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The sample process "Eliciting requirements of a Recycling Machine" is about a method for designing the requirements of recycling facilities. The recycling facilities are meant for customers of a supermarket. The adequate method is obtained though instantiation of the meta-process model on the process model.
The following table displays the stepwise trace of the process to elicit requirements for the recycling machine (from <ref name="Rolland 1999" /> ):
{| class="wikitable"
|- valign=top
<table border=0 cellspacing=5 cellpadding=0>
! Step
<tr>
! Guideline
<td valign=top> '''Step'''</td>
! Meta-process
<td valign=top> '''Guideline'''</td>
! Process
<td valign=top> '''Meta-process'''</td>
! Product (Goal = Gxx)
<td valign=top> '''Process'''</td>
<td|- valign=top> '''Product (Goal = Gxx)'''</td>
| 1.1
</tr>
| SSG-4
<tr>
| Choose section with select strategy
<td valign=top> 1.1</td>
| SSG4 suggests two strategies. The template-driven strategy is chosen because it is the most appropriate way to become familiar with the goal formalisation proposed by the CREWS-L’Ecritoire method
<td valign=top> SSG-4</td>
|
<td valign=top> Choose section with select strategy
|- valign=top
</td>
| 1.2
<td valign=top> SSG4 suggests two strategies. The template-driven strategy is chosen because it is the most appropriate way to become familiar with the goal formalisation proposed by the CREWS-L’Ecritoire method</td>
| IAG-6
<td valign=top> </td>
| Enact section with automated support
</tr>
| IAG6 displays a goal statement template and explains the meaning of each parameter. The requirement Engineer (RE) chooses a loose statement having only a verb and a target
<tr>
| G1: Provideverb (Recycling Facilities*) target *RF
<td valign=top> 1.2</td>
<td|- valign=top> IAG-6</td>
| 2.1
<td valign=top> Enact section with automated support
| ISG-1
</td>
| Choose section with select intention
<td valign=top> IAG6 displays a goal statement template and explains the meaning of each parameter. The requirement Engineer (RE) chooses a loose statement having only a verb and a target </td>
| ISG1 provides RE with arguments to advise him on choosing one of the two possible intentions from ''Elicit a Goal'', namely to ''Elicit a Goal'' or to ''Write a Scenario''. The former is selected so as to generate alternative design solutions
<td valign=top> G1: Provideverb (Recycling Facilities*) target *RF </td>
|
</tr>
|- valign=top
<tr>
| 2.2
<td valign=top> 2.1</td>
| IAG-1
<td valign=top> ISG-1</td>
| <td valign=top> ChooseEnact section with select intentionautomated support
| IAG1 uses the goal statement structure and parameter values supplied to generate alternative goals. This leads to 21 alternative goals to G1 which are ORed to G1. After discussion with stakeholders, G4 is selected
</td>
| G2: Provide bottle RF to our customers with a card-based machine; G3: Provide paper RF to our customers with a card-based machine; G4: Provide bottle and box RR to our customers with a card-based machine; . . . G22: Provide bottle RF to all customers with money return machine
<td valign=top> ISG1 provides RE with arguments to advise him on choosing one of the two possible intentions from ''''Elicit a Goal'''', namely to ''''Elicit a Goal'' ''or to ''''Write a Scenario''''. The former is selected so as to generate alternative design solutions </td>
<td|- valign=top> </td>
| 3.1
</tr>
| SSG-3
<tr>
| Choose section with select strategy
<td valign=top> 2.2</td>
| SSG3 offers two strategies from which the template-driven strategy is chosen. This is because there is uncertainty about what a scenario should be. The templates lead to some certainty
<td valign=top> IAG-1</td>
|
<td valign=top> Enact section with automated support
|- valign=top
</td>
| 3.2
<td valign=top> IAG1 uses the goal statement structure and parameter values supplied to generate alternative goals. This leads to 21 alternative goals to G1 which are ORed to G1. After discussion with stakeholders, G4 is selected </td>
| IAG-7
<td valign=top> G2: Provide bottle RF to our customers with a card-based machine; G3: Provide paper RF to our customers with a card-based machine; G4: Provide bottle and box RR to our customers with a card-based machine; . . . G22: Provide bottle RF to all customers with money return machine </td>
| Enact section with automated support
</tr>
| IAG7 proposes a template to be filled in. The template corresponds to a service scenario and contains actions that express services expected from the system
<tr>
| SC4: If the customer gets a card, he recycles objects
<td valign=top> 3.1</td>
<td|- valign=top> SSG-3</td>
| 4.1
