面向TSP求解的混合蚁群算法

针对蚁群算法的早熟和停滞等现象,将免疫算法机制引入蚁群算法,提出用于TSP求解的混合算法。该算法具有蚁群算法的自适应反馈机理、收敛速度快和免疫算法操作算子简单和维持种群多样性、防止种群退化等特性。从算法解的质量与效率方面与基本蚁群算法和免疫算法进行比较,结果表明融合免疫机制的蚁群算法性能显著提高,也为解决其他组合优化问题提供一个新的思路。     

微球探针制备工艺的优化

为了解决现有激光微球探针加工技术中存在的探针尖端微球球心偏离针杆中轴线的问题,提出了一个两步法加工策略.以CO2激光光束为热源,对探针针杆尖端进行加热,使针杆尖端受热融化产生微球.然后将带有微球的探针针杆绕其中轴线旋转180°,再使用CO2激光光束辐照带有微球的探针尖端,对尖端微球偏移量进行补偿.实验结果表明:采用“熔球-旋转再熔球”的两步法加工策略,能明显降低探针尖端微球相对于针杆的弯曲程度,缩小探针尖端球形球心和针杆中心线的偏移距离.     

基于中国剩余定理的群签名改进方案

自陈泽文首次提出基于中国剩余定理的群签名后,已出现不少对其改进的方案,但仍未有方案在不使用第三方辅助签名或验证的情况下实现非关联性。针对这一问题,提出了一个基于中国剩余定理的群签名改进方案,通过结合子集覆盖框架中完备子树的方法来实现上述非关联性,以满足群成员安全、快速的加入和撤销,而无需改变其他成员私钥。该方案还实现了防权威陷害攻击。最后对其安全性和效率进行分析,并与现有方案进行对比,结果表明,所提方案具有一定的优势。     

有监督核化邻域投影分析算法

通过将鉴别邻域嵌入分析算法扩展到非线性场景,提出了一种有监督核化邻域投影分析算法。该算法在目标函数中引入类别标签和线性投影矩阵,并利用核函数处理非线性数据。通过两种不同策略优化目标函数,可将该算法进一步细分为有监督核化邻域投影分析算法一及有监督核化邻域投影分析算法二。其中,在有监督核化邻域投影分析算法一中应用拉普拉斯搜索方向达到了较快的收敛速度并降低了计算复杂度。实验结果表明,所提算法对于复杂的数据流形具有较高的识别率,且与鉴别邻域嵌入分析等相关算法相比在有效性和鲁棒性方面的表现更为出色。     

一种不确定RFID数据流清洗策略

原始RFID数据流含有大量噪声且具有不确定性,必须在使用之前对其进行数据清洗,而清洗策略是清洗质量的保证。提出一种适合不确定RFID数据流的清洗策略。该清洗策略引入了最大熵原理,对待清洗的RFID元组的特征属性进行权重选择,并根据清洗节点的时间消耗以及误差进行清洗成本分析,决策出最佳的清洗方法。仿真实验结果表明,该清洗策略提高了不确定RFID数据流的清洗效率与精度。     

基于身份加密的装备密钥分布式生成算法

为解决身份加密体制中单一密钥生成中心易遭受攻击的问题,借鉴网络中心战“去中心化”的思想,针对Lewko-Waters身份加密协议,提出了一种分布式密钥生成算法。在算法中,主密钥由密钥生成中心和密钥隐私中心共同掌握,用户密钥在密钥生成中心监管下由分布于网络中的各密钥隐私中心共同生成,有利于增强Lewko-Waters协议密钥管理体系的抗毁性、鲁棒性。最后,在标准模型中证明了该方案在选择明文攻击下的密文不可区分性,并进行了算法性能比较分析。     

An interactive approach based on a discrete differential evolution algorithm for a class of integer bilevel programming problems

This paper presents an interactive approach based on a discrete differential evolution algorithm to solve a class of integer bilevel programming problems, in which integer decision variables are controlled by an upper-level decision maker and real-value or continuous decision variables are controlled by a lower-level decision maker. Using the Karush--Kuhn–Tucker optimality conditions in the lower-level programming, the original discrete bilevel formulation can be converted into a discrete single-level nonlinear programming problem with the complementarity constraints, and then the smoothing technique is applied to deal with the complementarity constraints. Finally, a discrete single-level nonlinear programming problem is obtained, and solved by an interactive approach. In each iteration, for each given upper-level discrete variable, a system of nonlinear equations including the lower-level variables and Lagrange multipliers is solved first, and then a discrete nonlinear programming problem only with inequality constraints is handled by using a discrete differential evolution algorithm. Simulation results show the effectiveness of the proposed approach.     

An implicit skeleton-based method for the geometry reconstruction of vasculatures

Due to the high complexity of vascular system network, the geometry reconstruction of vasculatures from raw medical datasets remains a very challenging task. In this paper, we present a novel skeleton-based method for the geometry reconstruction of vascular structures from standard 3D medical datasets. With the proposed techniques, the geometry of vascular structures with high level of smoothness and accuracy can be reconstructed from the raw medical datasets. The experimental results and comparison with other techniques demonstrate that our method can achieve faithful and smooth vascular structures. In addition, quantitative validation has been conducted to evaluate the accuracy and smoothness of the reconstructed vessel geometry based on the proposed method.     

Image compression-encryption scheme combining 2D compressive sensing with discrete fractional random transform

Multimedia Tools and Applications - Most of the existing image encryption algorithms based on compressive sensing are too complex to operate. An image compression-encryption scheme with simple...