نتایج جستجو برای: fuzzy ewma statistic

تعداد نتایج: 109634  

Journal: :Computational Statistics & Data Analysis 2011
M. A. Graham Subha Chakraborti S. W. Human

Nonparametric control charts can provide a robust alternative in practice to the data analyst when there is a lack of knowledge about the underlying distribution. A nonparametric exponentially weighted moving average (NPEWMA) control chart combines the advantages of a nonparametric control chart with the better shift detection properties of a traditional EWMA chart. A NPEWMA chart for the media...

Journal: :IEEE Trans. Reliability 2003
Nong Ye Sean Vilbert Qiang Chen

Reliability and quality of service from information systems has been threatened by cyber intrusions. To protect information systems from intrusions and thus assure reliability and quality of service, it is highly desirable to develop techniques that detect intrusions. Many intrusions manifest in anomalous changes in intensity of events occurring in information systems. In this study, we apply, ...

2010
Lianjie SHU Wei JIANG

The exponentially weighted moving average (EWMA) control chart has been widely studied as a tool for monitoring normal processes due to its simplicity and efficiency. However, relatively little attention has been paid to EWMA charts for monitoring Poisson processes. This paper extends EWMA charts to Poisson processes with emphasis on quick detection of increases in Poisson rate. Both cases with...

One-way analysis of covariance is a popular and common statisticalmethod, wherein the equality of the means of several random variables whichhave a linear relationship with a random mathematical variable, is tested. Inthis study, a method is presented to improve the one-way analysis of covari-ance when there is an uncertainty in accepting the statistical hypotheses. Themethod deals with a fuzzy...

Journal: :Quality and Reliability Eng. Int. 2015
Saddam Akber Abbasi Muhammad Riaz Arden Miller Shabbir Ahmad Hafiz Zafar Nazir

Process monitoring through control charts is a quite popular practice in statistical process control. This study is planned for monitoring the process dispersion parameter using exponentially weighted moving average (EWMA) control chart scheme. Most of the EWMA dispersion charts that have been proposed are based on the assumption that the parent distribution of the quality characteristic is nor...

2002
Vinay A. Mahadik Xiaoyong Wu Douglas S. Reeves

In this paper, we describe a method of detecting denial of Quality of Service attacks on DiffServ networks. Our approach focusses on real time and quick detection, scalability to large networks, and a negligible false alarm generation rate. Sensors sample QoS parameters like bit rate, packet dropping rate, and jitter of specific Virtual Leased Line (VLL) flows at predefined strategic points in ...

Journal: :International Journal of Geographical Information Science 2003
Alex Hagen

For the evaluation of results from remote sensing and high-resolution spatial models it is often necessary to assess the similarity of sets of maps. This paper describes a method to compare raster maps of categorical data. The method applies fuzzy set theory and involves both fuzziness of location and fuzziness of category. The fuzzy comparison yields a map, which specifies for each cell the de...

Journal: :Clinical chemistry 1997
A S Neubauer

A quality-control chart based on exponentially weighted moving averages (EWMA) has, in the past few years, become a popular tool for controlling inaccuracy in industrial quality control. In this paper, I explain the principles of this technique, present some numerical examples, and by computer simulation compare EWMA with other control charts currently used in clinical chemistry. The EWMA chart...

Journal: :Mathematics 2021

A multivariate control chart is proposed to detect changes in the process dispersion of multiple correlated quality characteristics. We focus on individual observations, where we monitor data vector-by-vector rather than (rational) subgroups. The developed by applying logarithm diagonal elements estimated covariance matrix. Then, this vector incorporated an exponentially weighted moving average...

2015
S Gogoi

In this paper, a comparative study of performance of some parametric and nonparametric EWMA control charts for detecting the process mean shift is considered. In section 2, we briefly describe each of the various EWMA models that are taken into account in our present study, Viz. the Parametric X -EWMA and Nonparametric Grouped Signed Rank (GSR)-EWMA, for the purpose of comparative study. In Sec...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید