GoldSim Dashboard Tips ‘n’ Tricks

Illustrative examples from models for radioactive waste management
John Tauxe, PhD, PE • Tauxian Solutions, LLC
with Jason Lillywhite • GoldSim Technology Group

Designing effective graphical user interfaces (GUIs) makes complex models accessible and interactive. This blog post, based on a poster presentation submitted by John Tauxe of Tauxian Solutions, LLC at the 2024 GoldSim User's Conference, shares practical tips and "tricks" for building powerful GoldSim Dashboards. These strategies are particularly well-suited for applications such as radioactive waste management models, where clear visualization and user flexibility are required. We'll explore various techniques for organizing interactive elements, visualizing model changes, and even implementing workarounds for advanced functionalities to enhance the user experience.

Interactive Dashboards

This section outlines various ways to create an interactive user interface in an organized way, allowing the user to have flexibility and better visualize the changes they are making to the model.

Optimizing Waste Disposal Operations

For a waste disposal landfill, optimizing the placement of incoming materials while monitoring available space and "room" for additional risks promotes efficient use of the disposal resource. Figure 1 illustrates a dashboard designed to assign disposal and candidate wastes to different levels in this Fictitious Waste Facility (FWF).

Various waste placement alternatives can be evaluated in model space with the regulatory goal of reducing long-term risk—keeping doses as low as reasonably achievable (ALARA). This goal naturally comports with the operational goal of maximizing the amount of disposed waste in a given volume.

Figure 1 - Dashboard used to assign disposal and candidate wastes

Refer to Figure 1 for dashboard design ideas described below. The numbers in the descriptions below refer to the numbers in the red circles in the figure.

1. Text Box Controls for Instructions and Documentation: Use text box controls with scroll bars to provide formatted text, ensuring all information is visible regardless of screen resolution. This is ideal for adding documentation or instructions in compact spaces, especially when formatting is needed.
2. Buttons and Check Boxes for Data Input and Operational Flags:
   • Buttons can link to larger data arrays, such as vector or matrix data inputs, which may be too large to display directly on the dashboard.
   • Check boxes are useful for linking to conditional Data elements that act as operational flags. They can assign a scalar Data element to a Boolean or binary choice of values, such as setting a data value to 1 when checked and 0 when unchecked. This 0/1 value is convenient in calculations as a multiplier that, in effect, includes or excludes some process or value. 
     
     
     
3. Result Display Controls for Dynamic Outputs: Arrange result display controls in tables and link them to dynamic model outputs. These controls show results both during and at the conclusion of a simulation. 
   
   
   
4. Plain text controls placed next to these displays can serve as labels to explain the output. For consistent aesthetics, consider using the "Segoe UI" font at size 9 to match the default Result Display control, unlike what was done in these examples. 
   
   
   
5. Consistent Navigation with Buttons: For seamless navigation across multiple dashboards, arrange buttons in the same locations at the bottom of each page. This consistent placement creates the illusion of a single, continuous page, making transitions less jarring for the user.
6. Input Grids for Layer Loading: An input grid linked to a data array allows users to "load" each disposal layer effectively.
7. Thermometers for Visualizing Relative Values: Thermometers can be trimmed to fit into small spaces and are excellent for displaying relative values from multiple linked model outputs. They function similarly to dynamic bar charts, offering adjustable size, colors, and display features to suit specific needs. Here they represent the relative amount of waste filling each layer in the repository. Status Result Displays for Verification: Combine status result displays (e.g., green lights) with result displays to visually confirm that proposed disposal plans are working and layers are not over-filled. 
   
   
   

Selecting Items in Space

This interactive map, for a different waste facility that has many pits rather than layers, allows the user to decide which waste disposal pits to include in the analysis. This site is not considering further disposals, but rather which parts of the site need to be remediated or removed in order to reduce future risks. To aid in identification, especially since pits may be challenging to locate on the map, a coordinated alphabetical list is also provided. Each individual pit item on the dashboard is attached to a conditional Data element, and multiple dashboard controls of this type can be connected to a single element output. These conditional elements are then collected into a vector. Figure 2 illustrates a dashboard for the selection of pits in a section of a facility known as the NDA Special Holes.

