Seismic analysis and models the actual physics, much like common video games often have "physics engines". Very large and complex buildings can be modeled in this way (such as the Osaka International Convention Center). Structural analysis methods can be divided into the following five categories. This approach defines a series of forces acting on a building to represent the effect of earthquake ground motion, typically defined by a seismic design response spectrum. It assumes that the building responds in its fundamental mode. For this to be true, the building must be low-rise and must not twist significantly when the ground moves. The
Seismic Experiment for Interior Structure has large marsquakes, they may allow the deep interior to be determined. As the vibrations pass through the planet they are affected by the properties of the materials and its configuration. For example, the effect of tidal forces on Mars by Phobos, which should be about 10 mm, would be noticeably affected by a liquid Mars core. Even without any marsquake, it should be possible after about six months of observation to use this method to increase or decrease the likelihood Mars has a liquid core. Seismic Experiment for Interior Structure The Seismic Experiment for Interior Structure (SEIS) is a