Читать книгу Electronics in Advanced Research Industries - Alessandro Massaro - Страница 25

Process mapping represents a very important procedure to follow for quality control. All production data provided by sensors, and also results of the image processing tools, are in general stored in DB systems and mapped by diagrams such as fishbone diagrams, p‐charts, the Plan‐Do‐Check‐Act (PDCA) cycle, and by XmR charts, thus improving the quality check during the time. The PDCA cycle, also known as the Deming cycle diagram, is a four‐step iterative management method used for the control and continuous improvement of processes and products. Steps in PDCA include:

 The Plan concerning the occurring variations.

 The actions to Do and to be controlled.

 The Check of the executions by validating expected results.

 The Act involving all the activities about the process, the standardization and stability, and improving the existing procedure.

The XmR chart, through the upper and lower control limits, provides the limits of an industrial production process mapping at the same time production results. As a further diagram to adopt for process mapping, a fishbone diagram (Ishikawa diagram) is a cause‐and‐effect approach able to track imperfections, variations, defects, or failures. This diagram is structured as a fish's skeleton with the problem at its head and the causes for the problem following the fish bones. In order to also predict defects or production failures, big data systems facilitate the analysis of the historical data. Big data systems implement NoSQL technology based on the following main categories:

 key‐value distributed

 document oriented

 column oriented

 graph oriented

However, some NoSQL DBMSs may have features that belong to more than one of these categories. Some common big data systems are Cassandra, MongoDB, and Hbase.