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结合svd_tls及ekf算法的动态自组织模糊神经网络在动态系统中的应用  [PDF]
李云?
计算机科学 , 2012,
Abstract: 针对如何优化模糊神经网络的规则及如何合理地调整非线性参数及线性参数等问题,提出了将奇异值分解_总体最小二乘法(svd_tls)及扩展卡尔曼滤波(ekf)相结合的动态自组织模糊神经网络(std_dsfnn)。首先给出了stddsfnn的结构及各层的含义;其次,用ekf算法学习非线性参数,svd_tls算法学习线性参数的同时提取重要模糊规则;最后,通过典型的machey-ulass时间序列预测实例验证svd_tls及ekf相结合的动态自组织模糊神经网络(ste_dsfnn),同时与dfnn,anfis及ukf_dfnn相对比,结果表明stedsfnn网络结构更紧凑,具有更好的泛化能力。
应用改进欧拉算法解算磁性目标空间位置参数  [PDF]
卞光浪,翟国君,刘雁春,黄谟涛,欧阳永忠
测绘学报 , 2011,
Abstract: 指出了目前磁性目标探测中常规欧拉方法存在的局限性,提出在欧拉窗口内视地磁场和其它目标干扰异常联合影响为线性变化,将构造指数作为动态变化参数代入欧拉方程一并求解,并利用多元线性回归方法解决了欧拉方程非线性问题。在质量控制方案中,根据构造指数和目标深度变化规律,给出了离散欧拉解滤波措施;采用层次聚类分析方法对滤波后欧拉解进行分类,其思路为基于距离判断准则,对欧拉解进行了初次分类,用检验法判定各簇是否来源于同一总体,以修正初次分类结果,经过淘汰含欧拉解数目较少的簇后,剩余各簇位置参数的重心则对应磁性目标空间位置。通过球体与长方体仿真试验以及实测数据验证表明给定相关阈值参数后,实现了欧拉方法全自动反演,磁性目标空间位置参数具有很高解算精度,噪声对目标平面位置解算结果基本上没有影响,但对深度解算结果存在一定影响。
ON THE SOLVABILITY OF TLS PROBLEM
关于TLS问题的可解性

刘新国
计算数学 , 1992,
Abstract: The total least square (TLS for short) technique is an important method instatistics, nonlinear programming and numerical fittings. In, by using SVD, Goluband Van Loan obtained sufficient conditions for the solvability of the TLS problem.In this paper, the solvability of the TLS problem is discussed completely. Necessaryand sufficient conditions for the solvability are established. Also, a residual expressionis given.
TLS hardening  [PDF]
Emmanuel Dreyfus
Computer Science , 2014,
Abstract: This document presents TLS and how to make it secure enough as of 2014 Spring. Of course all the information given here will rot with time. Protocols known as secure will be cracked and will be replaced with better versions. Fortunately we will see that there are ways to assess the current security of your setup, but this explains why you may have to read further from this document to get the up to date knowledge on TLS security. We will first introduce the TLS protocol and its underlying components: X.509 certificates, ciphers, and protocol versions. Next we will have a look at TLS hardening for web servers, and how to plug various vulnerabilities: CRIME, BREACH, BEAST, session renegotiation, Heartbleed, and others. We will finally see how the know-how acquired on hardening web servers can be used for other protocols and tools such as Dovecot, Sendmail, SquirrelMail, RoundCube, and OpenVPN. We assume you already maintain services that use TLS, and have basic TCP/IP network knowledge. Some information will also be useful for the application developer.
A new convolutional and deconvolutional method
褶积与反褶积的一种计算方法

