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151.
A. Meister 《Mathematical Methods of Statistics》2007,16(1):63-76
This paper addresses the statistical problem of density deconvolution under the condition that the density to be estimated
has compact support. We introduce a new estimation procedure, which establishes faster rates of convergence for smooth densities
as compared to the optimal rates for smooth densities with unbounded support. This framework also allows us to relax the usual
condition of known error density with non-vanishing Fourier transform, so that a nonparametric class of densities is valid;
therefore, even the shape of the noise density need not be assumed. These results can also be generalized for fast decaying
densities with unbounded support. We prove optimality of the rates in the underlying experiment and study the practical performance
of our estimator by numerical simulations.
相似文献
152.
Yi-rang Yuan 《应用数学学报(英文版)》2007,23(2):255-268
For a coupled system of multiplayer dynamics of fluids in porous media,the characteristic finiteelement domain decomposition procedures applicable to parallel arithmetic are put forward.Techniques suchas calculus of variations,domain decomposition,characteristic method,negative norm estimate,energy methodand the theory of prior estimates are adopted.Optimal order estimates in L~2 norm are derived for the error inthe approximate solution. 相似文献
153.
生长曲线模型中回归系数阵的极大似然估计的精确分布 总被引:2,自引:0,他引:2
对于生长曲线模型,基于理论发展和应用效果的考虑,本文引入了Gauss型误差.在此误差下,本文研究了模型中回归系数阵的极大似然估计的精确分布,求出了此分布的密度和特征函数. 相似文献
154.
1引言 有限体积方法[l]一l’]作为守恒型的离散技术,被广泛应用于工程计算领域.文【2,3} 基于分片常数和分片常向量函数空间,对二维驻定对流扩散方程提出了一类非协调混合 有限体积(Covolume)格式,证明了格式具有。(hl/2)收敛精度.但该格式要求对偶剖分 比较规则,即采用重 相似文献
155.
The logarithmic norm. History and modern theory 总被引:1,自引:0,他引:1
Gustaf Söderlind 《BIT Numerical Mathematics》2006,46(3):631-652
In his 1958 thesis Stability and Error Bounds, Germund Dahlquist introduced the logarithmic norm in order to derive error bounds in initial value problems, using differential inequalities that distinguished between forward and reverse time integration. Originally defined for matrices, the logarithmic norm can be extended to bounded linear operators, but the extensions to nonlinear maps and unbounded operators have required a functional analytic redefinition of the concept.This compact survey is intended as an elementary, but broad and largely self-contained, introduction to the versatile and powerful modern theory. Its wealth of applications range from the stability theory of IVPs and BVPs, to the solvability of algebraic, nonlinear, operator, and functional equations. In memory of Germund Dahlquist (1925–2005).AMS subject classification (2000) 65L05 相似文献
156.
157.
Christian Maes 《Journal of statistical physics》1990,61(3-4):667-681
An anisotropic lattice gas dynamics is investigated for which particles on
d
jump to empty nearest neighbor sites with (fast) rate –2 in a specified direction and some particular configuration-dependent rates in the other directions. The model is translation and reflection invariant and is particle conserving. The space coordinate in the fast-rate direction is rescaled by –1. It follows that the density field converges in probability, as 0, to the corresponding solution of a nonlinear diffusion-type equation. The microscopic fluctuations about the deterministic macroscopic evolution are determined explicitly and it is found that the stationary fluctuations decay via a power law (1/r
d
) with the direction dependence of a quadrupole field. 相似文献
158.
Tomasz Rolski 《Queueing Systems》1989,4(1):17-26
We study single server periodic queues in the day equilibrium conditions. The following characteristics of interest are considered at time of dayt: Vp(t)-the work load, Lp(t)-the number of customers and up(t)-the departure rate. We give relationships between E[Vp(t)], E[Lp(t)] and up(t). We also prove that E[Vp(t)] < and E[Lp(t)] < provided the second moment of the service time is finite. 相似文献
159.
R. Schilling 《Journal of statistical physics》1988,53(5-6):1227-1235
A one-dimensional kinetic Ising model with Glauber dynamics subjected to a slow continuous quench to zero temperature is studied. For a rather general class of cooling schemes, described by a time-dependent temperatureT(t), the mean domain sizeL(t) is calculated along with the residual energye
res
(r) as a function of the cooling rater. If the attempt frequency =0 exp(–/kT), entering into the transition rates, is temperature dependent (i.e., the barrier is non-zero), the asymptotic growth ofL(t) is given byL()–L(t)~exp[–/kT(t)]. For this case the residual energy exhibits a power-law behaviore
res(r) ~r
/2(1 + ) forr small, where =4J/ andJ is the nearest neighbor coupling constant. For =0 and for certain cooling schemes the residual energy is zero andL(t)~t1/2, independent ofr. 相似文献
160.