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• Include the following two entities as children of Hull:

Entity

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The user will be asked to provide input values in entity Main Dimensions for the following parameters:

2.3.2.1     Creation of parameters

Right click in the right field of the Knowledge Browser and select “New Parameter/function..”, see Figure 49, which opens the Parameter, Object, Function or Document window.

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Figure 49: Include new parameter

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Figure 50: New parameter, object, function or document window

You can type a name in the window and select whether it is a Value, String, Object, Function or a Document. Type in here “Loa” andselect Value. Please note a valid name should not contain special characters and spaces. The created parameter “Loa” is placed in the Knowledge Browser with a red cross behind.

When you have experience with creating Quaestor knowledge bases (see Knowledge engineering getting started course Part 1 (PDF document) and the Tutorials on Quaestor basics ) you will know that a parameter should always have a unique name, dimension and the system should “know” how to determine the value of the parameter.

So, the properly define the parameter(s) select “Loa” in the Knowledge Browser and provide a dimension in the dimension field of the Frame Viewer, see Figure 33, in this case meter “m”. Furthermore provide a reference text in field 5 of the Frame Viewer as explanation for the user of your knowledge base, for example “Length over all”. Be sure that the reference/radio button is switched to the reference mode. Finally you can indicate that “Loa” will only requested to the user and will not be determined by a relation. Select inthe Slots & Properties window “VR: User only” in the “Determined by” field.

A special remark has to be made concerning the “Determined by” field for use with Taxonomies. When you are sure that parameters should be requested as input, change the “Determined by” field to VR. When you add an Entity-relation or connect a relation to a parameter (see section2.3.3.2 below) leave the “Determined by” field to “USR” or “USL”. Quaestor will make sure the added or connected relation is used and the red cross for the parameter will disappear the moment the relation is added or connected.

In the same way you have to include the VR parameters “Lpp”, “Boa” and “Dm” in the Knowledge Browser.

2.3.2.2     Create classes to order your knowledge

You can create tree nodes in the Knowledge Browser, in order to group parameters, objects and relations. This is only a way to order your knowledge and has no functional meaning during the use of knowledge.

Right click on the “Top Goals/Undefined” node in the tree of the Knowledge Browser and select New Class. Now you can define a name in the window that will appear, see Figure 51. For example the class node name “Dimensions” where we can put our created parameters from above.

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Figure 51: Create nodes in the class tree

You can use a point to create sub-classes. Thus, typing “Test. Example” gives Figure 52.

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Figure 52: Make sub classes by using a point

When you have created the classes you want, you can simply drag and drop the parameters and/or relations to the desired class.

2.3.2.3     Including parameters in an Entity

Now we have created parameters in the Knowledge Browser. The next step is to include these parameters in Entity “Main Dimensions”. Two ways are available to include parameters in an Entity:

1. Include parameters by a drag/drop action between Knowledge Browser and Workbase.
2. Use option “include parameters from knowledge base” while creating a new Entity.

The first method is to include parameters in an Entity with the drag/drop functionality from the Knowledge Browser into the Workbase. This method will be explained by including the parameter “Loa” in the Entity “Main Dimensions”.

Select the Entity “Main Dimensions” in the Workbase to put the focus in the Workbase on the content of this Entity. Then you have toselect the parameter “Loa” in the Knowledge Browser, hold the left mouse button and move the mouse to parameter list of the Entity “Main Dimensions” in the Workbase, see Figure 53. Now the Entity “Main Dimensions” contains the parameter “Loa”.

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Figure 53: Include parameters in an Entity with drag drop functionality

Do the same for “Lpp”, “Boa” and “Dm”, see Figure 54.

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Figure 54: Parameters included in Entity "Main Dimensions"

The second method to include parameters in an Entity is by means of the select option “include parameters from knowledge base” while in the Entity Editor. After closing the Entity Editor Quaestor presents a list of parameters that are defined in the knowledge base. All selected parameters will be included in the newly created Entity. This is especially convenient when a lot of parameters are already available in the knowledge base the moment you create a particular Entity.

