基于取整划分函数的k 匿名算法

提出一种基于取整划分函数的k匿名算法,并从理论上证明该算法在非平凡的数据集中可以取得更低的上界.特别地,当数据集大于2k2时,该算法产生的匿名化数据的匿名组规模的上界为k+1;而当待发布数据表足够大时,算法所生成的所有匿名组的平均规模将足够趋近于k.仿真实验结果表明,该算法是有效而可行的.     

基于权值范围设置的多模型稳定切换控制研究

针对线性加权多模型切换过程中权值难以确定问题,提出了具有Lyapunov函数的多模型稳定切换的充分条件,依据该充分条件可以确定加权多模型的权值范围和快速获取加权因子的取值,实现多模型的平滑切换.所提出的充分条件克服了多模型子系统必须稳定的苛刻条件,通过对自主水下机器人多运动模型切换过程的仿真实验表明,依据权值范围所给定的加权因子能够保证加权多模型切换过程中的渐近稳定性.     

Stores clustering using a data mining approach for distributing automotive spare-parts to reduce transportation costs

Clustering of retail stores in a distribution network with specific geographical limits plays an important and effective role in distribution and transportation costs reduction. In this paper, the relevant data and information for an established automotive spare-parts distribution and after-sales services company (ISACO) for a 3-year period have been analyzed. With respect to the diversity and lot size of the available information such as stores location, order, goods, transportation vehicles and road and traffic information, three effecting factors with specific weights have been defined for the similarity function: 1. Euclidean distance, 2. Lot size 3. Order concurrency. Based on these three factors, the similarity function has been examined through 5 steps using the Association Rules principles, where the clustering of the stores is performed using k-means algorithm and similar stores are allocated to the clusters. These steps include: 1. Similarity function based on the Euclidean distances, 2. Similarity function based on the order concurrency, 3. Similarity function based on the combination of the order concurrency and lot size, 4. Similarity function based on the combination of these three factors and 5. Improved similarity function. The above mentioned clustering operation for each 5 cases addressed in data mining have been carried out using R software and the improved combinational function has been chosen as the optimal clustering function. Then, trend of each retail store have been analyzed using the improved combinational function and along with determining the priority of the depot center establishment for every cluster, the appropriate distribution policies have been formulated for every cluster. The obtained results of this study indicate a significant cost reduction (32%) in automotive spare-parts distribution and transportation costs.     

Two-stage updating pheromone for invariant ant colony optimization algorithm

Ant colony optimization (ACO) is a metaheuristic approach for combinatorial optimization problems. With the introduction of hypercube framework, invariance property of ACO algorithms draws more attention. In this paper, we propose a novel two-stage updating pheromone for invariant ant colony optimization (TSIACO) algorithm. Compared with standard ACO algorithms, TSIACO algorithm uses solution order other than solution itself as independent variable for quality function. In addition, the pheromone trail is updated with two stages: in one stage, the first r iterative optimal solutions are employed to enhance search capability, and in another stage, only optimal solution is used to accelerate the speed of convergence. And besides, the pheromone value is limited to an interval. We prove that TSIACO not only has the property of linear transformational invariance but also has translational invariance. We also prove that the pheromone trail can limit to the interval (0, 1]. Computational results on the traveling salesman problem show the effectiveness of TSIACO algorithm.     

非满管电磁流量计权重函数有限元数值分析

采用有限元数值分析法,对长弧形电极非满管电磁流量传感器的权重函数进行了研究,并给出了不同液位下的权重函数分布图谱。计算结果表明,非满管电磁流量传感器的权重函数与管内液体充满度有关,两者呈复杂函数关系。该研究结果为优化非满管电磁流量传感器结构提供了理论依据。     

无线迁移工作流环境中功能片动态装载机制

从无线迁移工作流环境中资源受限的移动设备特性出发,提出一种基于功能片的动态装载机制,以实现大型迁移工作流程序在移动设备上的不降级运行.首先,给出了动态装载单元的定义,包括功能片、说明文档和控制块.控制块确定了功能片的状态;其次,设计并实现了FU的动态装载方案,包括功能片的读入、处理、调度、执行和卸载几个部分;最后,设计并实现了一个移动酒店预订系统来验证其合理性.     

小波神经网络对风力发电机齿轮箱的故障诊断

为研究风力发电机组齿轮箱的故障特性,提高其工作的可靠性,提出采用小波神经网络对齿轮箱的故障进行诊断的方案。该方案采用小波包分析与径向基函数(RBF)神经网络相结合组成小波神经网络,以准确地识别风力发电机组中齿轮箱常见的故障。诊断结果证明了方案的可行性。该方案在风力发电机组齿轮箱故障诊断领域具有良好的实用前景。     

余弦函数型最佳一致逼近多项式

依据最佳一致逼近的基本理论,围绕切比雪夫多项式的特征方程,参照余弦函数的变化图形,建立了余弦函数型最佳一致逼近Cn(x)多项式.@@文中介绍了Cn(x)多项式在被逼近函数y(x)=0条件下依据的微分方程、相关定义、有关性质、数学表式、递推公式;讨论了它与切比雪夫Tn(x)多项式之间的关系及转化;提供了在y(x)≠0条件下Cn(x)多项式转化成c(x)所具有的特征和特点;给出了关于c(x)多项式得以实现的具体算法.应用实例表明,在减少多项式的摆动性、提高逼近精度、增大预测范围方面都有较大的改善和提高.     

YUV空间的彩色图像HDR合成算法

RGB空间的高动态范围(HDR)彩色图像合成算法存在颜色失真和计算耗时的问题。为此,提出一种YUV空间的彩色图像HDR合成算法。利用多幅不同曝光度的普通数字图像,通过计算机高速运算对彩色图像进行HDR合成。实验结果表明,该算法的合成图像质量较高、计算速度较快。     

级联函数的代数免疫性研究

研究级联函数的代数免疫性,级联构造方法是构造具有良好密码学性质布尔函数的重要方法。讨论级联函数 和 的代数免疫性,得到它们代数免疫阶的上下界,并分别给出达到其上界的一个充分条件。与已有的研究相比,该充分条件在实际应用时更容易得到满足,且易于判别。