We investigate a relation about subadditivity of functions. Based on subadditivity of functions, we consider some conditions for continuous t-norms to act as the weakest t-norm TW-based addition. This work extends some results of Marková-Stupňanová [15], Mesiar [18].
In this paper, we give the mapping theorems on $\aleph $-spaces and $g$-metrizable spaces by means of some sequence-covering mappings, mssc-mappings and $\pi $-mappings.
In this paper, the relationships between metric spaces and $g$-metrizable spaces are established in terms of certain quotient mappings, which is an answer to Alexandroff’s problems.
In this note we study finite $p$-groups $G=AB$ admitting a factorization by an Abelian subgroup $A$ and a subgroup $B$. As a consequence of our results we prove that if $B$ contains an Abelian subgroup of index $p^{n-1}$ then $G$ has derived length at most $2n$.
In this note we give an answer to a problem of Gheorghiță Zbăganu that arose from the study of the properties of the moments of the iterates of the integrated tail operator.
We describe a class of bivariate copulas having a fixed diagonal section. The obtained class contains both the Fréchet upper and lower bounds and it allows to describe non-trivial tail dependence coefficients along both the diagonals of the unit square.
This paper studies the relationship between the sections and the Chern or Pontrjagin classes of a vector bundle by the theory of connection. Our results are natural generalizations of the Gauss-Bonnet Theorem.
Let L be an MS-algebra with congruence permutable skeleton. We prove that solving a system of congruences (θ1, . . . , θn; x1, . . . , xn) in L can be reduced to solving the restriction of the system to the skeleton of L, plus solving the restrictions of the system to the intervals [x1, x¯¯1], . . . , [xn, x¯¯n].
The minimum orders of degree-continuous graphs with prescribed degree sets were investigated by Gimbel and Zhang, Czechoslovak Math. J. 51 (126) (2001), 163–171. The minimum orders were not completely determined in some cases. In this note, the exact values of the minimum orders for these cases are obtained by giving improved upper bounds.