Determination of Optimum Sample Size for Lot Acceptance Attribute Sampling under Life Tests Based On Rayleigh Distribution Using Graphical Evaluation Review Technique (GERT)

Pradeepa Veerakumari Kumarasamy,Thottathil Asif,Sivakasini Nagarathinam

doi:10.30699/ijrrs.3.2.11

Abstract

This paper presents the graphical evaluation and review technique (GERT) exploration of performance measures for lot acceptance sampling procedures having attribute characteristics following life tests based on percentiles of Rayleigh Distribution and henceforth determining optimum sampling size. The advantageous implications of GERT analysis in this framework is primarily to visualize the dynamics of the sampling inspection system and secondly, critical analysis of sampling procedure characteristics. The formula of operating characteristics (OC) function and average sample number (ASN) function is derived and illustrated numerically. Lastly, tables have been provided to determine the optimum sample size assuring certain mean life or quality of the product.

Highlights

This paper presents the graphical evaluation and review technique (GERT) exploration of performance measures for lot acceptance sampling procedures having attribute characteristics following life tests based on percentiles of Rayleigh Distribution and determining optimum sampling size
The prototypes used to determine the acceptability of a product for its lifetime are called reliability or life test prototype
When the life test shows that the mean or percentage life of the product is above the desired quality, the submitted lot is accepted; otherwise it is rejected lot

Summary

Introduction*

Acceptance model schemes are commonly used to determine product acceptance. Lifetime is an important quality attribute of an object. The prototypes used to determine the acceptability of a product for its lifetime are called reliability or life test prototype. When the life test shows that the mean (average) or percentage life of the product is above the desired quality, the submitted lot is accepted; otherwise it is rejected lot. Reliability sampling is a process that establishes the minimum sample size to be used for testing. This is especially valuable if the quality of an object is defined in its lifetime. A specific reliability model project, in which case, sample observation is subject to the lifetime testing of the products, is intended to demonstrate that the actual population average exceeds the required minimum. If ߠ଴ is a certain minimum value, one wants to check ߠ ൒ ߠ଴; Lots rejected or life test model plan

Reliability Functions

Life Distribution models and their characteristics

General Characteristics of Life Distributions

Lifetime under Inspection Using Regenerative Point