2.3.2.4     Affect presentation sequence of parameters

It can be desirable to affect the sequence of parameters presented in the Workbase list during a dialogue. Normally Quaestor presents parameters in an alphabetical sequence. An @ORDER attribute in the Data Slot of a parameter defines the relative position of a parameter in the Workbase list. Define this position by: @ORDER:RelativePosition, in which RelativePosition is an integer. The higher the value of RelativePosition, the later the value is placed in the list. The @ORDER values of parameters to be presented need not to be subsequent values. Parameters are sorted on RelativePosition. Values with no @ORDER attribute are placed behind parameters with the @ORDER attribute.

We will explain this option only by placing parameter “Loa” at the top of the list. It is up to you to order the other parameters. First select parameter “Loa” in the right field of the Knowledge Browser and switch the radio button of the Frame Viewer to the data mode. In here you have to type “@ORDER:1”, see Figure 55 and Figure 56.

Please note figures in this tutorial can present the sequence of parameters different in comparison with your knowledge base. In that case probably parameters are ordered with @ORDER attributes. It is up to you to do the same.

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Figure 55: Order parameters with @ORDER attribute in Data Slot of parameter

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Figure 56: Loa on top of the list because of @ORDER: 1 in Data Slot of parameter

2.3.3      Entity “Hydrostatics”

Create the following parameters (all are values) within the Knowledge Browser.

The parameters “Cb”, “Rho” and “T_design” will be user input so select for these parameters in the Slots & Properties window “VR: User only” in the “Determined by” field.

As mentioned above, for the other parameters you do not have to change the “Determined by” field. Leave these parameters as USRbecause we are going to create Entity relations for these parameters.

Next drag and drop the parameters: “Lpp”, “Boa”, “Cb”, “Displacement”, “Rho”, “T_design” and “Volume” from the Knowledge Browser into the Entity “Hydrostatics”, see Figure 57.

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Figure 57: Include parameters in Entity "Hydrostatics"

2.3.3.1     Create drop down box for parameter Rho

Because we want to provide only two options for parameter “Rho” (1.025 or 1.000 [t/m³]), it is useful to create a dropdown box. This can be done by providing the reference text as indicated in Figure 58 in the Frame Viewer. (This is also why the table above showed this as reference text for Rho).

To present 3 decimals places for parameter “Rho” during a dialogue change the number of decimals places into 3 in the Slots & Properties of parameter “Rho”, see Figure 59.

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Figure 58: Create a drop down box in reference of parameter Rho

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Figure 59: Adapt decimal places in the Slots & Properties of parameter Rho

Please note that you can create additional class nodes to order your parameters in the knowledge browser, see 2.3.2.2 Create classes.

2.3.3.2     Create Entity relations

In the “Hydrostatics” Entity we want to perform calculations based on information from “Main Dimensions” and some relation. In order to achieve this, we have to create so called Entity-relations. The first Entity-relation to create is for parameter “Boa” in Entity “Hydrostatics”: the value of “Boa” in Entity “Hydrostatics” should be equal to the value of “Boa” in Entity “Main Dimensions”.

First select the parameter “Boa” in Entity “Hydrostatics” in the Workbase. Move your mouse outside the input field and Select the right mouse button menu Taxonomy>Choose/create relation or press Ctrl+T (please note that you should right click on the right side of the input field in order to initiate the right mouse menu. When you right click above the selected input field, you will get a small menu with undo, copy, paste, etc. which is meant for copy/paste of values in this field).

After this action The Expression Editor will appear, see Figure 60.

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Figure 60: Create expression with Expression Editor

Providing a relation in the Expression Editor (upper part of the editor) will add a relation to the system, which is only valid in Entity “Hydrostatics”.

Because the most common action of an Entity-relation is to refer to other Entities (see also paragraph 2.3.4 below), the expression editor for Entity relations start with the ENTITY#() function already placed by default at the right hand side of the expression. If you do not want to use this function you can always delete it.

By providing the unique and correct QEntityId within the ENTITY#() function, you can refer to information in other Entities. We want to refer to information in “Main Dimensions”. For that we have to know the unique QEntityId.

