الأبحاث والمقالات
p--Local formations whose length≤ 3.
| | 2000
Throughout this paper, all groups are finite. Recall that a formation
is a homomorphic F of groups such that each group G has a smallest normal
subgroup (denoted by G
F
) whose quotient is still in F. A formation F is said to
be p-local if it contains each group G with G/(Φ(G) ∩ Op(G)) ∈ F. Our main
goal here is to prove the following theorem
Finite Groups with X-permutable Maximal Subgroups of Sylow Subgroups.
| | 2000
Let A,B be subgroups of a group G and ∅≠X⊆G. Then A is said to be X-permutable with B if there exists an element x∈X such that AB x =B x A. In this paper we study finite groups in which maximal subgroups of Sylow subgroups are X-permutable either with maximal subgroups or with Sylow subgroups.
Fuzzy folding of a fuzzy group and its fuzzy retractions
| | 2000
The main target of this paper is to discuss whether the fuzzy folding of a fuzzy
group is a fuzzy group or not. In addition, the relation between the fuzzy folding
and the fuzzy retractions are obtained.AMS Mathematics Subject Classiftcation
Noetherian and Artinian Ternary Ring
| | 2000
The main aim of this article is to study some special elements (zero divisors and units) in ternary rings. Then, the
main properties and concepts of noetherian and artinian ternary
rings have been studied. In addition, new results on noetherian and artinian ternary rings have been investigated.
On c-Normal Subgroups of Finite Groups
| | 2000
Let G be a finite group. We fix in every noncyclic Sylow subgroup P of G some subgroup D satisfying 1 < |D| < |P| and study the structure of G under the assumption that all subgroups H of P with |H| = |D| are c-normal in G.
On formula-Normal Subgroups of Finite Groups
| | 2000
Let G be a finite group. We say that a subgroup H of G is -normal in G if G has a subnormal subgroup T such that TH = G and (H ∩ T)HG/HG is contained in the -hypercenter of G/HG, where is the class of the finite supersoluble groups. We study the structure of G under the assumption that some subgroups of G are -normal in G.
On Some Finite Arithmetic Groups and Generalized
Permutation Modules
| | 2000
We investigate integral Galois stable representations of finite groups over local and global fields and their integers under the
ground field extensions related to permutation modules. We consider normal extensions E/F and subgroups G ⊂ GLn(E) stable under
the natural operation of the Galois group of E/F with some extra integrality conditions. The possible realization fields of G with these
integrality conditions are of special interest, and we consider certain criteria of integrality for representations in GLn(E). We also study
a series of related arithmetic problems and examples.
On S-quasinormal subgroups and some applications
| | 2000
A subgroup H of a group G is called S-quasinormal in G if it permutes with every Sylow subgroup of G.The structure of the group G has been studied earlier by many authors under the assumption that the maximal or the minimal subgroups of the Sylow subgroups are well situated in G. In the present paper we are cincerned with the study of the structure of a finite group under the assumption that some subgroups of G are S-quasinormal in G, and we discuss some methods and applications.
On S-quasinormal subgroups of finite group
| | 2000
A subgroup H of a group G is called S− quasinormal in G if it permutes with every Sylow subgroup of G. In this paper, we extend the study on the structure of a finite group under the assumption that some subgroups of F∗(G) are S− quasinormal in G.
On Supersolubility of Some Finite Factorizable Groups
| | 2000
It is proved that a finite group G=AB is supersoluble provided that A and B are such supersolube subgroups of G that every cyclic subgroup of A permutes with every Sylow subgroup of B and if in return every cyclic subgroup of B permutes with every Sylow subgroup of A.
Semi-derivations acting on Jordan ideals of rings with involution
| | 2000
Our aim in this paper is to prove some properties of semi-derivations centralizing on Jordan ideals of rings with involution. Some well known results characterizing commutativity of prime rings by derivations have been generalized by using semi-derivations. Moreover, we provide examples to show that our hypotheses are not superfluous.
Some commutativity criteria for prime rings with differential identities on Jordan ideals
| | 2000
In this article, we present some commutativity theorems for a ring R equipped with a generalized derivation satisfying certain differential identities on Jordan ideals of R. Some related results for prime rings are also discussed. Finally; we provide examples to show that the assumed restrictions are not superfluous.
Some conditions for p-solubility of finite group
| | 2000
A subgroup H of a group G is c-subnormal in G if G has a subnormal subgroup T such that
HT=G and T 3 H ⊆ HG.