Figure 2 - Selection of NDA Special Holes

Enhancing User Selection

To facilitate user interaction and flexibility when selecting items, use the following types of dashboard controls:

1. Combo Boxes for Quick Selection: Implement Combo Boxes to enable quick selection options such as "ALL" or "NONE" of the pits, or a "User-Select" mode. When "ALL" or "NONE" is chosen, the individual user-selected pits are overridden, but their original selection state is preserved. 
   
   
   
2. Paired Check Boxes and Result Status Displays: Pair Check Boxes (indicating the user's direct selection) with Result Status Displays (indicating whether the pit is included in the modeling based on other choices made in the Combo Boxes). This pairing provides visual feedback. It's important to note that the user's selection is only one part of the logic for including a particular pit. There can be multiple levels of nested inclusion, such as "All NDA Facilities," "All Special Holes, West," and finally, the "User’s Request". 
   
   
   

In the above example, the user’s individual pit selection is shown to the left of each pit name, but to the right, the green check box shows that in this instance ALL the pits (or perhaps just ALL the pits in this group) are selected for analysis. The selections are constructed this way so that the user does not have to continually select and deselect pits to make comparisons of ALL vs just some particular ones. This facilitates the fundamental question at this cleanup site about the dose reductions resulting from removing only some pits.

Specifying Locations on a Map

While GoldSim and its Dashboards don't natively support the selection of arbitrary locations directly on a map, a clever workaround involves displaying a map and providing an input table for users to locate well modeling locations at yet another waste facility, known as Area G (See Figure 3). This is needed since regulations require evaluation of the maximum risk from groundwater exposure pathways (in addition to other exposure pathways), yet the location of a hypothetical groundwater supply well corresponding to that maximum risk cannot be determined without running the model. Note that maximum risk or dose may be driven by different radionuclides at different times, adding to the complexity of the problem.

Figure 3 - Control Panel - Area G Groundwater Location Selection

1. Clear Instructions: Instructions for using the map and input table are provided within a Text Box.
2. Integrated Map Display: The map itself is an imported image onto which GoldSim Text elements and drawing elements have been added. These text and drawing elements also serve to provide orientation on the map.
3. A Hyperlink is included to access a PDF document, offering additional background reading for the user.
4. Text and drawing elements provide site orientation.
5. Model Information Display: Text elements and Result Displays, arranged in a table, provide relevant information directly from the model.
6. Coordinate Input Grid: An Input Grid is provided, allowing the user to specify up to eight well locations by entering their corresponding map coordinates. Users must identify these locations on the map and then input the coordinates into the table. By trying out different locations, the model user should be able to identify the approximate location corresponding to the greatest groundwater pathway risk.

Dashboard Workarounds for GoldSim

Below are some workarounds that can be used to allow the model user to iterate multiple runs.

A “Manual” Iterative Calculation

Although GoldSim can iterate to an optimal result, this ability has its limits, as in optimizing an entire vector. This Dashboard includes instructions for the user to perform an iterative calculation. The objective in this analysis is to determine radionuclide-specific limits on waste concentrations that just meet limits of risk. This example site is a Resource Conservation and Recovery Act (RCRA) landfill for (chemically) hazardous wastes that can also accept a limited amount of radioactive waste. The radiological Waste Concentration Limit (WCL) is dose-based, meaning that the dose resulting from any proposed mix of disposed radionuclides must be evaluated against the standard. 

What makes this such a tricky problem is that it is mathematically ill-posed. That is, there is no single best answer, since the same composite dose could be reached with a practically infinite combination of more of one and less of another radionuclide. This is further complicated by the need to account for chains of radioactive decay and ingrowth. In some cases, dose from a decay product may limit the disposal of a parent, for example. This is the purpose of the “RCRA WCL Determination Settings” section in the following Dashboard, wherein the user can identify which member of a decay chain they wish to make a WCL determination for.

