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www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons





www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 2

 


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!!
on what?
on what?
why
why


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how
how


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who
who



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www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 3
&


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##(###
##(###


#
#
#$%#)
#$%#)
* +#,#-#).)/

0%#(
0%#(



Risk
identification
Risk
assessment

Risk
control
##.
##.



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,)
1#
-##/.
#$
(,
(,
www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 4
#$#
www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 5


$#$$#
$#$$#
*
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* $#
*
3$##

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* $#

3$#$
3$#$
* 7$#
*
)$#
* )$#
www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 6
$#2

).
).

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$)$#
$)$#
-

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3$#
3$#


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#)
#)


#
#
-/
-/

{
O
O, Dom } |= not

obstruction

{
O
O, Dom } |≠ false domain consistency
8
3
#$$$)feasibility
 G: TrainStoppedAtBlockSignal
If
If StopSignal
Dom:
If
If TrainStopsAtStopSignal
then
then DriverResponsive

O: Driver
Un
Unresponsive

9$)1#
9$)1#


$$)-
$$)-
)
)
#/
#/
www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 7
$#

7.$#$#
7.$#$#
{not O
1
, , not O
n
, Dom } |=

domain completeness



If

If
not
not DriverUnresponsive
and
and
not
not BrakeSystemDown
and
and StopSignal

then
then TrainStoppedAtBlockSignal

$4##
$4##

$$$((($:
$$$((($:

3$##)
3$##)
www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 8
3$####
#+
#+

Hazard
Hazard
$#$#
$#$#

Safety
Safety



Threat
Threat
$#$#
$#$#
Security
Security





Disclosure, Corruption, DenialOfService,

Inaccuracy
Inaccuracy
$#$#
$#$#
Accuracy
Accuracy



Misinformation
Misinformation
$#$#

$#$#
Information
Information



NonInformation, WrongInformation, TooLateInformation,

Dissatisfaction
Dissatisfaction
$#$#
$#$#
Satisfaction
Satisfaction



NonSatisfaction, PartialSatisfaction, TooLateSatisfaction,

Unusability
Unusability
$#$#
$#$#
Usability
Usability






Us
ability
Convenience
Goal
Functional goal
Non-functional goal
Quality of service
Compliance
Architectural
Development
Confident
i
ality
Integrity
Availability
Distribution
Installation
Safety
Security
Performance
Reliability
Maintainability
Cost
Time
Space
Deadline
Variability
Software
interoperability
Interface

User
interaction
Device
interaction
Satisfaction
Information
Stim-Response
Accuracy
Cost
www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 9


$#$$#
$#$$#
*
$#2
* $#
*
3$##

$#
$#
*
3$#
*
3$#
* 4$#564
* $#

3$#$

3$#$
* 7$#
*
)$#
* )$#
www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 10
3$#56;3

#
#
-/
-/
*

'not

* $#


56
564.
3
34#
*

$#$..
obstruction
TrainStoppedAtBlockEntry
If StopSignal
StopSignal And

Not TrainStoppedAtBlockEntry
SignalNotVisible
DriverUnresponsive
BrakeSystemDown

root obstacle
OR-refinement
ResponsivenessCheck
SentRegularly
resolution
countermeasure goal
obstacle
www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 11
3$#56;3-</
MobilizedAmbulance
AtIncidentInTime
MobilizedAmbulance Not
AtIncidentInTime
AmbulanceLost
AmbulanceStopped
TrafficDeviation

AmbulanceCrew
NotInFamiliarArea
AND-refinement
In-carGPS
NotWorking

www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 12
3$#


56
56
4$#
4$#
3
3
$
$
*
#{subO
1
, , subO
n
, Dom } |=
3
*
#{subO
1
, , subO
n
, Dom } |≠ false
*
{subO
1
, , subO
j-1
, subO
j+1
, , subO

n
, Dom } |=
3

3
3
4$#
4$#
3
3
$
$
*
{subO
i
, Dom } |=
3
*
4#{subO
i
, Dom } |≠ false
*
4#{not subO
1
, , not subO
n
, Dom } |= not
3
*
%{subO

i
, subO
j
, Dom } |= false

7
7


subO
subO
i
i
34
34
3
3






3
3
$#
$#











subO
subO
i
i
$#
$#




www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 13
3$#$4
564

6=(
6=(
not
not
-!
-!
and
and
</

</
,)
,)
not
not
!
!
or not
or not
<
<
'>
)
#,#
#,#$##$
4)$#
G
propagated
obstruction
G1
G2
not G1
not G2

not G
www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 14
$#
Obstacle DriverUnresponsive
Def Situation of a train driver failing to react to a command
and take appropriate action according to that command

? FormalSpec in temporal logic for analysis,
not
not in this chapter @
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www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 15
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www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 16
3$#
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(#$#
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www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 17
3$#$
(

Goal model
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data dependency
Obstacle
identification
Obstacle
assessment
Obstacle
resolution

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* ##$#,#

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##2
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www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 18
7$#
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Obstacle
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www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 19
7$#
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#34(
#34(

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4##)
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www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 20
7$#$4$
MotorReversed Iff MovingOnRunway
MotorReversed
Iff WheelsTurning
MovingOnRunway
Iff WheelsTurning
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7$#$4$
NOT
MovingOnRunway
Iff WheelsTurning
NOT

MotorReversed
Iff WheelsTurning
$#
MotorReversed Iff MovingOnRunway
MotorReversed
Iff WheelsTurning
MovingOnRunway
Iff WheelsTurning
www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 22
7$#$4$
NOT
MovingOnRunway
Iff WheelsTurning
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MotorReversed
Iff WheelsTurning
MotorReversed
AndNot
WheelsTurning
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WheelsTurning
AndNot
MotorReversed
MovingOnRunway
AndNot
WheelsTurning
WheelsTurning
AndNot

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MotorReversed Iff MovingOnRunway
MotorReversed
Iff WheelsTurning
MovingOnRunway
Iff WheelsTurning
www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 23
7$#$4$
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NOT
MotorReversed
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AndNot
WheelsTurning
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
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WheelsTurning
AndNot
MotorReversed
MovingOnRunway
AndNot
WheelsTurning
WheelsTurning
AndNot

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WheelsNotOut
WheelsBroken
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MotorReversed Iff MovingOnRunway
MotorReversed
Iff WheelsTurning
MovingOnRunway
Iff WheelsTurning
www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 24
3$##1
BrakeReleased ↔ DriverWantsToStart
BrakeReleased
↔ MotorRaising
MotorRaising ↔
AccelerPedalPressed
AccelerPedalPressed
↔ DriverWantsToStart
www.wileyeurope .com/college/van lamsweerde Chap.9: Risk Analysis on Goal Models © 2009 John Wiley and Sons 25
MotorRaising And Not
AccelerPedalPressed
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3$##1
BrakeReleased ↔ DriverWantsToStart
BrakeReleased
↔ MotorRaising
MotorRaising ↔

AccelerPedalPressed
AccelerPedalPressed
↔ DriverWantsToStart
AccelerPedalPressed
And Not DriverWantsToStart

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