基于信息熵的支持向量数据描述分类

针对现有的支持向量数据描述(SVDD)在解决分类问题时通常存在盲目性和有偏性,在研究信息熵和SVDD分类理论的基础上,提出了改进两类分类问题的E-SVDD算法。首先对两类样本数据分别求出其熵值;然后根据熵值大小决定将哪类放在球内;最后结合两类样本容量以及各自的熵值所提供的分布信息,对SVDD算法中的C值重新进行定义。采用该算法对人工样本集和UCI数据集进行实验,实验结果验证了算法的可行性和有效性。     

芘功能化单分子层荧光薄膜荧光猝灭机理的分子动力学研究

实验证明,芘功能化单分子层荧光薄膜的荧光能被溶液中的硝基苯显著猝灭,为了找到猝灭的根本原因,本文采用分子动力学模拟方法来研究猝灭的机理.模拟结果表明,该薄膜在真空环境中,一对芘环中心的距离分布在(4～10)A之间,且主要是在5.3 A左右,该距离正适合于形成芘激子.当把硝基苯分子加入到该薄膜中时,我们发现芘分子在这一距...     

基于变长元组的文件类型识别算法

快速准确地判断文件实体的真实类型对保护计算机信息安全具有重要意义。通过分析现有基于二进制内容的文件类型识别算法中存在的问题,提出采用变长元组描述文件的统计特征,并结合结构化文件中元组的分散度、稳定度以及条件广泛度设计出一种特征评估函数,从而更加准确地选取有效的特征。该算法不依靠特定文件类型的结构和关键标识,适用范围更为广泛。实验表明该算法能有效提高文件类型识别的查准率和查全率。     

基于Real Adaboost的肤色分割方法

提出了一种基于Real AdaBoost算法构造的肤色置信度分类器及动态阈值相结合的肤色分割方法。根据肤色在YCrCb色度空间的聚类性,通过大量肤色和非肤色样本用Real AdaBoost训练一族查找表(LUT)型圆形弱分类器,组成一个能输出连续置信度的强分类器,利用肤色强分类器计算图像中像素的肤色相似度,最后用大津法确定阈值对肤色相似图进行二值分割。实验表明,该方法能较好地描述肤色分布,误检率低,鲁棒性好。     

燃气报警器报警点漂移模型研究

根据燃气报警器报警点年漂移试验 ,探讨了报警点漂移原因及改进措施 ,建立了报警点漂移的正态分布模型 ,并经用 χ2 检验法进行了检验。依据行业标准CJ- 30 5 7,结合燃气报警器的加严试验结果 ,提出了报警器最佳标定点。     

抑制NACK的定时器设置方法

FEC can be combined with ARQ to achieve large scalable reliable mutlicast. The NACK im-plosion is a major problem in receiver-initiated reliable multicast when a large, number of receivers sendsNACK to the sender. The method that receivers send NACK to the sender based on timer can avoid theNACK implosion. We propose a method to set timers. The method of time divided unequally and basedon exponential distribution to set timers has the better perfornance. By analysis for up to 10^10 receivers,we show the NACK implosion is avoided and feedback delay due to timers is low.     

Gamma mixture models for target recognition

This paper considers a mixture model approach to automatic target recognition using high-resolution radar measurements. The mixture model approach is motivated from several perspectives including requirements that the target classifier is robust to uncertainty in amplitude scaling, rotation and translation of the target. Estimation of the model parameters is achieved using the expectation-maximisation (EM) algorithm. Gamma mixtures are introduced and the re-estimation equations derived. The models are applied to the classification of high-resolution radar range profiles of ships and results compared with a previously published self-organising map approach.     

分布存储并行机上的自动数据布局优化模型

在分布式并行机上,数据布局的质量极大的影响着应用程序的执行性能,以往的研究一般将自动数据布局优化问题近似分解为数据对准优化和数据分布优化两步来解决,且对两者的结合只研究了一维的情况,在相关研究工作的基础上,在多维情况下将数据对准优化和数据分布优化结合在一个模型当中,提出了一个数据对准优化与数据分布优化统一的多维静态数据布局模型,避免了采用启发式策略,从而更加精确地描述了自动数据布局优化问题,同时给     

PDUIMS--基于持久存储的用户界面管理系统的设计与应用

用户界面作为软件系统的重要组成部分,在软件整个生命周期中具有独特的地位。软件质量控制的核心在于用户界面的有效、可扩展、高适应度的管理、常规的界面管理位于源码一级,对于大规模企业级应用将带来许多弊端文中介绍了一个利用动态加载和持久存储实现的面向商务处理的用户界面管理系统ＰＤＵＩＭＳ,该系统通过功能描述数据表存储用户界面实现了集中统一的数据库工程化界面管理和发布,对于应用语义提供了分离机制实例表明了该     

An Estimation of Complexity and Computational Costs for Vertical Block-Cyclic Distributed Parallel LU Factorization

The Vertical Block–cyclic Distributed Parallel LU Factorization Method (VBPLU) is effectively processed on a distributed memory parallel computer. VBPLU is based on the two techniques, the block algorithm and the aggregation of communications. Since startup time dominates the data communication and the aggregation reduces communication isssues, the total performance has been much improved. Furthermore this method uses long vectors so that it is also advantageous on vector processors. In this paper, we have constructed a modeling of VBPLU using a simplified LogGP model with analytical formulae, and estimated accurately the computational cost taking into account load distributions caused by data layout and process mapping. Some knowledge for optimization of block algorithm has been obtained. Our estimations have been verified through numerical experiments on three different distributed memory parallel computers.