Identification of the assignable causes of process variability and the restriction and elimination of their influence are the main goals of statistical process control (SPC). Identification of these causes is associated with so called tests for special causes or runs tests. From the time of the formulation of the first set of such rules (Western Electric rules) several different...

It records one or more variables with respect to time. It is a X-t recorder. A strip chart recorder consists of: 1. A long roll of graph paper moving vertically. 2. A system for driving a paper at some selected speed. A speed selector switch is generally provided. Chart speed of 1-100 m/s are usually used. 3. A stylus driving system which moves the stylus in a near exact replica or analog of th...

The Pareto chart is a bar chart of frequencies sorted by frequency. The most popular incarnation of the chart puts the highest bars on the left and includes a line showing the scores produced by adding the heights in order from left to right. This chart is used widely in quality control settings to identify critical factors leading to failure or defects in a process. This article presents revis...

Recently, a treponema-specific immunoglobulin G (IgG) enzyme immunoassay (EIA), the CAPTIA Syphilis-G (Trinity Biotech, Jamestown, N.Y.), has become available as a diagnostic test for syphilis. A total of 89 stored sera previously tested by the fluorescent treponemal antibody absorption (FTA-ABS) IgG assay were evaluated by the CAPTIA EIA. The FTA-ABS IgG procedure was performed by technologist...

The most well-known uni-arribute control chart used to monitor the number of nonconformities per unit is the Shewhart type C-chart. In this paper, a new method is proposed in an attempt to reduce the false alarm rate in the C-chart. To do this, the decision on beliefs (DOB) concept is first uti [1] Corresponding author e-mail: [email protected]   lized to design an iterative method, where...

this study was conducted to determine the best pollinizer for five selected pecan cultivars in southwest of iran at safiabad agricultural research center in 2014-2015. the cultivars included: 'gratex', '10j', 'wichita 6j', 'graking', 'choctaw' as pollinated cultivars (♀) and 'gratex', 'peruque', 'comanche 4m', &apos...

in this research, an iterative approach is employed to recognize and classify control chart patterns. to do this, by taking new observations on the quality characteristic under consideration, the maximum likelihood estimator of pattern parameters is first obtained and then the probability of each pattern is determined. then using bayes’ rule, probabilities are updated recursively. finally, when...

although control charts are very common to monitoring process changes, they usually do not indicate the real time of the changes. identifying the real time of the process changes is known as change-point estimation problem. there are a number of change point models in the literature however most of the existing approaches are dedicated to normal processes. in this paper we propose a novel appro...

Minerals are defined as naturally occurring, inorganic, solids with a definite chemical composition and a regular, internal crystalline structure. The keys to this definition are the chemical composition and the crystalline structure. Different chemical compositions result in different minerals. A good example is the mineral plagioclase. Plagioclase is a member of the feldspar group, but there ...