2. CH7

Question 1

Little’s Law

Answer 1

WIP = TH•CT

Question 2

The average quantity of good (non-defective) parts produced per unit time

Answer 2

Throughput (TH)

Question 3

Material stocked at beginning of routing

Answer 3

Raw material inventory

Question 4

Material held in a stock-point at the beginning of a routing

Answer 4

Crib inventory

Question 5

Material held in inventory prior to shipping to the customer

Answer 5

Finished goods inventory (FGI)

Question 6

Time between release of the jobs at the beginning of the routing until it reaches an inventory point at the end of the routing

Answer 6

Cycle Time (CT)

Question 7

Service Level

Answer 7

Pr(Cycle Time <= Lead Time)

Question 8

A manufacturing system is a goal-oriented network of process through which parts flow

Answer 8

Factory Physics Definition

Question 9

Plant is made up of routing (lines), which in turn are made up if processes

Answer 9

Factory Physics Structure

Question 10

Rate (parts or jobs/unit of time) of the process center having the highest long-term utilization

Answer 10

Bottleneck rate (rb)

Question 11

Sum of the long-term average process times of each station in the line

Answer 11

Raw Process Time (T0)

Question 12

A unit-less measure of congestion

Answer 12

Congestion coefficient (alpha)

Question 13

Alpha = 0

Answer 13

Zero variability case

Question 14

Alpha = 1

Answer 14

Practical worst case

Question 15

Alpha = Critical WIP (W0)

Answer 15

Worst possible case

Question 16

Maximum throughput with minimum cycle time

Answer 16

Critical WIP (W0)

Question 17

Critical WIP (W0)

Answer 17

W0 = rb•T0

Question 18

Max TH, min CT, no randomness

Answer 18

Best case performance

Question 19

Min TH, max CT, no randomness

Answer 19

Worst case performance

Question 20

In a balanced line, Critical WIP (W0) = Number of machines

Answer 20

In an unbalanced line, Critical WIP (W0) < Number of machines

Question 21

Maximum randomness

Answer 21

Practical worst case (PWC)

Question 22

Conditions for PWC

Answer 22

1. Balanced line
2. Single machines
3. Memoryless

Question 23

If we improve the non-bottleneck

Answer 23

Then rb does not change, but it serves to reduce randomness

Question 24

Unbalanced lines exhibit

Answer 24

Less congestion than balanced lines