英和和英

形容詞

unistable (not comparable)

1. (mathematics, of a polyhedron) stable when resting on one of its faces
   • 1970, Research Paper, page 22:

     24. Are there unistable polyhedra with less than 19 faces? / A unistable polyhedron is one which when made of material of uniform density, will rest in stable equilibrium on only one of its faces.

   • 1979, IEEE Computer Society, Exploding Technology, Responsible Growth: Digest of Papers, pages 158, 159:

     There are two basic types of amorphous materials—the unistable and the bistable. The unistable material is one in which there are no structural changes. […] The mechanisms for carrier control in the unistable materials are electronic.

   • 1990, Klamkin, Murray S., Problems in Applied Mathematics: Selections from SIAM Review, Society for Industrial and Applied Mathematics, →ISBN, page 478:

     (b) What is the least dimension, if any, in which a simplex can be unistable? If the condition of uniform density of material is relaxed, then a simplex can be unistable in 3 dimensions.