<td valign=top> Choose section with select strategy
| SSG-2
</td>
| Choose section with select strategy
<td valign=top> SSG3 offers two strategies from which the template-driven strategy is chosen. This is because there is uncertainty about what a scenario should be. The templates lead to some certainty </td>
| SSG2 offers two strategies to conceptualise a Scenario. Among the two strategies, manual and computer based, the former is chosen since the service scenario (SC4) is very simple and can be handled manually
<td valign=top> </td>
|
</tr>
|- valign=top
<tr>
| 4.2
<td valign=top> 3.2</td>
| IAG-10
<td valign=top> IAG-7</td>
<td valign=top>| Enact section with automated support
| IAG10 suggests two things: (1) to avoid anaphoric references such as he, she, etc. (2) to express atomic actions in an explicit ordering (3) to avoid ambiguities The scenario is rewritten accordingly
</td>
| SC4: 1. The customer gets a card; 2. The customer recycles boxes and bottles
<td valign=top> IAG7 proposes a template to be filled in. The template corresponds to a service scenario and contains actions that express services expected from the system </td>
|- valign=top
<td valign=top> SC4: If the customer gets a card, he recycles objects </td>
| 5.1
</tr>
| SSG-1
<tr>
| Choose section with select strategy
<td valign=top> 4.1</td>
| The RE knows that he wants to analyse the scenario SC4 to discover a new goal. Thus, he knows the target intention ‘Elicit a Goal’ and SSG1 is displayed. SSG1 offers three strategies to discover new goals from scenario analysis. The refinement strategy, is chosen because there is a need to discover the functional requirements of recycling machine
<td valign=top> SSG-2</td>
|
<td valign=top> Choose section with select strategy
|- valign=top
</td>
| 5.2
<td valign=top> SSG2 offers two strategies to conceptualise a Scenario. Among the two strategies, manual and computer based, the former is chosen since the service scenario (SC4) is very simple and can be handled manually</td>
| IAG-4
<td valign=top> </td>
| Enact section with automated support
</tr>
| IAG4 guides in transforming actions of the service scenario SC4 into goals which express functional requirements. Two goals are generated and related together to G4 with an AND relationship. G24 is selected for further processing
<tr>
| G23: Get card from supermarket; G24: Recycle bottles and boxes from RM
<td valign=top> 4.2</td>
<td|- valign=top> IAG-10</td>
| 6.1
<td valign=top> Enact section with automated support
| SSG-3
</td>
| Choose section with select strategy
<td valign=top> IAG10 suggests two things: (1) to avoid anaphoric references such as he, she, etc. (2) to express atomic actions in an explicit ordering (3) to avoid ambiguities The scenario is rewritten accordingly </td>
| The RE knows his target intention, namely ‘Write a Scenario’. Thus SSG3 is displayed to help the RE in selecting the right strategy. The free prose strategy is selected because the text is likely to be long and the free prose facilitates this
<td valign=top> SC4: 1. The customer gets a card; 2. The customer recycles boxes and bottles </td>
|
</tr>
|- valign=top
<tr>
| 6.2
<td valign=top> 5.1</td>
| IAG-8
<td valign=top> SSG-1</td>
| <td valign=top> ChooseEnact section with select strategyautomated support
| IAG8 provides style and contents guidelines adapted to the type of scenario at hand, namely system interaction scenario
</td>
| SC24-1: The customer inserts his card in the RM. The RM checks if the card is valid and then a prompt is given. The customer inputs the bottles and/or boxes in the RM. If the objects are not blocked, the RM ejects the card and prints a receipt
<td valign=top> The RE knows that he wants to analyse the scenario SC4 to discover a new goal. Thus, he knows the target intention ‘Elicit a Goal’ and SSG1 is displayed. SSG1 offers three strategies to discover new goals from scenario analysis. The refinement strategy, is chosen because there is a need to discover the functional requirements of recycling machine </td>
<td|- valign=top> </td>
| 7.1
</tr>
| SSG-2
<tr>
| Choose section with select strategy
<td valign=top> 5.2</td>
| SSG2 is displayed. The automated support strategy is selected to take advantage of the powerful linguistic devices and obtain a scenario formulation which will be the basis for automated reasoning
<td valign=top> IAG-4</td>
|
<td valign=top> Enact section with automated support
|- valign=top
</td>
| 7.2
<td valign=top> IAG4 guides in transforming actions of the service scenario SC4 into goals which express functional requirements. Two goals are generated and related together to G4 with an AND relationship. G24 is selected for further processing </td>
