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排序方式: 共有4865条查询结果,搜索用时 15 毫秒
331.
介绍用新型HT46R47型单片机和模糊控制技术实现的电饭煲。他具有电路简单、成本低廉、节省能源、安全可靠等特点。 相似文献
332.
大型抽样调查总是采用分层多阶段抽样.分层多阶段抽样若采用自加权的抽样设计,则总体总量的估计量形式简单,易于计算.本文提出了分层三阶段及以上抽样的自加权抽样设计方法. 相似文献
333.
334.
We show the validity of the one-term Edgeworth expansion for Studentized asymptotically linear statistics based on samples drawn without replacement from finite populations. Replacing the moments defining the expansion by their estimators, we obtain an empirical Edgeworth expansion. We show the validity of the empirical Edgeworth expansion in probability. 相似文献
335.
Based on the martingale version of the Skorokhod embedding Heyde and Brown (1970) established a bound on the rate of convergence in the central limit theorem (CLT) for discrete time martingales having finite moments of order 2+2δ with 0<δ1. An extension for all δ>0 was proved in Haeusler (1988). This paper presents a rather quick access based solely on truncation, optional stopping, and prolongation techniques for martingale difference arrays
to obtain other upper bounds for sup (φbeing the standard normal d.f.) yielding weak sufficient conditions for the asymptotic normality of
. It is shown that our approach also yields two types of martingale central limit theorems with random norming. 相似文献
336.
R. Xu Y.J. Yan O. Kühn 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,19(3):293-305
Separating multidimensional problems into that of a relevant system which is coupled to a bath of harmonic oscillators is
a common concept in condensed phase theory. Focusing on the specific problem of intramolecular proton transfer in an isolated
tropolone derivative, we consider the reactive proton moving in the plane of the molecule as the system and the remaining
substrate normal modes as the bath. An all-Cartesian system-plus-substrate Hamiltonian is constructed employing density functional
theory. It is then used to determine the temperature-dependent effective reduced reaction Hamiltonian and the state-to-state
dissipation rates induced via the system-substrate coupling up to the bi-quadratic order. The important substrate modes for the T1-relaxation and the pure T2-dephasing rates, which are either intra- or inter-well in nature, are identified numerically and analyzed physically with
molecular details.
Received 19 November 2001 and Received in final form 19 February 2002 相似文献
337.
Spatial Nonparametric Regression Estimation: Non-isotropic Case 总被引:3,自引:0,他引:3
Zu-di Lu Xing ChenInstitute of Systems Science Academy of Mathematics Systems Sciences Chinese Academy of Sciences. Beijing ChinaDepartment of Statistics Yunnan University Kunming China 《应用数学学报(英文版)》2002,18(4):641-656
Data collected on the surface of the earth often has spatial interaction. In this paper, a non-isotropic mixing spatial data process is introduced, and under such a spatial structure a nonparametric kernel method is suggested to estimate a spatial conditional regression. Under mild regularities, sufficient conditions are derived to ensure the weak consistency as well as the convergence rates for the kernel estimator. Of interest are the following: (1) All the conditions imposed on the mixing coefficient and the bandwidth are simple; (2) Differently from the time series setting, the bandwidth is found to be dependent on the dimension of the site in space as well; (3) For weak consistency, the mixing coefficient is allowed to be unsummable and the tendency of sample size to infinity may be in different manners along different direction in space; (4) However, to have an optimal convergence rate, faster decreasing rates of mixing coefficient and the tendency of sample size to infinity along each direction a 相似文献
338.
339.
Philip L. H. Yu Yijun Sun Bimal K. Sinha 《Annals of the Institute of Statistical Mathematics》2002,54(4):861-878
In this paper we discuss the problem of estimating the common mean of a bivariate normal population based on paired data as well as data on one of the marginals. Two double sampling schemes with the second stage sampling being either a simple random sampling (SRS) or a ranked set sampling (RSS) are considered. Two common mean estimators are proposed. It is found that under normality, the proposed RSS common mean estimator is always superior to the proposed SRS common mean estimator and other existing estimators such as the RSS regression estimator proposed by Yu and Lam (1997, Biometrics, 53, 1070–1080). The problem of estimating the mean Reid Vapor Pressure (RVP) of regular gasoline based on field and laboratory data is considered. 相似文献
340.