Production
and Operations Management
MGT613
VU
Lesson
29
AGGREGATE
PLANNING
Learning
Objectives
Explain
the working and usefulness of Aggregate
Planning.
Identify
the variable decision makers to
work with in aggregate
planning and some of the possible
strategies
they can use.
Describe
some of the graphical and
quantitative techniques planners
use.
Prepare
aggregate plans and compare
their costs.
Planning
Horizon
Aggregate
planning:
Intermediate-range capacity planning,
usually covering 2 to 12 months.
Long
Range
Intermediate
Range
Short
Range
Now
2
months
1
Year
As
Operations Manager we should be able to
understand and identify the various
Planning Levels which
are
Short Range Plans,
Intermediate Plans and Long
Range Plans.
Short-range
plans (Detailed plans)
1.
Machine loading
2.
Job assignments
Intermediate
plans (General levels)
1.
Employment
2.
Finished Good
inventories
3.
Subcontracting, Backorders
4.
Output
Long-range
plans
1.
Long term capacity
2.
Location / layout
135
Production
and Operations Management
MGT613
VU
Planning
Sequence
Aggregate
Planning Inputs
Resources
1.
Workforce
2.
Facilities
Demand
forecast
Policies
1.
Subcontracting
2.
Overtime
3.
Inventory levels
4.
Back orders
Costs
1.
Inventory carrying
2.
Back orders
3.
Hiring/firing
4.
Overtime
5.
Inventory changes
6.
subcontracting
Aggregate
Planning Outputs
1.
Total cost of a plan
2.
Projected levels of inventory
3.
Inventory
4.
Output
5.
Employment
6.
Subcontracting
7.
Backordering
136
Production
and Operations Management
MGT613
VU
Aggregate
Planning Strategies
Proactive
Strategy: Strategies that
alter demand to match
capacity are known as
Proactive Strategy.
Reactive
Strategy: Strategies that
alter capacity to match
demand are known as Reactive
Strategy.
Mixed.
Strategies that make use of
qualities from both
Proactive and Reactive Strategy
are known
as
Mixed Strategies.
Demand
and Capacity Options
Demand
Options: The four common
demand options primarily focus on
market aspects apart
from
backorders
which is strictly operational
management in nature. The operations
manager should know
all
four
demand options but should be
more interested in back order
option.
1.
Pricing
2.
Promotion
3.
Back
orders
4.
New
demand
Capacity
Options: The common capacity
options primarily focus
on.
1.
Hire and layoff
workers
2.
Overtime/slack time
3.
Part-time workers
4.
Inventories
5.
Subcontracting
6.
Maintain a level
workforce
7.
Maintain a steady output
rate
8.
Match demand period by
period
9.
Use a combination of decision
variables
An
important point to be noted is
that Demand options are short range in
nature while Capacity
options
are
long duration (term or
range).
Which
Strategy to Use
The
organization needs to consider two
factors before choosing a strategy
1.
Costs
2.
Company/Corporate Policy
Policy
can
set
constraints
on
available
options.
E.g.
Layoffs,
subcontracting/Outsourcing
( PIA subcontracting its databases) to
protect secrecy.
As
a rule of thumb, aggregate planners
seek to match supply and
demand within in
constraints
by policies and minimum
costs.
137