运动单站无源定位中的坐标转换矩阵的分析

运动单站测角、角变化率无源定位中，观测方程和状态方程建立在不同坐标系中。本文引入一个坐标转换矩阵把状态向量在两个坐标系中的坐标联系起来，推导了坐标转换矩阵，计算出由平台姿态误差带来的坐标转换矩阵误差，并应用到跟踪滤波方程中，最后给出计算机仿真结果。     

二阶问题Adini元的误差估计(英文)

The main aim of this paper is to have an accurate analysis on the famous Adini's element for the second order problems under to the anisotropic meshes.We firstly show that the interpolation of Adini's element satisfy the anisotropic property.Then the optimal error estimate is obtained without the regularity assumption on the meshes.     

一类随机保费率下的风险模型

引入随机变量保费率,对古典风险模型进行推广,主要研究随机保费率下的风险模型,用随机过程和鞅论的方法得出破产概率、末离前最大盈余分布、破产前瞬时盈余与破产赤字的联合分布等精算量分布的具体表达式.     

算子值酉随机矩阵及其渐近自由性

该文在算子值非交换概率空间上引入半标准酉随机矩阵的概念, 证明了它是算子值Haar酉元的矩阵模型,并给出了半标准酉随机矩阵的渐近自由判定定理.     

Blocking Probability Based Hierarchical Storage Design in VoD Systems

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Spurious,zeroth-order entropy generation along a kinked wall

Numerical entropy generation is studied in the case of steady, subsonic Euler flow along a kinked solid wall. For a standard upwind finite volume discretization the numerical entropy error, a component of the global discretization error, appears to be zeroth-order in mesh size. Two possible causes of the zeroth-order entropy error are studied. First an investigation is made of the local truncation error on a kinked grid. Although this error also appears to be zeroth-order in the neighbourhood of the kink, it probably does not cause the zeroth-order entropy error. Next a study is made of the existence of a singularity in the exact solution. Probably, the Euler flow solution is singular at the kink in the wall. The form of this likely singularity is unknown. Therefore the construction of a computational method which uses a priori knowledge about the singularity is not possible. Finally it is shown by numerical experiments that the subsonic Euler flow along a kinked wall still can be computed with vanishing entropy errors by using an appropriate sequence of continuously curved walls which converge to the kinked wall in the limit of zero mesh width.     

Backus—Gilbert方法对不精确数据解的误差估计

1 引言 1968年地质学家G Backus and F Gilbert给出了求解线性(非线性)矩问题的一种方法,用来求解地球物理反问题。后来称这种方法为B-G方法。过去几年,数学家们从理论和应用方面研究了B-G方法。从理论上分析了其收敛性并给出了误差估计。第一类算子方程在不同函数空间的离散化得到不同形式的矩问题。[4]、[5]研究了再生核空间和小波空间的B-G方法。并用于信号恢复问题。由于矩问题的不适定性,有必要分析B-G方法解的正则性,本文得到了B-G方法对不精确数据的误差估计,从而证明了B-G方法是—种正则化方法。 考虑线性矩问题     

40Gb/s(STM-2 5 6)高速时分复用传输技术前景展望

随着技术的发展 ,4 0 Gb/ s(STM- 2 5 6 )作为 10 Gb/ s(STM- 6 4)传输业务颗粒的后续者 ,开始逐渐为业界熟悉。就 4 0 Gb/ s这一新兴技术的市场推动因素、应用场合以及影响 4 0 Gb/ s传输的一些关键技术作了介绍 ,并对其将来的应用前景作出展望     

Aliasing probability transients

Test data reduction for digital systems is often accomplished through the use of a feedback shift register. This method, known as signature analysis, can exhibit error masking or aliasing. Recent analysis has shown that the use of a primitive polynomial for the register feedback can reduce the probability of aliasing. In this work we demonstrate that not all primitive polynomials are created equal. Some primitive polynomials can have very large transients in their aliasing probability. For example, 1 +X ¹³ +X ³³ can exhibit an aliasing probability more than a million times larger than its asymptotic value of 2^–33. An evaluation procedure is presented which can identify polynomials with good transient characteristics. Some recommended feedback polynomials are given.     

分组密码算法扩散特性的一种统计分析

针对巳有的分组密码扩散特性的依赖性测试方法，分析了其中各统计量的概率分布，使这种统计分析方法有了较完整的理论基础，指出 NESSIE用该方法评价AES决赛算法的不足。给出了运用该统计分析方法对分组密码算法做依赖性测试时抽取样本容量的下界。