复杂地面背景的红外热像合成

提出了一种新的合成地面背景红外热像的方法，建立了基于马尔可夫随机场理论的图像分割模型，获取了地面背景的标记图像；综合考虑环境、气象等因素的影响，模拟计算不同植被地面红外辐射特性；通过将红外辐射特性计算结果的灰度值赋予相应的可见光图像分割区域，实现标记图像与红外辐射特性的合成，获取复杂地面背景的红外热像。     

A simple statistical modeling of random phase reference in holographic memory

We present a simple modeling of random phase reference in holographic memory. The proposed model is analyzed by a statistical approach. Improvement on selectivity using random phase reference is shown in comparison with uniform phase plane wave reference and Gaussian beam reference. This simple and efficient model provides a physical insight and is verified by some experiments.     

扩散滤波器及其在图象放大中的应用

图象放大在图象显示、视频特技等领域有广泛的应用。当既要求图象放大质量好又要求算法简单时，传统的图象放大方法遇到了困难，其原因是未考虑到视觉的方向敏感性。本文提出了一种与视觉特点相匹配的图象放大方法一邻域扩散法，以简单的坐标变换获得了较好的图象放大效果，特别有利于硬件实现。文中分析了一种新型的二维低通数字滤波器—扩散滤波器及其频率响应特性，构造了具体实现中的扩散增量矩阵，给出了任意（N／M）×（N／M）倍放大坐标变换关系。本文的结果和放大实例也可作为视觉方向特性的一个实验证明。     

Brownian dynamics of polydisperse colloidal hard spheres: Equilibrium structures and random close packings

Recently we presented a new technique for numerical simulations of colloidal hard-sphere systems and showed its high efficiency. Here, we extend our calculations to the treatment of both 2- and 3-dimensional monodisperse and 3-dimensional polydisperse systems (with sampled finite Gaussian size distribution of particle radii), focusing on equilibrium pair distribution functions and structure factors as well as volume fractions of random close packing (RCP). The latter were determined using in principle the same technique as Woodcock or Stillinger had used. Results for the monodisperse 3-dimensional system show very good agreement compared to both pair distribution and structure factor predicted by the Percus-Yevick approximation for the fluid state (volume fractions up to 0.50). We were not able to find crystalline 3d systems at volume fractions 0.50–0.58 as shown by former simulations of Reeet al. or experiments of Pusey and van Megen, due to the fact that we used random start configurations and no constraints of particle positions as in the cell model of Hoover and Ree, and effects of the overall entropy of the system, responsible for the melting and freezing phase transitions, are neglected in our calculations. Nevertheless, we obtained reasonable results concerning concentration-dependent long-time selfdiffusion coefficients (as shown before) and equilibrium structure of samples in the fluid state, and the determination of the volume fraction of random close packing (RCP, glassy state). As expected, polydispersity increases the respective volume fraction of RCP due to the decrease in free volume by the fraction of the smaller spheres which fill gaps between the larger particles.     

再散射输运模型与K+/π+比的系统学

用含再散射效应的简单的强子输运模型,研究了AGS能量(14.6AGeV/c)下p+p、p+Au和Si+Au反应的K⁺/π⁺比值,再现了该比值由P十P到Si十Au不断增长的实验事实.CERN能量(200AGeV/c)和AGS能量下,K⁺/π⁺比值相近的实验事实也得到了解释.     

Wegner estimate for sparse and other generalized alloy type potentials

We prove a Wegner estimate for generalized alloy type models at negative energies (Theorems 8 and 13). The single site potential is assumed to be non-positive. The random potential does not need to be stationary with respect to translations from a lattice. Actually, the set of points to which the individual single site potentials are attached, needs only to satisfy a certain density condition. The distribution of the coupling constants is assumed to have a bounded density only in the energy region where we prove the Wegner estimate.     

ON THE EXPECTATION AND VARIANCE OF HAMMING DISTANCE BETWEEN TWO I.I.D RANDOM VECTORS

1.IntroductionLetFZn={0,1}"beann-dimensionalvectorspaceoverthebinaryfieldFZ={0,1}.TheHammingdistancebetweentwovectorsx=(xl,'tx.)andy=(yi,'ty.)isthenumberofcoordinateswheretheydiffer,andisdenotedbydH(x,y),dH(X,y)=ZIXi~ail.i=1TheHammingweightofxisthenumberofnon-zerocoordinates,andisdenotedbyWH(x).ObviouslyAH(x)=dH(x,0),where0isthezerovector.Thescalarproductofxandyis(x,y)=xlyl ' xestinF2.ForasetAgFZn,IAIdenotesthecardinalityofA.TheaveragedistanceinAisdefinedby*Thisresearchissupp…     

Weighted FOM and GMRES for solving nonsymmetric linear systems

This paper presents two new methods called WFOM and WGMRES, which are variants of FOM and GMRES, for solving large and sparse nonsymmetric linear systems. To accelerate the convergence, these new methods use a different inner product instead of the Euclidean one. Furthermore, at each restart, a different inner product is chosen. The weighted Arnoldi process is introduced for implementing these methods. After describing the weighted methods, we give the relations that link them to FOM and GMRES. Experimental results are presented to show the good performances of the new methods compared to FOM(m) and GMRES(m). This revised version was published online in August 2006 with corrections to the Cover Date.     

一种人机结合的真随机模拟方法

利用计算机间隔时间存储的功能，结合键盘敲击随机点过程，通过时间间隔分布的小数分布及其极限性质，给出了一种人机组合的真随机模拟方法，并指出了其计算机实现方法和在经济学以及遗传进化算法等中的应用。     

Efficient robust estimation of parameter in the random censorship model

For an open set Θ of ^k, let \s{P_θ: θ Θ\s} be a parametric family of probabilities modeling the distribution of i.i.d. random variables X₁,…, X_n. Suppose X_i's are subject to right censoring and one is only able to observe the pairs (min(X_i, Y_i), [X_i Y_i]), i = 1,…, n, where [A] denotes the indicator function of the event A, Y₁,…, Y_n are independent of X₁,…, X_n and i.i.d. with unknown distribution Q₀. This paper investigates estimation of the value θ that gives a fitted member of the parametric family when the distributions of X₁ and Y₁ are subject to contamination. The constructed estimators are adaptive under the semi-parametric model and robust against small contaminations: they achieve a lower bound for the local asymptotic minimax risk over Hellinger neighborhoods, in the Hájel—Le Cam sense. The work relies on Beran (1981). The construction employs some results on product-limit estimators.