SCM 405 Exam 1 Flashcards
Corporate strategy
- select the market in which to compete in
- acquire and allocate resources to the business unit
Levels of strategy
corporate strategy
business unit strategy
functional (manufacturing) strategy
Business unit strategy
- identify the boundaries of the markets served
- select the desired competitive advantage
Functional (Manufacturing) Strategy
- determine how best to support the competitive advantage
- integrate and communicate with other functions
Supporting the competitive advantage (measure of manufacturing success)
- cost
- conformance quality (reliability)
- time to market (speed)
- flexibility
- delivery dependability
work station (station)
a collection of one or more identical machines
parts (jobs)
a component, sub-assembly, or an assembly that moves through the work stations
production line (line)
sequence of workstations needed to make a part
Performance measures
Throughput (TH)
Cycle Time (CT)
Work in progress (WIP)
Throughput (TH)
average quantity of good (non-defective) parts produced per unit time
Cycle Time (TH)
average time it takes for a part to travel between the start and endpoint of a production line (has no unit of time)
Work in Progress (WIP)
average inventory between the start and endpoint of production line
Line Parameters
represent the optimal performance of a production line. this is the best the production line can perform
Types of line parameters
Bottle Neck Rate
Raw processing time
Critical WIP
Bottle neck rate
- Average processing rate (part/time) of the slowest work station
- On a line with multiple parts, Rb, will depend on the product mix
- TH is always less than or equal to bottle neck
Raw process time
- sum of the average process times of each workstation in the production line
- this doesn’t include wait time
- Cycle time d greater than or equal to raw process time
Critical WIP
- WIP level in which a line with no variability would achieve both maximum TH and minimum CT
- TH = bottle neck rate
- Cycle time = raw process time
Little’s law
- Fundamental relationship between WIP, TH, and CT over the long-term
- WIP = TH * CT (rate * time)
- those performance measures are long term average
What is variability?
any departure from uniformity
Classes: common cause and assignable cause
What is variability?
any departure from uniformity
Classes: common cause and assignable cause
Common cause (random)
artifact of incomplete knowledge
variability that we don’t understand what is causing it
management implication: robustness is key
Assignable cause (controllable)
variability that we know what is causing it
Sources of variability
machine failure set up material shotages yield loss rework operator unavailiabilty
process time in relation to variability
natural process time usually have LV (low variabilty)
For effective process time; LV, HV,MV are all possible