My 2D Hydrodynamic GPU code is over an order of magnitude faster than CPU codes (its source is available on GitHub). It is wasteful if I do not apply it to study some (astro-) physical problems. It turns out that, by introducing a simple -term, the […]
While there are many great existing tutorial online (e.g., from the Pro Git book, official git website, GitHub, Bitbucket, to Roger Dudler), my slides touch features that are mot useful for scientists working in a group. Please feel […]
I put up a new paper “GRay: a Massively Parallel GPU-Based Code for Ray Tracing in Relativistic Spacetimes” on arXiv. Here is the abstract:
We introduce GRay, a massively parallel integrator designed to trace the trajectories of billions of photons in a curved spacetime. This GPU-based integrator employs the stream processing paradigm, is implemented […]
One of my primary schoolmates posted a Bloomberg interview question on Facebook. I found it pretty interesting so let me restate it here:
2 eggs will break if you drop them above a particular height H. You are asked to find out H to its closet integer multiple of 1ft. It is known that 1ft <= […]
I just put up a new paper “Dynamics of Saturated Energy Condensation in Two-Dimensional Turbulence” on arXiv. Here is the abstract:
We derive and numerically confirm that the saturation of energy condensation in two-dimensional turbulence is governed by the balance between forcing and small-scale dissipation. The time scale of saturation is inversely proportional to […]
The Portable Batch System (PBS) and Load Sharing Facility (LSF) are popular job-schedulers for batch environments. Their goal is to manage computing jobs among the available computing resources. The figure on the right shows the current load of the Odyssey cluster at Harvard Research Computing. It demonstrates how computer jobs submitted […]
When working with LaTeX, it is recommended to start each sentence on a new line. The reasons can be found in Axel Brandenburg’s computing tips and this stack overflow page so I won’t repeat them here. However, as an emacs user, I always want emacs do the formatting for me.
The existing solutions […]
I am recently interested in the properties of Bose-Einstein condensation in two-dimension hydrodynamic turbulence. Without the Ekman term (linear friction), the time to reach a saturated state is proportional to the Reynolds number, which can be very long. Therefore, I want to improve my GPU code to use adaptive time stepping.