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Modified likelihood ratio test for homogeneity in normal mixtures with two samples

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Applied Mathematics(A Journal of Chinese Universities) 2008年第1期23卷 113-119页

作者： QIN Yong-song lei qing-zhu School of Math. Sci. Guangxi Normal Univ. Guilin 541004 China.

This paper investigates the modified likelihood ratio test（LRT） for homogeneity in normal mixtures of two samples with mixing proportions unknown. It is proved that the limit distribution of the modified likelihood ... 详细信息

关键词： mixture model likelihood ratio test asymptotic distribution.

Joint empirical likelihood confidence regions for a finite number of quantiles under strong mixing samples

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Applied Mathematics(A Journal of Chinese Universities) 2015年第1期30卷 44-54页

作者： lei qing-zhu QIN Yong-song Department of Mathematics Guangxi Normal University

In this paper, we obtain the joint empirical likelihood confidence regions for a finite number of quantiles under strong mixing samples. As an application of this result, the empirical likelihood confidence intervals ... 详细信息

关键词： strong mixing sample quantile confidence region blockwise empirical likelihood.

Empilrical Likelihood for Non-parametric Regression Models with Missing Responses:Multiple Design Case

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Acta Mathematicae Applicatae Sinica 2011年第1期27卷 1-12页

作者： qing-zhu lei Yong-song Qin School of Mathematical Sciences Guangxi Normal University Guilin Guangxi 541004 China

Empirical likelihood （EL） ratio statistic on θ=g（x） is constructed based on the inverse probability weighted imputation approach in a nonparametric regression model Y = g（x）＋ε （x ∈ [0, 1]p） with fixed designs and missing responses, which asymptotically has X1^2 distribution. This result is used to obtain a EL based confidence interval on θ.

关键词： Nonparametric regression empirical likelihood missing at random confidence interval

Tile selection method based on error minimization for photomosaic image creation

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Frontiers of Computer Science 2021年第3期15卷 165-172页

作者： Hongbo ZHANG Xin GAO Jixiang DU qing lei Lijie YANG Department of Computer Science and Technology Huaqiao UniversityXiamen 361021China Fujian Key Laboratory of Big Data Intelligence and Security Huaqiao UniversityXiamen 361021China Xiamen Key Laboratory of Computer Vision and Pattern Recognition Huaqiao UniversityXiamen 361021China School of Computer Science and Technology Harbin Institute of TechnologyShenzhen 518055China

Photomosaic images are composite images composed of many small images called *** its overall visual effect,a photomosaic image is similar to the target image,and photomosaics are also called“montage art”.Noisy blocks and the loss of local information are the major obstacles in most methods or programs that create photomosaic *** solve these problems and generate a photomosaic image in this study,we propose a tile selection method based on error minimization.A photomosaic image can be generated by partitioning the target image in a rectangular pattern,selecting appropriate tile images,and then adding them with a weight *** on the principles of montage art,the quality of the generated photomosaic image can be evaluated by both global and local *** the proposed framework,via an error function analysis,the results show that selecting a tile image using a global minimum distance minimizes both the global error and the local error ***,the weight coefficient of the image superposition can be used to adjust the ratio of the global and local ***,to verify the proposed method,we built a new photomosaic creation dataset during this *** experimental results show that the proposed method achieves a low mean absolute error and that the generated photomosaic images have a more artistic effect than do the existing approaches.

关键词： photomosaic image tile image target image error minimization mean absolute error

Empirical Likelihood for Response Differences in Two Linear Regression Models with Missing Data

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Acta Mathematicae Applicatae Sinica 2015年第4期31卷 963-976页

作者： Yong-song QIN Tao QIU qing-zhu lei Department of Mathematics Guangxi Normal University Guilin

Oonsider two linear models Xi = U＇β ＋ ei, Yj = V1/2y ＋ ηj with response variables missing at random. In this paper, we assume that X, Y are missing at random （MAR） and use the inverse probability weighted imputation to produce ＇complete＇ data sets for X and Y. Based on these data sets, we construct an empirical likelihood （EL） statistic for the difference of X and Y （denoted as A）, and show that the EL statistic has the limiting distribution of X~, which is used to construct a confidence interval for A. Results of a simulation study on the finite sample performance of EL-based confidence intervals on A are reported.

