The two simplest theories for organized particles are for small rigid ones (4), elongated rod-like or flat, disklike ones, and for soft, deformable spherical particles (3).

• 对颗粒组织的两个最简单的理论是，小的刚性颗粒，细长的棒状颗粒或扁平的盘状颗粒；柔软的可变形的球状颗粒。