Contenu connexe
Similaire à CH13.PPT (20)
CH13.PPT
- 1. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-1
Operations
Management
Aggregate Planning
Chapter 13
- 2. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-2
Outline
GLOBAL COMPANY PROFILE: ANHEUSER-
BUSCH
THE PLANNING PROCESS
THE NATURE OF AGGREGATE PLANNING
AGGREGATE PLANNING STRATEGIES
Capacity Options
Demand Options
Mixing Options to Develop a Plan
- 3. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-3
Outline - Continued
METHODS FOR AGGREGATE PLANNING
Graphical and Charting Methods
Mathematical Approaches to Planning
Comparison of Aggregate Planning Methods
AGGREGATE PLANNING IN SERVICES
Restaurants
Hospital
Miscellaneous Services
National Chains of Small Service Firms
Airline Industry
YIELD MANAGEMENT
- 4. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-4
Learning Objectives
When you complete this chapter, you should be
able to :
Identify or Define:
Aggregate planning
Tactical scheduling
Graphic technique for aggregate planning
Mathematical techniques for aggregate planning
Describe or Explain:
How to do aggregate planning
How service firms develop aggregate plans
- 5. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-5
Anheuser-Busch
Anheuser-Busch produces nearly 40% of the beer
consumed in the U.S.
Matches fluctuating demand by brand to specific
plant, labor, and inventory capacity
High facility utilization requires
meticulous cleaning between batches
effective maintenance
efficient employees
efficient facility scheduling
- 6. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-6
Aggregate Planning Requires
Logical overall unit for measuring sales and
outputs
Forecast of demand for intermediate planning
period in these aggregate units
Method for determining costs
Model that combines forecasts and costs so that
planning decisions can be made
- 7. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-7
Setting goals & objectives
Example: Meet demand within the limits
of available resources at the least cost
Determining steps to achieve goals
Example: Hire more workers
Setting start & completion dates
Example: Begin hiring in Jan.; finish, Mar.
Assigning responsibility
Planning
- 8. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-8
Planning Tasks and Responsibilities
- 9. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-9
Planning Horizons
Today 3 Months 1 year 5 years
Planning Horizon
Short-range plans
Job assignments
Ordering
Job scheduling
Dispatching
Intermediate-range plans
Sales planning
Production planning and
budgeting
Setting employment, inventory,
subcontracting levels
Analyzing operating plans
Long-range plans
R&D
New product plans
Capital expenses
Facility location, expansion
Responsible:
Operations
managers,
supervisors,
foremen
Responsible:
Operations
managers
Responsible:
Top executives
- 10. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-10
Relationships of the Aggregate Plan
Aggregate
Plan for
Production
Demand
Forecasts,
orders
Master
Production
Schedule, and MRP systems
Detailed Work
Schedules
External
Capacity
Subcontractors
Inventory On
Hand
Raw Materials
Available
Work Force
Marketplace
and Demand
Research and
Technology
Product
Decisions
Process
Planning & Capacity
Decisions
- 11. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-11
A mathematically based aggregate planning model requires
considerable:
time
problem definition
model development
model verification
model application
expertise
people who understand the problem
people who understand both the modeling process, and the
specific model
money
money to pay for all of the above
often requires funding for several people for several months!
What’s Needed for Aggregate
Planning
- 12. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-12
Provides the quantity and timing of production for
intermediate future
Usually 3 to 18 months into future
Combines (‘aggregates’) production
Often expressed in common units
Example: Hours, dollars, equivalents
(e.g., FTE students)
Involves capacity and demand variables
Aggregate Planning
- 13. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-13
Meet demand
Use capacity efficiently
Meet inventory policy
Minimize cost
Labor
Inventory
Plant & equipment
Subcontract
Aggregate Planning Goals
- 14. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-14
Aggregate Planning Strategies
Pure Strategies
Capacity Options — change capacity:
changing inventory levels
varying work force size by hiring or layoffs
varying production capacity through overtime or idle
time
subcontracting
using part-time workers
- 15. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-15
Aggregate Planning Strategies
Pure Strategies
Demand Options — change demand:
influencing demand
backordering during high demand periods
counterseasonal product mixing
- 16. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-16
Aggregate Scheduling Options -
Advantages and Disadvantages
Option Advantage Disadvantage Some
Comments
Changing
inventory levels
Changes in
human resources
are gradual, not
abrupt
production
changes
Inventory
holding costs;
Shortages may
result in lost
sales
Applies mainly
to production,
not service,
operations
Varying
workforce size
by hiring or
layoffs
Avoids use of
other alternatives
Hiring, layoff,
and training
costs
Used where size
of labor pool is
large
- 17. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-17
Option Advantage Disadvantage Some
Comments
Varying
production rates
through overtime
or idle time
Matches seasonal
fluctuations
without
hiring/training
costs
Overtime
premiums, tired
workers, may not
meet demand
Allows
flexibility within
the aggregate
plan
Subcontracting Permits
flexibility and
smoothing of the
firm's output
Loss of quality
control; reduced
profits; loss of
future business
Applies mainly
in production
settings
Advantages/Disadvantages -
Continued
- 18. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-18
Advantages/Disadvantages -
Continued
Option Advantage Disadvantage Some
Comments
Using part-time
workers
Less costly and
more flexible
than full-time
workers
High
turnover/training
costs; quality
suffers;
scheduling
difficult
Good for
unskilled jobs in
areas with large
temporary labor
pools
Influencing
demand
Tries to use
excess capacity.
