In some statistical process control applications, the quality of the product is characterized by thecombination of both correlated variable and attributes quality characteristics. In this paper, we propose anovel control scheme based on the combination of two multi-layer perceptron neural networks forsimultaneous monitoring of mean vector as well as the covariance matrix in multivariate-attribu...

The principal function of a control chart is to help management distinguish different sources of variation in a process. Control charts are widely used as a graphical tool to monitor a process in order to improve the quality of the product. Chen and Hsieh (2007) have designed a T2 control chart using a Variable Sampling Size and Control limits (V SSC) scheme. They have shown that using the V SSC...

Fuzzy control charts are proposed to solve the problem that traditional cannot be applied fuzzy quality characteristics. First, characteristics converted representative statistics, which mode transformation, level midrange transformation and median transformation. Control designed based on Poisson distribution. Second, effects of different statistics analysed. Direct Charts avoid some informati...

The production and updating of paper chart is always the theme to the guarantee and improvement of hydrographic chart, in which the quality detection and control is the key to consider. At present, the production of paper chart has already achieved digital mapping with the widespread application of computer technology in the field of marine surveying and mapping. However, it is difficult to ens...

Traditional statistical process control charts used to monitor key process variables are based on the assumption that measurements are independent and identically distributed about a target value. In practice they are not and often are actually correlated. Reliance on univariate charts can lead to misleading conclusions. This paper addresses the methods for improving the quality of industrial p...

Quality control charts indicate out of control conditions if any nonrandom pattern of the points is observed or any point is plotted beyond the control limits. Nonrandom patterns of Shewhart control charts are tested with sensitizing rules. When the processes are defined with fuzzy set theory, traditional sensitizing rules are insufficient for defining all out of control conditions. This is due...

Control charts are one of the most important tools in statistical process control that lead to improve quality processes and ensure required quality levels. In traditional control charts, all data should be exactly known, whereas there are many quality characteristics that cannot be expressed in numerical scale, such as characteristics for appearance, softness, and color. Fuzzy sets theory is p...

In this paper, we proposed a new quality control chart for the sample mean based on a cost free and anti wasting sampling unit’s scheme known by the folded ranked set sampling (FRSS). The new control charts were compared with the classical control charts when the data obtained by using simple random sampling (SRS) and ranked set sampling (RSS). A simulation study showed that the FRSS based cont...