Исследование операций: учебник
This publication begins a series of works devoted to the comparison of the results of numerical methods for solving integral equations and the results of computer simulations using Poisson processes. The pros and cons of these two approaches are highlighted. The main subject of study is the model of two-species communities proposed in the works of W. Dickman and R. Lowe. The mathematical formulation of this model for an infinite domain is described. A modification of this model for work in a limited area is given. In the future, this is required for stochastic modeling. Further, the most important moments of the stochastic model are briefly described, and the features of the computer simulations built for it are noted – the algorithm used is described and the data structures used are noted. At the end of the work is a number of pictures, with the results of the above comparisons. The comparison is made within the framework of two classical scenarios of two-species models — Competition-colonization trade-off (Bay-Run scenario) and heteromyopia (People-and-Mosquitoes scenario). These drawings show very similar results, as well as some discrepancies. All this allows us to hope that the work in this direction will be very fruitful in the future.
We consider the problem of manipulability of social choice rules in the impartial anonymous and neutral culture model (IANC) and provide a new theoretical study of the IANC model, which allows us to analytically derive the difference between the Nitzan-Kelly index in the Impartial Culture (IC) and IANC models. We show in which cases this difference is almost zero, and in which the Nitzan-Kelly index for IANC is the same as for IC. However, in some cases this difference is large enough to cause changes in the relative manipulability of social choice rules. We provide an example of such cases.
В данной статье рассматриваются особенности политической системы современного Ирана и риски ее дестабилизации. В Иране существует уникальный политический режим, основанный на чрезвычайно сильной власти консервативного шиитского духовенства и подконтрольных ему силовых структур. Поэтому, по сравнению с западными государствами, множество общественно-политических свобод в стране отсутствует или серьезно ограничено. Несмотря на растущее недовольство режимом, он демонстрирует весьма высокую стабильность, что связано с его высокой религиозной легитимностью, а также выдающимися успехами в социально-демографической сфере. В стране существует соперничество между консервативными и реформаторски настроенными элитами, представители которых постоянно сменяют друг друга на президентских и парламентских выборах, что говорит о значительной политической конкуренции в стране.
The book of abstrats of 27th conference "Mathematics. Computer. Education" that was held in Dubna, Russia in January 27 - February 1, 2020. MCE conferences have a wide range of topics and goal at the consolidation of the work of scientists and education workers, saving russian scientific and educational traditions, qualifying of scientific and educational personnel in the field of mathematical modeling and information technologies, and attracting young people into science and education.
The article presents the main approaches to the study of the stochastic process of population dynamics with continuous time and space and with fixed individuals, a countable system of integro-differential equations corresponding to the dynamics of spatial moments of this process is derived, and a method for finding an approximate solution using the method of moments is described.
The article examines the problems of defining the term computer simulations of scientific experiments. The first part analyzes the original method for classifying variations of terms proposed by Duran as the most successful for demonstrating significant existing contradictions among philosophers regarding the place and role of computer simulations in the philosophy of science. In the second part of the article, the term itself is formulated by the author through the identification of the main features of computer simulations as a result of studying the nature of experimental data as transferring traces of an experiment from a graphematical space to a representative one. Following the concept of transposition, the author derives a relevant term from the essence of computer simulations revealed by him, claiming a new epistemological significance for such kind of scientific experiments for the philosophy of science.