There are two ways to get this ID:

1. Look-up the ID by browsing to the Entity and read the QEntityId: The QEntityId of Entity “Main Dimensions” is 12. Figure 53 shows that QEntityId = 12 for Entity “Main Dimensions”.
2. When you are in the expression editor, press on your keyboard the right arrow to initiate a “walk through” menu to navigate through all Entity levels in your Taxonomy (showing QEntityNames). See the sequence for “Main Dimensions” below.

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Figure 61: Cursor on the right side, first Entity will show. Press right arrow:

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Figure 62: Next level inside previous selected Entity, select an Entity (up/down arrow) and press the right arrow:

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Figure 63: Next Entity level, press right arrow

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Figure 64: Next level inside previous selected Entity, select an Entity (up/down arrow) and press the right arrow:

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Figure 65: Next level inside previous selected Entity, select an Entity and press enter to get the QEntityId.

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Figure 66: The QEntityId is selected.

Please note that the value of QEntityID of Entity “Main Dimensions” as presented in this tutorial could differ  from your knowledge base, because it depends on the sequence in which you have created Entities in a Taxonomy Entity tree!

So, Quaestor returns QEntityNames of Entity objects at the moment you start within the Entity#() function (method 2). This functionality supports the Knowledge Engineer by searching for the right QEntityID. After selecting the ID (press enter after selecting the relevant Entity), placing the closing bracket and placing the dot, Quaestor will show all available parameters in the selected Entity. With the cursors you can scroll to the correct parameter and press enter to select the parameter.

In this way we have to write and save the following relation:

• Boa = ENTITY#(12).Boa

This means “Boa” is equal to the “Boa” of the Entity with QEntityID = 12.

Hereafter the cell colour of “Boa” in “Hydrostatics” has turned to yellow. So, cells of parameters with relations in Entities are coloured yellow. To reset the parameter back to an input value, select this parameter in the Workbase and select the right mouse button menu Taxonomy>Value = Input or Ctrl+T.

To edit an encapsulated relation, select in the Workbase this parameter and select the right mouse button menu Taxonomy>Edit relation or Ctrl+M.

Please note that the Entity relation is something special. When you have experience with creating Quaestor knowledge bases (see the Tutorials on Quaestor basics ) you will know that normally, relation will be visible in the Knowledge Browser. Entity-relations however, will only be visible when you select the parameter in the Entity of the taxonomy tree. Furthermore, these type of relations are shown with a new Entity relation icon:Image Removed. See also paragraph 2.3.4 below.

Create the Entity relation for “Lpp” in Entity “Hydrostatics” in the same with. This parameter must be equal to the value of “Lpp” in Entity “Main Dimensions”:

• Lpp = ENTITY#(12).Lpp

Finally we will provide relation to calculate “Displacement” and “Volume” in Entity “Hydrostatics”. The following calculation should be made:

• Displacement    = Cb*Lpp*Boa*T_design*Rho
• Volume             = Cb*Lpp*Boa*T_design

Note that these relations can be created in two ways:

1. Add the relations to the Taxonomy as already done for the other parameters using the mouse button menu Taxonomy>Choose/create relation or Ctrl+T. Now you will have to delete the ENTITY#() function and add the expression. Or,
2. Add the relations to the Knowledge Browser and include these for the parameters in an Entity.

The second method is very convenient when you know that the particular relation might be used (connected) in several Entities. By adding the relation to the Knowledge Browser, you can connect is several times to different parameters in different Entities, saving a lot of time. See also paragraph 2.3.4 below.

Create “Volume” using the first method. The second method will be used for parameter “Displacement”, which is explained below.

2.3.3.3     Connect relation in Knowledge Browser to a parameter in an Entity

Start with creating one or more relations in the Knowledge Browser.

Select parameter “Displacement” in the right window of the Knowledge Browser, then right click, and select option “New relation...”(or CTRL + N). The Expression Editor opens and you can type the expression “Displacement = Cb*Lpp*Boa*T_design*Rho”. In this way the relation is added to the knowledge base (and not only to the Entity in the Taxonomy). However, realise that it is not yet connected to the parameter in the Entity of your Taxonomy.

To connect the relation, in the Workbase select the parameter “Displacement” in Entity ‘Hydrostatics”. Then, select the right mouse button menu Taxonomy>Choose/create relation or press Ctrl+T. A window will open showing the available relations for the selected parameter in the Knowledge Browser.

