Abstract This paper presents a correction plan for maintaining high quality level of production processes. The Graphical Evaluation and Review Technique (GERT) is applied to model and analyze the dynamic characteristic of the plan. Unity values are tabulated to facilitate operation and...

Abstract Industrial quality control is necessary at least for two reasons: Monitoring product or process quality in order to perform interventions for assuring a desired quality level. Monitoring product or process quality in order to meet certain requirements (imposed by law or customers) for...

Abstract Consider the following two situations which are characteristic for the application of statistical procedures. 1.) There is a deterministic variable of interest , whose actual value θ ∈ Θ is unknown. 2.) There is a random variable of interest with uncertain outcome . The aim in the...

Abstract Consider a product with quality characteristic X . Assume that the product is composed of n parts each with quality characteristic X i , and and let X = X 1 + . . . + X n Assume that there is a lower specification L and an upper specification U for X . Then the problem arises how to...

Abstract In this paper, we extend Johnson's work [Johnson, T. Journal of Quality Technology 24: 211-215, 1992] of formulating the relationship between process capability indices (PCI) and expected squared error losses. Moreover, a comparison is made between the expected squared error loss of PCI...

Abstract In this paper we present a mathematical model of a generic manufacturing system. The quality of the manufactured product is captured through one or more of its critical design/process parameters. Managers often face the dilemma of which product/process is to be singled out for...

Abstract In 1986 Taguchi presented the quadratic function for describing the loss of quality due to deviation from the production value. The objective then is to improve quality by minimizing the quadratic loss function which reflects the loss of both, the producer and the consumer....

Abstract One widely used control chart, the -chart, is based on the assumption that means of samples drawn from the process are normally distributed. When the normality assumption is not valid, control chart users may choose from several different courses of action. These include using Box-Cox...

Abstract A common replacement policy for technical systems consists in replacing a system by a new one after its economic lifetime, i.e. at that moment, when its long-run maintenance cost rate is minimal. The strict application of the economic lifetime does not take into account individual...

Abstract The average probability of acceptance ( APA ) is obtained for a single sampling plan assuming a Gamma prior distribution. Formula for inflection point and tangent at the inflection point are also derived. Tables are provided for selection of plan parameters.