Multiple dependency activity on node (AoN) networks

(lecture)

Four possible dependencies between activities

• Finish-to-start (or normal) dependency• Start-to-start dependency• Finish-to-finish dependency• Start-to-finish dependency

Finish-to-start (or normal) dependency

a

0 30

0 33

b

7 90

7 92

4

00

Start-to-start (or lag-start) dependency

x

0 30

0 33

y

4 60

4 62

400

Example: the air-conditioning should be started in a building a given time before visitors are let inside

Finish-to-finish (lag-finish) dependency

c

0 30

0 33

d

5 70

5 72

4

00

Example: c: writing a chapter to a bookd: editing the whole book lag: acceptance of the chapter by the reviewer

Start-to-finish dependency

a

0 60

0 66

b

2 40

2 42

4

00

Example: a: production with a new machineb: quality checklag: to ensure the coverage for the test production with quality checking

Dependencies can be used in combination

Start-to-start & finish-to-finish:

a

0 3?

0 33

b

5 9?

7 92

5

6

??

Example: a: marketing actionb: measuring the effect of the actionlags: the effect needs time to appear, and to fade out

Floats on multiple dependency networks

• Total float = LFT – EST – Duration

• Early total float = LFT – EFT• Late total float = LST – EST

• In case of multiple dependence free float cannot be calculated

Solution

a

0 30

0 33

b

5 92

7 92

5

6

Calculations with finish-to-start lags

a0

0 3

b3

c3

f3

d3

e3

g3

h3

4

3

5

1

2

1 2

Calculations with finish-to-start lags

a0 30

0 33

b6 96

12 153

c7 100

7 103

f20 230

20 233

d4 76

10 133

e15 180

15 183

g18 213

21 243

h24 270

24 273

4

3

5

1

2

1 2

0

0

000

6

6

3

Various dependencies

a0

0 1

b2

c3

f1

d4

e4

g5

h3

4

3

5

1

2

1

2

5

2

Dangler activities!

Various dependencies

a0 10

0 11

b4 613

14 192

c5 80

5 83

f9 1910

19 201

d2 516

18 224

e13 170

13 174

g17 220

17 225

h20 241

21 243

4

3

5

1

2

1

2

5

2

Practicing

a0 40

0 44

b3

d2

c7

e4

5

1

2

3

4

Practicing

a0 40

0 44

b4 79

13 163

d8 109

17 192

c9 160

9 167

e19 230

19 234

5

1

2

3

4

Reading

• Textbook chapter 15

Thank you for listening