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Scheduling OperationsScheduling Operations

Chapter 13Chapter 13

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OutlineOutline

Batch SchedulingBatch Scheduling

Gantt ChartingGantt Charting

Finite Capacity SchedulingFinite Capacity Scheduling

Theory of ConstraintsTheory of Constraints

Dispatching RulesDispatching Rules

Infinite Capacity LoadingInfinite Capacity Loading

Planning and Control SystemsPlanning and Control Systems

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Batch SchedulingBatch Scheduling

Very complex scheduling environmentVery complex scheduling environment

Can be thought of as “Network of Queues”Can be thought of as “Network of Queues”

Customers spend most of their time Customers spend most of their time waitingwaiting

Closely related to MRP (See chapter 16)Closely related to MRP (See chapter 16)

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Gantt ChartingGantt Charting

Developed by Henry Gantt in 1917Developed by Henry Gantt in 1917

Related concepts:Related concepts:– Make spanMake span– Machine utilizationMachine utilization

ExampleExample

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Finite Capacity SchedulingFinite Capacity Scheduling

AssumptionsAssumptions

ProcedureProcedure

ExampleExample

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Theory of Constraints (TOC)Theory of Constraints (TOC)

The GoalThe Goal (Goldratt)(Goldratt)

New look at “New look at “InventoryInventory”, “”, “ThroughputThroughput” and ” and ““OperatingOperating ExpensesExpenses””

Definition of “Definition of “Theory of ConstraintsTheory of Constraints””

The concept of “The concept of “bottleneckbottleneck””

Implications of TOC for schedulingImplications of TOC for scheduling

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Dispatching RulesDispatching Rules

MINPRTMINPRT (Minimum Processing Time)(Minimum Processing Time)

MINSOPMINSOP (Minimum Slack time per Operation)(Minimum Slack time per Operation)

FCFSFCFS (First Come, First Served)(First Come, First Served)

MINSDMINSD (Minimum Planned Start Date)(Minimum Planned Start Date)

MINDDMINDD (Minimum Due Date)(Minimum Due Date)

RANDOMRANDOM (Random Selection)(Random Selection)

MINPRTMINPRT withwith TruncationTruncation

CriticalCritical RatioRatio

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Planning and Control SystemsPlanning and Control Systems

What delivery date do I promise?What delivery date do I promise?

How much capacity do I need?How much capacity do I need?

When should I start on each particular When should I start on each particular activity or task?activity or task?

How do I make sure that the job is How do I make sure that the job is completed on time?completed on time?

Advanced Planning & Scheduling (APS)Advanced Planning & Scheduling (APS)