Introduction

This tool mentor describes how to develop and maintain the Trade Study held in DOORS®.

Open the Trade Study

Open the Trade Study.

Create content for introductory section (Section 1)

Follow the guidance in the module to populate the introductory section.

1. Set the view to "01 - Guidance"
2. Create content in the introductory sections as indicated by the Guidance column.

Create Key System Function Entries

Create objects in the specification to define the Key System Functions.

1. Open the Trade Study (if not already open).
2. Set the view in the Trade Study to "01 - Guidance "
3. For each Key System Function identified, create necessary entries within Section 2 in the Trade Study.
   1. The easiest way of doing this is to copy the example section (with hierarchy) and rename the heading to identify the relevant function.
   2. If you edit or copy the objects with "Replace Text" from these sections, the requirements that you create will have the appropriate default attribute values.
4. Create the necessary traceability

Create Solution Candidates for each Key System Function

Create objects in the Trade Study for each Solution Candidate for each Key System Function.

1. Open the Trade Study (if not already open).
2. For each Key System Function:
3. 1. Enter the identified Solution Candidates
   2. Create entries for each of these. The easiest way of doing this is to copy the example section (with hierarchy) and rename the heading to identify the relevant solution candidate.

Create Assessment Criteria for each Key System Function

Create objects in the Trade Study for each Assessment Criterion for each Key System Function.

1. Open the Trade Study (if not already open).
2. Set the View to "02 – Criteria attributes"
3. For each Key System Function:
   1. Enter the identified Assessment Criteria
   2. Create entries for each of these. The easiest way of doing this is to copy the example section (with hierarchy) and rename the heading to identify the relevant solution candidate. Describe the criterion in the child objects
   3. Enter the assigned weight for each Assessment Criterion in the Weight attribute for the Criterion heading. The sum of the weights for all the criteria for one function should be normalized to 1.0
   4. Enter the utility curve for each Assessment Criterion in the "Utility curve" attribute for the heading. This curve should be described in the form of points, each defined as pairs <criterion value, utility>, where utility is in the range [0.0, 10.0]

Enter Measures of Effectiveness

Enter Measures of Effectiveness for each Solution Candidate for each Assessment Criterion for each Key System Function.

1. Open the Trade Study (if not already open).
2. Set the View to "02 – Criteria attributes"
3. For each Key Function, ensure that there is a column for each Solution Candidate, inserting new columns if necessary (Table → Insert → Column → To the Right)
4. For each Key Function, for each Assessment Criterion identified:
5. 1. Create a new row for the Criterion, if necessary (Table → Insert → Row → Below)
   2. Calculate the MoE for each Solution Candidate by converting the measured value for the criterion for that candidate into a utility (using the utility curve), then multiply that by the weighting for the criterion
   3. Enter the calculated MoE value for each Solution Candidate into the appropriate table cell
6. For each Solution Candidate, calculate the total value by adding the calculated MoEs and put this value into the Total row at the bottom of the table

Enter Recommendations

1. Open the Trade Study (if not already open).
2. Enter the recommendations in Section 3.

Create Traceability

Traceability to System Use-Case Blocks

Create traceability from each Key System Function in the Trade Study to the relevant information in the Executable Use-Case Model.

1. Open the Trade Study (if not already open).
2. Set the View to "03 – Associated System Use Cases"
3. Open the Executable Use-Case Model
4. Set the view to "02 – Associated Trade Study Items"
5. For each Key System Function create links to relevant System Use Case Blocks:

Traceability from Subsystem Blocks

Create traceability from Subsystem Blocks in the System Architectural Model to the relevant information in the Trade Study.

1. Open the Trade Study (if not already open).
2. Set the View to "04 - Associated Subsystem Elements"
3. Open the System Architectural Model
4. Set the view to "02 - Associated Trade Study Elements"
5. For each Key System Function create links from the relevant Subsystem Block: