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Asymptotic Normality of Wavelet Density Estimator under Censored Dependent Observations

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Acta Mathematicae Applicatae sinica 2012年第4期28卷 781-794页

作者： si-li NIU Department of Mathematics Tongji University

In this paper, we discuss the asymptotic normality of the wavelet estimator of the density function based on censored data, when the survival and the censoring times form a stationary α-mixing sequence. To simulate the distribution of estimator such that it is easy to perform statistical inference for the density function, a random weighted estimator of the density function is also constructed and investigated. Finite sample behavior of the estimator is investigated via simulations too.

关键词： Wavelet density estimator asymptotic normality, censored data, α-mixing, random weightedestimator

A Result on Fractional(a,b,k)-critical Covered graphs

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Acta Mathematicae Applicatae sinica 2021年第4期37卷 657-664页

作者： si-zhong ZHOU School of Science Jiangsu University of Science and TechnologyZhenjiang212100China

A fractional[a,b]-factor of a graph g is a function h from E(g)to[0,1]satisfying a≤d^(h)_(g)(v)≤b for every vertex v of g,where d^(h)_(g)(v)=∑e∈E(v)h(e)and E(v)={e=uv:u∈V(g)}.A graph g is called fractional[a,b]-covered if g contains a fractional[a,b]-factor h with h(e)=1 for any edge e of g.A graph g is called fractional(a,b,k)-critical covered if g—Q is fractional[a,b]-covered for any Q⊆V(g)with∣Q∣=*** this article,we demonstrate a neighborhood condition for a graph to be fractional(a,b,k)-critical ***,we claim that the result is sharp.

关键词： graph neighborhood fractional[a,6]-factor fractional[a.6]-covered graph fractional(a.b,k)-critical covered graph

Microstructure characterization and hydrogen storage properties study of Mg2Ni0.92M0.08（M = Ti, V, Fe or si） alloys

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Progress in Natural Science:Materials International 2018年第4期28卷 464-469页

作者： Yue Zhang Hairi Zhang Xiaoli Ding Dongming Liu Qingan Zhang Tingzhi si School of Materials Science and Engineering Anhui University of Technology

In the present study Mg2Ni-type compounds alloyed independently with Ti,V,Fe and si were successfully prepared by wet-milling followed by *** these alloyed Mg2Ni compounds exhibited a similar hydrogen storage mechanism as that of pure Mg2Ni,the dissolution of Ti,V or Fe into the Mg2NiH4lattice had a considerable catalytic effect on hydrogen desorption from additional *** further structure investigations clearly indicated that the substitution of Ti for Ni could suppress the formation of the micro-twined low-temperature phase（LT2）and promote the formation of the high-temperature phase（HT）,thus resulting in remarkably improved hydrogen desorption kinetics for the Mg2Ni0.92Ti0.08–H system.

关键词： Hydrogen storage Mg-based alloys Elemental substitution Kinetics

Automatic Circuit Extractor for HDL Description Using Program Slicing

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Journal of Computer Science & Technology 2004年第5期19卷 718-728页

作者： TunLi Yangguo si-KunLi SchoolofComputerScienceandTechnology NationalUniversityofDefenseTechnologyChangsha410073P.R.China

Design extraction and reduction have been extensively used in modern VLsi design process. The extracted and reduced design can be efficiently processed by various applications, such as formal verification, simulation, automatic test pattern generation (ATPg), etc. This paper presents a new circuit extraction method using program slicing technique, and develops an elegant theoretical basis based on program slicing for circuit extraction from Verilog description. The technique can obtain a chaining slice for given signals of interest. Compared with related researches, the main advantages of the method include that it is fine grain, it has no hardware description language (HDL) coding style limitation; it is precise and is capable of dealing with various Verilog constructions. The technique has been integrated with a commercial simulation environment and incorporated into a design process. The results of practical designs show the significant benefits of the approach.

关键词： program slicing chaining slice process dependence graph circuit extraction VLsi functional verification

Fermi Blazars in the Zwicky Transient Facility Survey:A Correlation Study

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Research in Astronomy and Astrophysics 2023年第7期23卷 64-79页

作者： si-si Sun Zhong-Xiang Wang Yi Xing Department of Astronomy School of Physics and AstronomyYunnan UniversityKunming 650091China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China

We report on our correlation analysis for theγ-ray blazars detected with the Large Area Telescope(LAT)onboard the Fermi gamma-ray Space Telescope(Fermi),for which we use the Fermi-LAT data and the optical zr and zg band data from the Zwicky Transient Facility survey in the time period approximately from 2018 July to *** start from the full sample of the Fermi-LAT blazars and find~38%of them as significant variables in bothγ-ray and optical *** the variables,which are 705 blazars,95 are selected as our targets based on the requirement for theγ-ray *** 15 out of the 95 blazars are found to show theγ-ray-optical correlations in the~3.7 yr time *** of the 15 blazars are classified as low synchrotron peaked(LSP)ones with the time lags between theγ-ray and optical bands in a range from-19 to+25 *** results generally fit the often-considered emission scenario for the LSP *** cases of showing~-100 days time lags are discussed,which require farther studies for *** analysis results suggest that among the detected significant variables,~23%LSPs can showγ-ray and optical correlations,while their averageγ-ray fluxes are above~4×10^(-8)photon cm^(-2)s^(-1).