Figure 4 - RCRA Landfill Waste Concentration Limit Determination

Figure 4 illustrates the dashboard layout for this process. Key features include:

1. Check boxes and Input Edit boxes allow the user to set the determination mode. You can use control attributes to disable them, depending on the output of another element in the model, which can be controlled by checking a box. Note that since units are not displayed by Input Controls, the modeler must provide the implied units next to each Input Control. Be careful, though, and make sure that these hard-coded text strings do in fact correspond to the units of the Data elements that are linked to these Input Controls.
2. This displays a series of Check Boxes that correspond to a row of pits in the facility, and the posting of values for thickness, area, and volume that are relevant to the calculations. Note that with the "Set clay fill thickness" Check Box being unchecked (see bullet 1), the Input Control next to it is disabled, and the model uses a default clay fill thickness value of 3.82 ft, displayed here in a Result Status Control. If the "Set clay fill thickness" Check Box were checked, this value would display whatever value the user has entered in the adjacent Input Control, which is set to 3 in this example.
3. Use a formatted text box to emphasize certain parts and allow for scrolling in the cases where space is limted.
4. Align combo box controls to fit many controls in a small space and give it more of a table type of view, which is just a handful of controls stacked vertically.
5. Use a Result Status Display to alert user of warnings.
6. Add another Run button to make the iterative workflow easier for the user.

Identifying the Culprit

Result Display Controls in GoldSim allow for displaying a result in up to five different states, using predefined icon sets. The dashboard shown in Figure 5 provides a visual method to identify the receptor most at risk and determine if a radionuclide is at its solubility limit (indicated by a yellow light) or limited by its specific activity (indicated by a green check).

Further information is available through a Tool Tip that appears when hovering over the always-yellow indicator in the column heading. This indicator is simply a dummy Result Status Display that shows yellow whether TRUE or FALSE.

Figure 5 - RCRA Landfill Waste Concentration Limit Determination Results

Each of the displays identifying the maximum exposed receptor is a 2-stage Result Display Control. These controls are linked to items within a conditional Expression, which is structured as a vector of Species for each receptor. Each Expression evaluates all Species to ascertain which receptor faces the greatest risk. 

To manage the display of extensive information, a row of seven elements (comprising six Buttons and one Text element) at the top of the dashboard simulates the graphical user interface concept of tabbed dialog boxes. These elements direct the user to one of seven similar dashboards, effectively addressing the challenge of presenting too much information on a single dashboard.

Testing Model Functions

To verify and evaluate the function of different physical and chemical processes in a model, the user can select/deselect the processes and watch the results displayed on various graphs.

Figure 6 - CT Testing and Diagnostics

Figure 6 is a screen capture of a dashboard designed for this purpose, with key features including:

1. The selection of physical processes through Check Boxes leverages Dashboard Control Attributes. These attributes allow controls to be hidden or presented dynamically, based on the status of other controls. For example, resuspension might be dependent on the state of soil/water partitioning.
2. Result Windows are used to display the presence of I-129 across different media and locations. This enables the user to confirm that a selected process is functioning as expected and that a deselected process is not, serving as a valuable qualitative quality assurance check.
3. Expressions are incorporated to provide simulation information directly within these Result Displays. 
   
   
   

Conclusion

Effective GoldSim Dashboard design enables you to create user-friendly and powerful models, particularly in complex fields like radioactive waste management. As demonstrated through these examples, careful consideration of control types, layout, and interactive features can significantly enhance a model's usability and the clarity of its outputs. From organizing waste disposal to specifying locations on a map and even implementing "manual" iterative calculations, these tips and tricks help you to better visualize changes, interpret results, and interact with the underlying model. By applying these strategies, you can build GoldSim Dashboards that are not only informative but also effective for many different needs. 

You can obtain a PDF version of the presentation here: https://www.tauxian.com