Bulletin of Computational Applied Mathematics

12

Authors: Nima Ghanbari, Saeid Alikhani

Let G be a simple graph. A total dominator coloring of G is a proper coloring of the vertices of G in which each vertex of the graph is adjacent to every vertex of some color class. The total dominator chromatic number Xtd(G)of G is the minimum number of colors among all total dominator coloring of G. In this paper, we examine the effects on Xtd(G) when G is modified by operations on vertex and edge of G.

20

Authors: Anna Formica

"Formal Concept Analysis" and "Rough Set Theory" provide two mathematical frameworks in information management which have been developed almost independently in the past. Currently, their integration is revealing very interesting in different research fields, such as knowledge discovery, data mining, information retrieval, elearning, and ontology engineering. In this paper, we show how "Rough Set Theory" can be employed in combination with a generalization of "Formal Concept Analysis" for modeling uncertainty information ("Fuzzy Formal Concept Analysis") to perform Semantic Web search. In particular this paper presents an updated evaluation of a previous proposal of the author which has been addressed because of the increasing interest in this topic and, at the same time, the absence in the literature of significant proposals combining these two frameworks.

25

Authors: Naveed Yaqoob, Muhammad Akram

In this research article, we introduce the notion of complex neutrosophic graphs (cn-graphs, for short) and discuss some basic operations related to cn-graphs. We describe these operations with some examples. We also present energy of complex neutrosophic graphs.

18

Authors: Cemil Tunç, Osman Tunç

The authors of this article deal with a first order non-linear Volterra integro-differential equation (NVIDE). To this end, the conditions are obtained which are sufficient for stability (S), boundedness (B), and for every solution x of (NVIDE) is integrable. For properties of solutions of (NVIDE) considered three new theorems on (S), (B) and integrability properties of solutions are proved. The methods of the proofs involve constructing of a suitable Lyapunov functional (LF) which gives meaningful results for the problems to be investigated. The conditions to be given involve nonlinear improvement and extensions of those conditions found in the literature. An example is provided to illustrate the effectiveness of the proposed results. The results obtained are new and complements that found in the literature.

24

Authors: Sujit Kumar Sardar, Sugato Gupta, Bijan Davvaz

The soft category theory offers a way to study soft theories developed so far more generally. The main purpose of this paper is to introduce the basic algebraic operations in soft categories, and for that we introduce some algebraic operations, like intersection and union, in categories. Also, the notion of composition of soft functors is introduced to form category of all soft categories.

33

Authors: Emrah Altun, Haitham M. Yousof, Gholamhoss G. Hamedani

In this paper, we introduced a new flexible extension of the Generalized Half-Normal lifetime model as well as a new log-location regression model based on the proposed model. Some useful characterization results are presented and some mathematical properties are derived. The maximum likelihood method is used to estimate the model parameters by means of a graphical Monte Carlo simulation study. We show that the new log-location regression lifetime model can be very useful in analysing real data and provide more realistic fits than other regression models. Index plot of the modified deviance residual and Q-Q plot for modified deviance residual are presented to illustrate that our new model is more appropriate to HIV data set than other competitive models like log-odd log-logistic generalized half-normal regression model and log-generalized half-normal regression model. The sensitivity analysis is used via the index plot of generalized cook distance to discover the possible influential observations.