You can browse through the available relations and select the relation you want to use to compute the parameter, see Figure 67. In this case select the relation you have just created. The same method can be used to include any available relation for any selected parameter.

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Figure 67: Include relation from Knowledge Browser in Entity

Furthermore, please note that it is still possible to create a new taxonomy relation by selecting the first option in presented window.

2.3.3.4     Provide the possibility to enable users to modify calculated values

In the first part of the tutorial, with parameter “Volume”, it was shown that it is possible to enable the user to modify calculated values after they are determined by the system. We can enable this functionality by adding a @MODIFY attribute to the data slot of the parameter.

First select parameter “Volume” in the right field of the Knowledge Browser and switch the radio button of the Frame Viewer to the data mode. In here you have to type @MODIFY, see Figure 68.

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Figure 68: Provide parameter "Volume" with a @MODIFY attribute

2.3.3.5     Define minimum and maximum values for parameters

Another interesting feature to assist the user is providing feedback about minimum and maximum input values. Moreover, you could make these boundaries into hard ranges in order to protect the user against providing value that might cause faulty results.

As an example we want to define a minimum and a maximum for the parameter “Cb”. This value must be between 0 – 1.0 [-].The system should issue a warning if the computed or input value is not within the indicated boundaries. This is done by means of the attributes @MAXVAL and @MINVAL.

When you want to make sure that this range cannot be superseded you also have to add the attribute @HARDRANGE.

Thus, the following attributes have to be added to the parameter “Cb” (how to add attributes to a parameter is described in 2.3.3.4.):

@MAXVAL:1.0
@MINVAL:0
@HARDRANGE

2.3.3.6     Show computed values during the dialogue

To show computed values during a dialogue you have to include the standard Quaestor parameter “QEntityData” (with the drag and drop functionality) from the Knowledge Browser in Entity “Hydrostatics”. You will find the parameter by either typing its name in the search box of the Knowledge Browser (field 1 of Figure 32). Or go to the top node of the tree in the Knowledge Browser (with the name of your knowledge base) and search in the list on the right side.

After dragging and dropping the parameter to the Entity, write “@SHOW” within the value of this parameter. Now, computed values in this Entity will always be shown during a dialogue. Figure 69 presents the result for Entity “Hydrostatics”.

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Figure 69: Entity "Hydrostatics" in taxonomy

2.3.4      Strategy for adding relations in taxonomy type of knowledge bases

Before we continue with the next Entity, we want to give more insight in the creation of relations in taxonomy type of knowledge bases. In the previous paragraph you have noticed that we created Entity-relations, paragraph 2.3.3.2 above and “normal” relations, paragraph 2.3.3.3 above. But why do we have two different methods?

You have three ways of adding and using relations:

1. Adding an Entity relation to the Entity in a Taxonomy;
2. Add a relation to the Knowledge Browser and connect it to a parameter in an Entity;
3. Create a relation in the Knowledge Browser and let the modeler determine which relations to use to determine a parameter in an Entity. This is only facilitated when all parameters in the Entity will be determined by the modeler.

Three important remarks can be made about the use of the different relation types:

1. The general approach is to create Entity relations when you are developing a Taxonomy type of knowledge base. 
   Only used normal relations when you want to use the modeling/reasoning functionality of Quaestor. You might want to use the modeler when you want to execute complex models which make use of reasoning an advantage over a normal traditional fully hardcoded model (which a Taxonomy is to some extent). This is the case when you want the structure (network of relations) of a model to be dependent on the choices made and input provided by the user.
2. The main reason to use normal relations and connecting them to parameters in an Entity is when you know that the relation will be used on multiple positions in the Taxonomy. In that case you rather create one relation and connect it to the parameters in the relevant Entities.
3. Use the ENTITY# function only in combination with Entity relations. You can use this function in normal relations but this is not advisable. The reason for use only in Entity relations is that, in case of an Entity relations, the EntityID in the ENTITY# function will be renumbered when modifications are made to the Taxonomy that cause Entities to be renumbered. This renumbering in the relation will not take place for normal relations.

2.3.5      Entity “Reference planes”

First create the following Entities as a child of Entity “Reference planes”.

