jericho
5th June 2006, 03:03 AM
Hi, after 250 hours of work experience and learning here in my company - internship site, i am not yet finished with my process improvement project. Can anybody there help me?
My professor at the University of the Philippines asked me that the methods that i should follow in the problem analysis part of my manuscript is something like Pareto-Ishikawa-CNX-SOP analysis.
Please, i am quite unfamiliar with the CNX part. Can anybody help me? I tried to research it at isixsigma.com but to no avail. Please. Thanks.
Hope somebody helps. :cfingers:
apestate
5th June 2006, 03:53 AM
I was curious myself so I did some searching:
PF/CE/CNX/SOP: A methodology that is used to reduce extraneous variation. It uses process flow diagrams (PF) and cause and effect diagrams (CE) to identify and sort the causes of variation. The causes are further categorized as controllable (can be held constant “C”), noise (too difficult or expensive to control “N”) or experimental (factors which must be investigated to understand their impact “X”). Standard operating procedures (SOP) are used to establish methods for holding the “C” factors constant.
http://www.airacad.com/WhatIsDefinitions.aspx
Most of the valid results were about "lean six sigma" and root cause investigations.
Marc
5th June 2006, 07:28 AM
Thanks, atetsade!
Is anyone else familiar with this technique?
e006823
5th June 2006, 09:24 AM
PF/CE/CNX/SOP is part of the 6 Sigma tool set as an analysis tool. The general process is:
PF = Process Flow
–Map or flowchart the process
–Identifies sources of waste, decision points, and loops
–Identifies flow of materials and information
CE = Cause & Effect
–Brainstorm potential sources of variation
–Promotes out of the box thinking and employee involvement
CNX = Constant, Noise, and Experimental
–Classify all sources of variation
–Constant factors can be controlled
–Noise factors cannot be controlled or are chosen not to be held constant
–Experimental factors can be tested at different options or settings
SOP = Standard Operating Procedure
–For all C’s or Constants on the Cause & Effect
–Explain how to hold the factors constant
jericho
5th June 2006, 08:28 PM
Thanks for the info, but now that i know the definition of CNX, how do i apply that in my manuscript?
Would be it like a classification type? Like, the C, N and X listed above and putting the right problem under it?
Unlike Pareto, Ishikawa, etc with which I have a good grasp on, i dunno much on how to do CNX... What are the definite criteria for a problem to be defined as C, N X anyway? Thanks so much!!:confused:
apestate
6th June 2006, 12:31 AM
CNX is extremely familiar in the context of statistical process control.
The Constant factor of CNX is the same as special causes of variation in SPC. The Noise factor of CNX is the same as common causes of variation in SPC.
You shouldn't have to look too far to find examples of the Experimental factor of CNX.
I highly recommend reading some overview of statistical process control materials. This will elucidate further what you may already know about statistics and reducing variation in the scope of six sigma improvement projects.
http://www.statit.com/statitcustomqc/StatitCustomQC_Overview.pdf
http://www.skymark.com/resources/tools/control_charts.asp