Ba 333 operations management
This presentation is the property of its rightful owner.
Sponsored Links
1 / 82

BA 333 Operations Management PowerPoint PPT Presentation


  • 80 Views
  • Uploaded on
  • Presentation posted in: General

BA 333 Operations Management. Project Management PERT/CPM Spring, 1998. Lecture Outline. Project Management Introduction Definition & Background Components event activity critical path PERT/CPM. Introduction to Project Management. Definition

Download Presentation

BA 333 Operations Management

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Ba 333 operations management

BA 333Operations Management

Project Management

PERT/CPM

Spring, 1998


Lecture outline

Lecture Outline

  • Project Management Introduction

    • Definition & Background

    • Components

      • event

      • activity

      • critical path

    • PERT/CPM


Introduction to project management

Introduction to Project Management

  • Definition

    • to plan, implement, and control the management of large, one time projects

  • Used in Construction, Shipbuilding, Weapons Systems Development, etc.

    • Applies to uncertain technology projects

    • Applies to variable cost resource allocation

  • History of PERT/CPM - Navy/Booze Allen Hamilton Consultants


Introduction to project scheduling

Introduction to Project Scheduling


Components of project control systems

Components of Project Control Systems

  • Predecessor was Gantt Charts

    • Horizontal Bar Charts - Time Lines

    • Tasks

    • Milestones

  • Flow Charts - Relationships Among All Tasks

    • Activities (tasks that take time and resources)

      • sequential vs. concurrent

    • Events (an accomplishment occurring at a specific point in time)


Project characteristics

Project Characteristics

  • Single unit

  • Many related activities

  • Difficult production planning & inventory control

  • General purpose equipment

  • High labor skills


Examples of projects

Examples of Projects


Examples of projects1

Examples of Projects

  • Building construction



© 1995 Corel Corp.


Examples of projects2

Examples of Projects

  • Building construction

  • New product introduction

New! Improved!

19 · Nude Sandalfoot

Medium to Tall (B)

No nonsense

Sheer to waist pantyhose

© 1995 Corel Corp.


Examples of projects3

Examples of Projects

  • Building construction

  • New product introduction

  • Training seminar

© 1995 Corel Corp.


Examples of projects4

Examples of Projects

  • Building construction

  • New product introduction

  • Training seminar

  • Research project

© 1995 Corel Corp.


Project management activities

Project Management Activities


Project management activities1

Project Management Activities


Project management activities2

Project Management Activities

  • Planning

    • Objectives

    • Resources

    • Work break-down sched.

    • Organization


Project management activities3

Project Management Activities

  • Planning

    • Objectives

    • Resources

    • Work break-down sched.

    • Organization

  • Scheduling

    • Project activities

    • Start & end times

    • Network


Project management activities4

Project Management Activities

  • Planning

    • Objectives

    • Resources

    • Work break-down sched.

    • Organization

  • Scheduling

    • Project activities

    • Start & end times

    • Network

  • Controlling

    • Monitor, compare, revise, action


Project planning

Project Planning


Project planning1

Project Planning

  • Establishing objectives

  • Defining project

  • Creating work breakdown structure

  • Determining resources

  • Forming organization

© 1995 Corel Corp.


Project organization

Project Organization

  • Often temporary structure

  • Uses specialists from entire company

  • Headed by project manager

    • Coordinates activities

    • Monitors schedule & costs

  • Permanent structure called ‘matrix organization’

Eng.

Eng.

Mkt.

Acct.

Mgr.

© 1995 Corel Corp.


Project scheduling

Project Scheduling


Project scheduling1

Project Scheduling

  • Sequencing activities

  • Identifying precedence relationships

  • Determining activity times & costs

  • Estimating material & worker requirements

  • Determining critical activities

PERT

J

Test

J

M

A

Build

M

F

Month

Design

J

Activity

© 1995 Corel Corp.


Project scheduling techniques

Project Scheduling Techniques

  • Gantt chart

  • Critical Path Method (CPM)

  • Program Evaluation & Review Technique (PERT)

© 1984-1994 T/Maker Co.