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2.3.6      Entity “Transverse planes”

We want to create the possibility for the user to define a table containing a number of transverse reference planes. In section 4.6 of the first part of the tutorial, the goal for Entity “Transverse planes” is described in detail.

For each plane the user has to define a position and a name.

First create the following parameters in the Knowledge Browser. Please note that “Name$” is a string parameter and not a value.

The parameters “Nr”, “Name$”, “Frame_Nr” and “Frame_spacing” will be determined by “VR: User only” (indicate “VR” in Slots & Properties of parameter).

Now drag and drop the parameters in “Transverse planes“: “Nr”, “Name$”, “CaseID”, “X”, “Frame_Nr” and “Frame_spacing”.

Figure 70 shows all parameters in Entity “Transverse planes”.

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Figure 70: Parameters in Entity Transverse planes

2.3.6.1     Let a parameter change the number of cases in an Entity

We will use parameter “Nr” to indicate the number of cases (columns) in an Entity.

Provide parameter “Nr” with the special attribute @NRINST in the Data Slot of the parameter. The @NRINST attribute tells Quaestor that the value given/calculated for this parameter indicates the number of instances/cases in an object (in this case an Entity).

Furthermore it is useful to provide “Nr” also with the attribute @INTEGER, see Figure 71. The @INTEGER attribute limits input or computed values of the parameter to integer values. If other than integer values are either computed or provided, the system issues a warning and prompts for other input or for other input of the related input.

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Figure 71: Nr parameter, indicates number of instances within Entity

Moreover, for integer value you could also change the number of decimal places to 0.

2.3.6.2     Force parameters to show in the table (make parameters multi case)

Normally, any single (constant) value is placed in the list view, see Figure 4.

The @MULTVAL attribute forces single value parameter to present itself in the table of an Object/Entity. The @MULTVAL attribute is used in parameters if you wish to obtain a table which includes all values of these parameters whether they are single (constant) values or not. Figure 17 in chapter 4.6 of the first part shows an example.

We want the following parameters to be shown in the table: “Name$”, “CaseID”, “Frame_Nr” and “X”. So you have to provide @MULTVAL attribute in the Data Slot of these four parameters. By doing this you can see the location of these parameters are moved from list view to table view (you might have to force Quaestor to review the Workbase by switch between Entities). Please notice the differences between Figure 70 and Figure 72.

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Figure 72: Parameters with @MULTVAL attribute in Entity Transverse planes

2.3.6.3     Relation for X position of transverse reference plane

Select parameter “X” in Entity “Transverse planes” in the Workbase. Select the right mouse button menu Taxonomy>Choose/create relation or press Ctrl+T. Create the following relation:

• X = Frame_nr * (Frame_spacing/1000)

For each case, representing a transverse reference plane, this relation will be calculated. Parameter “Frame_spacing” does not contain a @MULTVAL attribute, thus the value provided for “Frame_spacing” will be constant for each case.

2.3.6.4     Provide default values

It is possible to provide a proposed default value for “Frame_spacing” in the solution that can be overruled by the user by simply providing this value for the parameter in the Entity. For example, type 700 in the value cell of Frame_spacing”.

2.3.6.5     Use of ORCA() function to calculate numbers for each case: CaseID

Select parameter “CaseID” in Entity “Transverse planes” in the Workbase. Select the right mouse button menu Taxonomy>Choose/create relation or press Ctrl+T. Create the following relation:

• CaseID = ORCA(1)

The function ORCA(1) returns the current case number which is now being executed. Later on we will use this calculated value to refer to one of these transverse reference planes.

Please note that you also could have made a relation in the Knowledge Browser and connect it to the parameter (the second method for Entity relations, see 2.3.3.2) because you will use the same relation for the horizontal reference planes.

2.3.6.6     Include standard Quaestor parameters: QEntityData, QEntityDoc and QEntityRef to illustrate and describe the Entity

Include (with the drag and drop functionality) from the Knowledge Browser the standard Quaestor parameters “QEntityData”,“QEntityDoc” and “QEntityRef” in Entity “Transverse planes”. These parameters will not be visible for users of your knowledge base.

