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GPE engineering project management

Project Management in an Engineering

Context

SOW CHARTER SCOPE DEFINITION

PM

WBS

circulation, negotiation, translation

WP à activities ----- estimation Time Cost

GANTT PERT AOA AON

Network diagrams in context

-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐-‐ planning, resource alloca7on, cost alloca7on, control -‐-‐-‐-‐-‐-‐-‐-‐-‐-‐

WBS

Mainly PMBOK chapter 6

Network diagrams

WBS

PERT, what does it state

for? They are like WBS?

PERT – Program Evalua/on & Review Technique

WBS GANTT

PERT

Network Analysis (PERT – Program Evalua/on & Review Technique; CPM – Cri/cal Path Method)

Network modula7on approach used in planning, scheduling and controlling projects. Beyond the analysis they facilitate, they represent a common ground to discuss op7ons so they are excellent communica7on tools. They facilitate thema7c brain-‐storming analysis

Network diagrams are en7ty/rela7onship models (interrela7ons among instances of resources) usually used in project planning, namely on scheduling and 7me management

Using these models we need to take into account:

•  interrela7on of ac7vi7es (sequencing rela7ons) and •  rela7ons among ac7vi7es and resources (alloca7on)

There are more complex models, using sta7s7cs but we will eventually address them later

Cri7cal Path Method (CPM) (determinis7c) A schedule network analysis technique used to determine the amount of scheduling flexibility (the amount of float) on various logical network paths in the project schedule network, and to determine the minimum total project dura7on. Early dates are calculated by means of a forward pass, using a specified start date. Late dates are calculated by means of a backward pass, star7ng from a specified comple7on date, which some7mes is the project early finish date calculated during the forward pass calcula7on. Program Evalua7on and Review Technique (PERT) (probabilis7c) A technique used to improve the accuracy of the cost or dura7on es7mates of project components when there is uncertainty. PERT uses weighted averages of op7mis7c, pessimis7c, and most likely es7mates (the well-‐known three-‐point es7mates) of the components' cost or dura7on. Different weigh7ng schemes represent different probability distribu7ons of the possible cost or dura7on of a component. For instance, the typical formula is [(op/mis/c + 4 /mes the most likely + pessimis/c) divided by 6], approximates a beta distribu7on.

CPM/PERT •  Cri7cal Path Method (CPM)

–  DuPont & Remington-‐Rand (1956)

–  Determinis7c task 7mes

–  Ac7vity-‐on-‐node network construc7on

•  Project Evalua7on and Review Technique (PERT)

–  US Navy, Booz, Allen & Hamilton –  Mul7ple task 7me es7mates (probabilis7c)

–  Ac7vity-‐on-‐arrow network construc7on

PERT elements Events (states), ac7vi7es (nature and 7me), preceding, alloca7on, context (context must always be defined and clarified) Some examples of PERT representa7on -‐ AOA – ac7vity on arrow, or ADM -‐ arrow diagramming method; and AON – ac7vity on node

A,3 B,5

E,6

C,7

D,2

F,3 G,10

PERT elements Events (states), ac7vi7es (nature and 7me), preceding, alloca7on, context (context must always be defined and clarified) Some examples of PERT representa7on -‐ AOA – ac7vity on arrow, or ADM -‐ arrow diagramming method; and AON – ac7vity on node

A,3 B,5

E,6

C,7

D,2

F,3 G,10

17 19

Examples of different nota/ons

Parallel ac/vi/es signaled as we exemplify are not allowed

A

B

A,B

A

B dummy

If you fail this notation in the exam you will have “0” in the entire question

Task B can only be started acer ac7vity A is completed. The same with D and C

A,3 B,7

C,4 D,6

10

10

A,3 B,7

C,4 D,6

Network Analysis example AOA

There is a dummy ac7vity – dura7on 0 (only a logical dependency)

A,3 B,7

C,4 D,6

10

10

Are all paths iden7fied?


A,3 B,7

C,4 D,6

10

10

No, there are three paths, not two! And that makes quite a difference!!

