Banca de QUALIFICAÇÃO: ELIAS JEFERSON DE MELO SILVA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : ELIAS JEFERSON DE MELO SILVA
DATA : 12/04/2018
HORA: 09:00
LOCAL: Sala 222- CTEC
TÍTULO:

Comparative study of the performance of EWMA control charts using the GMTD model for autocorrelated processes.

PALAVRAS-CHAVES:

Autocorrelation; ARL; EWMA; GMTD; Quality; Simulation

PÁGINAS: 40
GRANDE ÁREA: Engenharias
ÁREA: Engenharia de Produção
RESUMO:

Statistical quality control is one of the most important areas of knowledge in quality engineering. Its main objective is the systematic reduction of the variability in the characteristics of the product or process. One of the ways to analyze these characteristics is through the control charts, which allows monitoring of the process. However, some assumptions are necessary for its use, as is the independence between observations. However, in practice, many processes do not fulfill this assumption and end up generating an autocorrelated process. This autocorrelation, if not noticed, can generate an increase in alarm numbers, thus stopping the process several times and leading to an increase in operating costs. Standard control graphs, in general, do not include the calculation of autocorrelation, however, through the developed research, adjustments can be found to such graphs that allow to deal with the autocorrelation. The graph highlighted in this paper is the exponentially weighted moving average, or simply EWMA, as it is an ideal graph to monitor small shifts in the process. Thus, in this study we intend to compare the performance of adjustments found in the literature, this performance comparison will be done by means of the average length of the sequence, or ARL, to the EWMA graph autocorrelated with the model GMTD, which model has a good performance to linear and non-linear behavioural series. It is still intended to search for real data that have autocorrelation and simulated data computationally. At the end of this study we intend to see which of the adjustments to the EWMA or GMTD model is more and more to deal with the most diverse situations of autocorrelation.

MEMBROS DA BANCA:
Externo ao Programa - 1217007 - ANDRE LUIS SANTOS DE PINHO
Presidente - 1218831 - CARLA ALMEIDA VIVACQUA
Interno - 4859773 - RICARDO PIRES DE SOUZA