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New Lower Bounds to Wrap-around L2-discrepancy for U-type Designs with Three-level

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Acta Mathematicae Applicatae Sinica 2019年第3期35卷 513-520页

作者： Zheng-hong WANG hong qin School of Mathematics and Statistics South-Central University for NationalitiesWuhan 430074China Faculty of Mathematics and Statistics Central China Normal UniversityWuhan 430079China

The objective of this paper is to study the issue of uniformity on three-level U-type designs in terms of the wrap-around *** on the known formula,we present a new lower bound of wrap-around L2-discrepancy for three-level U-type designs and compare it with those existing ones through figures,numerical simulation and illustrative examples.

关键词： U-type designs wrap-around L2-discrepancy lower bound

AR mutations in 28 patients with androgen insensitivity syndrome(Prader grade 0–3)

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Science China(Life Sciences) 2017年第7期60卷 700-706页

作者： Yi Wang Chunxiu Gong Xiou Wang miao qin Beo'ing Key Laboratory for Genetics of Birth Defects Center of Endocrinology Genetics and Metabolism Beo'ing Children's Hospital The Capital Medical University National center for children's health Beijing 100045 China

We investigated the androgen receptor(AR) gene mutation profiles of Chinese patients exhibiting severe androgen insensitivity syndrome(AIS) phenotypes. The present study enrolled 28 patients with genetically diagnosed AIS, who presented with severe phenotypes(Prader grade 0–3). Patients and some family members were screened via amplification and sequencing of their AR exons 1–8, including the corresponding intronic flanking regions. Luteinizing(LH), follicle-stimulating(FSH), and testosterone(T) hormone levels were found to be slightly, but not significantly, higher in patients with complete androgen insensitivity syndrome(CAIS) than in patients with partial androgen insensitivity syndrome(PAIS)(P>0.05). We identified 24 different AR mutations, including 12 that were novel. Ten patients(cases 2, 3, 10, 28, 11, 12, 19, 20, 24, and 25) were found to carry five recurrent mutations(p.Y572 S, p.P914 S, p.S176 R, p.Y782 N, and p.R841H); of these, p.Y572 S, p.S176 R, and p.Y782 N were novel. Among the mutations identified in patients with CAIS, six(66.7%) were characterized as single-nucleotide missense mutations, and six(66.7%) were found to be located in the AR ligand-binding domain(LBD). Among the mutations identified in patients with PAIS, 15(93.8%) were found to be missense, and 11(68.8%) were found to be located in the LBD. Patients 10 and 28 were determined to harbor the same missense mutation(p.P914S), but were diagnosed with CAIS and PAIS, *** hormone levels were slightly, but not significantly, elevated in patients with CAIS compared to those with PAIS. Missense mutations spanning AR exons 1–8 were the predominant form of identified mutations, and these were mostly located in the AR LBD. Approximately 50% of the identified mutations were novel, and have enriched the AR gene-mutation database. Patients harboring identical mutations were in some instances found to exhibit divergent phenotypes.

关键词： androgen insensitivity syndrome androgen receptor gene novel mutations genotype-phenotype correlation

Formation of adiabatic shearing band for high-strength Ti-5553 alloy:A dramatic thermoplastic microstructural evolution

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Defence Technology（防务技术） 2022年第11期18卷 2045-2051页

作者： Dong-yang qin Ying-gang miao Yu-long Li School of Aeronautics Northwestern Polytechnical UniversityXi'an710072China School of Civil Aviation Northwestern Polytechnical UniversityXi'an710072China

By using split Hopkinson pressure bar, optical microscopy and electronic microscopy, we investigate the influence of initial microstructures on the adiabatic shear behavior of high-strength Ti-5Al-5V-5Mo-3Cr(Ti-5553) alloy with lamellar microstructure and bimodal microstructure. Lamellar alloy tends to form adiabatic shearing band(ASB) at low compression strain, while bimodal alloy is considerably ASBresistant. Comparing with the initial microstructure of Ti-5553 alloy, we find that the microstructure of the ASB changes dramatically. Adiabatic shear of lamellar Ti-5553 alloy not only results in the formation of recrystallized β nano-grains within the ASB, but also leads to the chemical redistribution of the alloying elements such as Al, V, Cr and Mo. As a result, the alloying elements distribute evenly in the *** contrast, the dramatic adiabatic shear of bimodal alloy might give rise to the complete lamination of the globular primary a grain and the equiaxial prior β grain, which is accompanied by the dynamic recrystallization of a lamellae and β lamellae. As a result, ASB of bimodal alloy is composed of a/β nanomultilayers. Chemical redistribution does not occur in ASB of bimodal alloy. Bimodal Ti-5553 alloy should be a promising candidate for high performance armors with high mass efficiency due to the processes high dynamic flow stress and excellent ASB-resistance.

关键词： Titanium alloys Armor High loading rate Adiabatic shearing band Dynamic phase transformation

Boundary Layer to a System of Viscous Hyperbolic Conservation Laws

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Acta Mathematicae Applicatae Sinica 2008年第3期24卷 523-528页

作者： Xiao-hong qin Department of Applied Mathematics Nanjing University of Science and Technology Nanjing 210094 China

In this paper, we investigate the large-time behavior of solutions to the initial-boundary value problem for n × n hyperbolic system of conservation laws with artificial viscosity in the half line （0, ∞）. We first show that a boundary layer exists if the corresponding hyperbolic part contains at least one characteristic field with negative propagation speed. We further show that such boundary layer is nonlinearly stable under small initial perturbation. The proofs are given by an elementary energy method.

