Mathematics Interdisciplinary Research
Volume:7 Issue: 1, Winter 2022

The study of hypercompositional structures (introduced by Marty) is now considered of a great value because of its applications in various sciences. In this paper, we focus on a special hypercompositional structure; quasi-ordering hypergroup. In this regard, we discuss some of the quasi-ordering hypergroup’s properties and investigate some relations on it. Then, we present an application of quasi-ordering hypercompositional structures in genetics and define ordered hypercompositional structures for both sets: phenotypes and genotypes of F2-offspring.

Common oil and gas fields are among the most valuable income and national wealth sources, so production delays cause irreparable damage to the national economy. The existing functions of revenues and production costs of gas fields have been identified and extracted from the current literature to optimize the production strategy. Cost func-tions include exploration, development, operation, production facility and wellhead, facility depreciation costs, and revenue functions include demand and income functions. After designing the model using mathematical optimiza-tion, the decision variables’ values have been calculated as optimal production, selling price, and profit for each play-er. For this purpose, two strategies of cooperation and non-cooperation were considered for each player. Solving the designed games showed that the best strategy and Nash equilibrium for the research case study is the strategy of co-operation. Also, according to the results of the equilibrium of designed games based on cooperation strategy, it is suggested that one of the main approaches of research case study in common fields is the process of multilateral and cooperative development.

Using a filter technique, a new efficient nonmonotone trust region method is proposed. The proposed scheme is based on updating the approximation of the Hessian matrix with the scaled memoryless BFGS update formula. To update the trust region radius, an appropriate adaptive scheme is used. Moreover, a proper nonmonotone procedure is applied. Assuming some suitable assumptions, the global convergence is obtained. Numerical results are reported to show the efficiency of the offered approach.

In this paper, we consider hyperbolic Ricci-Bourguignon flow on a compact Riemannian manifold M coupled with the harmonic map flow between M and a fixed manifold N. At the first, we prove the unique short-time existence to solution of this system. Then, we find the second variational of some geometric structure of M along this system such as, curvature tensors. In addition, for emphasize the importance of hyperbolic Ricci-Bourguignon flow, we give some examples of this flow on Riemannian manifolds.

Differential pencils on the half-line with a spectral boundary condition having a discontinuity in an interior point are investigated. We prove two uniqueness theorems: (i) knowing β1 ,β0 and potentials p,q on (0,a), only eigenvalues suffice to determine the boundary value problem B. (ii) some in formation on eigenfunctions at x = a and eigenvalues establish the boundary value problem B.

Many graphs are constructed from simpler ones by the use of operations on graphs, and as a consequence, the properties of the resulting constructions are strongly related to the properties of their constituents. This paper is concerned with computing some distance-based graph invariants for three constructions on graphs namely double graph, extended double cover, and strong double graph.