Lecture 31:
Scheduling Systems 1
© J. Christopher Beck 2008
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Outline
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Databases & Knowledge-bases
Optimization Module
User Interface
© J. Christopher Beck 2008
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Readings
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P Ch 13.2,
13.3, 13.4,
13.5
© J. Christopher Beck 2008
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Manufacturing
Scheduling
Systems
Production planning,
master scheduling
Capacity
status
Scheduling
constraints
Quantities,
due dates
Material requirements
planning,
capacity planning
Scheduling
performance
Schedule
Dispatching
Shop floor management
Job loading
Shop floor
Material
requirements
Shop orders,
Release dates
Scheduling
and
rescheduling
Data
collection
Orders, demand
forecasts
Shop
status
Detailed
scheduling
Service Scheduling Systems
Status
Database
Database
Forecasts
Data
Yield management
Scheduling
Pricing
Accept/
reject
Orders,
reservations
Customer
© J. Christopher Beck 2008
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Scheduling System Itself
Database Interface
Schedule Generator
Schedule Editor
DB
?
KB
Performance Evaluator
GUI
© J. Christopher Beck 2008
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Database
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Plant layout, resources
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planned maintenance, calendars
Jobs/process plans
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DB
Recipe for each order
Processing times, routings, etc.
Bill of materials
Set-up times
Customer/Supplier details (priorities)
© J. Christopher Beck 2008
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Database: Orders
Ex: Paper Mill
Comment
Width
DB
Basis Grade Finish Quantity Due date
Date
Weight
produced
Order
Customer
PUR01410
UZSOY CO
16.0
5.0
29.0
55.0
05/25
05/24
PUR01411
UZSOY CO
16.0
4.0
29.0
20.0
05/25
05/25
PUR01412
UZSOY CO
16.0
4.0
29.0
35.0
06/01
TAM01712
CYLEE LTD
14.0
3.0
21.0
7.5
05/28
05/23
TAM01713
CYLEE LTD
14.0
3.0
21.0
45.0
05/28
05/23
TAM01713
CYLEE LTD
16.0
3.0
21.0
50.0
06/07
EOR01310
LENSTRA NV
16.0
3.0
23.0
27.5
06/15
© J. Christopher Beck 2008
CMT WDT BW
PR
HLD
GR
FNSH QTY DDT
PRDT
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Schedule Generation Module
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Some sort of custom built “system”
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May be done by hand or with Excel!
DB
download
up-to-date
information
publish!
iterate
Build schedule
© J. Christopher Beck 2008
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Building Schedule
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Any (or none!) of the scheduling
techniques we discussed in this course
could be used
It may be a mix of heuristics and
human intervention or may be a more
sophisticated system (e.g., based on CP
or local search)
© J. Christopher Beck 2008
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GUI
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Should allow wide range of interaction
User should be able to
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schedule by hand
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change schedules
make some decisions
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(i.e., place activities where ever they like)
let the schedule builder do the rest
let the schedule builder do everything
© J. Christopher Beck 2008
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GUI
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The user knows more than the system!
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System needs to allow the user to make
“bad” decisions from the system’s point of
view
What-if analysis
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“If I put this job on this machine, what
happens?”
“If this machine goes down for
maintenance …?”
© J. Christopher Beck 2008
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GUI
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Provides schedule evaluation
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Does the schedule break any constraints?
Multiple optimization criteria
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There might really be more than one criteria!
© J. Christopher Beck 2008
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