Differential Equation Plotter

The DiffEQPlotter explores graphical solutions to differential equation systems. Nine equation system families are provided - some simple algebraic systems, some ecology models, and some limit cycles. Each can be tuned by setting constants. Paired time plot and phase plot show the behavior of the system (trajectory) from any selected starting point. The phase plot also shows the "nullclines" (where the derivative of each equation is zero), and a vector field showing the tendency of the system across a grid over the plane.

Though not "fractals" software, it was developed for the same mathematics professor, Michael Frame of Yale University.

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Pattern Blocks 4

Pattern Blocks are used in early math and just for fun. Great for drawing mandalas, tilings, and tesselations. Originally written as a toy for my daughter in 1998, this is my most popular app by a landslide. Latest version features full-browser resizing, better email, hundreds of backgrounds, and keystroke shortcuts. Now with Art Gallery for kid-safe sharing!

 

Mandalar is PatternBlocks for mobile! PatternBlocks is now released as a mobile app. See Mandalar. Still in Adobe Flex - all web/mobile platforms are cross-operable.

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SimWatershed

SimWatershed is loosely based on the real-life Esopus Creek watershed, part of the naturally-cleaned water supply of New York City. SimWatershed implements two online labs, for the Yale School of Forestry graduate course Science to Solutions: How Should We Manage Water.

In the "Biophysics" lab, students explore how water quality is affected by adjusting land use - suburban, agricultural, livestock, and forest. Then in the "Solutions" lab, buying land costs money and faces limits. Other social treatments are available at a price: best management practices, upgrading the local sewage treatment plant, raising prices, or building a city water treatment plant. Scenarios explore present and future, nitrogen and sediment.

Download the "Solutions" lab instructions.

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MapNavigator

MapNavigator interactively explored a 3-year world cruise itinerary. Embedded in a Drupal site, and then reimplemented in HTML5. Drupal and HTML5 is the technology stack I originally recommended, but the client tried to save money and ended up implementing it twice and spending more. That happens.

The client doesn't seem to use an interactive anymore.

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DaisyBall Flex

The Flex incarnation of DaisyBall opted for a general audience presentation - less focus on the mathematics, more on the concepts - with prettier graphics. Choice of DaisyWorld or DaisyBall logic (2D or 3D world). Easy access controls for high level concepts, but you can still set advanced parameters. Much easier to set albedos and number of daisy colors.

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Long Island Sound Barcode Kiosk

Built the software for a barcode-driven Long Island Sound kiosk at the Peabody Museum of Natural History. This kiosk has a collection of barcoded items from Long Island Sound, and a barcode scannner, to make the kiosk display information on that item. Visitors can also get their own barcode, and scan themselves in, and leave a webcam video message. None of this is online, unfortunately, due to concerns from Yale Legal.

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CrossPlan / Cross-Suite

CrossPlan / Cross-Suite was a site for social integrated circuit block-level layout editing. I built database, intelligent integrated circuit editor, design history management, integrated instant messaging, and the whole Drupal site, for The Shearwater Group and Pinebush Technologies. The recession put the project on terminal hold.

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FlexSimpleStats


FlexSimpleStats
tracks semantic usage statistics within my simulators - what users actually do with them. These days, one can use Google Analytics for this, but SimpleStats predates GA by years. The server side of SimpleStats is implemented in PHP and MySQL, called by client-side Java, Flash, or Flex. This tool browses and charts CourseWare historical usage data, back to January, 2004. Originally implemented in Flash, now in Flex.

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