Mongolian Mathematical Journal <p>Mongolian Mathematical Journal (MMJ) was originally founded in 1997 by the Mongolian Mathematical Society with the financial support of the National University of Mongolia (1997-2003 named “Journal of Mongolian Mathematical Society”).</p> <p>MMJ is a peer-reviewed journal for the publication of original and survey papers in pure and applied mathematics.</p> <p><strong>Abstracting and indexing in <a title="Google Scholar" href="" target="_blank" rel="noopener">Google Scholar</a>, <a title="Mongolian Mathematical Journal" href="" target="_blank" rel="noopener">Dimensions</a> and <a title="zbMath Open" href="" target="_blank" rel="noopener">zbMath Open</a></strong></p> Mongolian Mathematical Society en-US Mongolian Mathematical Journal 2709-4219 <p>Copyright on any research article in the <strong>Mongolian Mathematical Journal</strong> is retained by the author(s).</p> <p>The authors grant the <strong>Mongolian Mathematical Journal </strong>a license to publish the article and identify itself as the original publisher.</p> <p><br />Articles in the <strong>Mongolian Mathematical Journal</strong> are Open Access articles published under a Creative Commons Attribution NonCommercial (CC-BY-NC)</p> <p>This license permits use, distribution and reproduction in any medium, provided the original work is properly cited, does not allow for commercial use of the original work.</p> Rainbow Options with MS–VAR process <p>This paper presents pricing and hedging methods for rainbow options and lookback options under Markov-Switching Vector Autoregressive (MS–VAR) process. Here we assumed that a regime–switching process is generated by a homogeneous Markov<br>process. An advantage of our model is it depends on economic variables and simple as compared with previous existing papers.</p> Battulga Gankhuu Copyright (c) 2022 Battulga Gankhuu 2023-08-31 2023-08-31 24 1 16 10.5564/mmj.v26i24.3000 Optimal Control Sphere Packing Problem <p>The sphere packing problem which is to pack non-overlapping spheres with the maximum volume into a convex set. The problem belongs to a class of global optimization. Convex maximization formulation of the problem is given in [1, 12]. In this paper, we formulate a new optimal control problem based on the sphere packing problem which is a nonconvex optimal control problem with phase and control constraints. A discrete version of the new optimal control problem for sphere packing problem has been<br>discussed. We examine also Malfatti’s problem [17] from a view point of optimal control theory.</p> Rentsen Enkhbat Copyright (c) 2022 Rentsen Enkhbat 2023-08-31 2023-08-31 24 17 23 10.5564/mmj.v26i24.3001 Applications of Fenchel Duality for Vector Optimization Problems <p>This paper deals with applications of Fenchel duality for vector optimization problems based on alternative definitions of the conjugate maps and the subgradient for a set-valued map having vector variables (cf. [3]). Some results investigated in Section 4 in [3] allow us to consider applications presented in this paper.</p> Lkhamsuren Altangerel Copyright (c) 2023 Lkhamsuren Altangerel 2023-08-31 2023-08-31 24 24 29 10.5564/mmj.v26i24.3002 Boundedness of Some Hilbert–Type Operators on the Weighted Morrey–Herz Spaces <p>In this paper we establish necessary and sufficient conditions for the boundedness of a general Hilbert-type operator on the weighted Morrey-Herz spaces, without imposing conditions on a homogeneous kernel. As an application, some particular cases are also considered. Our results are compared with some previously known from the literature.</p> Tserendorj Batbold Amarsaikhan Amarbayar Mario Krni´c Copyright (c) 2023 Tserendorj Batbold, Amarsaikhan Amarbayar, Mario Krni´c 2023-08-31 2023-08-31 24 30 40 10.5564/mmj.v26i24.3003