We uploaded an open-source version of SimzLab to our github project at https://github.com/RichardHerz.
SimzLab was an extension of the concept of ReactorLab to enable different types of labs, or “courses,” to be distributed from a single platform. Originally, one of the courses in SimzLab was ReactorLab. We later took ReactorLab out of SimzLab and stopped development on SimzLab due to lack of development resources.
The current SimzLab includes PureWaterLab, a project about water purification, a process Control Lab, and a Heat Exchanger simulation.
The Download section of this web site has a standalone version of SimzLab for Windows OS. For other platforms, you can download and use the open-source version with the free LiveCode Community Edition development tool.
At our GitHub pages, we added examples of the individual controls – checkboxes, radio buttons, plots, etc. – that we use in our Web Lab simulations. These examples are easier to read and understand than controls embedded in a complete simulation.
See these examples at our GitHub site
In addition, all of our Web Lab source code can be viewed in your web browser by viewing the page source.
We have been working on our web page design project, lcCardLayoutToWeb, which is posted at GitHub. Here is a screenshot of a test page.
This new work should allow us to make interactive web apps more easily.
See our newest Web Lab, “Dynamic diffusion and reaction in a porous solid catalyst” at the Web Labs tab above. See the latest version of this web lab in our open-source projects at GitHub, https://github.com/RichardHerz/.
Space-time plots are a beautiful way to view dynamic reaction-diffusion systems. We added one to the Web Lab, “Dynamic diffusion and reaction in a porous solid catalyst.” Here is a static screen shot from the lab.
We prepared static plots of space-time data for our previous research work, e.g., at http://escholarship.org/uc/item/9bc7v3kv. We were inspired to make them dynamically by the fluid dynamics simulations of Oliver Hunt at https://nerget.com/fluidSim/ and Daniel Schroeder at http://physics.weber.edu/schroeder/fluids/. Those pages showed us that this was possible to do in a web page.
We recently released the desktop Reactor Lab software as an open-source project on GitHub. View our open-source projects at https://github.com/RichardHerz. Contact us if you are interested in using this version or learning more about the structure and the code. The Lab is constructed with the open-source, Community Edition of LiveCode, which can be obtained at https://livecode.org.
We posted a new web lab with a simulation of dynamic diffusion and reaction in a porous, solid catalyst layer.
This our first web lab with multiple plots: two strip charts showing time history, and two profile charts showing time-varying concentration profiles in the catalyst layer. The way we handle data for these plots is different than we do in Lab 1, which has one strip chart plot. Our code structure continues to be under development.
In an earlier post, we mentioned the web apps being developed by Tony Butterfield. His web apps have a different structure than ours, and it is interesting to compare these two approaches. You can view the source code of the web apps by choosing View Source in your web browser.
Butterfield’s web apps have a single method that updates the state of the simulation at each time step, vs. our process unit objects, each of which contain a method to update themselves at each time step. For plotting, his web apps record variables values at each time step in each variable object, vs. our 3D numeric array that records the history of all variable values, with individual process objects storing only their current values.
Both approaches work, and it is valuable to have a choice for web app development.
I was interested to learn about the work of Margaret Hamilton, who was awarded the Presidential Medal of Freedom yesterday. As a young woman, she led a team that designed the flight control software for the Apollo moon landers. This period was during the early days of computer programming when software design practices were just starting to be invented. Hamilton developed a theory and methodology for “design before the fact” of fault-free and fault-tolerant, real-time software control systems. The class of systems considered are asynchronous, discrete-event systems. This includes chemical batch process scheduling and control. Our web apps simulate continuous processes. Design Before the Fact contrasts with the development strategy we use, as outlined in my last post, but we will learn from Hamilton’s work.
Also at the ceremony at the White House yesterday, Grace Hopper was posthumously awarded the Presidential Medal of Freedom. She was an early pioneer in computing, invented the first software compiler, and popularized the idea of machine-independent programming languages.
The goal of our Web Labs is a toolbox that enables development of interactive web simulations or “labs,” and a set of labs built with this toolbox. Our development practice is as follows.
First, Get something up on the screen. Often this involves finding an example on the web and modifying it. Don’t spend a lot of time designing and thinking before something simple gets running. We believe that it is better to get something useful running than it is to have a beautiful plan and theory in development but nothing working to show for your time.
Second, repeat the following:
- Add functionality.
- As we observe repetition of code and see patterns developing, generalize the code. Have the objective of maximizing code in libraries and minimizing code needed to build new labs.
- As we observe patterns developing in the user interfaces, refine the design of a user interface guideline that is simple and consistent between labs in order to speed development of new labs and speed user comprehension when entering new labs.
Reactor Lab is a pioneer in developing interactive simulations for active learning. This is a screenshot of an experiment in the Lab in March 1993, when the Lab was a single HyperCard stack. The screenshot was taken after it was converted to a LiveCode stack to keep it alive and operable on today’s computers. Click on the image to see a larger version.
Here is the same experiment in today’s Reactor Lab.
A brief history of the development of Reactor Lab through 2006 is available at LiveCode Journal. The article refers to Revolution, which was LiveCode’s previous name.