An economic model including the labor resource and the process stage configuration is proposed to design X¯ charts allowing for all the design parameters to be varied in an adaptive way. A random shift size is considered during the economic design selection. The results obtained for a...

On-line monitoring of quality characteristics is essential to limit scrap and rework costs due to bad quality in a manufacturing process. In several manufacturing environments, during production process data can be massively collected with high sampling rates and tight sampling frequencies. As a...

The Hotelling’s <InlineEquation ID="IEq4"> <EquationSource Format="TEX">$$\textit{T}^{2 }$$</EquationSource> <EquationSource Format="MATHML"> <math xmlns:xlink="http://www.w3.org/1999/xlink"> <msup> <mi mathvariant="italic">T</mi> <mn>2</mn> </msup> </math> </EquationSource> </InlineEquation>control chart with variable parameters (VP <InlineEquation ID="IEq5"> <EquationSource Format="TEX">$$T^{2})$$</EquationSource> <EquationSource Format="MATHML"> <math xmlns:xlink="http://www.w3.org/1999/xlink"> <mrow> <msup> <mi>T</mi> <mn>2</mn> </msup> <mrow> <mo>)</mo> </mrow> </mrow> </math> </EquationSource> </InlineEquation> has been shown to have better statistical performance than other adaptive control schemes in detecting small to moderate process mean shifts. In this paper, we investigate the...</equationsource></equationsource></inlineequation></equationsource></equationsource></inlineequation>

On-line monitoring of process variability is strategic to achieve high standards of quality and maintain at acceptable levels the number of nonconforming items. Shewhart control charts are the simplest Statistical Process Control (SPC) procedure to achieve this goal. An efficient implementation...

Often the manufacturing and the inspection workstations in a manufacturing process can coincide: thus, in these workstations the statistical process control (SPC) procedure of collecting sample statistics related to a critical-to-quality parameter is a task required to be done by the same worker...

We consider a dynamic capacity reallocation scheme in a logically fully-connected telecommunications network. We show that the problem of optimal capacity allocation can be solved in a distributed manner, an essential feature of such a scheme. Our continuous-capacity reallocation scheme can be...

Wind power time series usually show complex dynamics mainly due to non-linearities related to the wind physics and the power transformation process in wind farms. This article provides an approach to the incorporation of observed local variables (wind speed and direction) to model some of these...

In this paper, the stellar pulsation theory is reformulated following an irreversible thermodynamic approach (Lavenda, Thermodynamics of Irreversible Processes, Denver, New York, 1993). A general stability criterion and a thermodynamic Langrangian for the pulsating star problem are obtained...

This paper discusses the mean stationarity of real exchange rates by using new time series methods and new tests. The question whether the real exchange rates have a unit root or are level reverting is set in the general and flexible framework of fractionally integrated processes. The...

This paper presents an economic design of X control charts with variable sample sizes, variable sampling intervals, and variable control limits. The sample size n, the sampling interval h, and the control limit coefficient k vary between minimum and maximum values, tightening or relaxing the...