带有测量误差的相关数据的CUSUM控制图

实际中测量误差不仅存在而且在某些情况下还影响质量控制的表现,本文将考虑带有测量误差的相关数据的监控问题. 为检测这类数据的飘移,我们给出了一个基于极大似然比检验的CUSUM控制图及其多种情况下的可控与失控的ARL.模拟结果显示, 当过程负相关时, 我们提出的CUSUM控制图具有良好的表现.     

Error Estimate of the Fourier Collocation Method for the Benjamin-Ono Equation

In this paper, the Fourier collocation method for solving the generalized Benjamin-Ono equation with periodic boundary conditions is analyzed. Stability of the semi-discrete scheme is proved and error estimate in H1/2-norm is obtained.     

残差自回归半参数模型的参数估计

研究了残差自回归半参数模型的参数估计,运用广义最小二乘法估计了参数部分．用随机模拟说明了运用广义最小二乘（GLSE）估计出的参数部分优于运用普通最小二乘法（OKSE）得到的估计．     

A direct method of solving singular integral equations with the Hilbert kernel

In this paper we consider a class of second-kind singular integral equations with Hilbert kernel on the unit circumference. We theoretically substantiate a solution method based on an interpolation-type operator.     

抛物型积分微分方程的非协调$H^{1}$-Galerkin混合有限元方法

H^1-Galerkin nonconforming mixed finite element methods are analyzed for integro-differential equation of parabolic type. By use of the typical characteristic of the elements, we obtain that the Galerkin mixed approximations have the same rates of convergence as in the classical mixed method, but without LBB stability condition.     

Functional a posteriori error estimates for incremental models in elasto-plasticity

We consider incremental problem arising in elasto-plastic models with isotropic hardening. Our goal is to derive computable and guaranteed bounds of the difference between the exact solution and any function in the admissible (energy) class of the problem considered. Such estimates are obtained by an advanced version of the variational approach earlier used for linear boundary-value problems and nonlinear variational problems with convex functionals [24, 30]. They do no contain mesh-dependent constants and are valid for any conforming approximations regardless of the method used for their derivation. It is shown that the structure of error majorant reflects properties of the exact solution so that the majorant vanishes only if an approximate solution coincides with the exact one. Moreover, it possesses necessary continuity properties, so that any sequence of approximations converging to the exact solution in the energy space generates a sequence of positive numbers (explicitly computable by the majorant functional) that tends to zero.      

SG-0: a small standard grid for DFT quadrature on large systems

We report the development of a new standard quadrature grid for DFT calculations. Standard Grid 0 (SG-0) is designed to be approximately half as large as, and to provide approximately half the accuracy of, the established SG-1 grid. It is based on MultiExp and Lebedev quadrature for radial and angular coordinates, respectively. We find that SG-0 is typically 50% faster than SG-1 for energy, gradient, and hessian calculations for the exchange-correlation energy. This leads to a 35-38% speedup in the total gradient and hessian computations, and we particularly recommend its use for preliminary calculations on moderately large biochemical systems. It has been implemented as the default grid for DFT calculations in the Q-Chem 3.0 package.     

不确定离散时间输入饱和系统的鲁棒预见控制

本文研究一类具有输入饱和的不确定离散时间系统的鲁棒预见控制问题.与以往对误差信号和系统方程取差分不同,本文引入状态辅助变量,利用系统状态向量与辅助变量之差代替通常的状态差分,使得输入饱和不确定离散系统的扩大误差系统的构造成为可能.另外,本文推导的扩大误差系统不再包含误差向量,这不仅降低系统的阶数而且允许输出矩阵带有不确...     

Maps and inverse maps in open quantum dynamics

Two kinds of maps that describe evolution of states of a subsystem coming from dynamics described by a unitary operator for a larger system, maps defined for fixed mean values and maps defined for fixed correlations, are found to be quite different for the same unitary dynamics in the same situation in the larger system. An affine form is used for both kinds of maps to find necessary and sufficient conditions for inverse maps. All the different maps with the same homogeneous part in their affine forms have inverses if and only if the homogeneous part does. Some of these maps are completely positive; others are not, but the homogeneous part is always completely positive. The conditions for an inverse are the same for maps that are not completely positive as for maps that are. For maps defined for fixed mean values, the homogeneous part depends only on the unitary operator for the dynamics of the larger system, not on any state or mean values or correlations. Necessary and sufficient conditions for an inverse are stated several different ways: in terms of the maps of matrices, basis matrices, density matrices, or mean values. The inverse maps are generally not tied to the dynamics the way the maps forward are. A trace-preserving completely positive map that is unital cannot have an inverse that is obtained from any dynamics described by any unitary operator for any states of a larger system.     

Distribution of selected monaural acoustical parameters in concert halls

Acoustical parameters calculated from impulse responses are often used to evaluate the characteristics of concert halls. Representative parameters are listed in the Annex of ISO 3382 and the methods of calculation and the minimum number of measurement positions are explained in detail. However, a method for selecting measurement positions is not discussed clearly, because there are wide variations in the characteristics of sound fields. This report provides basic data to solve this problem using spatial distribution characteristics of parameters in halls. Three large-scale measurement campaigns were conducted in which impulse responses were measured at 1427, 180, and 511 locations. Relatively large differences in the obtained parameters compared with well-known difference limens suggest that determining the distributions of parameter values is important. Contour maps are therefore used to display the distributions along with mean values.