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Atul Dev

Excellence Ambassador
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About Atul Dev

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    Atul Dev
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  1. Efficient, Effective

    Doing the right thing is effectiveness whereas doing things rightly is efficiency. Effectiveness comes first, to be followed by efficiency.
  2. ARMI / RACI

    RACI and ARMI both are responsibility assignment matrix for GRPI (goals, roles, processes and interpersonal relationship). In my view RACI is more related to responsibility assignment whereas ARMI is more related to project approval and team formation. These two tools should be used as per requirement.
  3. Specification Limits

    For a new product, for which VOC is not known, specifications limit for critical parameters can be simply fixed at x bar +/- 6 sigma, where x bar is the mean value of critical parameter when production is carried out under standard conditions and the product also meets the test qualification criteria. This will ensure 6 sigma process without any additional cost. Once the product is launched, VOC would be known and it can be used to fine tune the specification limits.
  4. Rolled Throughput Yield

    RTY is a measure of internal efficiency. The process with 100℅ RTY can still be considered inefficient in comparison with other more efficient processes giving same output.
  5. Coefficient of Variation (CoV) is the ratio of Standard Deviation and the Mean. It is a unitless ratio. CoV is an overall indicator of relative risk. For example, there are two different investment options. Stock A has an expected return of 15% and Stock B has an expected return of 10%. Stock A has a standard deviation of 10% whereas Stock B has a standard deviation of 5%. Which one is a better investment? If we compare the CoV of both the options, it shows that Stock B is a better option, since CoV of Stock B is 5/10 i.e. 0.5 whereas CoV for Stock A is 10/15 i.e. 0.67. Lesser the CoV more consistent are the returns.
  6. Lead Time, Cycle Time

    Lead Time is basically from customer's point of view, whereas Cycle Time is from process' point of view. Lead time starts when a request for delivery of a product or service is made and ends when this product or service is delivered to the customer. Cycle time starts when actual work begins on product or service and ends when that product or service is ready for delivery.
  7. Zero Defects

    I would like to support the view expressed in Para A. Quality is essentially a Top Down approach, and setting goals and formally expressing them actually helps because it shows Top management's intent and fixes their liability too.
  8. What i have practically experienced, Fishbone Diagram (which is a powerful root cause analysis tool) can be miused in following two ways: 1) When we already know the root cause of the problem and still develop a beautiful and impressive Fishbone Diagram just for fun sake! 2) When we don't involve all the stakeholders and try to develop a Fishbone Diagram single handedly. I feel use of Fishbone Diagram in root cause analysis is a collective exercise and hence shall be done in a systematic and honest manner.
  9. Segmentation

    Segmentation helps in understanding the data, which is required for Root Cause Analysis too. Data can be segmented into four categories: 1) Correlated Factors: these are the factors which are other symptoms of the root cause. 2) Unrelated Factors: these factors are not related to the change. 3) Contributing Factors: they are part of the chain of events that caused the chain, but are not the root cause. 4) Root Cause: these are the factors that initiated the chain of events that resulted in the change. So, segmentation of data obviously helps in Root Cause Analysis.
  10. Quality Costs

    Striking and equilibrium between Appraisal + Prevention costs and Internal + External failure costs was an old idea, when it was believed that 'zero rejection' level can not be achieved and such efforts will lead to infinite cost. But now a days, concept has changed, attaining zero rejection level is very much feasible within reasonable cost. Hence ideal situation is spend reasonable amount of money on Appraisal and Prevention costs to attain near zero Internal and External failure rate.
  11. 8D Problem Solving

    Though DMAIC is much powerful problem solving technique but still 8D problem solving technique may also be useful in certain situations, especially when we need some quick-fix solution before arriving at the final or say permanent solution. As compared to DMAIC, one of the fundamental difference of 8D technique is that it has an Interim Containment step, which is kind of band-aid approach useful to give some immediate relief, but still root cause analysis would be required to find a permanent solution. In certain situations, when the business problem is serious enough, it is justified to go for band-aid approach to stop the bleeding, then work on finding the root cause and remove the band-aid after implementing the permanent solution. But one should be cautious with 8D approach because sometimes this Interim Containment step can give a false sense of finding the solution and moving on to the next problem.
  12. Sigma Level

    Short term and long term sigma levels can certainly be calculated using short term process capability index (Cp) and long term process capability index (Pp) respectively. But generally, calculation of long term standard deviation is bit tricky as it requires collection of data over a long period of time. Most of the time, what we calculate is short term standard deviation and hence we calculate short term sigma level, whereas we are infact interested in long term performance of the process and thus we are more interested in long term sigma level of the process. Easiest way of calculating long term sigma level is by deducting 1.5 from the short term sigma level, which is done to accommodate shift of process mean by +/- 1.5 sigma in the long run.
  13. Outlier

    In statistics, outlier is a data point which is significantly different from other data points in a sample. It can occur due to wrong data collection /measurement error or actually due to some sudden and temporary variation in process. Keeping outliers in analysis may lead to wrong results hence its necessary to identify and remove them from the analysis. If data set is represented graphically, outlier point would be far away from the other values. Box Plot or Probability Plots are good tools for screening the data for outliers. Dixon's Test may be used to identify single outlier. Rosener's Test helps to identify multiple outliers in a data set. IQR method can be easily used to identify outliers. This method sets upper and lower limits beyond which any data point would be termed as outlier. In any data set, first we have to calculate the quartile (lower quartile is the data point below which 25 percent of the observations fall)
  14. VOC, VOB

    Sometimes Voice of Customer and Voice of Business may be conflicting. One of the most common reason of conflict may be price. A customer wants best quality at lowest price whereas the business has to earn profit to survive in the long run. Hence price is obviously a conflicting issue between customer and business interests.