Sunday, September 18, 2011

Alpha Risk & Beta Risk

Alpha Risk : Also name as Type I Error, is the risk of rejecting the Null Hypothesis when in fact it is true.

Example of Type I Error;
Production operator is making a wrong judgement to reject a good part. Therefore producer is facing some level of risk to loss due to the Type I error commit by the production operator, because of this, Type I Error ( Alpha Risk ) also name as Producer Risk.

Better Risk : Also name as Type II Error, is the risk of accepting the Null Hypothesis when in fact it is false.

Example of Type II Error;
Production operator is making a wrong judgement to accept a rejected part. Due to rejected parts was accepted and deliver to the market, consumer is facing some level of risk to accept the rejected part. Therefore, Type II error also name as Consumer Risk.

Alpha Risk and Beta Risk is used in Power & Sample Size estimation

Saturday, September 3, 2011

Kanban Card In Inventory Control

Days after the presentation, I try to meet up with VJ to understand his problem and the requirement of inventory control. He tell me he need to keep 5 rolls tape in the cabinet, and the supervisor is required to trigger stock replenishment when the found 2 rolls left.

I explain to him about the Kanban Card control and his problem can be easily solve with Kanban Card. Here the solution I propose to him

1. He has to prepare 6 Kanban Card as shown

2. He has to prepare a display board to store the Kanban Card every time operator withdraw the material from the cabinet.

With the 2 system in placed, now the supervisor’s job become very easy. What they need to do is just look at the display board and trigger stock replenishment on those envelope that fill up with Kanban Card.




I think this is a very simple visual control system that can be apply without incur much cost. The production control executive can just manage the inventory by controlling the Kanban Card qty. Supervisor can just perform their daily function by looking at the Display Board.

Is this a better and practical idea ?