Discounts draw
new customers.
Uncertainty in
demand. Hard to
match demand to
supply exactly.
Creates
marketing ideas.
Overbooking
used in some
businesses.
- 19. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-19
Advantage/Disadvantage -
Continued
Option Advantage Disadvantage Some
Comments
Back ordering
during high-
demand periods
May avoid
overtime. Keeps
capacity constant
Customer must
be willing to
wait, but
goodwill is lost.
Many companies
backorder.
Counterseasonal
products and
service mixing
Fully utilizes
resources; allows
stable workforce.
May require
skills or
equipment
outside a firm's
areas of
expertise.
Risky finding
products or
services with
opposite demand
patterns.
- 20. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-20
The Extremes
Level
Strategy
Chase
Strategy
Production
equals
demand
Production rate
is constant
- 21. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-21
Mixed strategy
Combines 2 or more aggregate scheduling options
Level scheduling strategy
Produce same amount every day
Keep work force level constant
Vary non-work force capacity or demand options
Often results in lowest production costs
Aggregate Planning Strategies
- 22. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-22
Graphical & charting techniques
Popular & easy-to-understand
Trial & error approach
Mathematical approaches
Transportation method
Linear decision rule
Management coefficients model
Simulation
Aggregate Planning Methods
- 23. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-23
The Graphical Approach to
Aggregate Planning
Forecast the demand for each period
Determine the capacity for regular time, overtime,
and subcontracting, for each period
Determine the labor costs, hiring and firing costs,
and inventory holding costs
Consider company policies which may apply to the
workers or to stock levels
Develop alternative plans, and examine their total
costs
- 24. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-24
Forecast and Average Forecast
Demand
0
10
20
30
40
50
60
70
Production
rate
per
working
day
Jan Feb Mar Apr May Jun
Forecast
Demand
Level production using
average monthly
forecast demand
22 18 21 21 22 20
- 25. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-25
Cumulative Demand Graph for
Plan 1
Jan Feb Mar Apr May Jun
Cumulative forecast
requirements
Cumulative level
production using
average monthly
forecast
requirements
Reduction of
inventory
Excess inventory
Cumulative
Demand
(Units) 7,000
6,000
5,000
4,000
3,000
2,000
1,000
- 26. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-26
Farnsworth’s Transportation Table
Period 1
(Mar)
Period 2
(Apr)
Period 3
(May)
Unused Capacity
(Dummy)
Total Capacity Available
(Supply)
Beginning
Inventory
0
100
2 4 0
100
Regular 40
700
42 44 0
700
Overtime 50 52
50
54 0
50
Subcontract 70 72
150
74 0
150
Regular X 40
700
42 0
700
Overtime
X
50
50
52 0
50
Subcontract
X
70
50
72 0
100 150
Regular
X X
40
700
0
700
Overtime
X X
50
50
0
50
Subcontract
X x
70 0
130
Total Demand 800 1000 750 230 2780
Period
3
Period
2
Period
1
- 27. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-27
Comparison of Three Major
Aggregate Planning Methods
Charting/graphical
methods
Transportation method
Management
coefficient model
Trial and error
Optimization
Heuristic
Simple to understand, easy to
use. Many solutions; one
chosen may not be optimal
LP software available;permits
sensitivity analysis and
constraints. Linear function
may not be realistic
Simple, easy to implement;
tries to mimic manager’s
decision process; uses
regression
Techniques Approaches Aspects
- 28. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-28
Controlling the Cost of Labor in
Service Firms
Seek:
Close control of labor hours to ensure quick response
to customer demand
On-call labor resource that can be added or deleted to
meet unexpected demand
Flexibility of individual worker skills to permit
reallocation of available labor
Flexibility of individual worker in rate of output or hours
of work to meet demand
- 29. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-29
Making Yield Management Work
Multiple pricing structures must be feasible and
appear logical
Forecast the use and duration of use.
Manage the changes in demand.
- 30. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-30
Hotel: Single Price Level
$15 variable cost
of room
$150 Price
charged for room
Price
Sales
$sales = Net price
* 50 rooms
=150*50
=$7500
Demand Curve
Passed up
profit
contributions
Money left
on the table
Potential customers exist who are willing
to pay more than the $15 variable cost
Some customers who
paid $150 for the room
were actually willing to
pay more
- 31. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-31
Hotel: Two Price Levels
$15 variable
cost of room
Demand
Sales
$100
Price #1
$200
Price #2
Total sales =
1st net price *30 +
2nd net price *30
= $8100
Net prices are:
Price #1 => $85
Price #2 => $175
- 32. Transparency Masters to accompany Heizer/Render –
Principles of Operations Management, 5e, and Operations
Management, 7e
© 2004 by Prentice Hall, Inc. Upper Saddle River, N.J. 07458
13-32
Yield Management Matrix
Fixed Variable
D
u
r
a
t
I
o
n
o
f
u
s
e
Predictable
use
Quadrant 1
Movies, stadiums,
arenas, convention
centers, hotel
meeting space
Quadrant 2
Hotels, Airlines,
Rental
cars,Cruise
lines
Unpredictable
use
Quadrant 3
Restaurants,Golf
courses, Internet
service providers
Quadrant 4
Continuing care
hospitals