Flash memory efficient LTL model checking

As the capacity and speed of flash memories in form of solid state disks grow, they are becoming a practical alternative for standard magnetic drives. Currently, most solid-state disks are based on NAND technology and much faster than magnetic disks in random reads, while in random writes they are generally not.So far, large-scale LTL model checking algorithms have been designed to employ external memory optimized for magnetic disks. We propose algorithms optimized for flash memory access. In contrast to approaches relying on the delayed detection of duplicate states, in this work, we design and exploit appropriate hash functions to re-invent immediate duplicate detection.For flash memory efficient on-the-fly LTL model checking, which aims at finding any counter-example to the specified LTL property, we study hash functions adapted to the two-level hierarchy of RAM and flash memory. For flash memory efficient off-line LTL model checking, which aims at generating a minimal counterexample and scans the entire state space at least once, we analyze the effect of outsourcing a memory-based perfect hash function from RAM to flash memory.Since the characteristics of flash memories are different to magnetic hard disks, the existing I/O complexity model is no longer sufficient. Therefore, we provide an extended model for the computation of the I/O complexity adapted to flash memories that has a better fit to the observed behavior of our algorithms.     

基于平行截面上轮廓之间重构问题的研究

研究了基于平行截面上两多边形轮廓重构的基本问题,给出了利用体积最大化作为度量标准来求得一个"较好"并且合法的重构的目标函数,然后得出:其中一个多边形轮廓在其所在的截面上沿着法向平移、在截面内平移和在截面内等比例缩放都不影响最大化体积后的结果。该结论对于三维实体的可视化和几何造型领域具有重要的实用价值。     

The use of genetic algorithms for assessment of high voltage fields

There are several numerical methods for calculation of electric fields but they need some sort of experience and trial and error to get the correct solution. A genetic algorithm (GA) based approach is used to eliminate the need for the experience and to save time and effort spent in the trial and error. Two enhancement techniques, namely, Refreshment Method and No-Twins Method, are used with the GA operators to improve the performance of the GA in assessment of high voltage fields. The performance of these two enhancement techniques has been studied for computing the electrostatic field in high voltage applications.     

蛇形益智魔方的三维路径求解算法

蛇形益智魔方是智力魔方的一种,由27个两两相连的小正方体组成。文章通过计算机图形学的概念建立空间三维坐标模型,对模型中关键点进行分析归类,对空间中每个方块体可能的坐标点进行了递归公式推导,最后利用三维空间坐标的遍历算法来寻找蛇形魔方所有可能的解,指出了模型的使用前景。     

分布式系统上异步算法的终止

本文论述了一种检测分布式系统上异步算法终止的有效方法．     

误差反向传播算法的数学推导及实现步骤

提供了人工神经网络的一种算法-误差反向传播算法的数学推导方法及上机实现步骤.     

微型计算机在换热器控制系统中的应用

本文论述了微型计算机和可编程控制器（ＰＣ）控制换热器系统温度的硬件设计和控制方法。     

基于改进模拟植物生长算法的输电网络扩展规划

输电网络规划是一个复杂的组合优化问题,若以选择线路回数为变量抽象出模型,则输电网扩展问题可以归结为一类整数规划问题.对模拟植物生长算法进行改进,形成了适于解整数规划问题的改进模拟植物生长算法,并将此算法应用到电力系统输电网络扩展规划中.为了加快算法收敛,采用了Kruskal算法来获取初始点,提出了一种快速判别网络连通的算法.最后,实例计算结果表明了该方法的可行性.     

LMS算法收敛步长的精确求解

本文提出了用步长阀值上下限的算术平均值去计算收敛步长的新方法,通过LMS算法失调量的精确分析,寻出了计算步长的公式.计算机模拟结果证实了本文方法及其步长计算公式的准确性.