关键词： gamma-rays:galaxies (galaxies:)quasars:general (galaxies:)BL Lacertae objects:general

A method to evaluate the bioactive function of fruit extracts of Chinese wild Citrus with microtubular activity

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Journal of Integrative Agriculture 2017年第4期16卷 867-873页

作者： gUAN Xin TAN si günther Buchholz Peter Nick ZHOU Zhi-qin College of Horticulture and Landscape Architecture Southwest University Chongqing 400716 P.R. China Molecular Cell Biology Botanical Institute Karlsruhe Institute of Technology Karlsruhe D-76128 Germany RLP AgroScience/AIPlanta-institute for Plant Research Neustadt an der Weinstrasse D-67435 Germany Laboratoire Vigne Biotechnologies et Environnement EA-3991 Universit6 de Haute-Alsace Colmar 68000 France Key Laboratory of Horticulture Science for Southern Mountainous Regions Ministry of Education Chongqing 400716 P.R. China

China is one of the most important centers of origin for Citrus genetic resources. Due to the high content of secondary metabolites, mining wild Chinese Citrus for novel medical applications is promising. In this study, extracts of Chinese wild species from different taxonomical groups were screened for potential effects on microtubules （MTs） in vitro. MT density as a readout for nucleation, and frequency distribution over MT lengths as a readout for elongation and decay were determined by quantitative image analysis via a standardized coverslJp assay using fluorescently labelled neurotubulin. Extract from peels of Citrus ichangensis Swing. strongly increased the density of MTs; whereas, extract from peels of Cfurs limon （L.） Burm.f. exerted the opposite effect. Extract from pulp of Citrus limonia Osbeck promoted MT elongation, and in addition induced a small population of very long MTs. These data suggest that wild Chinese Citrus harbour compounds that act specifically on different aspects of MT nucleation, elongation, and decay.

关键词： fruit extract natural product-based pharmaceuticals Chinese wild Citrus microtubules secondary plant metabolites

Three-dimensional adaptive finite-time guidance law for intercepting maneuvering targets

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Chinese Journal of Aeronautics 2017年第6期30卷 1985-2003页

作者： Yujie si Shenmin SONg Center for Control Theory and guidance Technology Harbin Institute of Technology Harbin 150001 China

To intercept maneuvering targets at desired impact angles, a three-dimensional terminal guidance problem is investigated in this study. Because of a short terminal guidance time, a finitetime impact angle control guidance law is developed using the fast nonsingular terminal sliding mode control theory. However, the guidance law requires the upper bound of lumped uncertainty including target acceleration, which may not be accurately obtained. Therefore, by adopting a novel reaching law, an adaptive sliding mode guidance law is provided to release the drawback. At the same time, this method can accelerate the convergence rate and weaken the chattering phenomenon to a certain extent. In addition, another novel adaptive guidance law is also derived; this ensures systems asymptotic and finite-time stability without the knowledge of perturbations *** simulations have demonstrated that all the three guidance laws have effective performances and outperform the traditional terminal guidance laws.

关键词： Adaptive control Finite-time guidance law Impact angle Sliding mode control Three-dimensional guidance law

Response Solutions for Degenerate Reversible Harmonic Oscillators with Zero-average Perturbation

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Acta Mathematica sinica,English Series 2023年第10期39卷 2006-2030页

作者： Xin Yu gUAN Jian guo si Wen si School of Statistics and Mathematics Shandong University of Finance and EconomicsJi’nan 250002P.R.China School of Mathematics Shandong UniversityJi’nan 250100P.R.China

In this paper,we consider a class of normally degenerate quasi-periodically forced reversible systems,obtained as perturbations of a set of harmonic oscillators,{x˙=y+∈f1(ωt,x,y),y˙=λx^(l)+∈f2(ωt,x,y),where 0≠λ∈R,l>1 is an integer and the corresponding involution g is(−θ,x,−y)→(θ,x,y).The existence of response solutions of the above reversible systems has already been proved in[22]if[f2(ωt,0,0)]satisfies some non-zero average conditions(See the condition(H)in[22]),here[·]denotes the average of a continuous function on T^(d).However,discussing the existence of response solutions for the above systems encounters difficulties when[f_(2)(ωt,0,0)]=0,due to a degenerate implicit function must be *** article will be doing work in this *** purpose of this paper is to consider the case where[f2(ωt,0,0)]=*** precisely,with 2pg results:(1)Forλ>˜0(seeλ˜in(2.2))and sufficiently small,response solutions exist for eachωsatisfying a weak non-resonant condition;(2)Forλgue measure such that response solutions exist for each∈E ifωsatisfies a Diophantine *** the remaining case whereλ−1[∂pf2(ωt,0,0)∂xp]>0 and l−p is even,we prove the system admits no response solutions in most regions.

关键词： Degenerate harmonic oscillators zero-average perturbation KAM theory reversible system response solutions

CHARACTERIZATIONS OF SYMMETRIC MULTISTEP RUNgE-KUTTA METHODS

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Journal of Computational Mathematics 2004年第6期22卷 791-796页

作者： Ai-guoXiao si-qinggan SchoolofMathematicsandComputationalScience XiangtanUniversityXiangtan411105China SchoolofMathematicsSciencesandComputingTechnology CentralSouthUniversityChangsha410075China

Some characterizations for symmetric multistep Runge-Kutta(RK) methods are obtained. Symmetric two-step RK methods with one and two-stages are presented. Numerical examples show that symmetry of multistep RK methods alone is not sufficient for long time integration for reversible Hamiltonian systems. This is an important difference between one-step and multistep symmetric RK methods.

关键词： Multistep Runge-Kutta method Symmetry