449 research outputs found
Industrial Internet of Things, Big Data, and Artificial Intelligence in the Smart Factory: a survey and perspective
International audienceThanks to the rapid development and applications of advanced technologies, we are experiencing the fourth industrial revolution, or Industry 4.0, which is a revolution towards smart manufacturing. The wide use of cyber physical systems and Internet of Things leads to the era of Big Data in industrial manufacturing. Artificial Intelligence algorithms emerge as powerful analytics tools to process and analyze the Big Data. These advanced technologies result in the introduction of a new concept in the Industry 4.0: the smart Factory. In order to fully understand this new concept in the context of the Industry 4.0, this paper provides a survey on the key components of a smart factory and the link between them, including the Industrial Internet of Things, Big Data and Artificial Intelligence. Several studies and techniques that are used to enable smart manufacturing are reviewed. Finally, we discuss some perspectives for further researches
A Bayesian ARMA-GARCH EWMA monitoring scheme for long run : a case study on monitoring the USD/ZAR exchange rate
Statistical process monitoring (SPM) offers an important toolkit used to monitor the stability of a process to improve the quality of outputs and/or services. More often, the design of control charts requires the estimation of the probability density function that involves selecting a common distribution that facilitates the estimation of the process parameters. The Bayesian approach is one of the most efficient techniques used in such instances. It incorporates informative and non-informative priors, i.e., uses information on past data and charting structures, to estimate parameters more efficiently than classical approaches. Bayesian approaches reduce the total expected cost over a finite horizon or the long-run expected average cost. This paper introduces a new Bayesian exponentially weighted moving average (EWMA) monitoring scheme for long runs based on an ARMA-GARCH model. The properties of the new monitoring scheme are investigated in terms of the run-length distribution. A case study on monitoring the USD to ZAR exchange rate is provided using the proposed Bayesian ARMA-GARCH EWMA monitoring scheme.The South African National Research Foundation (NRF), UCDP and the Research Development Programme at the University of Pretoria, Department of Research and Innovation (DRI).https://www.tandfonline.com/loi/lqen202024-07-20hj2024StatisticsSDG-08:Decent work and economic growt
Estimating process capability index Cpm using a bootstrap sequential sampling procedure
Construction of a confidence interval for process capability index CPM is often based on a normal approximation with fixed sample size. In this article, we describe a different approach in constructing a fixed-width confidence interval for process capability index CPM with a preassigned accuracy by using a combination of bootstrap and sequential sampling schemes. The optimal sample size required to achieve a preassigned confidence level is obtained using both two-stage and modified two-stage sequential procedures. The procedure developed is also validated using an extensive simulation study.<br /
Guaranteed Conditional Performance of Control Charts via Bootstrap Methods
To use control charts in practice, the in-control state usually has to be
estimated. This estimation has a detrimental effect on the performance of
control charts, which is often measured for example by the false alarm
probability or the average run length. We suggest an adjustment of the
monitoring schemes to overcome these problems. It guarantees, with a certain
probability, a conditional performance given the estimated in-control state.
The suggested method is based on bootstrapping the data used to estimate the
in-control state. The method applies to different types of control charts, and
also works with charts based on regression models, survival models, etc. If a
nonparametric bootstrap is used, the method is robust to model errors. We show
large sample properties of the adjustment. The usefulness of our approach is
demonstrated through simulation studies.Comment: 21 pages, 5 figure
Recent developments of control charts and identification of big data sources and future trends of current research
Control charts are one of the principal tools to monitor dynamic processes with the aim of rapid identification of changes in the behaviour of these processes. Such changes are usually associated with a move from an in-control condition to an out-of-control condition. The paper briefly reviews the historical origins and includes examples of recent developments, focussing on their use in fields different from the industrial applications in which they were initially derived and often employed. It also focusses on cases which depart from the commonly used Gaussian assumption and then considers potential effects of the big data revolution on future uses. A bibliometric analysis is also presented to identify distinct groups of research themes, including emerging and underdeveloped areas, which are hence potential topics for future research
Monitoring Capability Indice CM using EWMA
International audienc
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