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Local Rate of Convergence in the Functional Limit Theorem for Increments of a Fractional Brownian Motion 被引量:1
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作者 LIU Yonghong DING Ding ZHOU Xia 《数学进展》 北大核心 2025年第1期197-211,共15页
In this paper,we present local functional law of the iterated logarithm for Cs?rg?-Révész type increments of fractional Brownian motion.The results obtained extend works of Gantert[Ann.Probab.,1993,21(2):104... In this paper,we present local functional law of the iterated logarithm for Cs?rg?-Révész type increments of fractional Brownian motion.The results obtained extend works of Gantert[Ann.Probab.,1993,21(2):1045-1049]and Monrad and Rootzén[Probab.Theory Related Fields,1995,101(2):173-192]. 展开更多
关键词 fractional Brownian motion INCREMENT local functional law of the iterated logarithm large deviation small deviation
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Deep brain implantable microelectrode arrays for detection and functional localization of the subthalamic nucleus in rats with Parkinson’s disease 被引量:1
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作者 Luyi Jing Zhaojie Xu +11 位作者 Penghui Fan Botao Lu Fan Mo Ruilin Hu Wei Xu Jin Shan Qianli Jia Yuxin Zhu Yiming Duan Mixia Wang Yirong Wu Xinxia Cai 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期439-452,共14页
The subthalamic nucleus(STN)is considered the best target for deep brain stimulation treatments of Parkinson’s disease(PD).It is difficult to localize the STN due to its small size and deep location.Multichannel micr... The subthalamic nucleus(STN)is considered the best target for deep brain stimulation treatments of Parkinson’s disease(PD).It is difficult to localize the STN due to its small size and deep location.Multichannel microelectrode arrays(MEAs)can rapidly and precisely locate the STN,which is important for precise stimulation.In this paper,16-channel MEAs modified with multiwalled carbon nanotube/poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(MWCNT/PEDOT:PSS)nanocomposites were designed and fabricated,and the accurate and rapid identification of the STN in PD rats was performed using detection sites distributed at different brain depths.These results showed that nuclei in 6-hydroxydopamine hydrobromide(6-OHDA)-lesioned brains discharged more intensely than those in unlesioned brains.In addition,the MEA simultaneously acquired neural signals from both the STN and the upper or lower boundary nuclei of the STN.Moreover,higher values of spike firing rate,spike amplitude,local field potential(LFP)power,and beta oscillations were detected in the STN of the 6-OHDA-lesioned brain,and may therefore be biomarkers of STN localization.Compared with the STNs of unlesioned brains,the power spectral density of spikes and LFPs synchronously decreased in the delta band and increased in the beta band of 6-OHDA-lesioned brains.This may be a cause of sleep and motor disorders associated with PD.Overall,this work describes a new cellular-level localization and detection method and provides a tool for future studies of deep brain nuclei. 展开更多
关键词 functional localization Implantable microelectrode arrays Parkinson’s disease Subthalamic nucleus
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Local Functional Limit Theorems of Increments for Brownian Motion 被引量:6
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作者 Fu Qing GAO Yong Hong LIU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2018年第7期1074-1086,共13页
In this paper, we present a local Csorgo- Revesz type functional limit theorem for increments of Brownian motion and give its convergence rate. The results also extend the functional forms of Levy's modulus of contin... In this paper, we present a local Csorgo- Revesz type functional limit theorem for increments of Brownian motion and give its convergence rate. The results also extend the functional forms of Levy's modulus of continuity for Brownian motion. 展开更多
关键词 Keywords Brownian motion INCREMENT local functional limit rate of convergence large deviation small deviation
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LOCAL C-SEMIGROUPS AND LOCAL C-COSINE FUNCTIONS 被引量:1
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作者 高明杵 《Acta Mathematica Scientia》 SCIE CSCD 1999年第2期201-213,共13页