[1] Using this concept, in Jaraden obtain
[1]
some new conditions for solubility of a
finite group are given. Here we obtain local versions of these results.
p--Local formations whose length≤ 3.
| | 2000
Throughout this paper, all groups are finite. Recall that a formation
is a homomorphic F of groups such that each group G has a smallest normal
subgroup (denoted by G
F
) whose quotient is still in F. A formation F is said to
be p-local if it contains each group G with G/(Φ(G) ∩ Op(G)) ∈ F. Our main
goal here is to prove the following theorem
Finite Groups with X-permutable Maximal Subgroups of Sylow Subgroups.
| | 2000
Let A,B be subgroups of a group G and ∅≠X⊆G. Then A is said to be X-permutable with B if there exists an element x∈X such that AB x =B x A. In this paper we study finite groups in which maximal subgroups of Sylow subgroups are X-permutable either with maximal subgroups or with Sylow subgroups.
Fuzzy folding of a fuzzy group and its fuzzy retractions
| | 2000
The main target of this paper is to discuss whether the fuzzy folding of a fuzzy
group is a fuzzy group or not. In addition, the relation between the fuzzy folding
and the fuzzy retractions are obtained.AMS Mathematics Subject Classiftcation
Noetherian and Artinian Ternary Ring
| | 2000
The main aim of this article is to study some special elements (zero divisors and units) in ternary rings. Then, the
main properties and concepts of noetherian and artinian ternary
rings have been studied. In addition, new results on noetherian and artinian ternary rings have been investigated.
On c-Normal Subgroups of Finite Groups
| | 2000
Let G be a finite group. We fix in every noncyclic Sylow subgroup P of G some subgroup D satisfying 1 < |D| < |P| and study the structure of G under the assumption that all subgroups H of P with |H| = |D| are c-normal in G.
On formula-Normal Subgroups of Finite Groups
| | 2000
Let G be a finite group. We say that a subgroup H of G is -normal in G if G has a subnormal subgroup T such that TH = G and (H ∩ T)HG/HG is contained in the -hypercenter of G/HG, where is the class of the finite supersoluble groups. We study the structure of G under the assumption that some subgroups of G are -normal in G.
On Some Finite Arithmetic Groups and Generalized
Permutation Modules
| | 2000
We investigate integral Galois stable representations of finite groups over local and global fields and their integers under the
ground field extensions related to permutation modules. We consider normal extensions E/F and subgroups G ⊂ GLn(E) stable under
the natural operation of the Galois group of E/F with some extra integrality conditions. The possible realization fields of G with these
integrality conditions are of special interest, and we consider certain criteria of integrality for representations in GLn(E). We also study
a series of related arithmetic problems and examples.
On S-quasinormal subgroups and some applications
| | 2000
A subgroup H of a group G is called S-quasinormal in G if it permutes with every Sylow subgroup of G.The structure of the group G has been studied earlier by many authors under the assumption that the maximal or the minimal subgroups of the Sylow subgroups are well situated in G. In the present paper we are cincerned with the study of the structure of a finite group under the assumption that some subgroups of G are S-quasinormal in G, and we discuss some methods and applications.
On S-quasinormal subgroups of finite group
| | 2000
A subgroup H of a group G is called S− quasinormal in G if it permutes with every Sylow subgroup of G. In this paper, we extend the study on the structure of a finite group under the assumption that some subgroups of F∗(G) are S− quasinormal in G.
On Supersolubility of Some Finite Factorizable Groups
| | 2000
It is proved that a finite group G=AB is supersoluble provided that A and B are such supersolube subgroups of G that every cyclic subgroup of A permutes with every Sylow subgroup of B and if in return every cyclic subgroup of B permutes with every Sylow subgroup of A.
Semi-derivations acting on Jordan ideals of rings with involution
| | 2000
Our aim in this paper is to prove some properties of semi-derivations centralizing on Jordan ideals of rings with involution. Some well known results characterizing commutativity of prime rings by derivations have been generalized by using semi-derivations. Moreover, we provide examples to show that our hypotheses are not superfluous.
Some commutativity criteria for prime rings with differential identities on Jordan ideals
| | 2000
In this article, we present some commutativity theorems for a ring R equipped with a generalized derivation satisfying certain differential identities on Jordan ideals of R. Some related results for prime rings are also discussed. Finally; we provide examples to show that the assumed restrictions are not superfluous.
Some conditions for p-solubility of finite group
| | 2000
A subgroup H of a group G is c-subnormal in G if G has a subnormal subgroup T such that
HT=G and T 3 H ⊆ HG.
[1] Using this concept, in Jaraden obtain
[1]
some new conditions for solubility of a
finite group are given. Here we obtain local versions of these results.