Gantt chart

Gantt Chart


Gantt chart1

Gantt Chart


Pert cpm

PERT & CPM

  • Network techniques

  • Developed in 1950’s

    • CPM by DuPont for chemical plants

    • PERT by U.S. Navy for Polaris missile

  • Consider precedence relationships & interdependencies

  • Each uses a different estimate of activity times


Questions answered by pert cpm

Questions Answered by PERT & CPM

  • Completion date?

  • On schedule? Within budget?

  • Probability of completing by ...?

  • Critical activities?

  • Enough resources available?

  • How can the project be finished early at the least cost?


Pert cpm steps

PERT & CPM Steps

  • Identify activities

  • Determine sequence

  • Create network

  • Determine activity times

  • Find critical path

    • Earliest & latest start times

    • Earliest & latest finish times

    • Slack


Constructing networks

Constructing Networks


Graphical representation of events and activities

Graphical Representation of Events and Activities

  • Flow Charting - Uses Nodes and Arrows

  • Arrows

    • An arrow leads from tail to head directionally

  • Nodes

    • A node is represented by a circle

Arrow

Node


Activity on node

1

2

3

Activity On Node

  • Task is Represented by Node as the Completion of an Activity

  • Arrows Represent the Sequential Linkages Between Activities

  • For Example, Node 1 is Begin, Node 2 is Complete Task 1, Node 3 is Complete Task 2


Activity on arrow

1

2

Activity On Arrow

  • Task is Represented by an Arrow Bounded on Either End by a Node (Event)

  • Each Event is Identified by a Number

  • The Activity is Designated by the Leading Event Number and the Following Event Number - i.e. Activity 1 - 2


Designating task relationships

1

2

3

2

1

4

3

Designating Task Relationships

  • Sequential vs. Concurrent Activities

Sequential Task Relationship

Concurrent Task Relationships


Designating dummy activities

Designating “DUMMY” Activities

  • Represented by Dashed Arrows

  • Show Sequential Relationships Among Tasks, but Take No time or Resources

2

1

4

Dummy Activity 2-3

indicates that both

Activities 1-2 and 2-3 must

be Completed before

beginning Activity 3-4

3


Network terms

Network Terms


Network terms1

Network Terms

Project: Obtain a college degree (B.S.)


Network terms2

Network Terms

Project: Obtain a college degree (B.S.)

Register

1


Network terms3

Network Terms

Project: Obtain a college degree (B.S.)

Register

1

Event (Node)


Network terms4

Network Terms

Project: Obtain a college degree (B.S.)

Register

Attend class, study etc.

1

4 Years

Event (Node)


Network terms5

Network Terms

Project: Obtain a college degree (B.S.)

Register

Attend class, study etc.

1

4 Years

Activity (Arrow)

Event (Node)


Network terms6

Network Terms

Project: Obtain a college degree (B.S.)

Receive diploma

Register

Attend class, study etc.

1

2

4 Years

Activity (Arrow)

Event (Node)

Event (Node)


Activity relationships

Activity Relationships


Activity relationships1

Activity Relationships

1


Activity relationships2

Activity Relationships

2

A

1

3

B

A & B can occur concurrently


Activity relationships3

Activity Relationships

A must be done before C & D can begin

2

D

A

C

1

4

3

B


Activity relationships4

Activity Relationships

2

D

A

C

1

4

3

B

E

B & C must be done before E can begin


Dummy activities

Dummy Activities

  • Activities are defined often by beginning & ending events

    • Example: Activity 2-3

  • Every activity must have unique pair of beginning & ending events

    • Computer programs get confused

  • Dummy activities maintain precedence

    • Consume no time or resources


Dummy activities example

Dummy Activities Example


Dummy activities example1

Dummy Activities Example

2-3

Incorrect

1-2

3-4

1

2

3

4

2-3


Dummy activities example2

Dummy Activities Example

2-3

Incorrect

1-2

3-4

1

2

3

4

2-3

Different activities; same designation


Dummy activities example3

Dummy Activities Example

2-3

Incorrect

1-2

3-4

1

2

3

4

2-3

Correct

1-2

2-4

4-5

4

1

2

5

3

2-3

3-4: Dummy activity


Network diagramming

Network Diagramming

  • First Step in Project Management

  • Begins with a Work Breakdown

    • Lists the “WHAT’ of a Project

    • Begins with Finished Project

    • Consists of Tree Chart, with Each Branch Listing the “WHAT’s” at that Level

  • Then List Each Task that Must Be Completed to Accomplish the “WHAT”