关键词： linear model inverse probability weighted imputation empirical likelihood missing at random confidence interval

Fluctuation control for many-to-one routing in wireless sensor networks

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The Journal of China Universities of Posts and Telecommunications 2012年第6期19卷 35-44页

作者： JING Gang JIA lei XIE Li-hua HU qing-lei LIU Shuai School of Control Science and Engineering Shandong University Exquisitus Centre for E-CitySchool of Electrical and Electronic EngineeringNanyang Technological University Department of Control Science and Engineering Harbin Institute of Technology

This paper presents a distributed and adaptive fluctuation control scheme for many-to-one routing （FCM） in wireless sensor networks. Unlike well-known topology control schemes, the primary design objective is to reduce the fluctuation which happens due to overload of sensors in a data collection tree. More specifically, an estimation model of a sensor available capacity based on the number of its neighbors is proposed. In addition, this paper proposes a parent selection mechanism by three-way handshake. With such model and the selection mechanism, it is ensured that the load of a sensor does not exceed its available capacity. Finally, an adaptive maintenance mechanism is proposed to adjust the estimation of a sensor available capacity as the network environment changes. Simulation results demonstrate the effectiveness of the scheme.

关键词： wireless sensor network fluctuation control schemes many-to-one routing congestion control tree topologies

Effects of P addition on the microstructure and mechanical properties of Mg–5%Sn–1.25%Si alloy

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International Journal of Minerals,Metallurgy and Materials 2014年第3期21卷 289-294页

作者： Hao-ran Geng qing-lei Wang Peng Liu Ming Wu School of Material Science and Engineering University of Jinan Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials University of Jinan Jinan Jinzhong Electronic Scale Company Ltd.

The effects of Al-P addition on the microstructure and mechanical properties of as-cast Mg–5%Sn–1.25%Si magnesium alloy were investigated. The results show that the phases of the as-cast alloy are composed of α-Mg, Mg2 Sn, Mg2 Si, little P, and AlP. The Chinese character shape Mg2 Si phase changes into a granular morphology by P addition because AlP can act as a heterogeneous nucleation core for the Mg2 Si phase. When 0.225wt% of Al–3.5%P alloy is added, the mechanical properties of the Mg–5%Sn–1.25%Si alloy are greatly improved, and the tensile strength increases from 156 to 191 MPa, an increase of 22.4% compared to the alloy without P addition. When the amount of Al–3.5%P reaches 0.300wt%, a segregation phenomenon occurs in the granular Mg2 Si phase, and the tensile strength and hardness decrease though the elongation increases.

关键词： magnesium alloys microstructure mechanical properties phosphorus

Flame behavior, shock wave, and instantaneous thermal field generated by unconfined vapor-liquid propylene oxide/air cloud detonation

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Defence Technology（防务技术） 2023年第7期25卷 18-32页

作者： Cong-liang Ye qing-lei Du Li-juan Liu Qi Zhang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China School of Safety Science and Emergency Management Wuhan University of TechnologyWuhanHubei430070China

Energy output and heating effects are essential for vapor-liquid fuel/air cloud detonation in the fuel-air explosive(FAE) applications or explosion accidents. The purpose of this study is to examine the dynamic large-size flame behavior, shock wave propagation law, and instantaneous thermal field generated by unconfined vapor-liquid propylene oxide(PO)/air cloud detonation. Based on computational fluid dynamics(CFD) and combustion theory, a numerical simulation is used to study the detonation process of a PO/air cloud produced by a double-event fuel-air explosive(DEFAE) of 2.16 kg. The large-scale flame behavior is characterized. The flame initially spreads radially and laterally in a wing shape. Subsequently,the developed flame increases with a larger aspect ratio. Moreover, the propagation laws of shock waves at different heights are discussed. The peak pressure of 1.3 m height level with a stepwise decline is obviously different from that of the ground with an amplitude of reversed ’N’ shape. In the vast majority of the first 6.9 m, the destructive effect of the shock wave near the ground is greater than that of the shock wave at 1.3 m height. Furthermore, the dynamic instantaneous isothermal field is *** scaling relationship of various isotherms in the instantaneous thermal field with the flame and initial cloud is summarized. The comprehensive numerical model used in this study can be applied to determine the overpressure and temperature distribution in the entire fuel/air cloud detonation field,providing guidance for assessing the extent of damage caused by DEFAE detonation.

关键词： Numerical simulation Fuel-air explosive Fuel/air cloud Flame Shock wave Thermal field

Empirical Likelihood for Quantiles Under Associated Samples

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Acta Mathematicae Applicatae Sinica 2015年第1期31卷 71-80页

作者： Ying-hua LI Yong-song QIN qing-zhu lei School of Mathematics and Statistics Guangxi Normal University

The construction of confidence intervals for quantiles of a population under a associated sample is studied by using the blockwise technique. It is shown that the blockwise empirical likelihood （EL） ratio statistic is asymptotically X2-type distributed, which is used to obtain EL-based confidence intervals for quantiles of a population.

关键词： quantile associated sample blockwise empirical likelihood confidence interval