GENERAL ARTICLE

How to control process variability more effectively: The case of a B-complex vitamin production process

M.A. Djauhari^I; I. Mohamad^II

^IDepartment of Mathematics, Universiti Teknologi Malaysia, Malaysia maman@utm.my
^IIDepartment of Mathematics, Universiti Teknologi Malaysia, Malaysia im@mel.fs.utm.my

ABSTRACT

This paper presents a new procedure for controlling process variability where (i) the quality of the process is determined by more than one quality characteristic, and (ii) the correlations among those quality characteristics must be taken into consideration. The ability of this procedure to detect an abrupt shift of covariance structure is an improvement on the standard practice based on generalised variance. An experience of the production process of the B-complex vitamin is reported to illustrate the merit of the proposed procedure.

OPSOMMING

Die metodes van 'n nuttige gehaltebeheerprosedure vir die bepaling van gehaltebeheerverlies wat 'n chemiese produk met meervoudige gehalte-eienskappe besit, word beskryf teen die agtergrond van kovariasie. Die prosedure word getoets in die praktyk by die vervaardiging van 'n gegewe chemiese produktipe. Aspekte van voordele en nadele van die metode word ook gewetensgetrou behandel.

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REFERENCES

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