Example work breakdown

Example Work Breakdown

House

Site Prep

Masonry

Carpentry

Finishing

Exterior

Walls

Footings

Piers

Chimney

Forms

Removed

Concrete

Poured

Mixed

Concrete

Forms Laid


Listing of activities

Listing Of Activities

  • Follows the “WHAT” with List of “HOW”

  • Each “WHAT” Results in Detailed List of the “Specific” Tasks Necessary to Accomplish the “WHAT”

  • Followed by Specification of Sequential and Concurrent Relationships Among Tasks

  • Results in Network Flow Diagram Representing the Tasks and Their Relationships


Activity time estimates

Activity Time Estimates

  • CPM - One Time Estimate per Activity

  • PERT - Three Time Estimates per Activity

    • a = Optimistic Time Estimate

    • m = Most Likely Time Estimate

    • b = Pessimistic Time Estimate

  • Can Calculate Activity Mean Time Estimate and Variance


Pert time estimates

PERT Time Estimates

  • Activity Mean Time Estimate = te

  • Activity Variance Estimate = Sigmae

  • te = (a + 4m + b)/6

  • Sigmae = (b - a)/6

Can Use Central Limit Theorem to Estimate Project Time


Example network flow diagram

2

5

4

7

1

6

3

Example Network Flow Diagram

D

A

G

C

I

H

E

B

J

F


Example activity characteristics

Activity

a

m

b

te

Sigmae

Example Activity Characteristics

  • A1-2101214122/3

  • B1-391113112/3

  • C2-4131145/3

  • D2-518974/3

  • E3-4171376/3

  • F3-651015105/3

  • G4-581318135/3

  • H4-6171989/3

  • I5-661020117/3

  • J6-761014104/3


Example network flow diagram1

2

5

4

7

1

6

3

Example Network Flow Diagram

te=7

te=12

te=13

te=11

te=4

te=8

te=7

te=10

te=11

te=10


Early start early finish

Early Start & Early Finish

  • The Early Start Time for an Activity Emanating from an Event is the Earliest Point in Time that an Activity can Begin

    • Determined by the Latest Early Finish of All Activities Terminating in an Event

  • The Early Finish for an Activity is the Sum of its Early Start Time and its te


Example network flow diagram2

2

5

4

7

1

6

3

Example Network Flow Diagram

ES=12

ES=31

te=7

te=12

ES=18

ES=52

te=4

te=11

ES=0

te=13

te=8

ES=42

ES=11

te=7

te=10

te=11

te=10


Late start late finish

Late Start & Late Finish

  • The Late Finish Time for an Activity Terminating in an Event is the Point in Time that it can be Completed Without Delaying the Completion of the Project

    • Determined by Assigning to the LF the Value of the Earliest LS of all Activities Emanating from the Event

  • The Late Start for an Activity is it Late Finish minus its te


Example activity characteristics1

Example Activity Characteristics

a

m

b

te

Sigmae

ES

LS

EF

LF

  • 1-2101214122/3021214

  • 1-391113112/3001111

  • 2-4131145/312141618

  • 2-518974/312241931

  • 3-4171376/311111818

  • 3-651015105/311322142

  • 4-581318135/318183131

  • 4-6171989/318342642

  • 5-661020117/331314242

  • 6-761014104/3424252 52


Example network flow diagram with critical path

Example Network Flow DiagramWith Critical Path

ES|LS|EF|LF

t2-5=7

12|24|19|31

2

5

t1-2=12

0|2|12|14

t5-6=11

31|31|42|42

t4-5=13

18|18|31|31

t2-4=4

12|14|16|18

t4-6=8

18|34 |26|42

4

7

1

t3-4=7

11|11|18|18

t1-3=11

0|0|11|11

t6-7=10

42|42|52|52

6

3

t3-6=10

11|32|21|42


Slack

SLACK

  • Total Slack

    • The Length of Delay in an Activity that Won’t Delay the Completion of the Project - LF- EF or LS-ES

