It is rare to have a dispersion modeling project that you start on and finish without any changes during the process. There is almost always a modification to emission rates or an updated design that moves a source or raises or lowers a stack height. Typically, these changes happen when you are 99% completed with the project. There is really nothing you can do about it.
The situation above reminds me of a quote by Bonnie Hammer, “You can’t change how people act, but what you can change is how you react.”
Rather than starting over from scratch each time there is a change, you can prepare for it. By using a database centric approach to dispersion modeling, those preparations can be simple and almost effortless.
Tools for Dispersion Modeling
To properly prepare for anything, you need three things:
- The proper materials;
- The proper tools; and
- A plan to act on.
You have all the materials: model input values, model results, and the listing of files that contain all that information in its raw form. Under the file-based paradigm that most of modelers use, that is where it ends. There are dozens, even hundreds of disconnected text files that you have to sift through to find all the values that were selected as input or were calculated as output and then place all those values into your AQA report. If anything changes, you need to keep track of which files changed and then re-copy and re-paste all those values into your report. Hopefully, you caught all the changes.
The tool that can help is a well-designed database to house all of your model input and output and the means to access and summarize those data to put into your AQA report. Rather than trying to figure out how to design your own model project database from scratch, NaviKnow provides a simple database template to make things easier. To access and download the NaviKnow Access database, go to one of our free mini-courses on Using Databases with Dispersion Modeling: Putting It All Together, Connect Your Modeling Database to Your GIS, or Connect Your Modeling Database to Your AQA. All the courses are free, but you will have to register before you receive access.
Finally, the plan you need is already built into the NaviKnow database. Queries have been constructed to provide the information necessary for you to include in your AQA report. Careful thought behind the database table structure make the queries easy to construct. Once you download the NaviKnow database, we encourage you to take a look at the SQL statements making up each query to observe and understand how they are put together so you can customize if necessary.
Acting on the Plan
Having a plan is good, but what do you do with it? Below is a short demonstration showing the steps to link the data in your dispersion model project database to your AQA report. Put your report together using the direct links to the database. You get that call that the input data need to change. Make the changes in your database. Re-run the model. Process your model results. Import and insert the data into your database. Then refresh the data link in your report to ensure all changes are included in the report.
Summary
To make sure you can quickly respond to any changes in you dispersion model input or output data, take advantage of all the available tools you can, such as the free NaviKnow Access dispersion model database. Populate the database tables with your project specific data. To put your tools into action, link the database queries and tables to you AQA report.
The next time you have a series of updates to make in your AQA report, just place your cursor on the affected tables in your report, click the data update button (of F9), and you are done. No more worries.
If you found this article informative, there is more helpful and actionable information for you. Go to http://learn.naviknow.com to see a list of past webinar mini-courses. Every Wednesday (Webinar Wednesday), NaviKnow is offering FREE webinar mini-courses on topics related to air quality dispersion modeling and air quality permitting. If you want to be on our email list, drop me a line at [email protected].
One of the goals of NaviKnow is to create an air quality professional community to share ideas and helpful hints like those covered in this article. So if you found this article helpful, please share with a colleague.
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