Exam 2 Material 3, 5, 11, 14, 17 Flashcards
What is a forecast?
a statement about the future value of a variable of interest
What are two important aspects of forecast?
- expected level of demand
2. accuracy
Explain time-series forecast
a time-ordered sequence of observations taken at regular time intervals
5 time series behaviors
- trend
- seasonality
- cycles
- irregular variations
- random variation
Explain trend
a long-term upward/downward movement in data
Explain Cycle
wavelike variations lasting more than one year
Explain Naive
uses a single previous value of a time series as the basis for a forecast
Explain moving average
averages a number of the most recent actual values in generating a forecast
Explain weighted moving average
most recent values in a time series are given more weight in computing a forecast
Explain exponential smoothing
based on previous forecast plus a percentage of forecast error
What is capacity?
The upper limit or ceiling on the load that an operating unit can handle
What is design capacity?
max output rate or service capacity of an operation, process or facility it is designed for
What is effective capacity?
design capacity-allowance such as personal time and maintenance
What is efficiency?
actual/effective
What is utilization?
actual/design
Explain leading
build capacity in anticipation of future demand increases
Explain following
build capacity when demand exceeds current capacity
Explain tracking
Add capacity in relatively small increments to keep pace with increasing demand
Short term considerations relate to ____ in capacity requirements
variations
long term considerations relate to ______ in capacity requirements
level
Name 3 challenges related to service capacity
- need to be near customers
- inability to store services
- degree of demand volatility
Name strategies used to offset capacity limitations and that intended to achieve a closer match between supply and demand
pricing, promotion, discounts
What is a bottleneck operation?
an operation in a sequence of operations whose capacity is lower than that of the other operations
Explain economies of scale
if output rate is less than optimal level, increasing the output rate results in decreasing average per unit costs
Explain diseconomies of scale
if output rate is less than optimal level, increasing the output rate results in increasing average per unit costs
What is the break even point?
the volume of output at which total cost and total revenue are equal
What is aggregate planning?
production plan that will effectively utilize the organization’s resources to satisfy demand
What are aggregated planners concerned with?
demand quantity and timing of demand
What does aggregate planning project levels of?
inventory, output, employment, subcontracting, backordering
Explain proactive
alter demand to match capacity
Explain reactive
alter capacity to match demand
What is level capacity?
maintaining a steady rate of regular-time output while meeting variations in demand by a combination of inventory, overtime, part-time workers, back orders,
What is chase demand?
matching capacity to demand, the planned output for a period is set at the expected demand for that period
What is yield management?
maximizing revenue by during times of low demand, disscouting, and high demand raising prices
What are the two sides of project triangle and what is on the bottom?
two sides: costs and schedule
bottom: project objectives
Who is the project champion?
a person who promotes and supports a project
What is the critical path?
longest path
What is optimistic time?
length of time required under optimal conditions
what is most likely time?
most probably length of time required
What is pessimistic time?
length of time required under the worst conditions
What is crashing?
shortening activity durations, often by increasing direct expenses
What is a lean operation?
a flexible system of operation that uses considerably less resources than a traditional system
Name 5 characteristics of lean systems
- waste reduction
- continuous improvement
- use of teams
- high quality
5 minimal inventory
What are benefits of lean production?
- reduce waste
- lower cost
- increase quality
- reduce cycle time
- increase production/flexibility
What are risks to lean production?
- stress on workers
- fewer resources available
- supply chain disruptions
What was lean operations known as in the mid 1900’s
JIT
Who developed lean and from where
Taiichi and Shigeo Ohno of Toyota
What is the ultimate goal of lean
achieve a balanced system
Explain Kaizen
attacking waste
Name 4 elements of product design
- standard parts
- modular design
- highly capable system with quality built in
- concurrent engineering
Name 8 aspects of process design related to lean
- small lot sizes
- set up time reduction
- manufacturing cells
- quality improvement
- production flexibility
- balance system
- little inventory storage
- fail-safe methods
What is the ideal lot size in lean?
1
What is SMED
single-minute exchange of die:
- reducing changeover time
What is jidoka?
automatic detection of defects during production
What is poka-yoke?
building safeguards into a process to reduct or eliminate potential errors during a processes (safe-guarding)
What is activity based costing?
allocation of overhead to specific jobs based on their percentage of activities
Wha is a push system?
work is pushed the next station as it is completed
What a pull system?
output is given to the next station as it is needed
What is kanban?
signal, card or other device that communicates demand for work or materials from the preceding station
What is value stream mapping?
visual tool to systematically examine the flows of materials and information
What are the 5 S’s
- set
- sort
- shine
- standardize
- sustain
What does downtime stand for?
D-defects O- overtime W- waiting N- not utilizing talent T-transportation I- inventory M-motion E- excess process