  • Free Slack

    • The Length of Delay in an Activity that Won’t Delay the Beginning of Another Activity

  • Critical Path

    • Activities with the Minimum Total Slack - Often Total Slack on Critical Path Activities = 0


Probabilistic estimates

Probabilistic Estimates

  • Use of te and Sigmae Allows One to Make Probabilistic Estimates of Completion Dates

  • By Summing the te‘s of the Activities on the Critical Path You Can Estimate the Duration of the Entire Project

  • By Summing the Variance (Sigmae2) of the Activities on the Critical Path, You Can estimate the Total Variance of the Critical Path and Make One-Sided Interval Estimates of Project Completion Times


Probabilistic estimates example

Probabilistic Estimates Example

m

a

b

te

Sigmae

(Sigmae)2

  • 1-391113112/34/9

  • 3-4171376/336/9

  • 4-581318135/325/9

  • 5-661020117/349/9

  • 6-761014104/316/9

Variance = 130/9 = 14.4

Std Dev = 3.8

Probability that the Project Duration is Less than 60 days = Pr(T<60)

Same as the Probability that Z < (60-52)/3.8 = 2.1

Therefore: Pr(T<60) = Pr(Z<2.1) = 0.98214 (see App. A, H&R, p. 842)


Pert probability example

PERT Probability Example

You’re a project planner for General Dynamics. A submarine project has an expected completion time of 40 weeks, with a standard deviation of 5 weeks. What is the probability of finishing the sub in 50 weeks or less?

© 1995 Corel Corp.


Converting to standardized variable

Converting to Standardized Variable


Converting to standardized variable1

Converting to Standardized Variable

Assume project completion time follows a normal distribution.


Converting to standardized variable2

Converting to Standardized Variable

Assume project completion time follows a normal distribution.

Normal Distribution


Converting to standardized variable3

Converting to Standardized Variable

Normal Distribution

Standardized Normal Distribution


Converting to standardized variable4

Converting to Standardized Variable

Normal Distribution

Standardized Normal Distribution


Obtaining the probability

Obtaining the Probability


Obtaining the probability1

Obtaining the Probability

Standardized Normal Probability Table (Portion)

Probabilities in body


Obtaining the probability2

Obtaining the Probability

Standardized Normal Probability Table (Portion)

.97725

Probabilities in body


Critical path method

Critical Path Method

  • Uses Deterministic Time Estimates for Activities

  • Also Estimates Cost of Resources Levels for Each Activity

  • Generally You Can increase the Resource Commitment and Reduce the Time Estimate for and Activity

  • Use CPM to Analyze How To Reduce the Critical Path Most Efficiently


Benefits limitations of pert cpm

Benefits & Limitations of PERT/CPM


Benefits of pert cpm

Benefits of PERT/CPM

  • Useful at many stages of project management

  • Mathematically simple

  • Use graphical displays

  • Give critical path & slack time

  • Provide project documentation

  • Useful in monitoring costs


Limitations of pert cpm

Limitations of PERT/CPM

  • Clearly defined, independent, & stable activities

  • Specified precedence relationships

  • Activity times (PERT) follow beta distribution

  • Subjective time estimates

  • Over emphasis on critical path


Conclusion

Conclusion

  • Explained what a project is

  • Summarized the 3 main project management activities

  • Drew project networks

  • Compared PERT & CPM

  • Determined slack & critical path

  • Computed project probabilities


Ba 333 operations management1

BA 333Operations Management

Project Management

PERT/CPM

Spring, 1998

THE END


  • Login