基于序列分析的僵尸网络检测模型

现有的IRC botnet检测技术不适合控制命令交互不频繁的botnet检测。为了实现小规模隐秘僵尸网络的检测,提出了一种基于序列分析的僵尸网络检测模型,对现有的被动检测技术进行补充。讨论了几种探测技术和检测算法,根据客户端响应类型选择检测算法,分析了平均检测轮数,只须观察少量的命令控制交互,能够对单个或多个IRC僵尸主机进行检测。实验结果表明,在保证误报率和漏报率的前提下该方法能在预定检测轮数内完成判定。     

Discussion

In this discussion, we give a short overview of some of the uses of artificial neural networks in practice. This is not intended to be an exhaustive list, but it includes some widely used industrial examples with which we are familiar. From our experience, we also attempt to point out why they are used and what the relative advantages and disadvantages of using a neural network over a traditional statistical method might be.     

A decision theoretic approach to change point estimation for binomial CUSUM control charts

Detecting when the process has changed is a classical problem in sequential analysis and is an important practical issue in statistical process control. This article is concerned about the binomial cumulative sum (CUSUM) control chart, which is extensively applied to industrial process control, health care, public health surveillance, and other fields. For the binomial CUSUM, a maximum likelihood estimator has been proposed to estimate the change point. In our article, following a decision theoretic approach, we develop a new estimator that aims to improve the existing methods. For interval estimation, we propose a parametric bootstrap procedure to construct the confidence set of the change point. We compare our proposed method with the maximum likelihood estimator and Page's last zero estimator in terms of mean squared error by simulations. We find that the proposed method gives more unbiased and robust results than the existing procedures under various parameter designs. We analyze jewelry manufacturing data for illustration.     

Some remarks on minimax sequential tests for stationary ornstein–uhilenbeck processes

In this paper sequential tests of one sided hypotheses H₁ : μ ≤ μ₀ and H₂ : μ > μ₀ for the velocity parameter of a stationary Ornstein-Uhlenbeck process(OUP) are discussed. When the variance parameter of the OUP is known the results obtained here complement a recent work of Roters (1991) by proving the existence of minimax sequential tests under concave and symmetric (about μ₀) loss l(μ)with l(μ₀) > 0 and linear costs of observation. For unkown variance parameter minimax sequential tests are derived for all loss functions discussed here and in the above mentioned paper.     

Intercomparison of the Realizations of the ITS-90 from 83.8058 K to 692.677 K among European NMIs

The EUROMET.T-K3 comparison is the regional extension of CCT-K3. The comparison involved the six European national metrology institutes (NMIs) previously involved in CCT-K3 (LNE-INM/CNAM, SMU, INRiM, NMi-VSL, NPL, PTB) and 18 additional European national laboratories. The comparison was divided into five different loops, each coordinated by a co-pilot chosen from the laboratories having participated in the CCT-K3 comparison. LNE-INM/CNAM played the role of pilot in linking the five loops. In each loop, an artifact in the form of a standard platinum resistance thermometer (SPRT, 25 Ω) was circulated among the participating laboratories. To have sufficient information about the possible drift of the SPRTs, the co-pilots performed a calibration over the full temperature range at the beginning and at the end of the loop. A EUROMET reference value (ERV), taking into account the whole comparison, was defined, and the differences (T _Lab − T _ERV) were calculated with the associated uncertainties. The method for establishing the link between the participants in CCT-K3 and in EUROMET.T-K3 is described. Institut National de Métrologie (BNM-INM/CNAM at the time of the comparison, LNE-INM/CNAM since 1 January 2005), Paris, France.     

故障检测与诊断的SPRT方法及其修正

本文简单介绍了基于对新息序列处理而进行故障检测与诊断的 SPRT 法,然后针对这种方法有检测迟延的不足,给出了均值和方差都发生变化的修正的 SPRT 检测与诊断方法,并做了一些分析.     

自滚切刀具及其工作角度的算法

本文对决定自滚切刀具切削性能的最重要参数──安装刃倾角λｓ进行了分析，推导了工作角度（γｏｅ、αｏｅ、λｓｅ）的近似算法和精确算法．并对两种算法的结果进行了对比，指出了近似算法的适用范围。     

计量标准期间核查方法的建立与运用

从期间核查对实验室计量标准的重要性、必要性和实际应用情况出发,针对对计量标准重复性和稳定性的要求,提出了一种建立期间核查控制图的计量标准的期间核查方法,并以标准铂电阻温度计为核查对象阐明了对控制图的运用。该核查方法可供计量标准管理者、使用者进行参考,确保对计量标准的计量过程受控的质量管理。     

Optimality Of sequential prorability ratio tests for a class of continuous parameter stochastic processes

For a wide class of stochastic processes including processes belonging to the curved exponential families, it is proved that Wald SPRT is optimal in the sense of minimizing the expectations of increasing processes associated with the stochastic process. The increasing processes are given by the Doob-Meyer decompositions of the log-probability ratio under the two hypotheses.     

基于ARMA模型的序贯概率比改进算法

针对常规的序贯概率比检验方法（sequenceprobabilityratiotest,SPRT）在故障检测时存在的较大时间延迟,本文提出一种通过对序贯概率比时间序列运用自回归滑动平均（auto—regressivemovingaverage,ARMA）模型,建立预测反馈控制机制的SPRT改进算法。该算法的核心思想是根...