Variability Basics - Flow Variability

3 important questions on Variability Basics - Flow Variability

Consider a line with machine A, having a certain  , feeding another machine B without yield loss. Now consider the exact same line but with yield loss. What parameter changes for machine B?

The utilization (u) changes since it gets less jobs to process. (Whether this increases or decreases the values of Cd is dependent on the values of Ce and Ca.)

What happens with the SCV of the time between arrivals  to a station and the SCV of effective process time at a station if they are respectively poisson distributed and constant?

1. 

2.

 

 

A workstation receives a batch of 28 jobs once per shift ( 6 hours). Give the mean time between arrivals (Ta) and its variance .

the mean time between arrivals equals (6/28) ≈ 0,21 hour

 

the variance equals:

 

 = [ (1/28)*(6^2) + (27/28)*(0^2)] - Ta^2 = ((1/28)*36) - (6/28)^2 ≈ 1,24

 

 

The question on the page originate from the summary of the following study material:

  • A unique study and practice tool
  • Never study anything twice again
  • Get the grades you hope for
  • 100% sure, 100% understanding
Remember faster, study better. Scientifically proven.
Trustpilot Logo