• To show the computed values for this Entity “Transverse planes” during a dialogue write “@SHOW’ behind “QEntityData”.
• You can add a picture in “QEntityDoc”, which explains definitions of reference planes and the coordinate system of the vessel to the user in the Explanation window. 
  Select QEntityDoc in Entity “Transverse planes” and select the right mouse button menu Taxonomy>Include Binary Data orCtrl+B, see Figure 73. Browse to the file you want to include, we propose the provided picture “reference_planes.bmp”.

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Figure 73: Include Binary data in standard Quaestor parameter QEntityDoc

• Comparable to assigning reference to a parameter, you can assign a reference to an Entity. Behind the included “QEntityRef” you can assign an unlimited Entity reference text, which will be shown in the html Explanation window. For example; “Define number of transverse reference planes”

2.3.6.7     Define a Entity specific presentation name for a parameter

You can use a @WBNAME parameter attribute to define a presentation name to the user. For example, you want to define a presentation name “Number of transverse reference planes” for “Nr”.

Because you want this presentation name to be unique within Entity “Transverse planes” you cannot simply add the attribute to the data slot of the parameter.

First you have to select parameter “Nr” in Entity “Transverse planes” and select the right mouse button menu Taxonomy>Instantiate“Nr” (or Ctrl+E). Now for the parameter the textfield is shown yellow in the frame viewer for both the reference and data slot. This means that you are now able to provide a reference text and attributes for the parameter which differs from the global reference text and attributes for this parameter.

You can restore the global settings by doing the same action, but now the option Set global ”Nr” is available instead of Instantiate “Nr”.

After instantiating parameter “Nr” in Entity “Transverse planes” you can provide the following attribute in the Data Slot of the frame viewer; @WBNAME:Number of transverse reference planes. Furthermore you can change locally the reference text for “Nr” which is more applicable to Entity “Transverse planes”. For example, “Number of transverse reference planes” instead of “Number of instances”. Again note the text is written cursive, because you have instantiated the parameter “Nr”.

The same you can perform for parameter “Name$”. First instantiate parameter “Name$” in Entity “Transverse planes” and provide the following attribute in the Data Slot of the frame viewer: @WBNAME: Name of reference plane. Again you can change locally the reference text for “Name$” which is more applicable to Entity “Transverse planes”. For example, “Name of transverse reference plane” instead of “Name of object”.

Please note, you are able to define a presentation sequence of parameters (within a specific Entity) by providing @ORDER attributes forinstantiated parameters. See 2.3.2.4, for the explanation of @ORDER attribute.

Finally Entity “Transverse planes” should more or less look like Figure 74.

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Figure 74: Entity "Transverse planes"

2.3.7      Entity “Horizontal planes”

The explanation for this paragraph will be extensive than the previous, because most of the actions that have to be performed are equal to the actions described above.

The main goal is that we want to create the possibility for the user to define a table with a number of horizontal reference planes. For each plane the user has to define a position and a name.

• First create the following parameter in the Knowledge Browser.

• Provide parameter “Z” also with an attribute @MULTVAL in the Data Slot of the parameter.
• Next include the following parameters in Entity “Horizontal planes“: “Nr”, “Name$”, “CaseID”, “Z”, “QEntityData”, “QEntityDoc”and “QEntityRef”.
• Parameters “Nr”, “Name$” and “Z” will be requested to the user (so all are VR parameters). Instantiate the parameters “Nr” and “Name$” in Entity “Horizontal planes” and provide for both parameters a @WBNAME attribute to define a presentation name for the user.
• Create the following relation CaseID = ORCA(1)
• To show computed values during a dialogue write “@SHOW” behind “QEntityData”.
• Add picture “reference_planes.bmp” as Binary to “QEntityDoc”.
• Assign the following text for “QEntityRef”; “Define number of horizontal reference planes”

Now your developed Entity “Horizontal planes” should more or less look like Figure 75.

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Figure 75: Entity "Horizontal planes"

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Reference planes

• Include the following two entities as children of Reference planes:

Entity “Decks”

Entity “Decks” will be developed as a container which contains combined data of all defined singular decks below. As child of Entity “Decks” we include the multiple (select one of more) Entity “Deck”.

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