This paper is concerned with the local C-semigroups and local C-cosine functions without the assumption that the image of C is dense in a Banach space X, First, the sufficient and necessary conditions for a local C-se... This paper is concerned with the local C-semigroups and local C-cosine functions without the assumption that the image of C is dense in a Banach space X, First, the sufficient and necessary conditions for a local C-semigroup and a C-cosine function to be the restriction of a global C-semigroup and a global C-cosine function to an interval are given, respectively, Secondly, it is characterized for a closed operator to be the generator of a local C-semigroup and a local C-cosine function, respectively. 展开更多
关键词 local C-semigroups local C-cosine functions asymptotic C-resolvent
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MULTI-SCALE COHERENT STRUCTURES IN TURBULENT BOUNDARY LAYER DETECTED BY LOCALLY AVERAGED VELOCITY STRUCTURE FUNCTIONS 被引量:1
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作者 刘建华 姜楠 +1 位作者 王振东 舒玮 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第4期495-504,共10页
The time sequence of longitudinal velocity component at different vertical locations in turbulent boundary layer was finely measured in a wind tunnel. The concept of coarse_grained velocity structure functions, which ... The time sequence of longitudinal velocity component at different vertical locations in turbulent boundary layer was finely measured in a wind tunnel. The concept of coarse_grained velocity structure functions, which describes the relative motions of straining and compressing for multi_scale eddy structures in turbulent flows, was put forward based on the theory of locally multi_scale average. Based on the consistency between coarse_grained velocity structure function and Harr wavelet transformation,detecting method was presented, by which the coherent structures and their intermittency was identified by multi_scale flatness factor calculated by locally average structure function. Phase_averaged evolution course for multi_scale coherent eddy structures in wall turbulence were extracted by this conditional sampling to educe scheme. The dynamics course of multi_scale coherent eddy structures and their effects on statistics of turbulent flows were studied. 展开更多
关键词 turbulent boundary layer coherent structure flatness factor intermittency locally averaged velocity structure function
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Differentiability of Convex Functions in Locally Convex Spaces(Ⅰ)──Continuous Convex Functions and Gateaux Differentiability 被引量:3
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作者 吴从 程立新 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1994年第1期7-12,共6页
The aim of this paper is to investigate the differentiability(Gateaux differentiabllity and subdifferentiability) of continuous convex functions on locally convex spaces and to study the behaviour of some important re... The aim of this paper is to investigate the differentiability(Gateaux differentiabllity and subdifferentiability) of continuous convex functions on locally convex spaces and to study the behaviour of some important results for this research area in locally convex spaces. 展开更多
关键词 ss: DIFFERENTIABILITY CONVEX function localLY CONVEX space
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The nonlocal solution of two parallel cracks in functionally graded materials subjected to harmonic anti-plane shear waves 被引量:5
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作者 Jun Liang Shiping Wu Shanyi Du Center for Composite Materials and Structure,Harbin Institute of Technology,Harbin 150001,China 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2007年第4期427-435,共9页
In this paper, the dynamic interaction of two parallel cracks in functionally graded materials (FGMs) is investigated by means of the non-local theory. To make the analysis tractable, the shear modulus and the mater... In this paper, the dynamic interaction of two parallel cracks in functionally graded materials (FGMs) is investigated by means of the non-local theory. To make the analysis tractable, the shear modulus and the material density are assumed to vary exponentially with the coordinate vertical to the crack. To reduce mathematical difficulties, a one-dimensional non-local kernel is used instead of a twodimensional one for the dynamic problem to obtain stress fields near the crack tips. By use of the Fourier transform, the problem can be solved with the help of two pairs of dual integral equations, in which the unknown variables are the jumps of displacements across the crack surfaces. To solve the dual integral equations, the jumps of displacements across the crack surfaces are expanded in a series of Jacobi polynomials. Unlike the classical elasticity solutions, it is found that no stress singularity is present at the crack tips. The non-local elastic solutions yield a finite hoop stress at the crack tips. The present result provides theoretical references helpful for evaluating relevant strength and preventing material failure of FGMs with initial cracks. The magnitude of the finite stress field depends on relevant parameters, such as the crack length, the distance between two parallel cracks, the parameter describing the FGMs, the frequency of the incident waves and the lattice parameter of materials. 展开更多