CHEN Bao-shu,MEI Jin-shun,WANG Run-qiu,
陈宝书

地球物理学进展 , 2009,
Abstract: 应用FFT方法计算实型线性褶积与反褶积问题时,通常需要将线性褶积转化为k=1的循环褶积,因而所得到的计算结果是近似的并且产生较为严重的边界效应问题.本文提出了一种新方法,它通过将线性褶积转化为k=±-1的循环型褶积,然后引入FFT进行计算;在保证不增加计算量的情况下,所得到的实型褶积运算是精确的、反褶积运算中边界效应可以得到较好的改善.
褶积神经网络高分辨率地震反演  [PDF]
张繁昌,刘汉卿,钮学民,代荣获
石油地球物理勘探 , 2014,
Abstract: ?随着地震勘探精细化要求的提高,薄层及横向变化大的复杂储层反演越来越重要.而当前反演方法大多基于褶积模型,分辨率较低.本文提出了基于褶积神经网络的反演方法,该方法完全由数据驱动,不受褶积模型的限制.褶积神经网络具有层状结构,其输入输出之间的映射关系用褶积算子来描述,而非内积算子.基于褶积神经网络结构,本文给出了映射算子的优化算法,并将其应用到地震反演中.应用结果表明,通过褶积神经网络地震反演,可以获得比常规稀疏脉冲反演分辨率更高的地层波阻抗剖面.
TLS Proxies: Friend or Foe?  [PDF]
Mark O'Neill,Scott Ruoti,Kent Seamons,Daniel Zappala
Computer Science , 2014,
Abstract: The use of TLS proxies to intercept encrypted traffic is controversial since the same mechanism can be used for both benevolent purposes, such as protecting against malware, and for malicious purposes, such as identity theft or warrantless government surveillance. To understand the prevalence and uses of these proxies, we build a TLS proxy measurement tool and deploy it via Google AdWords campaigns. We generate 15.2 million certificate tests across two large-scale measurement studies. We find that 1 in 250 TLS connections are TLS-proxied. The majority of these proxies appear to be benevolent, however we identify over 3,600 cases where eight malware products are using this technology nefariously. We also find numerous instances of negligent, duplicitous, and suspicious behavior, some of which degrade security for users without their knowledge. Distinguishing these types of practices is challenging in practice, indicating a need for transparency and user awareness.
The Extraordinary SVD  [PDF]
Carla D. Martin,Mason A. Porter
Physics , 2011,
Abstract: The singular value decomposition (SVD) is a popular matrix factorization that has been used widely in applications ever since an efficient algorithm for its computation was developed in the 1970s. In recent years, the SVD has become even more prominent due to a surge in applications and increased computational memory and speed. To illustrate the vitality of the SVD in data analysis, we highlight three of its lesser-known yet fascinating applications: the SVD can be used to characterize political positions of Congressmen, measure the growth rate of crystals in igneous rock, and examine entanglement in quantum computation. We also discuss higher-dimensional generalizations of the SVD, which have become increasingly crucial with the newfound wealth of multidimensional data and have launched new research initiatives in both theoretical and applied mathematics. With its bountiful theory and applications, the SVD is truly extraordinary.
极小熵褶积滤波算子的渐近性态  [PDF]
王承曙
计算数学 , 1981,
Abstract: 极小熵褶积滤波(简称MED)是近年来为提高地震勘探数字信号中的地震脉冲分辨率而提出的一种新的滤波方法.它是在时间域上处理滤波问题,其基本思想是以信号熵极小为判据,找一个线性——时不变滤波算子(即褶积滤波算子),以使系统输出信号最大限度地尖峰化,亦即输出为最简单信号.
关于TLS问题  [PDF]
魏木生,朱超
计算数学 , 2002,
Abstract: 1.引言考虑观测线性系统AX=B,(1.1a)其中A∈Cm×n,B∈Cm×d(本文通篇假设m≥n+d),分别是精确但不可观测的A0∈Cm×n,B0∈Cm×d的近似,即精确线性系统是A0X=B0.(1.1b)Golub和VanLoan于1980年提出的总体最小二乘问题(以下简称TLS问题)就是求解线性系统AX=B(1.2)
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