11


A,3 B,7

C,4 D,6

10

10

11


(A,B)

(C,B)

(C,D)

Instant time - 5 Time interval - 6

A,3 B,7

C,4 D,6

10

10

11

Activity Duration Early St Early Fi Latest St Lat. Fi. Float

A B C D

Dummy


A,3 B,7

C,4 D,6

10

10

11

Activity Duration Early St Early Fi Latest St Lat. Fi. Float

A 3 0 3 1 4 1 B 7 4 11 4 11 0 C 4 0 4 0 4 0 D 6 4 10 5 11 1

Dummy 0 4 4 4 4 0


Instant times

PERTS, and projects 1.  Define the project and all its ac7vi7es. The project is made of tasks and all tasks should have a

single start and a single finish

2.  Develop the rela7onships among the ac7vi7es. Decide which ac7vi7es must precede, which must follow others, and the ones that can be executed in parallel. If you are short in 7me try to put in parallel as much ac7vi7es as you can

3.  Draw the network diagram connec7ng all the ac7vi7es. Each ac7vity is unique. Dummy ac7vi7es are immaterial in 7me but relevant in sequence, they impose logical dependences

4.  You can assign 7me and cost to each ac7vity

5.  Compute the longest 7me path through the network. This path is called the Cri/cal Path

6.  Use the network to help plan, schedule, monitor and control the project and also as a communica7on tool

Preceded by a planning effort by the project management team. This planning effort is part of the Develop Project Manage- ment Plan process

documented in the schedule management plan

PERTS, and projects

WBS GANTT PERT

backward pass Early dates are calculated forwards, using the forward path. Late dates are calculated in reverse direc7on, star7ng at the date of the finishing of the project – this is the backward path

In this example one backward path leads us to “event 3” through ac7vity B. So we have: •  Total project 7me (cri7cal path) = 11 •  11-‐7 = 4. This means that the late start for ac7vity B is 4

Rela7ng to “event 2” we have to evaluate two paths, Dummy and D. Through Dummy we have 4 -‐ 0 = 4, this means that Dummy late start is 4 and through D we have 11 -‐ 6 = 5, so ac7vity D late start is 5

A,3

C,4 D,6

B,7

2

3

4 DUMMY,0

Activity

Duration

Early St

Early Fi

Latest St

Lat. Fi.

Float

A 3 0 3 1 4 1 B 7 4 11 4 11 0 C 4 0 4 0 4 0 D 6 4 10 5 11 1

Dummy

0 4 4 4 4 0

Late start and backward path

So you already have the rule to compute early starts and late starts. Early starts are computed in the forward path from the beginning to the end, adding dura7on and late starts are computed in the backwards path, subtrac7ng dura7on from the end Project management tools compute this for you, you just have to manage according to situated condi7ons (environment, resources, risk, …)

Your project is to design and develop an electric motor. Ac7vity dura7ons and predecessors are iden7fied at the following table. A) construct a PERT AOA; B) Which is the dura7on of every path? Which path is the cri7cal one? C) What happens if ac/vity E dura/on becomes 8?

Ac7vity dura7on predecessor

A 10 -‐

B 20 -‐

C 4 -‐

D 2 A

E 10 B,C

F 8 B,C

G 4 B,C

H 2 C

I 6 G,H

J 2 D,E


A 10 -‐

B 20 -‐

C 4 -‐

D 2 A

E 10 B,C

F 8 B,C

G 4 B,C

H 2 C

I 6 G,H

J 2 D,E



A 10 -‐

B 20 -‐

C 4 -‐

D 2 A

E 10 B,C

F 8 B,C

G 4 B,C

H 2 C

I 6 G,H

J 2 D,E


8 paths

CP


A 10 -‐

B 20 -‐

C 4 -‐

D 2 A

E 10 B,C

F 8 B,C

G 4 B,C

H 2 C

I 6 G,H

J 2 D,E


8 paths

CP CP

30

E from 10 to 8:

14

A,3 B,7

C,4 D,6

Network Analysis example AOA à AON

A,3 B,7

C,4 D,6 With AON you don’t have dummies

END BEGIN

AOA

AON


A 10 -‐

B 20 -‐

C 4 -‐

D 2 A

E 10 B,C

F 8 B,C

G 4 B,C

H 2 C

I 6 G,H

J 2 D,E A,10

B,20

C,4

D,2

E,10

F,8

G,4

H,2

I,6

J,2

B

END

Network Analysis example AON

ADJ 14 BEJ 32 BF 28 BGI 30 CEJ 16 CF 12 CGI 14 CHI 12

gpe - autenticação · b dummy if you fail this notation in the exam you will have “0” in the...

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