关键词 CRACK The non-local theory Stress waves functionally graded materials
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Functional localization of the cortical motor area in the brain Electrocorticogram analysis
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作者 Tao Jiang Xiaoming Wu Binggang Ye Sijuan Huang 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第19期1480-1485,共6页
The method for rapidly, precisely and non-invasively localizing functional regions of the brain is a problem in neuromedicine research. Cortical electrostimulation is the optimal localization method during brain surge... The method for rapidly, precisely and non-invasively localizing functional regions of the brain is a problem in neuromedicine research. Cortical electrostimulation is the optimal localization method during brain surgery, with a degree of accuracy of approximately 5 mm. However, electrostimulation can damage the cerebral cortex, trigger epilepsy, and extend the operation time. Studies are required to determine whether cortical motor regions can be localized by wavelet analysis from electrocorticograms. In this study, based on wavelet analysis of electrocorticograms, a selection of algorithms for classification of the mu rhythm in the motor regions utilizing experimental data was verified. Results demonstrated that a characteristic quantity of energy ratio in the reconstructed signal was filtered in the d6 (7.81-15.62 Hz) band prior to and following motion events. A characteristic threshold was considered to be 40%. The accuracy of localization detection was 93%. The degree of accuracy was less than 5 mm. The present study avoided the problems of cerebral cortex injury and epilepsy onset, with an operation time of 60 seconds. Therefore, wavelet analysis on electrocorticogram is feasible for localizing cortical motor regions. Furthermore, this localization technique is accurate, safe and rapid. 展开更多
关键词 functional localization ELECTROCORTICOGRAM mu rhythm event-related desynchronization wavelet analysis neural regeneration
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Construction Theory of Function on Local Fields 被引量:1
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作者 Weiyi Su 《Analysis in Theory and Applications》 CSCD 2015年第1期25-44,共20页
We establish the construction theory of function based upon a local field Kp as underlying space. By virture of the concept of pseudo-differential operator, we introduce "fractal calculus" (or, p-type calculus, or,... We establish the construction theory of function based upon a local field Kp as underlying space. By virture of the concept of pseudo-differential operator, we introduce "fractal calculus" (or, p-type calculus, or, Gibbs-Butzer calculus). Then, show the Jackson direct approximation theorems, Bermstein inverse approximation theorems and the equivalent approximation theorems for compact group D(C Kp) and locally compact group Kp^+-(= Kp), so that the foundation of construction theory of function on local fields is established. Moreover, the Jackson type, Bernstein type, and equivalent approximation theorems on the HOlder-type space C^σ(Kp), σ 〉0, are proved; then the equivalent approximation theorem on Sobolev-type space Wr(Kp), σ≥0, 1≤r 〈∞, is shown. 展开更多
关键词 Construction theory of function local field fractal calculus approximation theorem HOlder-type space.
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AN ALGORITHM TO MINIMIZED LOCALLY LIPSCHITZIAN FUNCTION
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作者 田蔚文 张连生 +1 位作者 董炳华 濮定国 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1996年第1期31-48,共18页
This paper gives a method of descent for the locally Lipschitzian function. It is assumed that the generalized subgradient set of the differentiable point is a singleton point. We introduce an implementable algorithm ... This paper gives a method of descent for the locally Lipschitzian function. It is assumed that the generalized subgradient set of the differentiable point is a singleton point. We introduce an implementable algorithm which is globally convergent. Numerical examples show the implementation and efficiency of the algorithm . 展开更多
关键词 localLY LIPSCHITZIAN function SUBGRADIENT convergence.
