Investigation Station: Science Laboratory - Software - Model It

Investigation Station

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TUTORIAL

I. What is Model-It?
II. Installing Model-It
     A. From a CD
           1. PC
           2. Macintosh
     B. From the web
III. Model-It Tutorial
     A. Acid Rain: Content Information
     B. Introduction to Model-It
          1. Running and Getting Started
          2. Getting familiar with Model-It
     C. Objects
          1. Deciding on Objects
          2. Creating Objects
              a. Using an image in a file
              b. Using an image from Object Palette
     D. Factors
          1. Deciding on Factors
          2. Creating factors
               a. Adding a Factor in the "Plan" stage
               b. Adding a Factor in the "Build" stage
     E. Relationships
          1. Determining and constructing relationships
     F. Testing the Model
          1. Using the Meters
          2. Running the simulation
     G. Saving and Opening Models
          1. Different ways to save your model
          2. Opening a saved model

Factors

Deciding on Factors

As stated, all Objects need to have measurable traits. These measurable traits are called Factors.

All Objects should have Factors associated with them. From the Acid Rain information, four Objects were
selected: Factory, Atmosphere, Animals, and Plants. What measurable Factors can be associated with each of
these Objects?

Based upon the Acid Rain information, the following Factors can be associated with the Object Factory:
    1. Amount of Sulfur dioxide emitted
    2. Amount of Nitrogen dioxide emitted
    3. Hardness of the coal burned
    4. Amount of scrubbers in smokestacks
    5. Circumference of the smokestack

Based upon the Acid Rain information, the following Factors can be associated with the Object Atmosphere:
    1. ph of the rain
    2. Amount of moisture in the air
    3. Amount of air pollution
    4. Amount of Sulfuric acid
    5. Amount of Nitric acid

Based upon the Acid Rain information, the following Factors can be associated with the Object Animals:
    1. Amount of Salmon
    2. Amount of Salmon prey
    3. Amount of Salmon predators

Based upon the Acid Rain information, the following Factors can be associated with the Object Plants:
    1. Amount of Wheat
    2. Amount of Barley
    3. Amount of Cotton
    4. Amount of Oats

Notice that now the Build mode is also available to use. If you select this mode from the menu, you will see that the workspace is currently blank. This is because the Build mode does not display individual objects, but only Factors on objects. Switch back to the Plan mode to continue

Back to Menu

Creating Factors

There are two ways to create a Factor: from Plan mode or Build mode:

Adding a Factor in the "Plan" stage

To create our first Factor, Model Builder needs to be in Plan mode. (Double-check the mode Menu at the upper left corner to be sure that Plan is selected. You should be able to see the objects you have already created.) Click on the NEW FACTOR button located on the left-hand side in the Plan Tools panel underneath the NEW OBJECT button.

Amount of Sulfur Dioxide Emitted will be the first factor created for this model. After clicking on NEW FACTOR, the Factor Editor will appear. The first step is to choose which Object the Factor is associated with. Pull down the Object box by clicking on the down arrow, and click FACTORY.

Next name the Factor by deleting new factor in the Factor text box by using the backspace or delete key.
Type, "Amount of Sulfur Dioxide Emitted."

Next, decide which values the Factor will take on. Are they numerical or some text description? For this Factor the view box is should be set to Text.

The current scale is set to high, medium, and low. Clicking on high, medium, or low and then typing in the new term into the change value box that looks like the image below:

For this Factor, replace the word "high" with "A lot", replace the word "medium" with "Some", and replace the word "low" with "None".

The Initial Value can be set by dragging the arrow on the vertical bar. Set the Initial Value for this Factor to "Some" by dragging the arrow on the bar to "Some".

Finally, type a sentence in the description box that tells what the Factor is. For this Factor, type, "This is the amount of Sulfur Dioxide that Factories emit when they burn coal." Finally click the OK button.

Now, the first factor has been created. You can see in the Plan workspace that the Factory Object now is labeled above with "1 Factor."

The next factor to he created is "Acidity of Rain." Click the NEW FACTOR button, and choose the Object which it is associated with, "Atmosphere."

Next, type the name of the Factor in the Factor text box, "Acidity of Rain." Because acidity is measured in
the Numerical pH scale, change the View setting to "Number."

In the units text box, type "pH." Now change the Number Range. In the lowest text box that says "0", erase the "0" by clicking on "0". When the Change Value box appears type "1",, because the pH scale begins at one. The highest value the pH scale can assume is fourteen, so change the highest text box from to "14."
Next, change the Initial Value text box from "14" to "7", which is neutral pH, meaning it is not acidic nor basic by dragging the arrow until initial value changes to 7.

Now type a description for the Factor. Type, "This is the pH of the rain that falls in the community."

Finally, click on the OK button to save the Factor.

Back to Menu

Adding a Factor in the "Build" stage

From the mode menu in the upper left corner, change the current mode to "Build." Your screen should look similar to the one below:

Under the Build Tools menu, you can see that there are three available tools: Move, Factor, and Relationship. The Move Tool under the Build Tools pane on the left-hand side of the screen can be clicked if the Factors need to be moved. After clicking the Move Tool, click on the Factor you want to move, hold the mouse button down, and drag it to the desired location and then release the mouse button.

The Factor Tool under the Build Tools pane on the left-hand side of the screen can be clicked if any Factors need to be changed, added, or deleted. After clicking the Factor Tool, click on an existing Factor in which you want to delete or to change some information. If we clicked the Factor tool and then clicked on Factory: Amount of Sulfur Dioxide Emitted the Factor editor will pop up it should look like the image below. We can change the information the same way that we did above. If information for an existing Factor needs to be changed, cannot be done in the Plan mode. All changes must occur in the Build mode. To delete click the "Delete Factor" Button otherwise click OK to save any changes that were made.

Make sure that the Factor Tool is still selected. On any blank area of the workspace, click the mouse once. The Factor Editor will appear, just the same as in the Plan mode.

Follow these steps to create the third Factor:

1. Choose which Object the Factor is associated with. In this case, choose Factory.
2. Type the name of the Factor. In this case, type "Hardness of Coal."
3. Decide whether the Factor should be measured by a Text Description or a Numerical Scale and Click either Text or Number in
the menu pull down box. In this case, choose Text.
4. Fill in the Units on the Scale appropriately. In this case, type "Hard, Medium, and Soft".
5. Type a Description of the Factor. In this case, type, "This represents the Hardness of the Coal that is burned in the Factories
in our community."
6. Click on the OK button to save the Factor.

You should now have three different Factors, similar to the example below:

This model currently has only three of the seventeen Factors mentioned earlier; but this is sufficient to demonstrate the next phase of the model building process.

Back to Menu

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