The particle-calculation program coupled with the simulation on the supercomputer generates particle data for visualization and outputs it on the storage. The control program aggregates particle data and transfers it to a user’s PC via the internet. The drawing program on the user’s PC displays the visualization of the particle data on the viewer screen. The user observes the visualized image and adjusts visualization parameters such as color and opacity. The adjusted visualization parameters are output to the storage via the control program. The particle-calculation program reads visualization parameters from the storage and uses it for particle generation.