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Dipole and charge effects of chloroaluminum phthalocyanine revealed by local work function measurements at sub-molecular level
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作者 Huanjun Song Na Li +6 位作者 Hao Zhu Zhantao Peng Wenhui Zhao Haoran Chen Wei Chen Yongfeng Wang Kai Wua 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第3期429-432,共4页
Work function plays a significant role in surface chemistry. Local work function provides the information of local d/pole-d/pole interaction and charge distribution between adsorbates and substrate, highlighting the l... Work function plays a significant role in surface chemistry. Local work function provides the information of local d/pole-d/pole interaction and charge distribution between adsorbates and substrate, highlighting the local charge effect of the targeted spot which is normally smeared out in conventional average work function measurements. Chloroaluminum phthalocyanine (CIA1Pc), an important optoelectronic molecule with a permanent dipole moment pointing from the Pc ring to the ending CI atom, adsorbed on Au(111) in either Cl-up or Cl-down configuration. Scanning tunneling microscopy/spectroscopy measurements revealed that at the centers of Cl-up and CI-down molecules, the local work functions changed oppositely with respect to the Au(111) substrate. At their Pc lobes, however, the local work functions unanimously increased due to charging effect of the indole lobes in the CIAIPc molecule. 展开更多
关键词 Chloroaluminum phthalocyanine local work function Dipole orientation Scanning tunneling microscopy Surface dipole
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Differentiability of Convex Functions in Locally Convex Spaces(Ⅱ)──Frechet
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作者 王晓敏 程立新 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1997年第1期1-4,共4页
DifferentiabilityofConvexFunctionsinLocallyConvexSpaces(II)──FrechetDifferentiabilityWUCongxinWANGXiaominCHE... DifferentiabilityofConvexFunctionsinLocallyConvexSpaces(II)──FrechetDifferentiabilityWUCongxinWANGXiaominCHENGLixin吴从aaay,王晓敏... 展开更多
关键词 王晓 Differentiability of Convex functions in locally Convex Spaces Frechet
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A STUDY ON THE WEIGHT FUNCTION OF THE MOVING LEAST SQUARE APPROXIMATION IN THE LOCAL BOUNDARY INTEGRAL EQUATION METHOD 被引量:4
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作者 Long Shuyao Hu De’an (Department of Engineering Mechanics,Hunan University,Changsha 410082,China) 《Acta Mechanica Solida Sinica》 SCIE EI 2003年第3期276-282,共7页
The meshless method is a new numerical technique presented in recent years.It uses the moving least square(MLS)approximation as a shape function.The smoothness of the MLS approximation is determined by that of the bas... The meshless method is a new numerical technique presented in recent years.It uses the moving least square(MLS)approximation as a shape function.The smoothness of the MLS approximation is determined by that of the basic function and of the weight function,and is mainly determined by that of the weight function.Therefore,the weight function greatly affects the accuracy of results obtained.Different kinds of weight functions,such as the spline function, the Gauss function and so on,are proposed recently by many researchers.In the present work,the features of various weight functions are illustrated through solving elasto-static problems using the local boundary integral equation method.The effect of various weight functions on the accuracy, convergence and stability of results obtained is also discussed.Examples show that the weight function proposed by Zhou Weiyuan and Gauss and the quartic spline weight function are better than the others if parameters c and α in Gauss and exponential weight functions are in the range of reasonable values,respectively,and the higher the smoothness of the weight function,the better the features of the solutions. 展开更多
关键词 weight function meshless methods local boundary integral equation method moving least square approximation
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Extended Kantorovich method for local stresses in composite laminates upon polynomial stress functions 被引量:1
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作者 Bin Huang Ji Wang +3 位作者 Jianke Du Yan Guo Tingfeng Ma Lijun Yi 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第5期854-865,共12页
The extended Kantorovich method is employed to study the local stress concentrations at the vicinity of free edges in symmetrically layered composite laminates subjected to uniaxial tensile load upon polynomial stress... The extended Kantorovich method is employed to study the local stress concentrations at the vicinity of free edges in symmetrically layered composite laminates subjected to uniaxial tensile load upon polynomial stress functions. The stress fields are initially assumed by means of the Lekhnitskii stress functions under the plane strain state. Applying the principle of complementary virtual work,the coupled ordinary differential equations are obtained in which the solutions can be obtained by solving a generalized eigenvalue problem. Then an iterative procedure is established to achieve convergent stress distributions. It should be noted that the stress function based extended Kantorovich method can satisfy both the traction-free and free edge stress boundary conditions during the iterative processes. The stress components near the free edges and in the interior regions are calculated and compared with those obtained results by finite element method(FEM). The convergent stresses have good agreements with those results obtained by three dimensional(3D) FEM. For generality, various layup configurations are considered for the numerical analysis. The results show that the proposed polynomial stress function based extended Kantorovich method is accurate and efficient in predicting the local stresses in composite laminates and computationally much more efficient than the 3D FEM. 展开更多
关键词 Kantorovich method Polynomial stress function Composite laminates local stresses 3D FEM
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On Local Integrated Cosine Functions
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作者 石金娥 郑维行 《Northeastern Mathematical Journal》 CSCD 2001年第1期21-26,共6页
Suppose X is a Banach space, and A is a closed operator. We give some equivalent conditions between A generating a local integrated cosine functions and the existence of solutions of abstract Cauchy problems.
