure,tunable emission color,and significant chirality *** excitingly,the metal–organic helicate further assembled into well-ordered hierarchical nanoarchitectures with the aid of C–H⋯πinteraction andπ–πstacking,showing significant CPL enhancement and unexpected handedness ***,the|glum|increased from 5.20×10^(−5) to 5.60×10^(−2),and the|gabs|rose from 3.80×10^(−4) to 1.04×10^(−2) over the entire hierarchical self-assembly *** multiple supramolecular interactions not only endowed the resultant metal–organic helicate with efficient chirality transmission and tunable emission color but also guided the(supra)molecular building block of metal–organic helicate organizing into the hierarchically chiral nanoarchitecture in a directional *** work provides insight into the metal–organic helicate-mediated hierarchical self-assembly and aids the development of CPLactive materials with dynamic chirality modulation and enhanced chiroptical performance.

关键词： supramolecular chirality inversion circularly polarized luminescence metal-organic helicate hierarchically chiral assembly chirality amplification

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估计不同阶段和环境下的设备可靠性

北京大学学报（自然科学版） 2008年第3期44卷 331-334页

作者：何书元赵宇房祥忠北京大学数学科学学院北京100871 北京航空航天大学工程系统工程系北京100083

同型号设备的可靠性根据不同的使用环境发生变化。随着环境指标的不断恶化或改善,可靠性形成环境的函数称为可靠性曲线。估计出这条曲线后,就可以对未知环境下的设备可靠性给出合理的预测。在不同的试验阶段,可靠性曲线的形状一般有显... 详细信息

同型号设备的可靠性根据不同的使用环境发生变化。随着环境指标的不断恶化或改善,可靠性形成环境的函数称为可靠性曲线。估计出这条曲线后,就可以对未知环境下的设备可靠性给出合理的预测。在不同的试验阶段,可靠性曲线的形状一般有显著的不同。作者利用全体试验数据估计最后试验阶段的可靠性曲线,对于对数正态总体研究不同试验阶段的可靠性曲线的估计问题,给出了估计方法,证明了估计量的一致强相合性,并用计算机模拟试验说明方法的可用性。

关键词：可靠性对数正态分布环境

Experimental and numerical study on ignition and combustion characteristics of boron-magnesium composite powders

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Particuology 2024年第1期84卷 12-29页

作者： shuyuan Liu Luyang Han Hongmei Liu Yingkai Song Linlin Liu Songqi Hu Science and Technology on Combustion Internal Flow and Thermo-Structure LaboratoryNorthwestern Polytechnical UniversityXi'an710072China School of Mechanical Engineering and Rail Transit Changzhou UniversityChangzhou213164China Shanghai Institute of Space Propulsion Shanghai201112China Shanghai Engineering Research Center of Space Engine Shanghai201112China

A high-pressure laser ignition and combustion system with adjustable oxidizer gas atmosphere is established to investigate the ignition and combustion characteristics of boron-magnesium(BM)com-posite *** ignition and combustion model of BM powders is established and validated in the present *** results show that increasing water content,O_(2) content and Mg content all result in shorter ignition delay time of BM powders,among which the effect of water content is the most ***,ignition delay time increases as pressure *** combustion time decreases with increasing Mg content and ambient pressure but increases with water *** the increase of O_(2) content,combustion time of BM powders first increases and then decreases,which means a critical O_(2) content exists above which combustion time *** results show that there exists a trade-off between ignition and combustion performance of BM composite powders.

关键词： Boron magnesium powder Laser ignition Ignition and combustion model Reaction mechanism Numerical model