| IAG-9
<td valign=top> G23: Get card from supermarket; G24: Recycle bottles and boxes from RM </td>
| Enact section with automated support
</tr>
| IAG9 semi-automatically transforms the initial prose into a structured text whose semantics conform to the scenario model. The transformation includes disambiguation, completion and mapping onto the linguistic structures associated to the concepts of the scenario model. SC24-2 is the result of the transformation of SC24-1. (Underlined statements result of the transformation)
<tr>
| SC24-2: 1. The customer inserts the customer card in the RM, 2. The RM checks if the card is valid, 3. If the card is valid, 4. A prompt is given to the customer, 5. The customer inputs the bottles and the boxes in the RM, 6. The RM checks if the bottles and the boxes are not blocked, 7. If the bottles and the boxes are not blocked, 8. The RM ejects the card to the customer, 9. The RM prints a receipt to the customer
<td valign=top> 6.1</td>
<td|- valign=top> SSG-3</td>
| 8.1
<td valign=top> Choose section with select strategy
| SSG-1
</td>
| Choose section with select strategy
<td valign=top> The RE knows his target intention, namely ‘Write a Scenario’. Thus SSG3 is displayed to help the RE in selecting the right strategy. The free prose strategy is selected because the text is likely to be long and the free prose facilitates this </td>
| Of the three strategies proposed by SSG1, the alternative discovery strategy is chosen. This strategy suits the need to investigate variations and exceptions of the normal course of actions described in SC242
<td valign=top> </td>
|
</tr>
|- valign=top
<tr>
| 8.2
<td valign=top> 6.2</td>
| IAG-3
<td valign=top> IAG-8</td>
<td valign=top>| Enact section with automated support
| IAG3 proposes several tactics to discover alternative goals to G24. The one based on the analysis of conditions in the scenario is selected. This leads to discover G25 and G26
</td>
| G25: Recycle box and bottles from RM with invalid card; G26: Recycle box and bottles with a deblocking phase
<td valign=top> IAG8 provides style and contents guidelines adapted to the type of scenario at hand, namely system interaction scenario </td>
|}
<td valign=top> SC24-1: The customer inserts his card in the RM. The RM checks if the card is valid and then a prompt is given. The customer inputs the bottles and/or boxes in the RM. If the objects are not blocked, the RM ejects the card and prints a receipt
</td>
</tr>
<tr>
<td valign=top> 7.1</td>
<td valign=top> SSG-2</td>
<td valign=top> Choose section with select strategy
</td>
<td valign=top> SSG2 is displayed. The automated support strategy is selected to take advantage of the powerful linguistic devices and obtain a scenario formulation which will be the basis for automated reasoning </td>
<td valign=top> </td>
</tr>
<tr>
<td valign=top> 7.2</td>
<td valign=top> IAG-9</td>
<td valign=top> Enact section with automated support
</td>
<td valign=top> IAG9 semi-automatically transforms the initial prose into a structured text whose semantics conform to the scenario model. The transformation includes disambiguation, completion and mapping onto the linguistic structures associated to the concepts of the scenario model. SC24-2 is the result of the transformation of SC24-1. (Underlined statements result of the transformation) </td>
<td valign=top> SC24-2: 1. The customer inserts the customer card in the RM, 2. The RM checks if the card is valid, 3. If the card is valid, 4. A prompt is given to the customer, 5. The customer inputs the bottles and the boxes in the RM, 6. The RM checks if the bottles and the boxes are not blocked, 7. If the bottles and the boxes are not blocked, 8. The RM ejects the card to the customer, 9. The RM prints a receipt to the customer</td>
</tr>
<tr>
<td valign=top> 8.1</td>
<td valign=top> SSG-1</td>
<td valign=top> Choose section with select strategy
</td>
<td valign=top> Of the three strategies proposed by SSG1, the alternative discovery strategy is chosen. This strategy suits the need to investigate variations and exceptions of the normal course of actions described in SC242 </td>
<td valign=top> </td>
</tr>
<tr>
<td valign=top> 8.2</td>
<td valign=top> IAG-3</td>
<td valign=top> Enact section with automated support
</td>
<td valign=top> IAG3 proposes several tactics to discover alternative goals to G24. The one based on the analysis of conditions in the scenario is selected. This leads to discover G25 and G26 </td>
<td valign=top> G25: Recycle box and bottles from RM with invalid card; G26: Recycle box and bottles with a deblocking phase </td>
</tr>
</table>
== See also ==
| 