关键词 local k times integrated cosine function GENERATOR k times integrated family of second order
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MULTIPLIERS ON WEIGHTED FUNCTION SPACES OVER LOCALLY COMPACT VILENKIN GROUPS
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作者 Zhu Yueping (Nantong Teachers College, China) 《Approximation Theory and Its Applications》 2002年第2期65-71,共7页
In this note, we consider the multipliers on weighted function spaces over totally disconnected locally compact abelian groups (Vilenkin groups). Firstly we show an (H1 ,L ) multiplier result. We also give an (Hap ,Ha... In this note, we consider the multipliers on weighted function spaces over totally disconnected locally compact abelian groups (Vilenkin groups). Firstly we show an (H1 ,L ) multiplier result. We also give an (Hap ,Hap) multiplier result under a similiar condition of Lu Yang type. In section 2, we obtain a result about the boundedness of multipliers on weighted Besov spaces. 展开更多
关键词 MATH MULTIPLIERS ON WEIGHTED function SPACES OVER localLY COMPACT VILENKIN GROUPS
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Application of pharmacokinetics local model to evaluaterenal function
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作者 WANWeixing CAoGuoxian 《Nuclear Science and Techniques》 SCIE CAS CSCD 1999年第1期28-30,共3页
The pharmacokinetics local model was used to evaluate renal function. Some typical kinds of renal function cases, normal or disorder, were selected to be imaged with SPECT and those data measured were treated by the p... The pharmacokinetics local model was used to evaluate renal function. Some typical kinds of renal function cases, normal or disorder, were selected to be imaged with SPECT and those data measured were treated by the pharmacokinetics local model computer program (PLM). The results indicated that parameters, including peak value, peak time, inflexion time, half-excretion time, and kinetic equation played and important role in judging renal function. The fact confirms that local model is very useful in evaluating renal function. 展开更多
关键词 药物动力学 定域模型 肾功能
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Calibration Functions of Local Magnitude ML in China
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作者 Yan Zunguo,Li Puli and Xue JunrongSermoiogical Institute of Wuhan,SSB,Wuhan 430071,China 《Earthquake Research in China》 1994年第4期40-59,共20页
On the basis of the local magnitude scale for earthquakes in China and using the data observed by main regional networks in China from 1985 to 1986,the regional calibration functions RLE(△)(suitable for Eastern China... On the basis of the local magnitude scale for earthquakes in China and using the data observed by main regional networks in China from 1985 to 1986,the regional calibration functions RLE(△)(suitable for Eastern China)and RLW(△)(suitable for Western China)are established through the statistic analysis of magnitude residuals and study of the average attenuation shape of the maximal phase of near shocks,and the regions in which they apply are defined.For Eastern China,For Western China, 展开更多
关键词 local MAGNITUDE CALIBRATION function
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The Theory of Vector-Valued Function in Locally Convex Space
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作者 Lixin Ma 《Applied Mathematics》 2012年第8期903-906,共4页
In this paper, the vector-valued regular functions are extended to the locally convex space. The residues theory of the functions in the locally convex space is achieved. Thereby the Cauchy theory and Cauchy integral ... In this paper, the vector-valued regular functions are extended to the locally convex space. The residues theory of the functions in the locally convex space is achieved. Thereby the Cauchy theory and Cauchy integral formula are extended to the locally convex space. 展开更多
关键词 localLY CONVEX SPACE REGULAR function RESIDUE
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LOCAL MEDIAN ESTIMATION OF VARIANCE FUNCTION
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作者 杨瑛 W.C.Ip +1 位作者 Y.K.Kwan P.Y.K.Kwan 《Acta Mathematica Scientia》 SCIE CSCD 2004年第1期28-38,共11页
This paper considers local median estimation in fixed design regression problems. The proposed method is employed to estimate the median function and the variance function of a heteroscedastic regression model. Strong... This paper considers local median estimation in fixed design regression problems. The proposed method is employed to estimate the median function and the variance function of a heteroscedastic regression model. Strong convergence rates of the proposed estimators are obtained. Simulation results are given to show the performance of the proposed methods. 展开更多
关键词 HETEROSCEDASTICITY nonparametric median regression strong convergence rate variance function local median estimation
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