Chemical compounds, characteristics, and molecular structures are inevitably connected. Topological indices are numerical values connected with chemical molecular graphs that contribute to understanding a chemical compounds physical qualities, chemical reactivity, and biological activity. In this study, we have obtained some topological properties of the first dominating David derived (DDD) networks and computed several K-Banhatti polynomials of the first type of DDD.

The main purpose from this paper is to introduce a new kind of soft open sets in soft
topological spaces called soft omega open sets and we show that the collection of
every soft omega open sets in a soft topological space (X,~,E) forms a soft topology
  ~
on X which is soft finer than  ~
. Moreover we use soft omega open sets to define
and study new classes of soft functions called weakly soft omega open functions and
weakly soft omega closed functions which are weaker than weakly soft open functions
and weakly soft closed functions respectively. We obtain their basic properties, their
characterizations, and their relationships with other kinds of soft functions between
soft topological spaces.<

This paper aims to study the role of a prey refuge that depends on both prey and predator species on the dynamics of a food web model. It is assumed that the food transfer among the web levels occurs according to Lotka-Volterra functional response. The solution properties, such as existence, uniqueness, and uniform boundedness, are discussed. The local, as well as the global, stabilities of the solution of the system are investigated. The persistence of the system is studied with the assistance of average Lyapunov function. The local bifurcation conditions that may occur near the equilibrium points are established. Finally, numerical simulation is used to confirm our obtained results. It is observed that the system has only one type of a

The dynamics of a single condensing two-phase bubble of two different dispersed-continuous systems were studied. The systems were, CCl₄ - water and CCl₄ - 100% glycerol. Cinephotography was used to determine the change in height, diameter and time. These results were used to determine the experimental rise velocity of the bubble, which was compared with a theoretical one based on some equations used. It was found that the velocity of the first system remained almost constant, while it decreased gradually for the second system.

In this work, the external switching dynamics of a Fabry-Perot etalon are studied via optical bistability system simulation. The simulated set-up of this investigation consists of two laser beams; the first beam is continuous (CW) which is considered as a biasing beam and capable of holding the bistable system for a certain range, which we are interested in, from a point that is very close self-switching to a point where the switching is unachievable. The second beam is modulated by passing the first beam through an acousto-optic modulator (AOM) to produce pulses with a minimum rise time and is used as an external source (coherent switching). In this work, we obtained the optical bistable loops by applying absorption coefficient (α) =

      This paper aims to introduce a concept of an equilibrium point of a dynamical system which will call it almost global asymptotically stable. We also propose and analyze a prey-predator model with a suggested  function growth in prey species. Firstly the existence and local stability of all its equilibria are studied. After that the model is extended to an optimal control problem to obtain an optimal harvesting strategy. The discrete time version of Pontryagin's maximum principle is applied to solve the optimality problem. The characterization of the optimal harvesting variable and the adjoint variables are derived. Finally these theoretical results are demonstrated with numerical simulations.

The aim of this thesis is to introduce a new concept of fibrewise topological spaces which is said to be fibrewise slightly topological spaces. We generalize some of the main results that have been reached from fibrewise topology into fibrewise slightly topological space. We introduce the concepts of fibrewise slightly closed, fibrewise slightly open, fibrewise locally sliceable, and fibrewise locally sectionable slightly topological spaces. Also, state and prove several propositions related to these concepts. On the other hand, extend separation axioms of ordinary topology into fibrewise setting. The separation axioms are said to be fibrewise slightly T_0 spaces, fibrewise slightly T_1 spaces, fibrewise slightly R_0 spaces, fibrewise s

This paper is devoted to the discussion the relationships of connectedness between some types of graphs (resp. digraph) and Gm-closure spaces by using graph closure operators.