let (m,g ) be a compact immersed hypersurface of (rn+1,) , λ1 the first nonzeroeigenvalue, α the mean curvature, ρ the support function, a the shape operator, vol (m ) the volume of m,and s the scalar curvature of m. in this paper, we established some eigenvalue inequalities and proved theabove.1) 1 2 2 2 2m ma dv dvn∫ ρ ≥ ∫ α ρ ,2)( )2 2 1 2m 1 mdv s dvn nα ρ ≥ ρ∫ − ∫ ,3) if the scalar curvatu...

Recently, we have used the symmetric bracket of vector fields, and developed the notion of the symmetric derivation. Using this machinery, we have defined the concept of symmetric curvature. This concept is natural and is related to the notions divergence and Laplacian of vector fields. This concept is also related to the derivations on the algebra of symmetric forms which has been discu...

In 1961, A. Wagner proposed the problem of determining all the subgroups of PΓL(n> q) which are 2-transitive on the points of the projective space PGin — l,q), where n ^ 3. The only known groups with this property are: those containing PSL^n, q), and subgroups of PSL(4, 2) isomorphic to A7. It seems unlikely that there are others, Wagner proved that this is the case when n ^ 5. In unpublished w...

abstract limitations of traditional (conventional) soil surveys and improvement of information technology have lead soil surveyors to invent new methods which are generally called digital soil mapping (dsm). the aim of these methods is the prediction of soil classes or soil properties based on easily-available or measuring environmental variables. the objective of this investigation is to study...

The groups in the title are classified, provided they are not too highly transitive. Let G be a primitive permutation group on a finite set S of n points. In 1871, Jordan initiated the study of G under the additional assumption that there is a transitive subgroup H of degree m, where 1 < m < n; that is, H fixes n m points and is transitive on the remaining points. THEOREM 1. I f m is a prime po...