C-control chart assumes that process nonconformities follow a Poisson distribution. In actuality, however, this Poisson distribution does not always occur. A process control for semiconductor based on a Poisson distribution always underestimates the true average amount of nonconformities and the process variance. Quality is described more accurately if a compound Poisson process is used for pro...

Correlated binary data are encountered in many areas of medical research, system reliability and quality control. For monitoring failures rates in such situations, simultaneous bivariate cumulative sum (CUSUM) charts with the addition of secondary control limits are proposed. Using an approach based on a Markov chain model, the run length properties of such a monitoring scheme can be determined...

In this paper CUSUM control charts for zero-truncated negative binomial distribution (ZTNBD) and zero-truncated geometric distribution (ZTGD) are constructed. Average run length (ARL) is studied for different values of the parameters of both the distributions. The method of Johnson (1961) is used for constructing the CUSUM chart.

This work presents a comparative study of the performance of the cumulative sum (CuSum), as well as the exponentially weighted moving average (EWMA) control charts. The objective of this research is to verify when CuSum and EWMA control charts do the best control region, in order to detect small changes in the process average. Starting from the data of a productive process, several series were ...

Introduction: One major problem in analyzing epidemic data is the lack of data and high dependency among the available data, which is due to the fact that the epidemic process is not directly observable. Methods: One method for epidemic data analysis to estimate the desired epidemic parameters, such as disease transmission rate and recovery rate, is data ...

The reliability data is getting used to monitor and improve the quality of products or services. Nowadays, most of products or services are the results of processes with dependent stages referred to as multi-stage process. In these processes, the quality characteristics are affected by the quality characteristics in the previous stages, called as cascade property. In some cases, it is not possi...

Understanding and modelling packet loss in the Internet is especially relevant for the design and analysis of delay-sensitive multimedia applications. In this paper, we present analysis of hours of endto-end unicast and multicast packet loss measurement. From these we selected hours of stationary traces for further analysis. We consider the dependence as seen in the autocorrelation function of ...

In this Paper, we worked on the modeling of packet loss within MPLS environment. The research exploited real data from a real network running MPLS as its core switching. The data were obtained from 6 nodes, each node participated with 6 hours of traffic segments used as data set, all nodes formed 36 hours as testing data. Each dataset was divided into one-hour segment, each segment loss and no-...

For an improved monitoring of process parameters, it is generally desirable to have ef?cient designs of control charting structures. The addition of Shewhart control limits to the cumulative sum (CUSUM) control chart is a simple monitoring scheme sensitive to wide range of mean shifts. To improve the detection ability of the combined Shewhart–CUSUM control chart to off-target processes, we deve...

I N recent years, statistical process control (SPC) for autocorrelated processes has received a great deal of attention, due in part to the increasing prevalence of autocorrelation in process inspection data. With improvements in measurement and data collection technology, processes can be sampled at higher rates, which often leads to data autocorrelation. It is well known that the run length p...