Here is a partial list of projects I've completed. More write-ups are underway.


Xbox 360 Emulator

Microsoft’s Xbox 360 console used completely different hardware (PowerPC CPU, ATI GPU, etc.) than the original Xbox console (x86 CPU, NVidia GPU, etc.). To enable customers to play original Xbox games on the new console, we created an emulator. One Distinguished Engineer called this “the hardest technical problem Microsoft has ever solved.”


Microsoft SQLXML

SQLXML added XML technologies to Microsoft’s SQL Server 2000, making it possible to store XML data as relational data and vice-versa. Among other things, I implemented the XPath over SQL Server.


Radiative Transfer

Radiative transfer is the process by which radiation propagates through space. Radiation is absorbed and emitted by interstellar media. At NASA, I implemented a radiative transfer Monte Carlo simulation – effectively a a volumetric backwards ray tracer. We used this to predict results from Hubble Space Telescope observations.


Extrasolar Planets

Extrasolar planets are planets outside our solar system. At the time, no one had imaged one optically, although several had been detected indirectly through astrometry and other means. Dr. Dave Van Buren and I spent a few nights at Palomar Observatory using an experimental new infrared detector to look for planets outside our solar system in the hopes of capturing one in an image.


Even Cycles

My Master’s Thesis was on the computational complexity of finding even cycles in directed graphs. At the time this was an unsolved problem. There are now polynomial-time algorithms for finding even cycles in directed and undirected graphs.



AstroVR was an online virtual environment for astronomy research. Before the World Wide Web existed, we built networked audio/video-conferencing, multi-user whiteboards, and many other online collaborative tools.


Personal Website

I created my first website in 1993, using an FTP server and the beta NCSA Mosaic browser. My current site uses Jekyll, git, and DreamHost.



The marimba is a musical instrument similar to the xylophone. I’ve been playing it off-and-on since high school.


Graceful Graphs

Conjectures about graceful graphs are simple to state but fiendishly hard to prove. I found several infinite families of graceful graphs.