关键词： Viscous hyperbolic conservation laws boundary layer asymptotic stability

On a General Class of Semiparametric Hazards Regression Models for Recurrent Gap Times

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Acta Mathematicae Applicatae Sinica 2019年第3期35卷 549-563页

作者： qin JIANG Hui ZHAO hong qin Department of Statistics Central China Normal UniversityWuhan 430079China Department of Mathematics Huanggang Normal UniversityHuanggang 438000China Department of Statistics Zhongnan University of Economics and LawWuhan 430073China

In the article,we investigate a general class of semiparametric hazards regression models for recurrent gap *** general class includes the proportional hazards model,the accelerated failure time model and the accelerated hazards models as special *** model is flexible in modelling recurrent gap times since a covariate effect is identified as having two separate components,namely a time-scale change on hazard progression and a relative hazards *** order to infer the model parameters,the procedure is proposed based on estimating *** asymptotic properties of the proposed estimators are established and the finite sample properties are investigated via simulation *** addition,a lack of fit test is presented to assess the adequacy of the model and an application of data from a bladder cancer study is reported for illustration.

关键词： gap times model checking recurrent events estimating equations semiparametric model

Boundary-layer disturbances subjected to free-stream turbulence and simulation on bypass transition

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Applied Mathematics and Mechanics(English Edition) 2016年第8期37卷 967-986页

作者： hong qin Ming DONG Department of Mechanics Tianjin University Tianjin 300072 China Tianjin Key Laboratory of Modern Engineering Mechanics Tianjin 300072 China

The phenomena associated with the entrainment of free-stream turbulence （FST） into boundary-layer flows are relevant for a number of subjects. It has been be- lieved that the continuous spectra of the Orr-Sommerfeld （O-S）/Squire equations describe the entrainment process, and thus they are used to specify the inlet condition in simulation of bypass transition. However, Dong and Wu （Dong, M. and Wu, X. On continuous spectra of the Orr-Sommerfeld/Squire equations and entrainment of free-stream vortical disturbances. Journal of Fluid Mechanics, 732, 616-659 （2013）） pointed out that continuous spectra exhibit several non-physical features due to neglecting the non-parallelism. They further proposed a large-Reynolds-number asymptotic approach, and showed that the non-parallelism is a leading-order effect even for the short-wavelength disturbance, for which the response concentrates in the edge layer. In this paper, the asymptotic solution is verified numerically by studying its evolution in incompressible boundary layers. It is found that the numerical results can be accurately predicted by the asymptotic solution, implying that the latter is adequate for moderate Reynolds numbers. By introducing a series of such solutions as the inflow perturbations, the bypass transition is investigated via the direct numerical simulation （DNS）. The transition processes, including the evolution of streaks, the amplification of secondary-instability modes, and the emergence of turbulent spots, agree with the experimental observations.

关键词： free-stream turbulence (FST) bypass transition boundary layer asymptotic direct numerical simulation (DNS)

A Note on Ranking in the Plackett-Luce Model for Multiple Comparisons

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Acta Mathematicae Applicatae Sinica 2019年第4期35卷 885-892页

作者： Jing LUO hong qin Department of Statistics South-central University for Nationalities Wuhan 430074 China Department of Statistics Zhongnan University of Economics and Law Wuhan 430073 China Department of Statistics Central China Normal University Wuhan 430079 China

Ranking and rating individuals is a fundamental problem in multiple comparisons. One of the most well-known approaches is the Plackett-Luce model, in which the ordering is decided by the maximum likelihood estimator. However, the maximum likelihood estimate(MLE) does not exist when some individuals are never ranked lower than others or lose all their races. In this note, we proposed a penalized likelihood method to address this problem. As the penalized parameter goes to zero, the penalized MLE converges to the original MLE. Further, there exists a critical point in which the penalized likelihood ranking is independent of the choice of the penalized parameter. Several numerical examples are provided.

关键词： multiple comparisons penalized likelihood ranking Plackett-Luce model

Breaking the diffraction limit in far field by planar metalens

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Science China(Physics,Mechanics & Astronomy) 2017年第4期60卷 86-87页

作者： Fei qin MingHui hong Institute of Photonics Technology Jinan University Department of Electrical and Computer Engineering National University of Singapore

Optical lens is of fundamental importance in both scientific researches and industrial communities, especially for the aspects of optical focusing and imaging. In traditional optics, the light modulation property is limited by the Rayleigh Criterion （0.6 λ/NA）, and therefore the development of an ideal lens that produces sub-diffraction limit focusing and imaging has been a dream of lens makers all the time. Intensive effort has been made to break this barrier for centuries, however, all the reported techniques suffer from certain limitations for general applications, such as near-field operation, small field of view, or object dyeing which works only for a narrow-class of samples [1-3].

关键词： focusing Rayleigh Criterion optics planar dream communities

A Note on Supersaturated Design

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Acta Mathematicae Applicatae Sinica 2022年第3期38卷 729-739页

作者： Na ZOU hong qin School of Statistics and Mathematics Zhongnan University of Economics and LawWuhan 430073China Faculty of Mathematics and Statistics Central China Normal UniversityWuhan 430079China

Supersaturated designs are common choice for screening *** paper studies the properties of supersaturated *** give new lower bounds of E(s^(2))-criterion and E(f_(NOD))-*** linkages between the combined/double design and its original design are firstly provided,and the lower bounds of E(s^(2)) and E(f_(NOD)) for the combined/double design are also ***,the close relationship between the minimum Lee-moment aberration criterion and the criteria for optimal supersaturated designs is *** theoretical results can be used to construct or search for optimal supersaturated designs in *** results are also provided,which lend further support to our theoretical findings.

关键词： supersaturated design E(s^(2))-criterion E(f_(NOD))-criterion minimum Lee-moment aberration criterion foldover double