卡尔曼滤波器在光电经纬仪中的应用

为了解决光电经纬仪电视跟踪系统脱靶量滞后对控制系统跟踪精度及稳定性的影响，将预测滤波技术应用到光电跟踪系统中，提出了极坐标下卡尔曼滤波算法，目标模型采用等速运动并附有时间相关的随机加速度，增加了延时补偿。仿真结果表明，跟踪误差减小，当跟踪目标从视场消失时，控制系统按照预测的目标信息跟踪。     

Tuning fuzzy power-system stabilizers in multi-machine systems by global optimization algorithms based on efficient domain partitions

In this paper, the problem of global tuning of fuzzy power-system stabilizers (FPSSs) present in a multi-machine power system in order to damp the power system oscillations is considered. In particular, it is formulated as a problem of global minimization of a multiextremal black-box function over a multidimensional hyperinterval. A global optimization technique, recently proposed, is used for solving the stated problem: the search hyperinterval is partitioned into smaller hyperintervals and the objective function is evaluated only at two vertices corresponding to the main diagonal of the generated hyperintervals, thus avoiding unnecessary ponderous simulations. Then, the performances of this technique are numerically compared with ones of a genetic algorithm (GA).     

基于免疫算法的Hopfield神经网络多用户检测器

提出的基于免疫算法的Hopfield神经网络多用户检测器，将扰乱的Hopfield神经网络多用户检测器的输出作为免疫算法的初始种群，利用了免疫算法的全局收敛的特点，从而克服了Hopfield易收敛到局部能量最小点的缺点。理论分析和仿真结果表明：该检测器具有良好的抗多址干扰和抗远近效应的能力。     

Efficient Legendre moment computation for grey level images

Legendre orthogonal moments have been widely used in the field of image analysis. Because their computation by a direct method is very time expensive, recent efforts have been devoted to the reduction of computational complexity. Nevertheless, the existing algorithms are mainly focused on binary images. We propose here a new fast method for computing the Legendre moments, which is not only suitable for binary images but also for grey level images. We first establish a recurrence formula of one-dimensional (1D) Legendre moments by using the recursive property of Legendre polynomials. As a result, the 1D Legendre moments of order p, L_p=L_p(0), can be expressed as a linear combination of L_p-1(1) and L_p-2(0). Based on this relationship, the 1D Legendre moments L_p(0) can thus be obtained from the arrays of L₁(a) and L₀(a), where a is an integer number less than p. To further decrease the computation complexity, an algorithm, in which no multiplication is required, is used to compute these quantities. The method is then extended to the calculation of the two-dimensional Legendre moments L_pq. We show that the proposed method is more efficient than the direct method.     

空间柔性机械臂三维动力学数值仿真

本文应用ｄ＇Ａｌｅｍｂｅｒｔ－Ｌａｇｒａｎｇｅ原理，对由基座、（ｎ－１）个柔性连杆及端部负载组成，相互用柱铰连接的柔性链式多体系统进行建模；对在空间技术中，具有一刚杆，两柔杆加上刚性负载所组成的三维机械臂系统，采用Ｇｅａｒ算法进行数值仿真。仿真结果比较符合实际，从而在柔性多体系统的数学模型为刚性常微分方程的情况下，为解决其数值仿真问题，特别是三维问题的数值仿真取得了进展。     

直接斜率波前复原算法的控制效果分析

建立自适应光学系统功率谱抑制函数的概念，分析了采用直接斜率波前复原算法的自适应当光学系统的控制效果，理论分析与６１单元自适应光学系统上的实验结果表明，直接斜率波前复原算法将导致控制效果下降。     

3^n阶矩阵乘法的分块算法

针对３＾ｎ阶矩阵的乘法运行，给出了一种分块算法，其乘法运行量比常规的矩阵乘法计算方法和补零的基－２算法都有所减少。     

Homology modelling of annexin I: implicit solvation improves side-chain prediction and combination of evaluation criteria allows recognition of different types of conformational error

Annexin I homology models were built from the annexin V crystalstructure. Three methods for side-chain prediction were testedbased on molecular mechanics conformational search, the useof a rotamer database, or a combination of these two methods.We showed that rotamer-based methods were more efficient andthat molecular mechanics energy minimizations, prior to rotamerselection, did not afford clearly improved predictions. Modelsbuilt in vacuo and with an implicit solvation term were comparedwith the annexin I crystal structure which became availableduring the course of this study. The analysis of solvation energies,root mean square deviations, Xi angles and hydrogen bonds showedthat models built with implicit solvation were of better quality.In annexin V, repeat III displays A-B and D-E loop conformationsquite different from other repeats. Since the sequence differencessuggest that repeat III in annexin I might present a conformationsimilar to other repeats, two annexin I models with differentrepeat III conformations were built and compared to determinewhether the correct conformation could have been predicted.We show that using a combination of evaluation criteria, itis possible to discriminate unequivocally between the nativeand the incorrect fold, stressing that only one criterion shouldnot be used to evaluate protein structures.     

256比特的混沌分组密码

由于密码分析研究的进展及DES自身的弱点,原64比特的DES将不能作为数据加密的标准算法而长期存在。在原来工作的基础上,本文提出了256比特的分组密码方案。密码算法由基于混沌映射的数字滤波器构造。