Volume 26, No. 1 (2016)
Articles
FIXED POINT THEOREMS IN ORDERED CONE B-METRIC SPACES
AKBAR ZADA(1), RAHIM SHAH(2) AND TONGXING LI(3)
In the current work, some fixed point theorems are proved on ordered cone b-metric space motivated by [2], [14] and [15]. The proposed theorems extend and unify several well-known comparable results in the literature to ordered cone b-metric spaces. Some supporting examples are given.
GENERALIZATIONS OF TRIANGULATED GRAPHS
MIHAI TALMACIU
Using weak decomposition, we characterize in a unified manner the classes of doubly chordal, of hereditary dually chordal and of strongly chordal graphs. We also give a recognition algorithm that is applicable for doubly chordal graphs, for hereditary dually chordal and for strongly chordal graphs. In addition, we determine the combinatorial op-timization numbers in efficient time for all the above classes of graphs.
FAST ALGORITHMS OF HEREDITARY DOUBLY CHORDAL GRAPHS
MIHAI TALMACIU
We give a characterization of hereditary doubly chordal graphs using weak decomposi-tion. We also give a recognition algorithm for hereditary doubly chordal graphs and we determine the combinatorial optimization numbers in efficient time.
PROPERTIES OF α-GENERALIZED REGULAR WEAKLY CONTINUOUS FUNCTIONS AND PASTING LEMMA
N. SELVANAYAKI(1) AND GNANAMBAL ILANGO(2)
In this paper, some properties of αgrw –continuous functions are discussed and the notion of αgrw -closed graph is introduced. Also, the pasting lemma for αgrw -continuous func-tions is proved.
A GENERAL FIXED POINT THEOREM FOR SELF MAPPINGS IN GP - METRIC SPACES
VALERIU POPA(1) AND ALINA-MIHAELA PATRICIU(2)
The purpose of this paper is to prove a general fixed point theorem in GP - metric spaces for mappings satisfying an implicit relation, which generalizes and improves Theorem 2.10 [6]. In the last part of the paper we prove that these mappings satisfy property (P) in GP - metric spaces and if GP - metric is symmetric, then the fixed point problems is well posed.
A GENERAL FIXED POINT THEOREM IN COMPLETE G - METRIC SPACES FOR WEAKLY COMPATIBLE PAIRS SATISFYING A Ф- IMPLICIT RELATION
ALINA-MIHAELA PATRICIU(1) AND VALERIU POPA(2)
In this paper a general fixed point theorem in complete G - metric spaces for weakly com-patible pairs satisfying a Ф - implicit relation is proved, which generalizes and unifies the results given by Theorems 3.2 and 3.3 [20].
SOME GEOMETRICAL PROPERTIES OF PFAFF SYSTEMS ON MANIFOLDS
VALER NIMINEŢ
We continue our investigation [7] of Pfaff systems on manifolds by studying some geo-metrical properties and some consequences of these structures. We point out new geomet-rical invariants of a distributions on manifolds.
FINSLERIAN MECHANICAL SYSTEMS IN CONFORMAL FINSLER SPACES
OTILIA LUNGU
In [2] Hashiguchi studied the conformal change of a Finsler metric, namely \overline{F} (x; y) = e^c(x)F (x; y). Since that moment other authors studied different kind of changes. In this paper we investigate the effect of the conformal change on Fins-lerian mechanical systems. We established the difference between the coefficients of the cannonical d-connection .
R_cl-LOCALLY CONNECTED SPACES
J. K. KOHLI(1), D. SINGH(2) AND B. K. TYAGI(3)
A new generalization of local connectedness called ‘R_cl-local connectedness’ is intro-duced. Basic properties of R_cl-locally connected spaces are studied and their place in the hierarchy of variants of local connectedness which already exist in the literature is discussed. R_cl-local connectedness is preserved in the passage to r_cl-open sets and is invariant under disjoint topological sums. A necessary and sufficient condition for a product of R_cl-local connected spaces be R_cl-locally connected proved. Preservation of R_cl-local connectedness under mappings is investigated. It is shown that R_cl-local con-nectedness is preserved under quotients and an r_cl-quotient of an R_cl-locally connected space is locally connected. The category of R_cl-locally connected spaces is properly con-tained in the category of sum connected spaces (Math. Nachrichten 82(1978), 121-129; Ann. Acad. Sci. Fenn. AI Math. 3 (1977), 185-205) and constitutes a mono-coreflective subcategory of TOP.
A CLASS OF COMPLETE METRIZABLE Q-ALGEBRAS
E. ANSARI-PIRI(1), M. SABET(2) AND S. SHARIFI(3)
The fundamental topological algebras, which extend both locally convex and locally bounded concepts, have been introduced before. Here we introduce a class of fundamen-tal Q-algebras.
LOCAL FUNCTION Γ * IN IDEAL TOPOLOGICAL SPACES
AHMAD AL-OMARI(1) AND TAKASHI NOIRI(2)
Let (X, τ, I) be an ideal topological space. For a subset A of X, a local function Γ*(A)(I, τ ) is defined as follows: Γ *(A)(I, τ ) = {x in X : A ∩ U not in I, for every regular open set U containing x}. This coincides with the δ-local functions due to Hatir et al. [2]. By using Γ* (A)(I, τ ), an operator Ψ_Γ* : P(X) → τ ^δ is defined as the dual of the δ-local func-tion and its relations with δ-codense ideals are investigated.